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Sample records for chemotherapeutic drug delivery

  1. Nanocarrier-mediated co-delivery of chemotherapeutic drugs and gene agents for cancer treatment.

    PubMed

    Kang, Lin; Gao, Zhonggao; Huang, Wei; Jin, Mingji; Wang, Qiming

    2015-05-01

    The efficacy of chemotherapeutic drug in cancer treatment is often hampered by drug resistance of tumor cells, which is usually caused by abnormal gene expression. RNA interference mediated by siRNA and miRNA can selectively knock down the carcinogenic genes by targeting specific mRNAs. Therefore, combining chemotherapeutic drugs with gene agents could be a promising strategy for cancer therapy. Due to poor stability and solubility associated with gene agents and drugs, suitable protective carriers are needed and have been widely researched for the co-delivery. In this review, we summarize the most commonly used nanocarriers for co-delivery of chemotherapeutic drugs and gene agents, as well as the advances in co-delivery systems. PMID:26579443

  2. Nanocarrier-mediated co-delivery of chemotherapeutic drugs and gene agents for cancer treatment

    PubMed Central

    Kang, Lin; Gao, Zhonggao; Huang, Wei; Jin, Mingji; Wang, Qiming

    2015-01-01

    The efficacy of chemotherapeutic drug in cancer treatment is often hampered by drug resistance of tumor cells, which is usually caused by abnormal gene expression. RNA interference mediated by siRNA and miRNA can selectively knock down the carcinogenic genes by targeting specific mRNAs. Therefore, combining chemotherapeutic drugs with gene agents could be a promising strategy for cancer therapy. Due to poor stability and solubility associated with gene agents and drugs, suitable protective carriers are needed and have been widely researched for the co-delivery. In this review, we summarize the most commonly used nanocarriers for co-delivery of chemotherapeutic drugs and gene agents, as well as the advances in co-delivery systems. PMID:26579443

  3. Ultrasound-targeted microbubble destruction for chemotherapeutic drug delivery to solid tumors

    PubMed Central

    2013-01-01

    Ultrasound-targeted microbubble destruction (UTMD) is a promising technique for non-invasive, targeted drug delivery, and its applications in chemotherapeutic drug delivery to solid tumors have attracted growing interest. Ultrasound, which has been conventionally used for diagnostic imaging, has evolved as a promising tool for therapeutic applications mainly because of its ability to be focused deep inside the human body, providing a modality for targeted delivery. Although originally being introduced into clinics as ultrasound contrast agents, microbubbles (MBs) have been developed as a diagnostic and therapeutic agent that can both be tracked through non-invasive imaging and deliver therapeutic agents selectively at ultrasound-targeted locations. Whereas free drugs often possess harmful side effects, their encapsulation in MBs and subsequent local release at the targeted tissue by ultrasound triggering may help improve the margin of safety. In the past 10 years, the feasibility and safety of UTMD have been extensively tested using normal animal models. Most recently, a growing number of preclinical studies have been reported on the therapeutic benefits of UTMD in the delivery of chemotherapeutic drugs to various malignant tumors, such as brain, liver, eyelid, pancreas, and breast tumors. Increased drug concentration in tumors and reduced tumor sizes were achieved in those tumors treated with UTMD in combination with chemotherapeutic drugs, when compared to tumors treated with chemotherapy drugs alone. This review presents an overview of current preclinical applications of UTMD in chemotherapeutic drug delivery for the treatment of cancers along with a discussion of its future developments. PMID:25512858

  4. Integrin Targeted Delivery of Chemotherapeutics

    PubMed Central

    Chen, Kai; Chen, Xiaoyuan

    2011-01-01

    Targeted delivery of chemotherapeutics is defined in the sense, that is, to maximize the therapeutic index of a chemotherapeutic agent by strictly localizing its pharmacological activity to the site or tissue of action. Integrins are a family of heterodimeric transmembrane glycoproteins involved in a wide range of cell-to-extracellular matrix (ECM) and cell-to-cell interactions. As cell surface receptors, integrins readily interact with extracellular ligands and play a vital role in angiogenesis, leukocytes function and tumor development, which sets up integrins as an excellent target for chemotherapy treatment. The peptide ligands containing the arginine-glycine-aspartic acid (RGD), which displays a strong binding affinity and selectivity to integrins, particularly to integrin αvβ3, have been developed to conjugate with various conventional chemotherapeutic agents, such as small molecules, peptides and proteins, and nanoparticle-carried drugs for integtrin targeted therapeutic studies. This review highlights the recent advances in integrin targeted delivery of chemotherapeutic agents with emphasis on target of integrin αvβ3, and describes the considerations for the design of the diverse RGD peptide-chemotherapeutics conjugates and their major applications. PMID:21547159

  5. A Comprehensive Review on Cyclodextrin-Based Carriers for Delivery of Chemotherapeutic Cytotoxic Anticancer Drugs

    PubMed Central

    Gidwani, Bina; Vyas, Amber

    2015-01-01

    Most of the cytotoxic chemotherapeutic agents have poor aqueous solubility. These molecules are associated with poor physicochemical and biopharmaceutical properties, which makes the formulation difficult. An important approach in this regard is the use of combination of cyclodextrin and nanotechnology in delivery system. This paper provides an overview of limitations associated with anticancer drugs, their complexation with cyclodextrins, loading/encapsulating the complexed drugs into carriers, and various approaches used for the delivery. The present review article aims to assess the utility of cyclodextrin-based carriers like liposomes, niosomes, nanoparticles, micelles, millirods, and siRNA for delivery of antineoplastic agents. These systems based on cyclodextrin complexation and nanotechnology will camouflage the undesirable properties of drug and lead to synergistic or additive effect. Cyclodextrin-based nanotechnology seems to provide better therapeutic effect and sustain long life of healthy and recovered cells. Still, considerable study on delivery system and administration routes of cyclodextrin-based carriers is necessary with respect to their pharmacokinetics and toxicology to substantiate their safety and efficiency. In future, it would be possible to resolve the conventional and current issues associated with the development and commercialization of antineoplastic agents. PMID:26582104

  6. Tumor vascular-targeted co-delivery of anti-angiogenesis and chemotherapeutic agents by mesoporous silica nanoparticle-based drug delivery system for synergetic therapy of tumor

    PubMed Central

    Li, Xiaoyu; Wu, Meiying; Pan, Limin; Shi, Jianlin

    2016-01-01

    To overcome the drawback of drug non-selectivity in traditional chemotherapy, the construction of multifunctional targeting drug delivery systems is one of the most effective and prevailing approaches. The intratumoral anti-angiogenesis and the tumor cell-killing are two basic approaches in fighting tumors. Herein we report a novel tumor vascular-targeting multidrug delivery system using mesoporous silica nanoparticles as carrier to co-load an antiangiogenic agent (combretastatin A4) and a chemotherapeutic drug (doxorubicin) and conjugate with targeting molecules (iRGD peptide) for combined anti-angiogenesis and chemotherapy. Such a dual-loaded drug delivery system is capable of delivering the two agents at tumor vasculature and then within tumors through a differentiated drug release strategy, which consequently results in greatly improved antitumor efficacy at a very low doxorubicin dose of 1.5 mg/kg. The fast release of the antiangiogenic agent at tumor vasculatures led to the disruption of vascular structure and had a synergetic effect with the chemotherapeutic drug slowly released in the following delivery of chemotherapeutic drug into tumors. PMID:26766908

  7. Synthesis and Applications of Multimodal Hybrid Albumin Nanoparticles for Chemotherapeutic Drug Delivery and Photothermal Therapy Platforms

    NASA Astrophysics Data System (ADS)

    Peralta, Donna V.

    cellular uptake of AuNR-HSAPs via fluorescence microscopy. Finally, camptothecin (CPT) an antineoplastic agent and BACPT (7-butyl-10-aminocamptothecin) were loaded into HSAPs to combat their aqueous insolubility. BACPT-HSAPs loaded up to 5.25 micrograms BACPT/ mg of HSA. CPT encapsulation could not be determined. BACPT-HSAPs and CPT-HSAPs showed cytotoxicity to human sarcoma cells in vitro. Key words: Hybrid Nanoparticles, Photothermal Therapy, Gold Nanomaterials, Drug Delivery, Combinational Cancer Therapies, Materials, Human Serum Albumin, Colloidal Carriers.

  8. Focused ultrasound induced blood-brain barrier disruption to enhance chemotherapeutic drugs (BCNU) delivery for glioblastoma treatment

    NASA Astrophysics Data System (ADS)

    Liu, Hao-Li; Hua, Mu-Yi; Chen, Pin-Yuan; Huang, Chiung-Yin; Wang, Jiun-Jie; Wei, Kuo-Chen

    2010-03-01

    Focused ultrasound has been recently found to capable of temporally and reversibly disrupt local blood-brain barrier (BBB) and opens new frontier in delivering varies type of drugs into brain for central nerve system (CNS) disorder treatment. In this study, we aim to investigate the feasibility of delivering 1, 3-bits (2-chloroethyl) -1-nitrosourea (BCNU) to treat glioblastoma in animal models and evaluate whether this approach would gain treatment efficacy. Under the presence of microbubbles administration, a 400-kHz focused ultrasound was employed to deliver burst-tone ultrasonic energy stimulation to disrupt BBB in animal brains transcranially, and in-vivo monitored by magnetic-resonance imaging (MRI). C6-glioma cells were cultured and implanted into Sprague-Dawley rats as the brain-tumor model. BCNU deposited in brain was quantified by using high-performance liquid chromatography (HPLC), and brain tissues were examined histologically. MRI was employed to longitudinal evaluate the brain tumor treatment including the analysis of tumor progression and animal survival. We confirmed that the focused ultrasound, under the secure ultrasonic energy level, can significantly enhance the BCNU penetration through BBB over 300% than control without cause hemorrhage. Apparent improvement of treatment efficacy achieved by combining focused ultrasound with BCNU delivery, including significant suppression of tumor growth and a prolonged animal survival. This study highly support that this treatment strategy could be clinically-relevant and may help to provide another potential strategy in increasing local chemotherapeutic drugs for brain-tumor treatment.

  9. (Radiopharmaceutical and chemotherapeutic drug technology)

    SciTech Connect

    Srivastava, P.C.

    1988-01-14

    The purpose was to undertake a TOKTEN Distinguished Scientist Award assignment sponsored by the United Nations Development Programme (UNDP) in cooperation with the Council of Scientific and Industrial Research (CSIR) of India to conduct research in the areas of nucleosides and protein labeling agents at the Central Drug Research Institute (CDRI), Lucknow, and to help research scientists develop chemotherapeutic drugs in India. His work at CDRI consisted of syntheses of imidazole nucleosides, iodination reactions of nucleosides, synthesis of a bifunctional bismaleimide protein labeling agent, coordination of protein labeling studies with the Membrane Biology Group of CDRI, and initiation of several new collaborative research projects at CDRI. In addition, as a part of the CSIR-UNDP, the traveler visited several academic and industrial research institutions in India, delivered five seminars describing various aspects of radiopharmaceutical development at ORNL, and interacted extensively with scientists in India on current drug and radiopharmaceutical develop technologies in India and abroad.

  10. Lapatinib as a chemotherapeutic drug.

    PubMed

    Obajimi, Oluwakemi

    2009-11-01

    Human epidermal growth factor receptor (HER) signaling is frequently associated with the development and progression of several types of cancers. Both the MAPK and the PI3K/Akt pathways have been implicated as effectors of HER signaling by promoting anti-apoptotic and pro-proliferative effects in cancer cells. As a result, many anti-HER drugs have been developed and patented for use in cancer therapy. One such drug that was recently approved for clinical trials is lapatinib (Tykerb, GW572016). Lapatinib is a small molecule inhibitor that is active at the ATP binding site of the tyrosine kinase involved in HER signaling. Importantly, this drug has dual specificity acting at the ATP binding sites of both HER-2 and HER-1 (EGFR). This review therefore summarizes the current knowledge based on pre-clinical and clinical evidence of the therapeutic effects of lapatinib against cancer and the promising strategy of combination therapy with the possibility of circumventing the problems of drug resistance commonly faced by chemotherapeutic drugs. PMID:19522695

  11. Progress in aptamer-mediated drug delivery vehicles for cancer targeting and its implications in addressing chemotherapeutic challenges.

    PubMed

    Zhu, Jie; Huang, He; Dong, Shiwu; Ge, Liang; Zhang, Yuan

    2014-01-01

    Aptamers are novel oligonucleotides with flexible three-dimensional configurations that recognize and bind to their cognate targets, including tumor surface receptors, in a high-affinity and highly specific manner. Because of their unique intrinsic properties, a variety of aptamer-mediated nanovehicles have been developed to directionally transport anti-cancer drugs to tumor sites to minimize systemic cytotoxicity and to enhance permeation by these tumoricidal agents. Despite advances in the selection and synthesis of aptamers and in the conjugation and self-assembly of nanotechnologies, current chemotherapy and drug delivery systems face great challenges. These challenges are due to the limitations of aptamers and vehicles and because of complicated tumor mechanisms, including heterogeneity, anti-cancer drug resistance, and hypoxia-induced aberrances. In this review, we will summarize current approaches utilizing tumor surface hallmarks and aptamers and their roles and mechanisms in therapeutic nanovehicles targeting tumors. Delivery forms include nanoparticles, nanotubes, nanogels, aptamer-drug conjugates, and novel molecular trains. Moreover, the obstacles posed by the aforementioned issues will be highlighted, and possible solutions will be acknowledged. Furthermore, future perspectives will be presented, including cutting-edge integration with RNA interference nanotechnology and personalized chemotherapy, which will facilitate innovative approaches to aptamer-based therapeutics. PMID:25057317

  12. Progress in Aptamer-Mediated Drug Delivery Vehicles for Cancer Targeting and Its Implications in Addressing Chemotherapeutic Challenges

    PubMed Central

    Zhu, Jie; Huang, He; Dong, Shiwu; Ge, Liang; Zhang, Yuan

    2014-01-01

    Aptamers are novel oligonucleotides with flexible three-dimensional configurations that recognize and bind to their cognate targets, including tumor surface receptors, in a high-affinity and highly specific manner. Because of their unique intrinsic properties, a variety of aptamer-mediated nanovehicles have been developed to directionally transport anti-cancer drugs to tumor sites to minimize systemic cytotoxicity and to enhance permeation by these tumoricidal agents. Despite advances in the selection and synthesis of aptamers and in the conjugation and self-assembly of nanotechnologies, current chemotherapy and drug delivery systems face great challenges. These challenges are due to the limitations of aptamers and vehicles and because of complicated tumor mechanisms, including heterogeneity, anti-cancer drug resistance, and hypoxia-induced aberrances. In this review, we will summarize current approaches utilizing tumor surface hallmarks and aptamers and their roles and mechanisms in therapeutic nanovehicles targeting tumors. Delivery forms include nanoparticles, nanotubes, nanogels, aptamer-drug conjugates, and novel molecular trains. Moreover, the obstacles posed by the aforementioned issues will be highlighted, and possible solutions will be acknowledged. Furthermore, future perspectives will be presented, including cutting-edge integration with RNA interference nanotechnology and personalized chemotherapy, which will facilitate innovative approaches to aptamer-based therapeutics. PMID:25057317

  13. Tumour suppressor genes in chemotherapeutic drug response

    PubMed Central

    Lai, Dulcie; Visser-Grieve, Stacy; Yang, Xiaolong

    2012-01-01

    Since cancer is one of the leading causes of death worldwide, there is an urgent need to find better treatments. Currently, the use of chemotherapeutics remains the predominant option for cancer therapy. However, one of the major obstacles for successful cancer therapy using these chemotherapeutics is that patients often do not respond or eventually develop resistance after initial treatment. Therefore identification of genes involved in chemotherapeutic response is critical for predicting tumour response and treating drug-resistant cancer patients. A group of genes commonly lost or inactivated are tumour suppressor genes, which can promote the initiation and progression of cancer through regulation of various biological processes such as cell proliferation, cell death and cell migration/invasion. Recently, mounting evidence suggests that these tumour suppressor genes also play a very important role in the response of cancers to a variety of chemotherapeutic drugs. In the present review, we will provide a comprehensive overview on how major tumour suppressor genes [Rb (retinoblastoma), p53 family, cyclin-dependent kinase inhibitors, BRCA1 (breast-cancer susceptibility gene 1), PTEN (phosphatase and tensin homologue deleted on chromosome 10), Hippo pathway, etc.] are involved in chemotherapeutic drug response and discuss their applications in predicting the clinical outcome of chemotherapy for cancer patients. We also propose that tumour suppressor genes are critical chemotherapeutic targets for the successful treatment of drug-resistant cancer patients in future applications. PMID:22762204

  14. Cisplatin@US-tube Carbon Nanocapsules For Enhanced Chemotherapeutic Delivery

    PubMed Central

    Guven, Adem; Rusakova, Irene A.; Lewis, Michael T.; Wilson, Lon J.

    2012-01-01

    The use of chemotherapeutic drugs in cancer therapy is often limited by problems with administration such as insolubility, inefficient biodistribution, lack of selectivity, and inability of the drug to cross cellular barriers. To overcome these limitations, various types of drug delivery systems have been explored, and recently, carbon nanotube (CNT) materials have also garnered attention in the area of drug delivery. In this study, we describe the preparation, characterization, and in vitro testing of a new ultra-short single-walled carbon nanotube (US-tube)-based drug delivery system for the treatment of cancer. In particular, the encapsulation of cisplatin (CDDP), a widely-used anticancer drug, within US-tubes has been achieved, and the resulting CDDP@US-tube material characterized by high-resolution transmission electron microscopy (HR-TEM), energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and inductively-coupled optical emission spectrometry (ICP-OES). Dialysis studies performed in phosphate-buffered saline (PBS) at 37 °C have demonstrated that CDDP release from CDDP@US-tubes can be controlled (retarded) by wrapping the CDDP@US-tubes with Pluronic-F108 surfactant. Finally, the anticancer activity of pluronic-wrapped CDDP@US-tubes has been evaluated against two different breast cancer cell lines, MCF-7 and MDA-MB-231, and found to exhibit enhanced cytotoxicity over free CDDP after 24 hours. These studies have laid the foundation for developing US-tube-based delivery of chemotherapeutics, with drug release mainly limited to within cancer cells only. PMID:22078812

  15. Direct chemotherapeutic dual drug delivery through intra-articular injection for synergistic enhancement of rheumatoid arthritis treatment

    PubMed Central

    Reum Son, A; Kim, Da Yeon; Hun Park, Seung; Yong Jang, Ja; Kim, Kyungsook; Ju Kim, Byoung; Yun Yin, Xiang; Ho Kim, Jae; Hyun Min, Byoung; Keun Han, Dong; Suk Kim, Moon

    2015-01-01

    The effectiveness of systemic rheumatoid arthritis (RA) treatments is limited by difficulties in achieving therapeutic doses within articular joints. We evaluated the ability of intra-articular administration of injectable formulations to synergistically enhance repair of RA joints. Methotrexate-loaded hyaluronic acid (Met-HA), dexamethasone-loaded microcapsules (Dex-M), and Dex-M dispersed inside Met-HA were prepared as viscous emulsions and injected into articular joints using a needle to form a drug depot. By near-infrared (NIR) fluorescence imaging, we confirmed the local release of NIR from the depot injected into the articular joint over an extended period. In comparison with the subjects treated with Met-HA or Dex-M alone, subjects treated simultaneously with Met-HA and Dex-M exhibited faster and more significant RA repair. Collectively, these results indicated that the drug depot formed after intra-articular injection of Met-HA/Dex-M induced long-lasting drug release and allowed Met and Dex to effectively act in the articular joint, resulting in enhanced RA repair. PMID:26424611

  16. Co-delivery of chemotherapeutic drugs with vitamin E TPGS by porous PLGA nanoparticles for enhanced chemotherapy against multi-drug resistance.

    PubMed

    Zhu, Huijun; Chen, Hongbo; Zeng, Xiaowei; Wang, Zhongyuan; Zhang, Xudong; Wu, Yanping; Gao, Yongfeng; Zhang, Jinxie; Liu, Kewei; Liu, Ranyi; Cai, Lintao; Mei, Lin; Feng, Si-Shen

    2014-02-01

    We report a strategy to make use of poly(lactic-co-glycolic acid) nanoparticle (PLGA NPs) for co-delivery of docetaxel (DTX) as a model anticancer drug together with vitamin E TPGS. The latter plays a dual role as a pore-forming agent in the nanoparticles that may result in smaller particle size, higher drug encapsulation efficiency and faster drug release, and also as a bioactive agent that could inhibit P-glycoprotein to overcome multi-drug resistance of the cancer cells, The DTX-loaded PLGA NPs of 0, 10, 20 and 40% TPGS were prepared by the nanoprecipitation method and then characterized for their size and size distribution, surface morphology, physical status and encapsulation efficiency of the drug in the NPs. All four NPs were found of size ranged 100-120 nm and EE ranged 85-95% at drug loading level around 10%. The in vitro evaluation showed that the 48 h IC50 values of the free DTX and the DTX-loaded PLGA NPs of 0, 10, 20% TPGS were 2.619 and 0.474, 0.040, 0.009 μg/mL respectively, which means that the PLGA NPs formulation could be 5.57 fold effective than the free DTX and that the DTX-loaded PLGA NPs of 10 or 20% TPGS further be 11.85 and 52.7 fold effective than the DTX-loaded PLGA NPs of no TPGS (therefore, 66.0 and 284 fold effective than the free DTX). Xenograft tumor model and immunohistological staining analysis further confirmed the advantages of the strategy of co-delivery of anticancer drugs with TPGS by PLGA NPs. PMID:24360574

  17. Multiphysics and Multiscale Analysis for Chemotherapeutic Drug

    PubMed Central

    Zhang, Linan; Kim, Sung Youb; Kim, Dongchoul

    2015-01-01

    This paper presents a three-dimensional dynamic model for the chemotherapy design based on a multiphysics and multiscale approach. The model incorporates cancer cells, matrix degrading enzymes (MDEs) secreted by cancer cells, degrading extracellular matrix (ECM), and chemotherapeutic drug. Multiple mechanisms related to each component possible in chemotherapy are systematically integrated for high reliability of computational analysis of chemotherapy. Moreover, the fidelity of the estimated efficacy of chemotherapy is enhanced by atomic information associated with the diffusion characteristics of chemotherapeutic drug, which is obtained from atomic simulations. With the developed model, the invasion process of cancer cells in chemotherapy treatment is quantitatively investigated. The performed simulations suggest a substantial potential of the presented model for a reliable design technology of chemotherapy treatment. PMID:26491672

  18. Efficacy of combined photothermal therapy and chemotherapeutic drugs

    NASA Astrophysics Data System (ADS)

    Madsen, Steen J.; Shih, En-Chung; Hirschberg, Henry

    2015-03-01

    Hyperthermia has been shown to enhance the effects of chemotherapeutic agents in a wide variety of cancers. The purpose of this study was to investigate the combined effects of a number of commonly used chemotherapeutic drugs (bleomycin, doxorubicin and cisplatin) with photothermal therapy (PTT)-induced hyperthermia in an in vitro system consisting of human head and neck squamous carcinoma cells and murine lymphocytic monocytes which were used as delivery vehicles for gold-silica nanoshells (AuNS). PTT was accomplished via near infra-red (NIR) irradiation of AuNS. The results showed that PTT combined with cisplatin resulted in only a mild degree of synergism while additive effects were observed for concurrent treatments of PTT and doxorubicin and PTT and bleomycin.

  19. Smart Approach for In Situ One-Step Encapsulation and Controlled Delivery of a Chemotherapeutic Drug using Metal-Organic Framework-Drug Composites in Aqueous Media.

    PubMed

    Adhikari, Chandan; Chakraborty, Anjan

    2016-04-01

    Controlled release of an anticancer drug, doxorubicin (dox), from metal-organic framework (MOF)-drug composites is demonstrated under different external stimuli. 1,3,5-Benzenetricarboxylic acid (H3 BTC) is used as an organic ligand, and iron acetate and zinc nitrate are used as metal sources to synthesize Fe-BTC and Zn-BTC MOFs, which are known to be biocompatible. The in situ formation of MOF-drug composites demonstrates high drug loading capacity compared to conventional methods. The present methodology is devoid of any extra steps for loading the drug after synthesis. Moreover, the drug loading is also independent of pore size of the MOF as the drug molecules are embedded inside the MOF during their in situ formation. The drug release was monitored under external stimuli including change to acidic pH and the presence of biocompatible liposomes for a period of more than 72 h. Steady-state fluorescence spectroscopy is used to monitor the drug release as a function of time and confocal laser scanning microscopy is used to unravel the post-release fate of doxorubicin in the presence of liposomes. It is found that drug release rate is higher for the Zn-BTC-dox composite than for the Fe-BTC-dox composite. This is attributed to the stronger binding between dox and Fe-BTC than that between dox and Zn-BTC. This study highlights a novel approach for the preparation of MOF-drug composites in an aqueous medium for future biomedical applications. PMID:26752093

  20. Ultrasound-Guided Delivery of siRNA and a Chemotherapeutic Drug by Using Microbubble Complexes: In Vitro and In Vivo Evaluations in a Prostate Cancer Model

    PubMed Central

    Bae, Yun Jung; Yoon, Young Il; Yoon, Tae-Jong

    2016-01-01

    Objective To evaluate the effectiveness of ultrasound and microbubble-liposome complex (MLC)-mediated delivery of siRNA and doxorubicin into prostate cancer cells and its therapeutic capabilities both in vitro and in vivo. Materials and Methods Microbubble-liposome complexes conjugated with anti-human epidermal growth factor receptor type 2 (Her2) antibodies were developed to target human prostate cancer cell lines PC-3 and LNCaP. Intracellular delivery of MLC was observed by confocal microscopy. We loaded MLC with survivin-targeted small interfering RNA (siRNA) and doxorubicin, and delivered it into prostate cancer cells. The release of these agents was facilitated by ultrasound application. Cell viability was analyzed by MTT assay after the delivery of siRNA and doxorubicin. Survivin-targeted siRNA loaded MLC was delivered into the xenograft mouse tumor model. Western blotting was performed to quantify the expression of survivin in vivo. Results Confocal microscopy demonstrated substantial intracellular uptake of MLCs in LNCaP, which expresses higher levels of Her2 than PC-3. The viability of LNCaP cells was significantly reduced after the delivery of MLCs loaded with siRNA and doxorubicin (85.0 ± 2.9%), which was further potentiated by application of ultrasound (55.0 ± 3.5%, p = 0.009). Survivin expression was suppressed in vivo in LNCaP tumor xenograft model following the ultrasound and MLC-guided delivery of siRNA (77.4 ± 4.90% to 36.7 ± 1.34%, p = 0.027). Conclusion Microbubble-liposome complex can effectively target prostate cancer cells, enabling intracellular delivery of the treatment agents with the use of ultrasound. Ultrasound and MLC-mediated delivery of survivin-targeted siRNA and doxorubicin can induce prostate cell apoptosis and block survivin expression in vitro and in vivo. PMID:27390541

  1. Adsorption of doxorubicin on citrate-capped gold nanoparticles: insights into engineering potent chemotherapeutic delivery systems

    NASA Astrophysics Data System (ADS)

    Curry, Dennis; Cameron, Amanda; MacDonald, Bruce; Nganou, Collins; Scheller, Hope; Marsh, James; Beale, Stefanie; Lu, Mingsheng; Shan, Zhi; Kaliaperumal, Rajendran; Xu, Heping; Servos, Mark; Bennett, Craig; Macquarrie, Stephanie; Oakes, Ken D.; Mkandawire, Martin; Zhang, Xu

    2015-11-01

    Gold nanomaterials have received great interest for their use in cancer theranostic applications over the past two decades. Many gold nanoparticle-based drug delivery system designs rely on adsorbed ligands such as DNA or cleavable linkers to load therapeutic cargo. The heightened research interest was recently demonstrated in the simple design of nanoparticle-drug conjugates wherein drug molecules are directly adsorbed onto the as-synthesized nanoparticle surface. The potent chemotherapeutic, doxorubicin often serves as a model drug for gold nanoparticle-based delivery platforms; however, the specific interaction facilitating adsorption in this system remains understudied. Here, for the first time, we propose empirical and theoretical evidence suggestive of the main adsorption process where (1) hydrophobic forces drive doxorubicin towards the gold nanoparticle surface before (2) cation-π interactions and gold-carbonyl coordination between the drug molecule and the cations on AuNP surface facilitate DOX adsorption. In addition, biologically relevant compounds, such as serum albumin and glutathione, were shown to enhance desorption of loaded drug molecules from AuNP at physiologically relevant concentrations, providing insight into the drug release and in vivo stability of such drug conjugates.Gold nanomaterials have received great interest for their use in cancer theranostic applications over the past two decades. Many gold nanoparticle-based drug delivery system designs rely on adsorbed ligands such as DNA or cleavable linkers to load therapeutic cargo. The heightened research interest was recently demonstrated in the simple design of nanoparticle-drug conjugates wherein drug molecules are directly adsorbed onto the as-synthesized nanoparticle surface. The potent chemotherapeutic, doxorubicin often serves as a model drug for gold nanoparticle-based delivery platforms; however, the specific interaction facilitating adsorption in this system remains understudied

  2. ADVANCED MOLECULAR DESIGN OF BIOPOLYMERS FOR TRANSMUCOSAL AND INTRACELLULAR DELIVERY OF CHEMOTHERAPEUTIC AGENTS AND BIOLOGICAL THERAPEUTICS

    PubMed Central

    Liechty, William B.; Caldorera-Moore, Mary; Phillips, Margaret A.; Schoener, Cody; Peppas, Nicholas A.

    2011-01-01

    Hydrogels have been instrumental in the development of polymeric systems for controlled release of therapeutic agents. These materials are attractive for transmucosal and intracellular drug delivery because of their facile synthesis, inherent biocompatibility, tunable physicochemical properties, and capacity to respond to various physiological stimuli. In this contribution, we outline a multifaceted hydrogel-based approach for expanding the range of therapeutics in oral formulations from classical small-molecule drugs to include proteins, chemotherapeutics, and nucleic acids. Through judicious materials selection and careful design of copolymer composition and molecular architecture, we can engineer systems capable of responding to distinct physiological cues, with tunable physicochemical properties that are optimized to load, protect, and deliver valuable macromolecular payloads to their intended site of action. These hydrogel carriers, including complexation hydrogels, tethered hydrogels, interpenetrating networks, nanoscale hydrogels, and hydrogels with decorated structures are investigated for their ability respond to changes in pH, to load and release insulin and fluorescein, and remain non-toxic to Caco-2 cells. Our results suggest these novel hydrogel networks have great potential for controlled delivery of proteins, chemotherapeutics, and nucleic acids. PMID:21699934

  3. Advanced molecular design of biopolymers for transmucosal and intracellular delivery of chemotherapeutic agents and biological therapeutics.

    PubMed

    Liechty, William B; Caldorera-Moore, Mary; Phillips, Margaret A; Schoener, Cody; Peppas, Nicholas A

    2011-10-30

    Hydrogels have been instrumental in the development of polymeric systems for controlled release of therapeutic agents. These materials are attractive for transmucosal and intracellular drug delivery because of their facile synthesis, inherent biocompatibility, tunable physicochemical properties, and capacity to respond to various physiological stimuli. In this contribution, we outline a multifaceted hydrogel-based approach for expanding the range of therapeutics in oral formulations from classical small-molecule drugs to include proteins, chemotherapeutics, and nucleic acids. Through judicious material selection and careful design of copolymer composition and molecular architecture, we can engineer systems capable of responding to distinct physiological cues, with tunable physicochemical properties that are optimized to load, protect, and deliver valuable macromolecular payloads to their intended site of action. These hydrogel carriers, including complexation hydrogels, tethered hydrogels, interpenetrating networks, nanoscale hydrogels, and hydrogels with decorated structures are investigated for their ability to respond to changes in pH, to load and release insulin and fluorescein, and remain non-toxic to Caco-2 cells. Our results suggest these novel hydrogel networks have great potential for controlled delivery of proteins, chemotherapeutics, and nucleic acids. PMID:21699934

  4. Effective delivery of chemotherapeutic nanoparticles by depleting host Kupffer cells.

    PubMed

    Ohara, Yusuke; Oda, Tatsuya; Yamada, Keiichi; Hashimoto, Shinji; Akashi, Yoshimasa; Miyamoto, Ryoichi; Kobayashi, Akihiko; Fukunaga, Kiyoshi; Sasaki, Ryoko; Ohkohchi, Nobuhiro

    2012-11-15

    Although chemotherapeutic nanoparticles would confer various advantages, the majority of administrated nanoparticles are known to be spoiled by the reticuloendothelial system (RES). Intending to more effectively deliver therapeutic nanoparticles to target regions in vivo, host RES, especially Kupffer cells in the liver, have been depleted ahead of drug administration. To demonstrate this hypothesis, clodronate liposomes were preinjected into BALB/c nude mice for depletion of Kupffer cells 2 days before, and pegylated liposomal doxorubicin (Doxil) at the doses of 1.25, 2.5 and 5.0 mg/kg was administered. As a result, doxorubicin accumulation in the liver was decreased from 36 to 26% injected dose/organ by the Kupffer cells depletion, and consequently, the plasma concentration of doxorubicin was significantly enhanced threefold (from 11 to 33 μg/mL) on day 1 at 1.25 mg/kg-dose group. Doxorubicin accumulation in the tumor was increased from 0.78 to 3.0 μg/g-tissue on day 3, and tumor growth inhibition by Doxil was significantly boosted (tumor volumes from 751 to 482 mm(3) on day 24) by the Kupffer cells depletion. In conclusion, Kupffer cells depletion by clodronate liposomes enhanced the plasma concentration and antitumor effects of Doxil, and would be widely applicable for various clinical cancer chemotherapies using nanoparticles. PMID:22362271

  5. Alterations of chemotherapeutic pharmacokinetic profiles by drug–drug interactions

    PubMed Central

    Ghalib, Mohammed; Chaudhary, Imran; Goel, Sanjay

    2012-01-01

    Background Drug interactions in oncology are common place and largely ignored as we tolerate high thresholds of ‘toxic’ drug responses in these patients. However, in the era of ‘targeted’ or seemingly ‘less toxic’ therapy, these interactions are more commonly flagged and contribute significantly towards poor ‘quality of life’ and medical fatalities. Objective This review and opinion article focuses on alteration of chemotherapeutic pharmacokinetic profiles by drug interactions in the setting of polypharmacy. The assumption is that the drugs, with changes in their pharmacokinetics, will contribute towards changes in their pharmacodynamics. Methods The examples cited for such drug–drug interactions are culled from published literature with an emphasis on those interactions that have been well characterized at the molecular level. Results Although very few drug interaction studies have been performed on approved oncology based drugs, it is clear that drugs whose pharmacokinetics profiles are closely related to their pharmacodynamics will indeed result in clinically important drug interactions. Some newer mechanisms are described that involve interactions at the level of gene transcription, whereby, drug metabolism is significantly altered. However, for any given drug interaction, there does not seem to be a comprehensive model describing interactions. Conclusions Mechanisms based drug interactions are plentiful in oncology; however, there is an absolute lack of a comprehensive model that would predict drug–drug interactions. PMID:19239394

  6. Local bacteria affect the efficacy of chemotherapeutic drugs

    PubMed Central

    Lehouritis, Panos; Cummins, Joanne; Stanton, Michael; Murphy, Carola T.; McCarthy, Florence O.; Reid, Gregor; Urbaniak, Camilla; Byrne, William L.; Tangney, Mark

    2015-01-01

    In this study, the potential effects of bacteria on the efficacy of frequently used chemotherapies was examined. Bacteria and cancer cell lines were examined in vitro and in vivo for changes in the efficacy of cancer cell killing mediated by chemotherapeutic agents. Of 30 drugs examined in vitro, the efficacy of 10 was found to be significantly inhibited by certain bacteria, while the same bacteria improved the efficacy of six others. HPLC and mass spectrometry analyses of sample drugs (gemcitabine, fludarabine, cladribine, CB1954) demonstrated modification of drug chemical structure. The chemoresistance or increased cytotoxicity observed in vitro with sample drugs (gemcitabine and CB1954) was replicated in in vivo murine subcutaneous tumour models. These findings suggest that bacterial presence in the body due to systemic or local infection may influence tumour responses or off-target toxicity during chemotherapy. PMID:26416623

  7. The use of ultrasound to release chemotherapeutic drugs from micelles and liposomes.

    PubMed

    Ahmed, Salma E; Martins, Ana M; Husseini, Ghaleb A

    2015-01-01

    Several drug delivery systems have been investigated to reduce the side effects of chemotherapy by encapsulating the therapeutic agent in a nanosized carrier until it reaches the tumor site. Many of these particles are designed to be responsive to the mechanical and thermal perturbations delivered by ultrasound. Once the nanoparticle reaches the desired location, ultrasound is applied to release the chemotherapy drug only in the vicinity of the targeted (cancer) site, thus avoiding any detrimental interaction with healthy cells in the body. Studies using liposomes and micelles have shown promising results in this area, as these nanoparticles with simple, yet effective structures, showed high efficiency as drug delivery vehicles both in vitro and in vivo. This article reviews the design and application of two novel nanosized chemotherapeutic carriers (i.e. micelles and liposomes) intended to be actuated by ultrasound. PMID:25203857

  8. A novel targeted system to deliver chemotherapeutic drugs to EphA2-expressing cancer cells

    PubMed Central

    Wang, Si; Placzek, William J.; Stebbins, John L.; Mitra, Sayantan; Noberini, Roberta; Koolpe, Mitchell; Zhang, Ziming; Dahl, Russell; Pasquale, Elena B.; Pellecchia, Maurizio

    2012-01-01

    The efficacy of anti-cancer drugs is often limited by their systemic toxicities and adverse side effects. We report that the EphA2 receptor is over-expressed preferentially in several human cancer cell lines compared to normal tissues and that an EphA2 targeting peptide (YSAYPDSVPMMS) can be effective in delivering anti-cancer agents to such tumors. Hence, we report on the synthesis and characterizations of a novel EphA2-targeting agent conjugated with the chemotherapeutic drug paclitaxel. We found that the peptide-drug conjugate is dramatically more effective than paclitaxel alone at inhibiting tumor growth in a prostate cancer xenograft model, delivering significantly higher levels of drug to the tumor site. We believe these studies open the way to the development of a new class of therapeutic compounds that exploit the EphA2 receptor for drug delivery to cancer cells. PMID:22329578

  9. Strategies for improving chemotherapeutic delivery to solid tumors mediated by vascular permeability modulation

    NASA Astrophysics Data System (ADS)

    Roy Chaudhuri, Tista

    An essential mode of distribution of blood-borne chemotherapeutic agents within a solid tumor is via the micro-circulation. Poor tumor perfusion, because of a lack of functional vasculature or a lack of microvessels, as well as low tumor vascular permeability, can prevent adequate deposition of even low molecular-weight agents into the tumor. The modulation of tumor vascular function and density can provides numerous strategies for improving intratumor deposition of chemotherapeutic agents. Here we investigated strategies to improve drug delivery to two tumor types that share in common poor drug delivery, but differ in the underlying cause. First, in an angiogenesis-driven brain tumor model of Glioblastoma, the vascular permeability barrier, along with poorly-functional vasculature, hinders drug delivery. A strategy of nanoparticle-based tumor 'priming' to attack the vascular permeability barrier, employing sterically stabilized liposomal doxorubicin (SSL-DXR), was investigated. Functional and histological evaluation of tumor vasculature revealed that after an initial period of depressed vascular permeability and vascular pruning 3--4 days after SSL-DXR administration, vascular permeability and perfusion were restored and then elevated after 5--7 days. As a result of tumor priming, deposition of subsequently-administered nanoparticles was enhanced, and the efficacy of temozolomide (TMZ), if administered during the window of elevated permeability, was increased. The sequenced regimen resulted in a persistent reduction of the tumor proliferative index and a 40% suppression of tumor volume, compared to animals that received both agents simultaneously. Second, in a hypovascular, pancreatic ductal adenocarcinoma model, disruption of tumor-stromal communication via sonic hedgehog (sHH) signaling pathway inhibition mediated an indirect vascular proliferation and a more than 2-fold increase in intratumor nanoparticle deposition. Enhanced delivery of SSL-DXR in tumors pre

  10. Drug delivery systems.

    PubMed

    Robinson, D H; Mauger, J W

    1991-10-01

    New and emerging drug delivery systems for traditional drugs and the products of biotechnology are discussed, and the role of the pharmacist in ensuring the appropriate use of these systems is outlined. Advantages of advanced drug delivery systems over traditional systems are the ability to deliver a drug more selectively to a specific site; easier, more accurate, less frequent dosing; decreased variability in systemic drug concentrations; absorption that is more consistent with the site and mechanism of action; and reductions in toxic metabolites. Four basic strategies govern the mechanisms of advanced drug delivery: physical, chemical, biological, and mechanical. Oral drug delivery systems use natural and synthetic polymers to deliver the product to a specific region in the gastrointestinal tract in a timely manner that minimizes adverse effects and increases drug efficacy. Innovations in injectable and implantable delivery systems include emulsions, particulate delivery systems, micromolecular products and macromolecular drug adducts, and enzymatic-controlled delivery. Options for noninvasive drug delivery include the transdermal, respiratory, intranasal, ophthalmic, lymphatic, rectal, intravaginal, and intrauterine routes as well as topical application. Rapid growth is projected in the drug delivery systems market worldwide in the next five years. Genetic engineering has mandated the development of new strategies to deliver biotechnologically derived protein and peptide drugs and chemoimmunoconjugates. The role of the pharmacist in the era of advanced drug delivery systems will be broad based, including administering drugs, compounding, calculating dosages based on pharmacokinetic and pharmacodynamic monitoring, counseling, and research. The advent of advanced drug delivery systems offers pharmacists a new opportunity to assume an active role in patient care. PMID:1772110

  11. Nanotransporters for drug delivery.

    PubMed

    Lühmann, Tessa; Meinel, Lorenz

    2016-06-01

    Soluble nanotransporters for drugs can be profiled for targeted delivery particularly to maximize the efficacy of highly potent drugs while minimizing off target effects. This article outlines on the use of biological carrier molecules with a focus on albumin, various drug linkers for site specific release of the drug payload from the nanotransporter and strategies to combine these in various ways to meet different drug delivery demands particularly the optimization of the payload per nanotransporter. PMID:26773302

  12. Ocular drug delivery.

    PubMed

    Gaudana, Ripal; Ananthula, Hari Krishna; Parenky, Ashwin; Mitra, Ashim K

    2010-09-01

    Ocular drug delivery has been a major challenge to pharmacologists and drug delivery scientists due to its unique anatomy and physiology. Static barriers (different layers of cornea, sclera, and retina including blood aqueous and blood-retinal barriers), dynamic barriers (choroidal and conjunctival blood flow, lymphatic clearance, and tear dilution), and efflux pumps in conjunction pose a significant challenge for delivery of a drug alone or in a dosage form, especially to the posterior segment. Identification of influx transporters on various ocular tissues and designing a transporter-targeted delivery of a parent drug has gathered momentum in recent years. Parallelly, colloidal dosage forms such as nanoparticles, nanomicelles, liposomes, and microemulsions have been widely explored to overcome various static and dynamic barriers. Novel drug delivery strategies such as bioadhesive gels and fibrin sealant-based approaches were developed to sustain drug levels at the target site. Designing noninvasive sustained drug delivery systems and exploring the feasibility of topical application to deliver drugs to the posterior segment may drastically improve drug delivery in the years to come. Current developments in the field of ophthalmic drug delivery promise a significant improvement in overcoming the challenges posed by various anterior and posterior segment diseases. PMID:20437123

  13. Transdermal drug delivery

    PubMed Central

    Prausnitz, Mark R.; Langer, Robert

    2009-01-01

    Transdermal drug delivery has made an important contribution to medical practice, but has yet to fully achieve its potential as an alternative to oral delivery and hypodermic injections. First-generation transdermal delivery systems have continued their steady increase in clinical use for delivery of small, lipophilic, low-dose drugs. Second-generation delivery systems using chemical enhancers, non-cavitational ultrasound and iontophoresis have also resulted in clinical products; the ability of iontophoresis to control delivery rates in real time provides added functionality. Third-generation delivery systems target their effects to skin’s barrier layer of stratum corneum using microneedles, thermal ablation, microdermabrasion, electroporation and cavitational ultrasound. Microneedles and thermal ablation are currently progressing through clinical trials for delivery of macromolecules and vaccines, such as insulin, parathyroid hormone and influenza vaccine. Using these novel second- and third-generation enhancement strategies, transdermal delivery is poised to significantly increase impact on medicine. PMID:18997767

  14. Old drugs, novel ways out: Drug resistance toward cytotoxic chemotherapeutics.

    PubMed

    Wijdeven, Ruud H; Pang, Baoxu; Assaraf, Yehuda G; Neefjes, Jacques

    2016-09-01

    Efficacy of chemotherapy in the treatment of distinct malignancies is often hampered by drug resistance arising in the tumor. Understanding the molecular basis of drug resistance and translating this knowledge into personalized treatment decisions can enhance therapeutic efficacy and even curative outcome. Over the years, multiple drug resistance mechanisms have been identified that enable tumors to cope with the damage instigated by a specific drug or group of anti-tumor agents. Here we provide an overview of the molecular pathways leading to resistance against conventional anti-cancer drugs, with emphasis on the utility of these pathways for rational selection of treatments for individual cancer patients. We further complement the review by discussing the pitfalls and difficulties in translating these findings into novel treatment strategies for cancer patients. PMID:27620955

  15. Ultrasonic Drug Delivery – A General Review

    PubMed Central

    Pitt, William G.; Husseini, Ghaleb A.; Staples, Bryant J.

    2006-01-01

    Ultrasound (US) has an ever-increasing role in the delivery of therapeutic agents including genetic material, proteins, and chemotherapeutic agents. Cavitating gas bodies such as microbubbles are the mediators through which the energy of relatively non-interactive pressure waves is concentrated to produce forces that permeabilize cell membranes and disrupt the vesicles that carry drugs. Thus the presence of microbubbles enormously enhances delivery of genetic material, proteins and smaller chemical agents. Delivery of genetic material is greatly enhanced by ultrasound in the presence of microbubbles. Attaching the DNA directly to the microbubbles or to gas-containing liposomes enhances gene uptake even further. US-enhanced gene delivery has been studied in various tissues including cardiac, vascular, skeletal muscle, tumor and even fetal tissue. US-enhanced delivery of proteins has found most application in transdermal delivery of insulin. Cavitation events reversibly disrupt the structure of the stratus corneum to allow transport of these large molecules. Other hormones and small proteins could also be delivered transdermally. Small chemotherapeutic molecules are delivered in research settings from micelles and liposomes exposed to ultrasound. Cavitation appears to play two roles: it disrupts the structure of the carrier vesicle and releases the drug; it also makes the cell membranes and capillaries more permeable to drugs. There remains a need to better understand the physics of cavitation of microbubbles and the impact that such cavitation has upon cells and drug-carrying vesicles. PMID:16296719

  16. Intracochlear Drug Delivery Systems

    PubMed Central

    Borenstein, Jeffrey T.

    2011-01-01

    Introduction Advances in molecular biology and in the basic understanding of the mechanisms associated with sensorineural hearing loss and other diseases of the inner ear, are paving the way towards new approaches for treatments for millions of patients. However, the cochlea is a particularly challenging target for drug therapy, and new technologies will be required to provide safe and efficacious delivery of these compounds. Emerging delivery systems based on microfluidic technologies are showing promise as a means for direct intracochlear delivery. Ultimately, these systems may serve as a means for extended delivery of regenerative compounds to restore hearing in patients suffering from a host of auditory diseases. Areas covered in this review Recent progress in the development of drug delivery systems capable of direct intracochlear delivery is reviewed, including passive systems such as osmotic pumps, active microfluidic devices, and systems combined with currently available devices such as cochlear implants. The aim of this article is to provide a concise review of intracochlear drug delivery systems currently under development, and ultimately capable of being combined with emerging therapeutic compounds for the treatment of inner ear diseases. Expert Opinion Safe and efficacious treatment of auditory diseases will require the development of microscale delivery devices, capable of extended operation and direct application to the inner ear. These advances will require miniaturization and integration of multiple functions, including drug storage, delivery, power management and sensing, ultimately enabling closed-loop control and timed-sequence delivery devices for treatment of these diseases. PMID:21615213

  17. Pharmacological telomerase inhibition can sensitize drug-resistant and drug-sensitive cells to chemotherapeutic treatment.

    PubMed

    Ward, Ryan J; Autexier, Chantal

    2005-09-01

    Effective strategies to reverse or prevent chemotherapeutic resistance are required before cancer therapies can be curative. Telomerase is the ribonucleoprotein responsible for de novo synthesis and maintenance of telomeres, and its activity is predominantly observed in cancer cells. The telomerase enzyme has been successfully inhibited or inactivated to sensitize cells to cellular stresses; however, no studies have determined yet the effect of combining a pharmacological inhibitor of telomerase catalysis and traditional chemotherapeutics for the treatment of drug-sensitive or drug-resistant cancers. Here, we describe the effect of 2-[(E)-3-naphtalen-2-yl-but-2-enoylamino]-benzoic acid (BIBR1532), a small-molecule inhibitor of telomerase catalytic activity, on drug-resistant leukemia and breast cancer cells and their parental counterparts when treated in combination with chemotherapeutics. We observed that BIBR1532-treated cells show progressive telomere shortening, decreased proliferative capacity, and sensitization to chemotherapeutic treatment. These effects are telomere length-dependent, because cells insensitive to BIBR1532 or cells released from telomerase inhibition did not demonstrate changes in growth ability or drug sensitivity. Our novel observations suggest that pharmacological telomerase inhibition in combination therapy may be a valid strategy for the treatment of both drug-sensitive and drug-resistant cancers. PMID:15939802

  18. Dual-Crosslinked Methacrylated Alginate Sub-Microspheres for Intracellular Chemotherapeutic Delivery

    PubMed Central

    Scherrer, Ryan M.; Oldinski, Rachael A.

    2016-01-01

    Intracellular delivery vehicles comprised of methacrylated alginate (Alg-MA) were developed for the internalization and release of doxorubicin hydrochloride (DOX). Alg-MA was synthesized via an anhydrous reaction, and a mixture of Alg-MA and DOX was formed into sub-microspheres using a water/oil emulsion. Covalently crosslinked sub-microspheres were formed via exposure to green light, in order to investigate effects of crosslinking on drug release and cell internalization, compared to traditional techniques such as ultra violet (UV) light. Crosslinking was performed using light exposure alone, or in combination with ionic crosslinking using calcium chloride (CaCl2). Alg-MA sub-microsphere diameters were between 88 – 617 nm, and zeta-potentials were between −20 and −37 mV. Using human lung epithelial carcinoma cells (A549s) as a model, cellular internalization was confirmed using flow cytometry; different sub-microsphere formulations varied the efficiency of internalization, with UV-crosslinked sub-microspheres achieving the highest internalization percentages. While blank (non-loaded) Alg-MA sub-microspheres were non-cytotoxic to A549s, DOX-loaded sub-microspheres significantly reduced mitochondrial activity after five days of culture. Photo-crosslinked Alg-MA sub-microspheres may be a potential chemotherapeutic delivery system for cancer treatment. PMID:27378419

  19. Dual-Cross-Linked Methacrylated Alginate Sub-Microspheres for Intracellular Chemotherapeutic Delivery.

    PubMed

    Fenn, Spencer L; Miao, Tianxin; Scherrer, Ryan M; Oldinski, Rachael A

    2016-07-20

    Intracellular delivery vehicles comprised of methacrylated alginate (Alg-MA) were developed for the internalization and release of doxorubicin hydrochloride (DOX). Alg-MA was synthesized via an anhydrous reaction, and a mixture of Alg-MA and DOX was formed into sub-microspheres using a water/oil emulsion. Covalently cross-linked sub-microspheres were formed via exposure to green light, in order to investigate effects of cross-linking on drug release and cell internalization, compared to traditional techniques, such as ultraviolet (UV) light irradiation. Cross-linking was performed using light exposure alone or in combination with ionic cross-linking using calcium chloride (CaCl2). Alg-MA sub-microsphere diameters were between 88 and 617 nm, and ζ-potentials were between -20 and -37 mV. Using human lung epithelial carcinoma cells (A549) as a model, cellular internalization was confirmed using flow cytometry; different sub-microsphere formulations varied the efficiency of internalization, with UV-cross-linked sub-microspheres achieving the highest internalization percentages. While blank (nonloaded) Alg-MA submicrospheres were noncytotoxic to A549 cells, DOX-loaded sub-microspheres significantly reduced mitochondrial activity after 5 days of culture. Photo-cross-linked Alg-MA sub-microspheres may be a potential chemotherapeutic delivery system for cancer treatment. PMID:27378419

  20. Antibody–drug conjugates as novel anti-cancer chemotherapeutics

    PubMed Central

    Peters, Christina; Brown, Stuart

    2015-01-01

    Over the past couple of decades, antibody–drug conjugates (ADCs) have revolutionized the field of cancer chemotherapy. Unlike conventional treatments that damage healthy tissues upon dose escalation, ADCs utilize monoclonal antibodies (mAbs) to specifically bind tumour-associated target antigens and deliver a highly potent cytotoxic agent. The synergistic combination of mAbs conjugated to small-molecule chemotherapeutics, via a stable linker, has given rise to an extremely efficacious class of anti-cancer drugs with an already large and rapidly growing clinical pipeline. The primary objective of this paper is to review current knowledge and latest developments in the field of ADCs. Upon intravenous administration, ADCs bind to their target antigens and are internalized through receptor-mediated endocytosis. This facilitates the subsequent release of the cytotoxin, which eventually leads to apoptotic cell death of the cancer cell. The three components of ADCs (mAb, linker and cytotoxin) affect the efficacy and toxicity of the conjugate. Optimizing each one, while enhancing the functionality of the ADC as a whole, has been one of the major considerations of ADC design and development. In addition to these, the choice of clinically relevant targets and the position and number of linkages have also been the key determinants of ADC efficacy. The only marketed ADCs, brentuximab vedotin and trastuzumab emtansine (T-DM1), have demonstrated their use against both haematological and solid malignancies respectively. The success of future ADCs relies on improving target selection, increasing cytotoxin potency, developing innovative linkers and overcoming drug resistance. As more research is conducted to tackle these issues, ADCs are likely to become part of the future of targeted cancer therapeutics. PMID:26182432

  1. Ikaros expression sensitizes leukemic cells to the chemotherapeutic drug doxorubicin

    PubMed Central

    He, Licai; Gao, Shenmeng; Zhu, Zhenfeng; Chen, Shang; Gu, Haihua

    2016-01-01

    Ikaros is an important transcription factor involved in the development and differentiation of hematopoietic cells. However, its role in the treatment of hematopoietic malignancies such as leukemia is less well understood. In the present study, it was observed by data mining of the Oncomine database that high expression levels of full-length Ikaros (IK1) is correlated with increased sensitivity of cancer cells to treatments with chemotherapeutic drugs, including doxorubicin (DOX). To examine the functional significance of this observation, the expression of IK1 in a leukemia cell line was altered, and the response of leukemic cells to DOX treatment was analyzed. It was observed that overexpression of IK1 could enhance DOX-induced apoptosis, while knockdown of IK1 attenuated DOX-induced apoptosis in leukemic cells. Further experiments demonstrated that IK1 sensitized leukemic cells to DOX-induced apoptosis, probably through upregulation of caspase-9. These data suggest that high expression levels of IK1 may be a potential biomarker to predict responses of leukemia patients to treatment with chemotherapy.

  2. Metrology for drug delivery.

    PubMed

    Lucas, Peter; Klein, Stephan

    2015-08-01

    In various recently published studies, it is argued that there are underestimated risks with infusion technology, i.e., adverse incidents believed to be caused by inadequate administration of the drugs. This is particularly the case for applications involving very low-flow rates, i.e., <1 ml/h and applications involving drug delivery by means of multiple pumps. The risks in infusing are caused by a lack of awareness, incompletely understood properties of the complete drug delivery system and a lack of a proper metrological infrastructure for low-flow rates. Technical challenges such as these were the reason a European research project "Metrology for Drug Delivery" was started in 2011. In this special issue of Biomedical Engineering, the results of that project are discussed. PMID:25879307

  3. PECTIN IN CONTROLLED DRUG DELIVERY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Controlled drug delivery remains a research focus for public health to enhance patient compliance, drug efficiency and to reduce the side effects of drugs. Pectin, an edible plant polysaccharide, has shown potential for the construction of drug delivery systems for site-specific drug delivery. Sev...

  4. Single compartment drug delivery

    PubMed Central

    Cima, Michael J.; Lee, Heejin; Daniel, Karen; Tanenbaum, Laura M.; Mantzavinou, Aikaterini; Spencer, Kevin C.; Ong, Qunya; Sy, Jay C.; Santini, John; Schoellhammer, Carl M.; Blankschtein, Daniel; Langer, Robert S.

    2014-01-01

    Drug design is built on the concept that key molecular targets of disease are isolated in the diseased tissue. Systemic drug administration would be sufficient for targeting in such a case. It is, however, common for enzymes or receptors that are integral to disease to be structurally similar or identical to those that play important biological roles in normal tissues of the body. Additionally, systemic administration may not lead to local drug concentrations high enough to yield disease modification because of rapid systemic metabolism or lack of sufficient partitioning into the diseased tissue compartment. This review focuses on drug delivery methods that physically target drugs to individual compartments of the body. Compartments such as the bladder, peritoneum, brain, eye and skin are often sites of disease and can sometimes be viewed as “privileged,” since they intrinsically hinder partitioning of systemically administered agents. These compartments have become the focus of a wide array of procedures and devices for direct administration of drugs. We discuss the rationale behind single compartment drug delivery for each of these compartments, and give an overview of examples at different development stages, from the lab bench to phase III clinical trials to clinical practice. We approach single compartment drug delivery from both a translational and a technological perspective. PMID:24798478

  5. Mucoadhesive drug delivery systems

    PubMed Central

    Shaikh, Rahamatullah; Raj Singh, Thakur Raghu; Garland, Martin James; Woolfson, A David; Donnelly, Ryan F.

    2011-01-01

    Mucoadhesion is commonly defined as the adhesion between two materials, at least one of which is a mucosal surface. Over the past few decades, mucosal drug delivery has received a great deal of attention. Mucoadhesive dosage forms may be designed to enable prolonged retention at the site of application, providing a controlled rate of drug release for improved therapeutic outcome. Application of dosage forms to mucosal surfaces may be of benefit to drug molecules not amenable to the oral route, such as those that undergo acid degradation or extensive first-pass metabolism. The mucoadhesive ability of a dosage form is dependent upon a variety of factors, including the nature of the mucosal tissue and the physicochemical properties of the polymeric formulation. This review article aims to provide an overview of the various aspects of mucoadhesion, mucoadhesive materials, factors affecting mucoadhesion, evaluating methods, and finally various mucoadhesive drug delivery systems (buccal, nasal, ocular, gastro, vaginal, and rectal). PMID:21430958

  6. Optically generated ultrasound for enhanced drug delivery

    DOEpatents

    Visuri, Steven R.; Campbell, Heather L.; Da Silva, Luiz

    2002-01-01

    High frequency acoustic waves, analogous to ultrasound, can enhance the delivery of therapeutic compounds into cells. The compounds delivered may be chemotherapeutic drugs, antibiotics, photodynamic drugs or gene therapies. The therapeutic compounds are administered systemically, or preferably locally to the targeted site. Local delivery can be accomplished through a needle, cannula, or through a variety of vascular catheters, depending on the location of routes of access. To enhance the systemic or local delivery of the therapeutic compounds, high frequency acoustic waves are generated locally near the target site, and preferably near the site of compound administration. The acoustic waves are produced via laser radiation interaction with an absorbing media and can be produced via thermoelastic expansion, thermodynamic vaporization, material ablation, or plasma formation. Acoustic waves have the effect of temporarily permeabilizing the membranes of local cells, increasing the diffusion of the therapeutic compound into the cells, allowing for decreased total body dosages, decreased side effects, and enabling new therapies.

  7. Nanotopography applications in drug delivery.

    PubMed

    Walsh, Laura A; Allen, Jessica L; Desai, Tejal A

    2015-01-01

    Refinement of micro- and nanofabrication in the semiconductor field has led to innovations in biomedical technologies. Nanotopography, in particular, shows great potential in facilitating drug delivery. The flexibility of fabrication techniques has created a diverse array of topographies that have been developed for drug delivery applications. Nanowires and nanostraws deliver drug cytosolically for in vitro and ex vivo applications. In vivo drug delivery is limited by the barrier function of the epithelium. Nanowires on microspheres increase adhesion and residence time for oral drug delivery, while also increasing permeability of the epithelium. Low aspect ratio nanocolumns increase paracellular permeability, and in conjunction with microneedles increase transdermal drug delivery of biologics in vivo. In summary, nanotopography is a versatile tool for drug delivery. It can deliver directly to cells or be used for in vivo delivery across epithelial barriers. This editorial highlights the application of nanotopography in the field of drug delivery. PMID:26512871

  8. Photomechanical drug delivery

    NASA Astrophysics Data System (ADS)

    Doukas, Apostolos G.; Lee, Shun

    2000-05-01

    Photomechanical waves (PW) are generated by Q-switched or mode-locked lasers. Ablation is a reliable method for generating PWs with consistent characteristics. Depending on the laser wavelength and target material, PWs with different parameters can be generated which allows the investigation of PWs with cells and tissue. PWs have been shown to permeabilize the stratum corneum (SC) in vivo and facilitate the transport of drugs into the skin. Once a drug has diffused into the dermis it can enter the vasculature, thus producing a systemic effect. Fluorescence microscopy of biopsies show that 40-kDa molecules can be delivered to a depth of > 300 micrometers into the viable skin of rats. Many important drugs such as insulin, and erythropoietin are smaller or comparable in size, making the PWs attractive for transdermal drug delivery. There are three possible pathways through the SC: Transappendageal via hair follicles or other appendages, transcellular through the corneocytes, and intercellular via the extracellular matrix. The intracellular route appears to be the most likely pathway of drug delivery through the SC.

  9. MEMS: Enabled Drug Delivery Systems.

    PubMed

    Cobo, Angelica; Sheybani, Roya; Meng, Ellis

    2015-05-01

    Drug delivery systems play a crucial role in the treatment and management of medical conditions. Microelectromechanical systems (MEMS) technologies have allowed the development of advanced miniaturized devices for medical and biological applications. This Review presents the use of MEMS technologies to produce drug delivery devices detailing the delivery mechanisms, device formats employed, and various biomedical applications. The integration of dosing control systems, examples of commercially available microtechnology-enabled drug delivery devices, remaining challenges, and future outlook are also discussed. PMID:25703045

  10. Hypoxia Responsive Drug Delivery Systems in Tumor Therapy.

    PubMed

    Alimoradi, Houman; Matikonda, Siddharth S; Gamble, Allan B; Giles, Gregory I; Greish, Khaled

    2016-01-01

    Hypoxia is a common characteristic of solid tumors. It is mainly determined by low levels of oxygen resulting from imperfect vascular networks supplying most tumors. In an attempt to improve the present chemotherapeutic treatment and reduce associated side effects, several prodrug strategies have been introduced to achieve hypoxia-specific delivery of cytotoxic anticancer agents. With the advances in nanotechnology, novel delivery systems activated by the consequent outcomes of hypoxia have been developed. However, developing hypoxia responsive drug delivery systems (which only depend on low oxygen levels) is currently naïve. This review discusses four main hypoxia responsive delivery systems: polymeric based drug delivery systems, oxygen delivery systems combined with radiotherapy and chemotherapy, anaerobic bacteria which are used for delivery of genes to express anticancer proteins such as tumor necrosis alpha (TNF-α) and hypoxia-inducible transcription factors 1 alpha (HIF1α) responsive gene delivery systems. PMID:26898739

  11. Polymers for Drug Delivery Systems

    PubMed Central

    Liechty, William B.; Kryscio, David R.; Slaughter, Brandon V.; Peppas, Nicholas A.

    2012-01-01

    Polymers have played an integral role in the advancement of drug delivery technology by providing controlled release of therapeutic agents in constant doses over long periods, cyclic dosage, and tunable release of both hydrophilic and hydrophobic drugs. From early beginnings using off-the-shelf materials, the field has grown tremendously, driven in part by the innovations of chemical engineers. Modern advances in drug delivery are now predicated upon the rational design of polymers tailored for specific cargo and engineered to exert distinct biological functions. In this review, we highlight the fundamental drug delivery systems and their mathematical foundations and discuss the physiological barriers to drug delivery. We review the origins and applications of stimuli-responsive polymer systems and polymer therapeutics such as polymer-protein and polymer-drug conjugates. The latest developments in polymers capable of molecular recognition or directing intracellular delivery are surveyed to illustrate areas of research advancing the frontiers of drug delivery. PMID:22432577

  12. Effect of Paullinia cupana on MCF-7 breast cancer cell response to chemotherapeutic drugs.

    PubMed

    Hertz, Everaldo; Cadoná, Francine Carla; Machado, Alencar Kolinski; Azzolin, Verônica; Holmrich, Sabrina; Assmann, Charles; Ledur, Pauline; Ribeiro, Euler Esteves; DE Souza Filho, Olmiro Cezimbra; Mânica-Cattani, Maria Fernanda; DA Cruz, Ivana Beatrice Mânica

    2015-01-01

    Previous studies suggested that certain plants, such as guarana (Paullinia cupana), exert a protective effect against cancer-related fatigue in breast cancer patients undergoing chemotherapy. However, guarana possesses bioactive molecules, such as caffeine and catechin, which may affect the pharmacological properties of antitumor drugs. Therefore, the aim of this study was to evaluate the effects of guarana on breast cancer cell response to 7 chemotherapeutic agents currently used in the treatment of breast cancer. To perform this study, MCF-7 breast cancer cells were cultured under controlled conditions and exposed to 1, 5 and 10 µg/ml guarana concentrations, with and without chemotherapeutics (gemcitabine, vinorelbine, methotrexate, 5-fluorouracil, paclitaxel, doxorubicin and cyclophosphamide). The effect of these treatments on MCF-7 cell viability and proliferation was spectrophotometrically analyzed with the MTT assay. The main results demonstrated an antiproliferative effect of guarana at concentrations of 5 and 10 µg/ml and a significant effect on chemotherapeutic drug action. In general, guarana improved the antiproliferative effect of chemotherapeutic agents, causing a decrease of >40% in cell growth after 72 h of exposure. The results suggested an interaction of guarana with the chemotherapeutic drugs, which requires confirmation by in vivo complementary studies. PMID:25469267

  13. Effect of Paullinia cupana on MCF-7 breast cancer cell response to chemotherapeutic drugs

    PubMed Central

    HERTZ, EVERALDO; CADONÁ, FRANCINE CARLA; MACHADO, ALENCAR KOLINSKI; AZZOLIN, VERÔNICA; HOLMRICH, SABRINA; ASSMANN, CHARLES; LEDUR, PAULINE; RIBEIRO, EULER ESTEVES; DE SOUZA FILHO, OLMIRO CEZIMBRA; MÂNICA-CATTANI, MARIA FERNANDA; DA CRUZ, IVANA BEATRICE MÂNICA

    2015-01-01

    Previous studies suggested that certain plants, such as guarana (Paullinia cupana), exert a protective effect against cancer-related fatigue in breast cancer patients undergoing chemotherapy. However, guarana possesses bioactive molecules, such as caffeine and catechin, which may affect the pharmacological properties of antitumor drugs. Therefore, the aim of this study was to evaluate the effects of guarana on breast cancer cell response to 7 chemotherapeutic agents currently used in the treatment of breast cancer. To perform this study, MCF-7 breast cancer cells were cultured under controlled conditions and exposed to 1, 5 and 10 µg/ml guarana concentrations, with and without chemotherapeutics (gemcitabine, vinorelbine, methotrexate, 5-fluorouracil, paclitaxel, doxorubicin and cyclophosphamide). The effect of these treatments on MCF-7 cell viability and proliferation was spectrophotometrically analyzed with the MTT assay. The main results demonstrated an antiproliferative effect of guarana at concentrations of 5 and 10 µg/ml and a significant effect on chemotherapeutic drug action. In general, guarana improved the antiproliferative effect of chemotherapeutic agents, causing a decrease of >40% in cell growth after 72 h of exposure. The results suggested an interaction of guarana with the chemotherapeutic drugs, which requires confirmation by in vivo complementary studies. PMID:25469267

  14. Synthetic lethal approaches for assessing combinatorial efficacy of chemotherapeutic drugs.

    PubMed

    Jackson, Rebecca A; Chen, Ee Sin

    2016-06-01

    The recent advances in pharmacogenomics have made personalized medicine no longer a pipedream but a precise and powerful way to tailor individualized cancer treatment strategies. Cancer is a devastating disease, and contemporary chemotherapeutic strategies now integrate several agents in the treatment of some types of cancer, with the intent to block more than one target simultaneously. This constitutes the premise of synthetic lethality, an attractive therapeutic strategy already demonstrating clinical success in patients with breast and ovarian cancers. Synthetic lethal combinations offer the potential to also target the hitherto "undruggable" mutations that have challenged the cancer field for decades. However, synthetic lethality in clinical cancer therapy is very much still in its infancy, and selecting the most appropriate combinations-or synthetic lethal pairs-is not always an intuitive process. Here, we review some of the recent progress in identifying synthetic lethal combinations and their potential for therapy and highlight some of the tools through which synthetic lethal pairs are identified. PMID:26803999

  15. Improving drug delivery to solid tumors: priming the tumor microenvironment.

    PubMed

    Khawar, Iftikhar Ali; Kim, Jung Ho; Kuh, Hyo-Jeong

    2015-03-10

    Malignant transformation and growth of the tumor mass tend to induce changes in the surrounding microenvironment. Abnormality of the tumor microenvironment provides a driving force leading not only to tumor progression, including invasion and metastasis, but also to acquisition of drug resistance, including pharmacokinetic (drug delivery-related) and pharmacodynamic (sensitivity-related) resistance. Drug delivery systems exploiting the enhanced permeability and retention (EPR) effect and active targeting moieties were expected to be able to cope with delivery-related drug resistance. However, recent evidence supports a considerable barrier role of tumors via various mechanisms, which results in imperfect or inefficient EPR and/or targeting effect. The components of the tumor microenvironment such as abnormal tumor vascular system, deregulated composition of the extracellular matrix, and interstitial hypertension (elevated interstitial fluid pressure) collectively or cooperatively hinder the drug distribution, which is prerequisite to the efficacy of nanoparticles and small-molecule drugs used in cancer medicine. Hence, the abnormal tumor microenvironment has recently been suggested to be a promising target for the improvement of drug delivery to improve therapeutic efficacy. Strategies to modulate the abnormal tumor microenvironment, referred to here as "solid tumor priming" (vascular normalization and/or solid stress alleviation leading to improvement in blood perfusion and convective molecular movement), have shown promising results in the enhancement of drug delivery and anticancer efficacy. These strategies may provide a novel avenue for the development of new chemotherapeutics and combination chemotherapeutic regimens as well as reassessment of previously ineffective agents. PMID:25526702

  16. Exploiting the Tumor Phenotype Using Biodegradable Submicron Carriers of Chemotherapeutic Drugs

    PubMed Central

    Geary, Sean M.; Salem, Aliasger K.

    2014-01-01

    Tumor tissues possess characteristics that distinguish them from healthy tissues and make them attractive targets for submicron carriers of chemotherapeutic drugs (CTX). CTX are generally administered systemically in free form to cancer patients resulting in unwanted cytotoxic effects and placing limitations on the deliverable CTX dose. In an effort to raise the therapeutic index of CTX there are now liposome-based CTX formulations in clinical use that are more tumor specific than the free form of CTX. However, progression to liposome-based chemotherapy in the clinic has been slow and there have been no approved formulations introduced in the last decade. Alternative carrier systems such as those made from the biodegradable polymer poly(lactic-co-glycolic) acid (PLGA) have been investigated in preclinical settings with promising outcomes. Here we review the principle behind biodegradable submicron carriers as CTX delivery vehicles for solid tumors with a specific focUS on liposomes and PLGA-based carriers, highlighting the strengths and weaknesses of each system. PMID:25271435

  17. Apical ABC transporters and cancer chemotherapeutic drug disposition.

    PubMed

    Durmus, Selvi; Hendrikx, Jeroen J M A; Schinkel, Alfred H

    2015-01-01

    ATP-binding cassette (ABC) transporters are transmembrane efflux transporters that mediate cellular extrusion of a broad range of substrates ranging from amino acids, lipids, and ions to xenobiotics including many anticancer drugs. ABCB1 (P-GP) and ABCG2 (BCRP) are the most extensively studied apical ABC drug efflux transporters. They are highly expressed in apical membranes of many pharmacokinetically relevant tissues such as epithelial cells of the small intestine and endothelial cells of the blood capillaries in brain and testis, and in the placental maternal-fetal barrier. In these tissues, they have a protective function as they efflux their substrates back to the intestinal lumen or blood and thus restrict the intestinal uptake and tissue disposition of many compounds. This presents a major challenge for the use of many (anticancer) drugs, as most currently used anticancer drugs are substrates of these transporters. Herein, we review the latest findings on the role of apical ABC transporters in the disposition of anticancer drugs. We discuss that many new, rationally designed anticancer drugs are substrates of these transporters and that their oral availability and/or brain disposition are affected by this interaction. We also summarize studies that investigate the improvement of oral availability and brain disposition of many cytotoxic (e.g., taxanes) and rationally designed (e.g., tyrosine kinase inhibitor) anticancer drugs, using chemical inhibitors of these transporters. These findings provide a better understanding of the importance of apical ABC transporters in chemotherapy and may therefore advance translation of promising preclinical insights and approaches to clinical studies. PMID:25640265

  18. ATP-triggered anticancer drug delivery

    NASA Astrophysics Data System (ADS)

    Mo, Ran; Jiang, Tianyue; Disanto, Rocco; Tai, Wanyi; Gu, Zhen

    2014-03-01

    Stimuli-triggered drug delivery systems have been increasingly used to promote physiological specificity and on-demand therapeutic efficacy of anticancer drugs. Here we utilize adenosine-5'-triphosphate (ATP) as a trigger for the controlled release of anticancer drugs. We demonstrate that polymeric nanocarriers functionalized with an ATP-binding aptamer-incorporated DNA motif can selectively release the intercalating doxorubicin via a conformational switch when in an ATP-rich environment. The half-maximal inhibitory concentration of ATP-responsive nanovehicles is 0.24 μM in MDA-MB-231 cells, a 3.6-fold increase in the cytotoxicity compared with that of non-ATP-responsive nanovehicles. Equipped with an outer shell crosslinked by hyaluronic acid, a specific tumour-targeting ligand, the ATP-responsive nanocarriers present an improvement in the chemotherapeutic inhibition of tumour growth using xenograft MDA-MB-231 tumour-bearing mice. This ATP-triggered drug release system provides a more sophisticated drug delivery system, which can differentiate ATP levels to facilitate the selective release of drugs.

  19. In vivo enhancement of anticancer therapy using bare or chemotherapeutic drug-bearing nanodiamond particles

    PubMed Central

    Li, Yingqi; Tong, Yaoli; Cao, Ruixia; Tian, Zhimei; Yang, Binsheng; Yang, Pin

    2014-01-01

    Background This study investigated the use of nanodiamond particles (NDs) as a promising material for drug delivery in vivo and in vitro. Methods HepG2 cells (a human hepatic carcinoma cell line) were used to determine the characteristics of a nanodiamond-doxorubicin complex (ND-DOX) when taken up by cells in vitro using laser scanning confocal microscopy and dialysis experiments. We also compared the survival rate and histopathology of tumor-bearing mice after treatment with NDs or ND-DOX in vivo. Results In vitro investigation showed that ND-DOX has slow and sustained drug release characteristics compared with free doxorubicin. In vivo, the survival rate of tumor-bearing mice treated with ND-DOX was four times greater than that of mice treated with free doxorubicin. Interestingly, the survival rate in mice treated with NDs alone was close to that of mice treated with free doxorubicin. This indicates that treatment with ND-DOX can prolong the lifespan of tumor-bearing mice significantly compared with conventional doxorubicin and that NDs can have this effect as well. Histopathological analysis showed that neither the NDs nor ND-DOX were toxic to the kidney, liver, or spleen in contrast with the well-known toxic effects of free doxorubicin on the kidney and liver. Further, both the bare NDs and ND-DOX could suppress tumor growth effectively. Conclusion NDs can potentially prolong survival, and ND-DOX may act as a nanodrug with promising chemotherapeutic efficacy and safety. PMID:24591828

  20. Nanocarrier mediated Delivery of siRNA/miRNA in Combination with Chemotherapeutic Agents for Cancer Therapy: Current Progress and Advances

    PubMed Central

    Gandhi, Nishant S.; Tekade, Rakesh K.; Chougule, Mahavir B.

    2014-01-01

    Chemotherapeutic agents have certain limitations when it comes to treating cancer, the most important being severe side effects along with multidrug resistance developed against them. Tumor cells exhibits drug resistance due to activation of various cellular level processes viz. activation of drug efflux pumps, anti-apoptotic defense mechanisms etc. Currently, RNA interference (RNAi) based therapeutic approaches are under vibrant scrutinization to seek cancer cure. Especially small interfering RNA (siRNA) and micro RNA (miRNA), are able to knock down the carcinogenic genes by targeting the mRNA expression, which underlies the uniqueness of this therapeutic approach. Recent research focus in the regime of cancer therapy involves the engagement of targeted delivery of siRNA/miRNA in combinations with other therapeutic agents (such as gene, DNA or chemotherapeutic drug) for targeting permeability glycoprotein (P-gp), Multidrug resistant protein 1(MRP-1), B-cell lymphoma (BCL-2) and other targets that are mainly responsible for resistance in cancer therapy. RNAi-chemotherapeutic drug combinations have also been found to be effective against different molecular targets as well and can increase the sensitization of cancer cells to therapy several folds. However, due to stability issues associated with siRNA/miRNA suitable protective carrier is needed and nanotechnology based approaches have been widely explored to overcome these drawbacks. Furthermore, it has been univocally advocated that the co-delivery of siRNA/miRNA with other chemodrugs significantly enhances their capability to overcome cancer resistance compared to naked counterparts. The objective of this article is to review recent nanocarrier based approaches adopted for the delivery of siRNA/miRNA combinations with other anticancer agents (siRNA/miRNA/pDNA/chemodrugs) to treat cancer. PMID:25204288

  1. Irinotecan, a key chemotherapeutic drug for metastatic colorectal cancer

    PubMed Central

    Fujita, Ken-ichi; Kubota, Yutaro; Ishida, Hiroo; Sasaki, Yasutsuna

    2015-01-01

    Irinotecan hydrochloride is a camptothecin derivative that exerts antitumor activity against a variety of tumors. SN-38 produced in the body by carboxylesterase is the active metabolite of irinotecan. After irinotecan was introduced for the treatment of metastatic colorectal cancer (CRC) at the end of the last century, survival has improved dramatically. Irinotecan is now combined with 5-fluorouracil, oxaliplatin and several molecularly-targeted anticancer drugs, resulting in the extension of overall survival to longer than 30 mo. Severe, occasionally life-threatening toxicity occurs sporadically, even in patients in relatively good condition who have a low risk of chemotherapy-induced toxicity, often causing the failure of irinotecan-based chemotherapy. Clinical pharmacological studies have revealed that such severe toxicity is related to exposure to SN-38 and genetic polymorphisms in UDP-glucuronosyltransferase 1A1 gene. The large inter- and intra-patient variability in systemic exposure to SN-38 is determined not only by genetic factors but also by physiological and environmental factors. This review first summarizes the roles of irinotecan in chemotherapy for metastatic CRC and then discusses the optimal dosing of irinotecan based on the aforementioned factors affecting systemic exposure to SN-38, with the ultimate goal of achieving personalized irinotecan-based chemotherapy. PMID:26604633

  2. Irinotecan, a key chemotherapeutic drug for metastatic colorectal cancer.

    PubMed

    Fujita, Ken-ichi; Kubota, Yutaro; Ishida, Hiroo; Sasaki, Yasutsuna

    2015-11-21

    Irinotecan hydrochloride is a camptothecin derivative that exerts antitumor activity against a variety of tumors. SN-38 produced in the body by carboxylesterase is the active metabolite of irinotecan. After irinotecan was introduced for the treatment of metastatic colorectal cancer (CRC) at the end of the last century, survival has improved dramatically. Irinotecan is now combined with 5-fluorouracil, oxaliplatin and several molecularly-targeted anticancer drugs, resulting in the extension of overall survival to longer than 30 mo. Severe, occasionally life-threatening toxicity occurs sporadically, even in patients in relatively good condition who have a low risk of chemotherapy-induced toxicity, often causing the failure of irinotecan-based chemotherapy. Clinical pharmacological studies have revealed that such severe toxicity is related to exposure to SN-38 and genetic polymorphisms in UDP-glucuronosyltransferase 1A1 gene. The large inter- and intra-patient variability in systemic exposure to SN-38 is determined not only by genetic factors but also by physiological and environmental factors. This review first summarizes the roles of irinotecan in chemotherapy for metastatic CRC and then discusses the optimal dosing of irinotecan based on the aforementioned factors affecting systemic exposure to SN-38, with the ultimate goal of achieving personalized irinotecan-based chemotherapy. PMID:26604633

  3. Polymer Particulates in Drug Delivery.

    PubMed

    Kaur, Harmeet; Kumar, Virender; Kumar, Krishan; Rathor, Sandeep; Kumari, Parveen; Singh, Jasbir

    2016-01-01

    Development of effective drug delivery systems is important for medicine and healthcare. Polymer particulates (micro- and nanoparticles) have opened new opportunities in the field of drug delivery by overcoming various limitations of conventional delivery methods. The properties of polymeric particles can be readily tuned by precisely engineering the constituent blocks of polymers for improving drug loading, release rate, pharmacokinetics, targeting, etc. The end-groups of various polymers can be readily modified with ligands making them suitable for recognizing by cell-specific receptors, providing cellular specificity, and superior intracellular delivery. This review will mainly cover delivery of many potential drugs and biomolecules by means of polymeric microparticles, nanoparticles and copolymer micelles or assemblies. An overview about formulation methods of polymer particulates has also been addressed. Attempt has been made to cover all the potential polymers that are well known in pharmaceutical history. PMID:26898740

  4. Osmotic micropumps for drug delivery.

    PubMed

    Herrlich, Simon; Spieth, Sven; Messner, Stephan; Zengerle, Roland

    2012-11-01

    This paper reviews miniaturized drug delivery systems applying osmotic principles for pumping. Osmotic micropumps require no electrical energy and consequently enable drug delivery systems of smallest size for a broad field of new applications. In contrast to common tablets, these pumps provide constant (zero-order) drug release rates. This facilitates systems for long term use not limited by gastrointestinal transit time and first-pass metabolism. The review focuses on parenteral routes of administration targeting drug delivery either in a site-specific or systemic way. Osmotic pumps consist of three building blocks: osmotic agent, solvent, and drug. This is used to categorize pumps into (i) single compartment systems using water from body fluids as solvent and the drug itself as the osmotic agent, (ii) two compartment systems employing a separate osmotic agent, and (iii) multi-compartment architectures employing solvent, drug and osmotic agent separately. In parallel to the micropumps, relevant applications and therapies are discussed. PMID:22370615

  5. Bioresponsive matrices in drug delivery

    PubMed Central

    2010-01-01

    For years, the field of drug delivery has focused on (1) controlling the release of a therapeutic and (2) targeting the therapeutic to a specific cell type. These research endeavors have concentrated mainly on the development of new degradable polymers and molecule-labeled drug delivery vehicles. Recent interest in biomaterials that respond to their environment have opened new methods to trigger the release of drugs and localize the therapeutic within a particular site. These novel biomaterials, usually termed "smart" or "intelligent", are able to deliver a therapeutic agent based on either environmental cues or a remote stimulus. Stimuli-responsive materials could potentially elicit a therapeutically effective dose without adverse side effects. Polymers responding to different stimuli, such as pH, light, temperature, ultrasound, magnetism, or biomolecules have been investigated as potential drug delivery vehicles. This review describes the most recent advances in "smart" drug delivery systems that respond to one or multiple stimuli. PMID:21114841

  6. Beta-lactams and their potential use as novel anticancer chemotherapeutics drugs.

    PubMed

    Kuhn, Deborah; Coates, Cristina; Daniel, Kenyon; Chen, Di; Bhuiyan, Mohammad; Kazi, Aslamuzzaman; Turos, Edward; Dou, Q Ping

    2004-09-01

    The discovery of natural and synthetic antibiotics is one of the most important medical breakthroughs in human history. Many diseases, such as bacterial meningitis, pneumonia, and septicemia, are now curable with the use of antibiotics. Antibiotics are efficacious, generally well tolerated in patients, and have a low toxicity level. It is for these reasons antibiotics remain an attractive target for drug discovery. Traditional beta-lactam antibiotics (e.g. penicillins, penems, cephalosporins) have a bicyclic ring structure that is conformationally rigid and functions to inhibit bacterial cell wall synthesis. In addition to the bactericidal action of antibiotics, it has been discovered that many antibiotics are capable of inhibiting tumor cell growth. There are currently many antitumor antibiotics approved for cancer therapy, which work to inhibit tumor cell growth by DNA intercalation. The use of beta-lactams as prodrugs has also met with success by aiding delivery of the chemotherapeutic directly to tumor sites. Recently, a novel class of N-thiolated monobactams, so termed because they possess a monocyclic ring instead of the bicyclic ring, has been found to induce apoptosis potently and specifically in many tumor cell lines but not in normal, non-transformed cell lines. Other beta-lactams, such as the polyaromatics, have been found to slow or inhibit tumor cell growth, and the 4-alkylidene beta-lactams are capable of inhibiting matrix metalloproteinases and leukocyte elactase activity. These data indicate that synthesis and evaluation of beta-lactams are a promising area for further development in anticancer research. PMID:15358584

  7. Assessment of urinary excretion of antimalarial drugs in large-scale chemotherapeutic eradication projects.

    PubMed

    BRUCE-CHWATT, L J

    1959-01-01

    Assessment of the urinary excretion of an antimalarial drug is a useful means of checking the amount of drug administered and the regularity of intake. The author describes the various methods available for the qualitative and quantitative estimation of antimalarial drugs in urine and discusses their relative merits, with special reference to their suitability for use in the field. He points out the difficulties involved in estimating the urinary excretion of antimalarials in large-scale chemotherapeutic eradication projects and stress the importance of simplifying testing techniques as far as possible. PMID:13805135

  8. Nanoencapsulation for drug delivery

    PubMed Central

    Kumari, Avnesh; Singla, Rubbel; Guliani, Anika; Yadav, Sudesh Kumar

    2014-01-01

    Nanoencapsulation of drug/small molecules in nanocarriers (NCs) is a very promising approach for development of nanomedicine. Modern drug encapsulation methods allow efficient loading of drug molecules inside the NCs thereby reducing systemic toxicity associated with drugs. Targeting of NCs can enhance the accumulation of nanonencapsulated drug at the diseased site. This article focussed on the synthesis methods, drug loading, drug release mechanism and cellular response of nanoencapsulated drugs on liposomes, micelles, carbon nanotubes, dendrimers, and magnetic NCs. Also the uses of these various NCs have been highlighted in the field of nanotechnology. PMID:26417260

  9. Photoresponsive nanoparticles for drug delivery

    PubMed Central

    Rwei, Alina Y.; Wang, Weiping; Kohane, Daniel S.

    2015-01-01

    Summary Externally triggerable drug delivery systems provide a strategy for the delivery of therapeutic agents preferentially to a target site, presenting the ability to enhance therapeutic efficacy while reducing side effects. Light is a versatile and easily tuned external stimulus that can provide spatiotemporal control. Here we will review the use of nanoparticles in which light triggers drug release or induces particle binding to tissues (phototargeting). PMID:26644797

  10. Nanoscale coordination polymers for anticancer drug delivery

    NASA Astrophysics Data System (ADS)

    Phillips, Rachel Huxford

    This dissertation reports the synthesis and characterization of nanoscale coordination polymers (NCPs) for anticancer drug delivery. Nanoparticles have been explored in order to address the limitations of small molecule chemotherapeutics. NCPs have been investigated as drug delivery vehicles as they can exhibit the same beneficial properties as the bulk metal-organic frameworks as well as interesting characteristics that are unique to nanomaterials. Gd-MTX (MTX = methotrexate) NCPs with a MTX loading of 71.6 wt% were synthesized and stabilized by encapsulation within a lipid bilayer containing anisamide (AA), a small molecule that targets sigma receptors which are overexpressed in many cancer tissues. Functionalization with AA allows for targeted delivery and controlled release to cancer cells, as shown by enhanced efficacy against leukemia cells. The NCPs were doped with Ru(bpy)32+ (bpy = 2,2'-bipyridine), and this formulation was utilized as an optical imaging agent by confocal microscopy. NCPs containing the chemotherapeutic pemetrexed (PMX) were synthesized using different binding metals. Zr-based materials could not be stabilized by encapsulation with a lipid bilayer, and Gd-based materials showed that PMX had degraded during synthesis. However, Hf-based NCPs containing 19.7 wt% PMX were stabilized by a lipid coating and showed in vitro efficacy against non-small cell lung cancer (NSCLC) cell lines. Enhanced efficacy was observed for formulations containing AA. Additionally, NCP formulations containing the cisplatin prodrug disuccinatocisplatin were prepared; one of these formulations could be stabilized by encapsulation within a lipid layer. Coating with a lipid layer doped with AA rendered this formulation an active targeting agent. The resulting formulation proved more potent than free cisplatin in NSCLC cell lines. Improved NCP uptake was demonstrated by confocal microscopy and competitive binding assays. Finally, a Pt(IV) oxaliplatin prodrug was

  11. Hypoxia suppresses chemotherapeutic drug-induced p53 Serine 46 phosphorylation by triggering HIPK2 degradation.

    PubMed

    Moehlenbrink, Jutta; Bitomsky, Nadja; Hofmann, Thomas G

    2010-06-01

    The molecular mechanisms by which hypoxic tumor cells escape radio- and chemotherapy are largely unclear. Homeodomain-interacting protein kinase 2 (HIPK2) drives the apoptotic program in response to DNA-damaging chemotherapeutic drug treatment by phosphorylating the tumor suppressor protein p53 at Ser46. HIPK2 is kept inactive in unstressed cells through ubiquitination and degradation facilitated by the ubiquitin ligases WSB1 and Siah1. Here, we demonstrate that HIPK2 is degraded during hypoxia in a proteasome-dependent and partially Siah1-dependent fashion. Concordantly, hypoxic tumor cells show an impaired p53 Ser46 phosphorylation in response to treatment with the chemotherapeutic Adriamycin. Remarkably, proteasome-inhibition rescues HIPK2 expression in hypoxic hepatoma cells and restores p53 Ser46 phosphorylation and caspase activity after Adriamycin treatment. Our findings suggest a molecular mechanism by which hypoxic cancer cells can escape chemotherapeutic drug treatment and suggest proteasome-inhibition as a promising approach to sensitise hypoxic cancer cells to therapy. PMID:20018442

  12. The Role of Transporters in the Toxicity of Chemotherapeutic Drugs: Focus on Transporters for Organic Cations.

    PubMed

    Hucke, Anna; Ciarimboli, Giuliano

    2016-07-01

    The introduction of chemotherapy in the treatment of cancer is one of the most important achievements of modern medicine, even allowing the cure of some lethal diseases such as testicular cancer and other malignant neoplasms. The number and type of chemotherapeutic agents available have steadily increased and have developed until the introduction of targeted tumor therapy. It is now evident that transporters play an important role for determining toxicity of chemotherapeutic drugs not only against target but also against nontarget cells. This is of special importance for intracellularly active hydrophilic drugs, which cannot freely penetrate the plasma membrane. Because many important chemotherapeutic agents are substrates of transporters for organic cations, this review discusses the known interaction of these substances with these transporters. A particular focus is given to the role of transporters for organic cations in the development of side effects of chemotherapy with platinum derivatives and in the efficacy of recently developed tyrosine kinase inhibitors to specifically target cancer cells. It is evident that specific inhibition of uptake transporters may be a possible strategy to protect against undesired side effects of platinum derivatives without compromising their antitumor efficacy. These transporters are also important for efficient targeting of tyrosine kinase inhibitors to cancer cells. However, in order to achieve the aims of protecting from undesired toxicities and improving the specificity of uptake by tumor cells, an exact knowledge of transporter expression, function, regulation under normal and pathologic conditions, and of genetically and epigenetically regulation is mandatory. PMID:27385173

  13. Synthesis and characterization of transferrin-targeted chemotherapeutic delivery systems prepared via RAFT copolymerization of high molecular weight PEG macromonomers

    PubMed Central

    Roy, Debashish; Berguig, Geoffrey Y; Ghosn, Bilal; Lane, Daniel; Braswell, Scott; Stayton, Patrick S; Convertine, Anthony J

    2014-01-01

    Reversible addition-fragmentation chain transfer (RAFT) polymerization was employed to prepare a nanoparticulate drug delivery system for chemotherapeutics. The nanoparticles contain a PEG “stealth” corona as well as reactive anhydride functionality designed for conjugating targeting proteins. The multifunctional carrier functionality was achieved by controlling the copolymerization of the hydrophobic monomer lauryl methacrylate (LMA), with a reactive anhydride functional methacrylate (TMA), and a large polyethyleneglycol methacrylate monomer (Mn~950 Da) (O950). RAFT polymerization kinetics of O950 were evaluated as a function of target degrees of polymerization (DP), initial chain transfer agent to initiator ratio ([CTA]o/[I]o), and solvent concentration. Excellent control over the polymerization was observed for target DPs of 25 and 50 at [CTA]o/[I]o ratio of 10 as evidenced by narrow and symmetric molecular weight distributions and the ability to prepare block copolymers. The TMA-functional copolymers were conjugated to the tumor targeting protein transferrin (Tf). The targeted copolymer was shown to encapsulate docetaxel at concentrations comparable to the commercial single vial formulation of docetaxel (Taxotere). In vitro cytotoxicity studies conducted in HeLa cells show that the Tf targeting enhances the cancer killing properties relative to the polymer encapsulated docetaxel formulation. PMID:25221630

  14. Insight to drug delivery aspects for colorectal cancer

    PubMed Central

    Gulbake, Arvind; Jain, Aviral; Jain, Ashish; Jain, Ankit; Jain, Sanjay K

    2016-01-01

    Colorectal cancer (CRC) is the third most common cancer diagnosed worldwide in human beings. Surgery, chemotherapy, radiotherapy and targeted therapies are the conventional four approaches which are currently used for the treatment of CRC. The site specific delivery of chemotherapeutics to their site of action would increase effectiveness with reducing side effects. Targeted oral drug delivery systems based on polysaccharides are being investigated to target and deliver chemotherapeutic and chemopreventive agents directly to colon and rectum. Site-specific drug delivery to colon increases its concentration at the target site, and thus requires a lower dose and hence abridged side effects. Some novel therapies are also briefly discussed in article such as receptor (epidermal growth factor receptor, folate receptor, wheat germ agglutinin, VEGF receptor, hyaluronic acid receptor) based targeting therapy; colon targeted proapoptotic anticancer drug delivery system, gene therapy. Even though good treatment options are available for CRC, the ultimate therapeutic approach is to avert the incidence of CRC. It was also found that CRCs could be prevented by diet and nutrition such as calcium, vitamin D, curcumin, quercetin and fish oil supplements. Immunotherapy and vaccination are used nowadays which are showing better results against CRC. PMID:26811609

  15. Insight to drug delivery aspects for colorectal cancer.

    PubMed

    Gulbake, Arvind; Jain, Aviral; Jain, Ashish; Jain, Ankit; Jain, Sanjay K

    2016-01-14

    Colorectal cancer (CRC) is the third most common cancer diagnosed worldwide in human beings. Surgery, chemotherapy, radiotherapy and targeted therapies are the conventional four approaches which are currently used for the treatment of CRC. The site specific delivery of chemotherapeutics to their site of action would increase effectiveness with reducing side effects. Targeted oral drug delivery systems based on polysaccharides are being investigated to target and deliver chemotherapeutic and chemopreventive agents directly to colon and rectum. Site-specific drug delivery to colon increases its concentration at the target site, and thus requires a lower dose and hence abridged side effects. Some novel therapies are also briefly discussed in article such as receptor (epidermal growth factor receptor, folate receptor, wheat germ agglutinin, VEGF receptor, hyaluronic acid receptor) based targeting therapy; colon targeted proapoptotic anticancer drug delivery system, gene therapy. Even though good treatment options are available for CRC, the ultimate therapeutic approach is to avert the incidence of CRC. It was also found that CRCs could be prevented by diet and nutrition such as calcium, vitamin D, curcumin, quercetin and fish oil supplements. Immunotherapy and vaccination are used nowadays which are showing better results against CRC. PMID:26811609

  16. Enhanced delivery of the RAPTA-C macromolecular chemotherapeutic by conjugation to degradable polymeric micelles.

    PubMed

    Blunden, Bianca M; Lu, Hongxu; Stenzel, Martina H

    2013-12-01

    Macromolecular ruthenium complexes are a promising avenue to better and more selective chemotherapeutics. We have previously shown that RAPTA-C [RuCl2(p-cymene)(PTA)], with the water-soluble 1,3,5-phosphaadamantane (PTA) ligand, could be attached to a polymer moiety via nucleophilic substitution of an available iodide with an amide in the PTA ligand. To increase the cell uptake of this macromolecule, we designed an amphiphilic block copolymer capable of self-assembling into polymeric micelles. The block copolymer was prepared by ring-opening polymerization of d,l-lactide (3,6-dimethyl-1,4-dioxane-2,5-dione) using a RAFT agent with an additional hydroxyl functionality, followed by the RAFT copolymerization of 2-hydroxyethyl acrylate (HEA) and 2-chloroethyl methacrylate (CEMA). The Finkelstein reaction and reaction with PTA led to polymers that can readily react with the dimer of RuCl2(p-cymene) to create a macromolecular RAPTA-C drug. RAPTA-C conjugation, micellization, and subsequent cytotoxicity and cell uptake of these polymeric moieties was tested on ovarian cancer A2780, A2780cis, and Ovcar-3 cell lines. Confocal microscopy images confirmed cell uptake of the micelles into the lysosome of the cells, indicative of an endocytic pathway. On average, a 10-fold increase in toxicity was found for the macromolecular drugs when compared to the RAPTA-C molecule. Furthermore, the cell uptake of ruthenium was analyzed and a significant increase was found for the micelles compared to RAPTA-C. Notably, micelles prepared from the polymer containing fewer HEA units had the highest cytotoxicity, the best cell uptake of ruthenium and were highly effective in suppressing the colony-forming ability of cells. PMID:24266669

  17. Targeted drug delivery using genetically engineered diatom biosilica.

    PubMed

    Delalat, Bahman; Sheppard, Vonda C; Rasi Ghaemi, Soraya; Rao, Shasha; Prestidge, Clive A; McPhee, Gordon; Rogers, Mary-Louise; Donoghue, Jacqueline F; Pillay, Vinochani; Johns, Terrance G; Kröger, Nils; Voelcker, Nicolas H

    2015-01-01

    The ability to selectively kill cancerous cell populations while leaving healthy cells unaffected is a key goal in anticancer therapeutics. The use of nanoporous silica-based materials as drug-delivery vehicles has recently proven successful, yet production of these materials requires costly and toxic chemicals. Here we use diatom microalgae-derived nanoporous biosilica to deliver chemotherapeutic drugs to cancer cells. The diatom Thalassiosira pseudonana is genetically engineered to display an IgG-binding domain of protein G on the biosilica surface, enabling attachment of cell-targeting antibodies. Neuroblastoma and B-lymphoma cells are selectively targeted and killed by biosilica displaying specific antibodies sorbed with drug-loaded nanoparticles. Treatment with the same biosilica leads to tumour growth regression in a subcutaneous mouse xenograft model of neuroblastoma. These data indicate that genetically engineered biosilica frustules may be used as versatile 'backpacks' for the targeted delivery of poorly water-soluble anticancer drugs to tumour sites. PMID:26556723

  18. Protein nanocages for self-triggered nuclear delivery of DNA-targeted chemotherapeutics in Cancer Cells.

    PubMed

    Bellini, Michela; Mazzucchelli, Serena; Galbiati, Elisabetta; Sommaruga, Silvia; Fiandra, Luisa; Truffi, Marta; Rizzuto, Maria A; Colombo, Miriam; Tortora, Paolo; Corsi, Fabio; Prosperi, Davide

    2014-12-28

    A genetically engineered apoferritin variant consisting of 24 heavy-chain subunits (HFn) was produced to achieve a cumulative delivery of an antitumor drug, which exerts its cytotoxic action by targeting the DNA at the nucleus of human cancer cells with subcellular precision. The rationale of our approach is based on exploiting the natural arsenal of defense of cancer cells to stimulate them to recruit large amounts of HFn nanoparticles loaded with doxorubicin inside their nucleus in response to a DNA damage, which leads to a programmed cell death. After demonstrating the selectivity of HFn for representative cancer cells compared to healthy fibroblasts, doxorubicin-loaded HFn was used to treat the cancer cells. The results from confocal microscopy and DNA damage assays proved that loading of doxorubicin in HFn nanoparticles increased the nuclear delivery of the drug, thus enhancing doxorubicin efficacy. Doxorubicin-loaded HFn acts as a "Trojan Horse": HFn was internalized in cancer cells faster and more efficiently compared to free doxorubicin, then promptly translocated into the nucleus following the DNA damage caused by the partial release in the cytoplasm of encapsulated doxorubicin. This self-triggered translocation mechanism allowed the drug to be directly released in the nuclear compartment, where it exerted its toxic action. This approach was reliable and straightforward providing an antiproliferative effect with high reproducibility. The particular self-assembling nature of HFn nanocage makes it a versatile and tunable nanovector for a broad range of molecules suitable both for detection and treatment of cancer cells. PMID:25312541

  19. New chemotherapeutic drug sensitivity assay for colon carcinomas in monolayer culture.

    PubMed

    Schroy, P C; Cohen, A; Winawer, S J; Friedman, E A

    1988-06-01

    Ten previously untreated colon carcinomas were tested for chemotherapeutic drug sensitivity in primary monolayer culture. Colon carcinomas were partly digested to groups of epithelial cells which plated with a mean efficiency of 42 +/- 9% (SE) on a collagen I-bovine serum albumin substrate in serum-free medium, producing patches of tightly adherent epithelial cells. The cultured cells were judged epithelial by the presence of cytokeratins, an epithelial cell surface epitope, junctional complexes, and brush borders. Each carcinoma was plated in 40 to 60 Petri dishes (35 mm), yielding a mean of 28 +/- 8 (SE) colonies per dish (6832 +/- 1952 cells). Drugs tested in duplicate plates were mitomycin C, cisplatin, streptozotocin, and 5-fluorouracil at 0.1, 1, 10, and 100 micrograms/ml, and at 0.1, 1, and 2x the peak tolerated drug concentration in serum. Twenty-four h after plating, any nonadherent cells were removed, and the adherent tumor cells were continuously exposed to the drugs for 3 days. Each drug induced colony lysis in a dose-dependent manner in responsive tumors. Drug-resistant, cycling cells were identified by [3H]thymidine incorporation in colonies which were not lysed by drug treatment. Each of the ten carcinomas exhibited inherent resistance to one or more chemotherapy drugs within the concentration ranges clinically achievable. PMID:2966672

  20. Drug-eluting microarrays to identify effective chemotherapeutic combinations targeting patient-derived cancer stem cells

    PubMed Central

    Carstens, Matthew R.; Fisher, Robert C.; Acharya, Abhinav P.; Butterworth, Elizabeth A.; Scott, Edward; Huang, Emina H.; Keselowsky, Benjamin G.

    2015-01-01

    A new paradigm in oncology establishes a spectrum of tumorigenic potential across the heterogeneous phenotypes within a tumor. The cancer stem cell hypothesis postulates that a minute fraction of cells within a tumor, termed cancer stem cells (CSCs), have a tumor-initiating capacity that propels tumor growth. An application of this discovery is to target this critical cell population using chemotherapy; however, the process of isolating these cells is arduous, and the rarity of CSCs makes it difficult to test potential drug candidates in a robust fashion, particularly for individual patients. To address the challenge of screening drug libraries on patient-derived populations of rare cells, such as CSCs, we have developed a drug-eluting microarray, a miniaturized platform onto which a minimal quantity of cells can adhere and be exposed to unique treatment conditions. Hundreds of drug-loaded polymer islands acting as drug depots colocalized with adherent cells are surrounded by a nonfouling background, creating isolated culture environments on a solid substrate. Significant results can be obtained by testing <6% of the cells required for a typical 96-well plate. Reliability was demonstrated by an average coefficient of variation of 14% between all of the microarrays and 13% between identical conditions within a single microarray. Using the drug-eluting array, colorectal CSCs isolated from two patients exhibited unique responses to drug combinations when cultured on the drug-eluting microarray, highlighting the potential as a prognostic tool to identify personalized chemotherapeutic regimens targeting CSCs. PMID:26124098

  1. Nanoparticles for Brain Drug Delivery

    PubMed Central

    Masserini, Massimo

    2013-01-01

    The central nervous system, one of the most delicate microenvironments of the body, is protected by the blood-brain barrier (BBB) regulating its homeostasis. BBB is a highly complex structure that tightly regulates the movement of ions of a limited number of small molecules and of an even more restricted number of macromolecules from the blood to the brain, protecting it from injuries and diseases. However, the BBB also significantly precludes the delivery of drugs to the brain, thus, preventing the therapy of a number of neurological disorders. As a consequence, several strategies are currently being sought after to enhance the delivery of drugs across the BBB. Within this review, the recently born strategy of brain drug delivery based on the use of nanoparticles, multifunctional drug delivery systems with size in the order of one-billionth of meters, is described. The review also includes a brief description of the structural and physiological features of the barrier and of the most utilized nanoparticles for medical use. Finally, the potential neurotoxicity of nanoparticles is discussed, and future technological approaches are described. The strong efforts to allow the translation from preclinical to concrete clinical applications are worth the economic investments. PMID:25937958

  2. The role of MAPK pathways in the action of chemotherapeutic drugs.

    PubMed

    Boldt, Simone; Weidle, Ulrich H; Kolch, Walter

    2002-11-01

    In this study we have investigated the role of mitogen-induced and stress-activated MAP kinase pathways in the cellular response to taxol, etoposide and ceramide in three different human cancer cell lines: HeLa cervical carcinoma, MCF7 breast cancer and A431 squamous carcinoma cells. The mitogen-induced ERK MAPKs were linked to cell proliferation and survival, whereas the stress-activated MAPKs, p38 and JNK, were connected with apoptosis. Our results show that all drugs activated MAPKs, but that the extent and kinetics of activation were different. In order to assay the biological consequences of drug-induced MAPK activation we employed selective MAPK inhibitors and measured both long-term clonogenic survival as well as short-term parameters including apoptosis, mitochondrial metabolic integrity and cell cycle progression. Our results show that drug induced toxicity is not correlated with any singular parameter, but rather a combination of effects on cell cycle and apoptosis. In certain constellations the modulation of MAPK pathways could enhance or decrease drug efficacies. These effects mainly pertained to the regulation of apoptosis and clonogenic survival, but they were highly dependent on the combination of drug and cell line without any clear patterns of correlations emerging. These results suggest that the modulation of MAPK pathways to enhance the efficacy of chemotherapeutic drugs is of limited value unless it is tailored to the specific combination of drug and cancer. PMID:12419831

  3. Mucoadhesive vaginal drug delivery systems.

    PubMed

    Acartürk, Füsun

    2009-11-01

    Vaginal delivery is an important route of drug administration for both local and systemic diseases. The vaginal route has some advantages due to its large surface area, rich blood supply, avoidance of the first-pass effect, relatively high permeability to many drugs and self-insertion. The traditional commercial preparations, such as creams, foams, gels, irrigations and tablets, are known to reside in the vaginal cavity for a relatively short period of time owing to the self-cleaning action of the vaginal tract, and often require multiple daily doses to ensure the desired therapeutic effect. The vaginal route appears to be highly appropriate for bioadhesive drug delivery systems in order to retain drugs for treating largely local conditions, or for use in contraception. In particular, protection against sexually-transmitted diseases is critical. To prolong the residence time in the vaginal cavity, bioadhesive therapeutic systems have been developed in the form of semi-solid and solid dosage forms. The most commonly used mucoadhesive polymers that are capable of forming hydrogels are synthetic polyacrylates, polycarbophil, chitosan, cellulose derivatives (hydroxyethycellulose, hydroxy-propylcellulose and hydroxypropylmethylcellulose), hyaluronic acid derivatives, pectin, tragacanth, carrageenan and sodium alginate. The present article is a comprehensive review of the patents related to mucoadhesive vaginal drug delivery systems. PMID:19925443

  4. Pathways of cardiac toxicity: comparison between chemotherapeutic drugs doxorubicin and mitoxantrone.

    PubMed

    Damiani, Roberto Marques; Moura, Dinara Jaqueline; Viau, Cassiana Macagnan; Caceres, Rafael Andrade; Henriques, João Antonio Pêgas; Saffi, Jenifer

    2016-09-01

    Anthracyclines, e.g., doxorubicin (DOX), and anthracenediones, e.g., mitoxantrone (MTX), are drugs used in the chemotherapy of several cancer types, including solid and non-solid malignancies such as breast cancer, leukemia, lymphomas, and sarcomas. Although they are effective in tumor therapy, treatment with these two drugs may lead to side effects such as arrhythmia and heart failure. At the same clinically equivalent dose, MTX causes slightly reduced cardiotoxicity compared with DOX. These drugs interact with iron to generate reactive oxygen species (ROS), target topoisomerase 2 (Top2), and impair mitochondria. These are some of the mechanisms through which these drugs induce late cardiomyopathy. In this review, we compare the cardiotoxicities of these two chemotherapeutic drugs, DOX and MTX. As described here, even though they share similarities in their modes of toxicant action, DOX and MTX seem to differ in a key aspect. DOX is a more redox-interfering drug, while MTX induces energy imbalance. In addition, DOX toxicity can be explained by underlying mechanisms that include targeting of Top2 beta, mitochondrial impairment, and increases in ROS generation. These modes of action have not yet been demonstrated for MTX, and this knowledge gap needs to be filled. PMID:27342245

  5. Microfabricated injectable drug delivery system

    DOEpatents

    Krulevitch, Peter A.; Wang, Amy W.

    2002-01-01

    A microfabricated, fully integrated drug delivery system capable of secreting controlled dosages of multiple drugs over long periods of time (up to a year). The device includes a long and narrow shaped implant with a sharp leading edge for implantation under the skin of a human in a manner analogous to a sliver. The implant includes: 1) one or more micromachined, integrated, zero power, high and constant pressure generating osmotic engine; 2) low power addressable one-shot shape memory polymer (SMP) valves for switching on the osmotic engine, and for opening drug outlet ports; 3) microfabricated polymer pistons for isolating the pressure source from drug-filled microchannels; 4) multiple drug/multiple dosage capacity, and 5) anisotropically-etched, atomically-sharp silicon leading edge for penetrating the skin during implantation. The device includes an externally mounted controller for controlling on-board electronics which activates the SMP microvalves, etc. of the implant.

  6. Nanostructures for protein drug delivery.

    PubMed

    Pachioni-Vasconcelos, Juliana de Almeida; Lopes, André Moreni; Apolinário, Alexsandra Conceição; Valenzuela-Oses, Johanna Karina; Costa, Juliana Souza Ribeiro; Nascimento, Laura de Oliveira; Pessoa, Adalberto; Barbosa, Leandro Ramos Souza; Rangel-Yagui, Carlota de Oliveira

    2016-02-01

    Use of nanoscale devices as carriers for drugs and imaging agents has been extensively investigated and successful examples can already be found in therapy. In parallel, recombinant DNA technology together with molecular biology has opened up numerous possibilities for the large-scale production of many proteins of pharmaceutical interest, reflecting in the exponentially growing number of drugs of biotechnological origin. When we consider protein drugs, however, there are specific criteria to take into account to select adequate nanostructured systems as drug carriers. In this review, we highlight the main features, advantages, drawbacks and recent developments of nanostructures for protein encapsulation, such as nanoemulsions, liposomes, polymersomes, single-protein nanocapsules and hydrogel nanoparticles. We also discuss the importance of nanoparticle stabilization, as well as future opportunities and challenges in nanostructures for protein drug delivery. PMID:26580477

  7. Nanothermodynamics mediates drug delivery.

    PubMed

    Stefi, Aikaterina L; Sarantopoulou, Evangelia; Kollia, Zoe; Spyropoulos-Antonakakis, Nikolaos; Bourkoula, Athanasia; Petrou, Panagiota S; Kakabakos, Sotirios; Soras, Georgios; Trohopoulos, Panagiotis N; Nizamutdinov, Alexey S; Semashko, Vadim V; Cefalas, Alkiviadis Constantinos

    2015-01-01

    The efficiency of penetration of nanodrugs through cell membranes imposes further complexity due to nanothermodynamic and entropic potentials at interfaces. Action of nanodrugs is effective after cell membrane penetration. Contrary to diffusion of water diluted common molecular drugs, nanosize imposes an increasing transport complexity at boundaries and interfaces (e.g., cell membrane). Indeed, tiny dimensional systems brought the concept of "nanothermodynamic potential," which is proportional to the number of nanoentities in a macroscopic system, from either the presence of surface and edge effects at the boundaries of nanoentities or the restriction of the translational and rotational degrees of freedom of molecules within them. The core element of nanothermodynamic theory is based on the assumption that the contribution of a nanosize ensemble to the free energy of a macroscopic system has its origin at the excess interaction energy between the nanostructured entities. As the size of a system is increasing, the contribution of the nanothermodynamic potential to the free energy of the system becomes negligible. Furthermore, concentration gradients at boundaries, morphological distribution of nanoentities, and restriction of the translational motion from trapping sites are the source of strong entropic potentials at the interfaces. It is evident therefore that nanothermodynamic and entropic potentials either prevent or allow enhanced concentration very close to interfaces and thus strongly modulate nanoparticle penetration within the intracellular region. In this work, it is shown that nano-sized polynuclear iron (III)-hydroxide in sucrose nanoparticles have a nonuniform concentration around the cell membrane of macrophages in vivo, compared to uniform concentration at hydrophobic prototype surfaces. The difference is attributed to the presence of entropic and nanothermodynamic potentials at interfaces. PMID:25416996

  8. Protease-mediated drug delivery

    NASA Astrophysics Data System (ADS)

    Dickson, Eva F.; Goyan, Rebecca L.; Kennedy, James C.; Mackay, M.; Mendes, M. A. K.; Pottier, Roy H.

    2003-12-01

    Drugs used in disease treatment can cause damage to both malignant and normal tissue. This toxicity limits the maximum therapeutic dose. Drug targeting is of high interest to increase the therapeutic efficacy of the drug without increasing systemic toxicity. Certain tissue abnormalities, disease processes, cancers, and infections are characterized by high levels of activity of specific extracellular and/or intracellular proteases. Abnormally high activity levels of specific proteases are present at sites of physical or chemical trauma, blood clots, malignant tumors, rheumatoid arthritis, inflammatory bowel disease, gingival disease, glomerulonerphritis, and acute pancreatitis. Abnormal protease activity is suspected in development of liver thrombosis, pulmonary emphysema, atherosclerosis, and muscular dystrophy. Inactiviating disease-associated proteases by the administration of appropriate protease inhibitors has had limited success. Instead, one could use such proteases to target drugs to treat the condition. Protease mediated drug delivery offers such a possibility. Solubilizing groups are attached to insoluble drugs via a polypeptide chain which is specifically cleavable by certian proteases. When the solubilized drug enounters the protease, the solubilizing moieties are cleaved, and the drug precipitates at the disease location. Thus, a smaller systemic dosage could result in a therapeutic drug concentration at the treatment site with less systemic toxicity.

  9. Sildenafil reverses ABCB1- and ABCG2-mediated chemotherapeutic drug resistance

    PubMed Central

    Shi, Zhi; Tiwari, Amit K; Shukla, Suneet; Robey, Robert W.; Singh, Satyakam; Kim, In-Wha; Bates, Susan E.; Peng, Xingxiang; Abraham, Ioana; Ambudkar, Suresh V.; Talele, Tanaji T.; Fu, Li-Wu; Chen, Zhe-Sheng

    2011-01-01

    Sildenafil is a potent and selective inhibitor of the type 5 cGMP-specific phosphodiesterase that is used clinically to treat erectile dysfunction and pulmonary arterial hypertension. Here we report that sildenafil has differential effects on cell surface ABC transporters such as ABCB1, ABCC1 and ABCG2 that modulate intracompartmental and intracellular concentrations of chemotherapeutic drugs. In ABCB1-overexpressing cells, non-toxic doses of sildenafil inhibited resistance and increased the effective intracellular concentration of ABCB1 substrate drugs, such as paclitaxel. Similarly, in ABCG2-overexpressing cells, sildenafil inhibited resistance to ABCG2 substrate anticancer drugs, for example, increasing the effective intracellular concentration of mitoxantrone or the fluorescent compound BODIPY-prazosin. Sildenafil also moderately inhibited the transport of E217βG and methotrexate by the ABCG2 transporter. Mechanistic investigations revealed that sildenafil stimulated ABCB1 ATPase activity and inhibited photolabeling of ABCB1 with [125I]-IAAP, whereas it only slightly stimulated ABCG2 ATPase activity and inhibited photolabeling of ABCG2 with [125I]-IAAP. In contrast, Sildenafil did not alter the sensitivity of parental, ABCB1- or ABCG2-overexpressing cells to non-ABCB1 and non-ABCG2 substrate drugs, nor did sildenafil affect the function of another ABC drug transporter ABCC1. Homology modeling predicted the binding conformation of sildenafil within the large cavity of the transmembrane region of ABCB1. Overall, we found that sildenafil inhibits the transporter function of ABCB1 and ABCG2, with a stronger effect on ABCB1. Our findings suggest a possible strategy to enhance the distribution and potentially the activity of anti-cancer drugs by jointly using a clinically approved drug with known side effects and drug-drug interactions. PMID:21402712

  10. Sildenafil reverses ABCB1- and ABCG2-mediated chemotherapeutic drug resistance.

    PubMed

    Shi, Zhi; Tiwari, Amit K; Shukla, Suneet; Robey, Robert W; Singh, Satyakam; Kim, In-Wha; Bates, Susan E; Peng, Xingxiang; Abraham, Ioana; Ambudkar, Suresh V; Talele, Tanaji T; Fu, Li-Wu; Chen, Zhe-Sheng

    2011-04-15

    Sildenafil is a potent and selective inhibitor of the type 5 cGMP (cyclic guanosine 3',5'-monophosphate)-specific phosphodiesterase that is used clinically to treat erectile dysfunction and pulmonary arterial hypertension. Here, we report that sildenafil has differential effects on cell surface ABC transporters such as ABCB1, ABCC1, and ABCG2 that modulate intracompartmental and intracellular concentrations of chemotherapeutic drugs. In ABCB1-overexpressing cells, nontoxic doses of sildenafil inhibited resistance and increased the effective intracellular concentration of ABCB1 substrate drugs such as paclitaxel. Similarly, in ABCG2-overexpressing cells, sildenafil inhibited resistance to ABCG2 substrate anticancer drugs, for example, increasing the effective intracellular concentration of mitoxantrone or the fluorescent compound BODIPY-prazosin. Sildenafil also moderately inhibited the transport of E(2)17βG and methotrexate by the ABCG2 transporter. Mechanistic investigations revealed that sildenafil stimulated ABCB1 ATPase activity and inhibited photolabeling of ABCB1 with [(125)I]-iodoarylazidoprazosin (IAAP), whereas it only slightly stimulated ABCG2 ATPase activity and inhibited photolabeling of ABCG2 with [(125)I]-IAAP. In contrast, sildenafil did not alter the sensitivity of parental, ABCB1-, or ABCG2-overexpressing cells to non-ABCB1 and non-ABCG2 substrate drugs, nor did sildenafil affect the function of another ABC drug transporter, ABCC1. Homology modeling predicted the binding conformation of sildenafil within the large cavity of the transmembrane region of ABCB1. Overall, we found that sildenafil inhibits the transporter function of ABCB1 and ABCG2, with a stronger effect on ABCB1. Our findings suggest a possible strategy to enhance the distribution and potentially the activity of anticancer drugs by jointly using a clinically approved drug with known side effects and drug-drug interactions. PMID:21402712

  11. Targeting the sphingolipid metabolism to defeat pancreatic cancer cell resistance to the chemotherapeutic gemcitabine drug.

    PubMed

    Guillermet-Guibert, Julie; Davenne, Lise; Pchejetski, Dimitri; Saint-Laurent, Nathalie; Brizuela, Leyre; Guilbeau-Frugier, Céline; Delisle, Marie-Bernadette; Cuvillier, Olivier; Susini, Christiane; Bousquet, Corinne

    2009-04-01

    Defeating pancreatic cancer resistance to the chemotherapeutic drug gemcitabine remains a challenge to treat this deadly cancer. Targeting the sphingolipid metabolism for improving tumor chemosensitivity has recently emerged as a promising strategy. The fine balance between intracellular levels of the prosurvival sphingosine-1-phosphate (S1P) and the proapoptotic ceramide sphingolipids determines cell fate. Among enzymes that control this metabolism, sphingosine kinase-1 (SphK1), a tumor-associated protein overexpressed in many cancers, favors survival through S1P production, and inhibitors of SphK1 are used in ongoing clinical trials to sensitize epithelial ovarian and prostate cancer cells to various chemotherapeutic drugs. We here report that the cellular ceramide/S1P ratio is a critical biosensor for predicting pancreatic cancer cell sensitivity to gemcitabine. A low level of the ceramide/S1P ratio, associated with a high SphK1 activity, correlates with a robust intrinsic pancreatic cancer cell chemoresistance toward gemcitabine. Strikingly, increasing the ceramide/S1P ratio, by using pharmacologic (SphK1 inhibitor or ceramide analogue) or small interfering RNA-based approaches to up-regulate intracellular ceramide levels or reduce SphK1 activity, sensitized pancreatic cancer cells to gemcitabine. Conversely, decreasing the ceramide/S1P ratio, by up-regulating SphK1 activity, promoted gemcitabine resistance in these cells. Development of novel pharmacologic strategies targeting the sphingolipid metabolism might therefore represent an interesting promising approach, when combined with gemcitabine, to defeat pancreatic cancer chemoresistance to this drug. PMID:19372554

  12. Role of Cytochrome P450 Monooxygenase in Carcinogen and Chemotherapeutic Drug Metabolism.

    PubMed

    Wahlang, B; Falkner, K Cameron; Cave, Matt C; Prough, Russell A

    2015-01-01

    The purpose of this chapter is to provide insight into which human cytochromes P450 (CYPs) may be involved in metabolism of chemical carcinogens and anticancer drugs. A historical overview of this field and the development of literature using relevant animal models and expressed human CYPs have provided information about which specific CYPs may be involved in carcinogen metabolism. Definition of the biochemical properties of CYP activity came from several groups who studied the reaction stoichiometry of butter yellow and benzo[α]pyrene, including their role in induction of these enzyme systems. This chapter will list as much as is known about the human CYPs involved in carcinogen and anticancer drug metabolism, as well as summarize studies with rodent CYPs. A review of three major classes of anticancer drugs and their metabolism in humans is covered for cyclophosphamide, procarbazine, and anthracycline antibiotics, cancer chemotherapeutic compounds extensively metabolized by CYPs. The emerging information about human CYP gene polymorphisms as well as other enzymes involved in foreign compound metabolism provides considerable information about how these genetic variants affect carcinogen and anticancer drug metabolism. With information available from individual's genomic sequences, consideration of populations who may be at risk due to environmental exposure to carcinogens or how to optimize their cancer therapy regimens to enhance efficacy of the anticancer drugs appears to be an important field of study to benefit individuals in the future. PMID:26233902

  13. Peptide and protein delivery using new drug delivery systems.

    PubMed

    Jain, Ashish; Jain, Aviral; Gulbake, Arvind; Shilpi, Satish; Hurkat, Pooja; Jain, Sanjay K

    2013-01-01

    Pharmaceutical and biotechnological research sorts protein drug delivery systems by importance based on their various therapeutic applications. The effective and potent action of the proteins/peptides makes them the drugs of choice for the treatment of numerous diseases. Major research issues in protein delivery include the stabilization of proteins in delivery devices and the design of appropriate target-specific protein carriers. Many efforts have been made for effective delivery of proteins/peptidal drugs through various routes of administrations for successful therapeutic effects. Nanoparticles made of biodegradable polymers such as poly lactic acid, polycaprolactone, poly(lactic-co-glycolic acid), the poly(fumaric-co-sebacic) anhydride chitosan, and modified chitosan, as well as solid lipids, have shown great potential in the delivery of proteins/peptidal drugs. Moreover, scientists also have used liposomes, PEGylated liposomes, niosomes, and aquasomes, among others, for peptidal drug delivery. They also have developed hydrogels and transdermal drug delivery systems for peptidal drug delivery. A receptor-mediated delivery system is another attractive strategy to overcome the limitation in drug absorption that enables the transcytosis of the protein across the epithelial barrier. Modification such as PEGnology is applied to various proteins and peptides of the desired protein and peptides also increases the circulating life, solubility and stability, pharmacokinetic properties, and antigenicity of protein. This review focuses on various approaches for effective protein/peptidal drug delivery, with special emphasis on insulin delivery. PMID:23662604

  14. The Targeted-liposome Delivery System of Antitumor Drugs.

    PubMed

    Wu, Wei-dang; Yi, Xiu-lin; Jiang, Li-xin; Li, Ya-zhuo; Gao, Jing; Zeng, Yong; Yi, Rong-da; Dai, Li-peng; Li, Wei; Ci, Xiao-yan; Si, Duan-yun; Liu, Chang-xiao

    2015-01-01

    The liposome delivery system has been intensively explored as novel drug delivery system (DDS) for antitumor drugs, due to its safety, selective cytotoxicity, long circulation and slow elimination in blood, which is favorable for cancer therapy. The liposome-based chemotherapeutics are used to treat a variety of cancers to enhance the therapeutic index of antitumor drugs. Here, the author reviewed the important targets for cancer therapy and the pharmacokinetic behavior of liposomal drugs in vivo, as well as the application of the targeting liposomal system in cancer therapy. Considering further application for clinical use, the great challenges of the liposome-based delivery system were also proposed as follows: 1) prepare stealth liposome with steric stabilization and further enhance the therapeutic effects and safety; 2) explore more safe clinical targets and complementary or different types of targeting liposome; 3) thirdly, more investment is needed on the research of pharmacokinetics of the elements such as the ligands (antibody), PEG and lipids of liposome delivery system as well as safety evaluation. Considering the complex process of the liposomal encapsulation drugs in vivo, the author inferred that there are maybe different forms of the encapsulation drug to be internalized by the tumor tissues at the same time and space, although there are little reports on it. PMID:26652257

  15. Ultrasound mediated nanoparticle drug delivery

    NASA Astrophysics Data System (ADS)

    Mullin, Lee B.

    Ultrasound is not only a powerful diagnostic tool, but also a promising therapeutic technology that can be used to improve localized drug delivery. Microbubble contrast agents are micron sized encapsulated gas filled bubbles that are administered intravenously. Originally developed to enhance ultrasound images, microbubbles are highly echogenic due to the gas core that provides a detectable impedance difference from the surrounding medium. The core also allows for controlled response of the microbubbles to ultrasound pulses. Microbubbles can be pushed using acoustic radiation force and ruptured using high pressures. Destruction of microbubbles can increase permeability at the cellular and vascular level, which can be advantageous for drug delivery. Advances in drug delivery methods have been seen with the introduction of nanoparticles, nanometer sized objects often carrying a drug payload. In chemotherapy, nanoparticles can deliver drugs to tumors while limiting systemic exposure due to abnormalities in tumor vasculature such large gaps between endothelial cells that allow nanoparticles to enter into the interstitial space; this is referred to as the enhanced permeability and retention (EPR) effect. However, this effect may be overestimated in many tumors. Additionally, only a small percentage of the injected dose accumulates in the tumor, which most the nanoparticles accumulating in the liver and spleen. It is hypothesized that combining the acoustic activity of an ultrasound contrast agent with the high payload and extravasation ability of a nanoparticle, localized delivery to the tumor with reduced systemic toxicity can be achieved. This method can be accomplished by either loading nanoparticles onto the shell of the microbubble or through a coadministration method of both nanoparticles and microbubbles. The work presented in this dissertation utilizes novel and commercial nanoparticle formulations, combined with microbubbles and a variety of ultrasound systems

  16. Opportunities in respiratory drug delivery.

    PubMed

    Pritchard, John N; Giles, Rachael D

    2014-12-01

    A wide range of asthma and chronic obstructive pulmonary disease products are soon to be released onto the inhaled therapies market and differentiation between these devices will help them to gain market share over their competitors. Current legislation is directing healthcare towards being more efficient and cost-effective in order to continually provide quality care despite the challenges of aging populations and fewer resources. Devices and drugs that can be differentiated by producing improved patient outcomes would, therefore, be likely to win market share. In this perspective article, the current and potential opportunities for the successful delivery and differentiation of new inhaled drug products are discussed. PMID:25531928

  17. Nasal drug delivery in humans.

    PubMed

    Bitter, Christoph; Suter-Zimmermann, Katja; Surber, Christian

    2011-01-01

    Intranasal administration is an attractive option for local and systemic delivery of many therapeutic agents. The nasal mucosa is--compared to other mucosae--easily accessible. Intranasal drug administration is noninvasive, essentially painless and particularly suited for children. Application can be performed easily by patients or by physicians in emergency settings. Intranasal drug delivery offers a rapid onset of therapeutic effects (local or systemic). Nasal application circumvents gastrointestinal degradation and hepatic first-pass metabolism of the drug. The drug, the vehicle and the application device form an undividable triad. Its selection is therefore essential for the successful development of effective nasal products. This paper discusses the feasibility and potential of intranasal administration. A series of questions regarding (a) the intended use (therapeutic considerations), (b) the drug, (c) the vehicle and (d) the application device (pharmaceutical considerations) are addressed with a view to their impact on the development of products for nasal application. Current and future trends and perspectives are discussed. PMID:21325837

  18. Pharmacokinetics of Chemotherapeutic Drugs in Pediatric Patients With Down Syndrome and Leukemia.

    PubMed

    Hefti, Erik; Blanco, Javier G

    2016-05-01

    Children with Down syndrome (DS) have a 10- to 30-fold increased risk of developing acute myeloid leukemia or acute lymphoblastic leukemia. Patients with DS and leukemia are treated with the same chemotherapeutic agents as patients without DS. Treatment regimens for pediatric leukemia comprise multiple cytotoxic drugs including methotrexate, doxorubicin, vincristine, cytarabine, and etoposide. There have been reports of increased toxicity, as well as altered therapeutic outcomes in pediatric patients with DS and leukemia. This review is focused on the pharmacokinetics of cytotoxic drugs in pediatric patients with leukemia and DS. The available literature suggests that methotrexate and thioguanine display altered pharmacokinetic parameters in pediatric patients with DS. It has been hypothesized that the variable pharmacokinetics of these drugs may contribute to the increased incidence of treatment-related toxicities seen in DS. Data from a small number of studies suggest that the pharmacokinetics of vincristine, etoposide, doxorubicin, and busulfan are similar between patients with and without DS. Definitive conclusions regarding the pharmacokinetics of cytotoxic drugs in pediatric patients with leukemia and DS are difficult to reach due to limitations in the available studies. PMID:26907658

  19. STAT3/IRF1 Pathway Activation Sensitizes Cervical Cancer Cells to Chemotherapeutic Drugs.

    PubMed

    Walch-Rückheim, Barbara; Pahne-Zeppenfeld, Jennifer; Fischbach, Jil; Wickenhauser, Claudia; Horn, Lars Christian; Tharun, Lars; Büttner, Reinhard; Mallmann, Peter; Stern, Peter; Kim, Yoo-Jin; Bohle, Rainer Maria; Rübe, Christian; Ströder, Russalina; Juhasz-Böss, Ingolf; Solomayer, Erich-Franz; Smola, Sigrun

    2016-07-01

    Neoadjuvant radio/chemotherapy regimens can markedly improve cervical cancer outcome in a subset of patients, while other patients show poor responses, but may encounter severe adverse effects. Thus, there is a strong need for predictive biomarkers to improve clinical management of cervical cancer patients. STAT3 is considered as a critical antiapoptotic factor in various malignancies. We therefore investigated STAT3 activation during cervical carcinogenesis and its impact on the response of cervical cancer cells to chemotherapeutic drugs. Tyr705-phosphorylated STAT3 increased from low-grade cervical intraepithelial neoplasia (CIN1) to precancerous CIN3 lesions. Notably, pTyr705-STAT3 activation significantly declined from CIN3 to invasive cancer, also when compared in the same clinical biopsy. pTyr705-STAT3 was also low or absent in cultured human cervical cancer cell lines, consistent with the in vivo expression data. Unexpectedly, IL6-type cytokine signaling inducing STAT3 activation rendered cervical cancer cells significantly more susceptible to chemotherapeutic drugs, that is, cisplatin or etoposide. This chemosensitization was STAT3-dependent and we identified IFN regulatory factor-1 (IRF1) as the STAT3-inducible mediator required for cell death enhancement. In line with these data, pTyr705-STAT3 significantly correlated with nuclear IRF1 expression in cervical cancer in vivo Importantly, high IRF1 expression in pretreatment cervical cancer biopsy cells was associated with a significantly better response to neoadjuvant radio/chemotherapy of the patients. In summary, our study has identified a key role of the STAT3/IRF1 pathway for chemosensitization in cervical cancer. Our results suggest that pretherapeutic IRF1 expression should be evaluated as a novel predictive biomarker for neoadjuvant radio/chemotherapy responses. Cancer Res; 76(13); 3872-83. ©2016 AACR. PMID:27216197

  20. Capsaicin Enhances the Drug Sensitivity of Cholangiocarcinoma through the Inhibition of Chemotherapeutic-Induced Autophagy

    PubMed Central

    Hong, Zai-Fa; Zhao, Wen-Xiu; Yin, Zhen-Yu; Xie, Cheng-Rong; Xu, Ya-Ping; Chi, Xiao-Qin; Zhang, Sheng; Wang, Xiao-Min

    2015-01-01

    Cholangiocarcinoma (CCA), a devastating cancer with a poor prognosis, is resistant to the currently available chemotherapeutic agents. Capsaicin, the major pungent ingredient found in hot red chili peppers of the genus Capsicum, suppresses the growth of several malignant cell lines. Our aims were to investigate the role and mechanism of capsaicin with respect to the sensitivity of CCA cells to chemotherapeutic agents. The effect of capsaicin on CCA tumor sensitivity to 5-fluorouracil (5-FU) was assessed in vitro in CCA cells and in vivo in a xenograft model. The drug sensitivity of QBC939 to 5-FU was significantly enhanced by capsaicin compared with either agent alone. In addition, the combination of capsaicin with 5-FU was synergistic, with a combination index (CI) < 1, and the combined treatment also suppressed tumor growth in the CCA xenograft to a greater extent than 5-FU alone. Further investigation revealed that the autophagy induced by 5-FU was inhibited by capsaicin. Moreover, the decrease in AKT and S6 phosphorylation induced by 5-FU was effectively reversed by capsaicin, indicating that capsaicin inhibits 5-FU-induced autophagy by activating the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway in CCA cells. Taken together, these results demonstrate that capsaicin may be a useful adjunct therapy to improve chemosensitivity in CCA. This effect likely occurs via PI3K/AKT/mTOR pathway activation, suggesting a promising strategy for the development of combination drugs for CCA. PMID:25933112

  1. Capsaicin Enhances the Drug Sensitivity of Cholangiocarcinoma through the Inhibition of Chemotherapeutic-Induced Autophagy.

    PubMed

    Hong, Zai-Fa; Zhao, Wen-Xiu; Yin, Zhen-Yu; Xie, Cheng-Rong; Xu, Ya-Ping; Chi, Xiao-Qin; Zhang, Sheng; Wang, Xiao-Min

    2015-01-01

    Cholangiocarcinoma (CCA), a devastating cancer with a poor prognosis, is resistant to the currently available chemotherapeutic agents. Capsaicin, the major pungent ingredient found in hot red chili peppers of the genus Capsicum, suppresses the growth of several malignant cell lines. Our aims were to investigate the role and mechanism of capsaicin with respect to the sensitivity of CCA cells to chemotherapeutic agents. The effect of capsaicin on CCA tumor sensitivity to 5-fluorouracil (5-FU) was assessed in vitro in CCA cells and in vivo in a xenograft model. The drug sensitivity of QBC939 to 5-FU was significantly enhanced by capsaicin compared with either agent alone. In addition, the combination of capsaicin with 5-FU was synergistic, with a combination index (CI) < 1, and the combined treatment also suppressed tumor growth in the CCA xenograft to a greater extent than 5-FU alone. Further investigation revealed that the autophagy induced by 5-FU was inhibited by capsaicin. Moreover, the decrease in AKT and S6 phosphorylation induced by 5-FU was effectively reversed by capsaicin, indicating that capsaicin inhibits 5-FU-induced autophagy by activating the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway in CCA cells. Taken together, these results demonstrate that capsaicin may be a useful adjunct therapy to improve chemosensitivity in CCA. This effect likely occurs via PI3K/AKT/mTOR pathway activation, suggesting a promising strategy for the development of combination drugs for CCA. PMID:25933112

  2. Development of lattice-inserted 5-Fluorouracil-hydroxyapatite nanoparticles as a chemotherapeutic delivery system.

    PubMed

    Tseng, Ching-Li; Chen, Jung-Chih; Wu, Yu-Chun; Fang, Hsu-Wei; Lin, Feng-Huei; Tang, Tzu-Piao

    2015-10-01

    Developing an effective vehicle for cancer treatment, hydroxyapatite nanoparticles were fabricated for drug delivery. When 5-Fluorouracil, a major chemoagent, is combined with hydroxyapatite nanocarriers by interclay insertion, the modified hydroxyapatite nanoparticles have superior lysosomal degradation profiles, which could be leveraged as controlled drug release. The decomposition of the hydroxyapatite nanocarriers facilitates the release of 5-Fluorouracil into the cytoplasm causing cell death. Hydroxyapatite nanoparticles with/without 5-Fluorouracil were synthesized and analyzed in this study. Their crystallization properties and chemical composition were examined by X-ray diffraction and Fourier transforms infrared spectroscopy. The 5-Fluorouracil release rate was determined by UV spectroscopy. The biocompatibility of hydroxyapatite-5-Fluorouracil extraction solution was assessed using 3T3 cells via a WST-8 assay. The effect of hydroxyapatite-5-Fluorouracil particles which directly work on the human lung adenocarcinoma (A549) cells was evaluated by a lactate dehydrogenase assay via contact cultivation. A 5-Fluorouracil-absorbed hydroxyapatite particles were also tested. Overall, hydroxyapatite-5-Fluorouracils were prepared using a co-precipitation method wherein 5-Fluorouracil was intercalated in the hydroxyapatite lattice as determined by X-ray diffraction. Energy dispersive scanning examination showed the 5-Fluorouracil content was higher in hydroxyapatite-5-Fluorouracil than in a prepared absorption formulation. With 5-Fluorouracil insertion in the lattice, the widths of the a and c axial constants of the hydroxyapatite crystal increased. The extraction solution of hydroxyapatite-5-Fluorouracil was nontoxic to 3T3 cells, in which 5-Fluorouracil was not released in a neutral phosphate buffer solution. In contrast, at a lower pH value (2.5), 5-Fluorouracil was released by the acidic decomposition of hydroxyapatite. Finally, the results of the lactate

  3. Superhydrophobic materials for drug delivery

    NASA Astrophysics Data System (ADS)

    Yohe, Stefan Thomas

    Superhydrophobicity is a property of material surfaces reflecting the ability to maintain air at the solid-liquid interface when in contact with water. These surfaces have characteristically high apparent contact angles, by definition exceeding 150°, as a result of the composite material-air surface formed under an applied water droplet. Superhydrophobic surfaces were first discovered on naturally occurring substrates, and have subsequently been fabricated in the last several decades to harness these favorable surface properties for a number of emerging applications, including their use in biomedical settings. This work describes fabrication and characterization of superhydrophobic 3D materials, as well as their use as drug delivery devices. Superhydrophobic 3D materials are distinct from 2D superhydrophobic surfaces in that air is maintained not just at the surface of the material, but also within the bulk. When the superhydrophobic 3D materials are submerged in water, water infiltrates slowly and continuously as a new water-air-material interface is formed with controlled displacement of air. Electrospinning and electrospraying are used to fabricate superhydrophobic 3D materials utilizing blends of the biocompatible polymers poly(epsilon-caprolactone) and poly(caprolactone-co-glycerol monostearate) (PGC-C18). PGC-C18 is significantly more hydrophobic than PCL (contact angle of 116° versus 83° for flat materials), and further additions of PGC-C18 into electrospun meshes and electrosprayed coatings affords increased stability of the entrapped air layer. For example, PCL meshes alone (500 mum thick) take 10 days to fully wet, and with 10% or 30% PGC-C18 addition wetting rates are dramatically slowed to 60% wetted by 77 days and 4% by 75 days, respectively. Stability of the superhydrophobic materials can be further probed with a variety of physio-chemical techniques, including pressure, surfactant containing solutions, and solvents of varying surface tension

  4. Carrier Deformability in Drug Delivery.

    PubMed

    Morilla, Maria Jose; Romero, Eder Lilia

    2016-01-01

    Deformability is a key property of drug carriers used to increase the mass penetration across the skin without disrupting the lipid barrier. Highly deformable vesicles proved to be more effective than conventional liposomes in delivering drugs into and across the mammalian skin upon topical non occlusive application. In the past five years, highly deformable vesicles have been used for local delivery of drugs on joint diseases, skin cancer, atopic dermatitis, would healing, psoriasis, scar treatment, fungal, bacteria and protozoa infections. Promising topical vaccination strategies rely also in this type of carriers. Here we provide an overview on the main structural and mechanical features of deformable vesicles, to finish with an extensive update on their latest preclinical applications. PMID:26675226

  5. Chemotherapeutic response to cisplatin-like drugs in human breast cancer cells probed by vibrational microspectroscopy.

    PubMed

    Batista de Carvalho, A L M; Pilling, M; Gardner, P; Doherty, J; Cinque, G; Wehbe, K; Kelley, C; Batista de Carvalho, L A E; Marques, M P M

    2016-06-23

    Studies of drug-cell interactions in cancer model systems are essential in the preclinical stage of rational drug design, which relies on a thorough understanding of the mechanisms underlying cytotoxic activity and biological effects, at a molecular level. This study aimed at applying complementary vibrational spectroscopy methods to evaluate the cellular impact of two Pt(ii) and Pd(ii) dinuclear chelates with spermine (Pt2Spm and Pd2Spm), using cisplatin (cis-Pt(NH3)2Cl2) as a reference compound. Their effects on cellular metabolism were monitored in a human triple-negative metastatic breast cancer cell line (MDA-MB-231) by Raman and synchrotron-radiation infrared microspectroscopies, for different drug concentrations (2-8 μM) at 48 h exposure. Multivariate data analysis was applied (unsupervised PCA), unveiling drug- and concentration-dependent effects: apart from discrimination between control and drug-treated cells, a clear separation was obtained for the different agents studied - mononuclear vs. polynuclear, and Pt(ii) vs. Pd(ii). Spectral biomarkers of drug action were identified, as well as the cellular response to the chemotherapeutic insult. The main effect of the tested compounds was found to be on DNA, lipids and proteins, the Pd(ii) agent having a more significant impact on proteins while its Pt(ii) homologue affected the cellular lipid content at lower concentrations, which suggests the occurrence of distinct and unconventional pathways of cytotoxicity for these dinuclear polyamine complexes. Raman and FTIR microspectroscopies were confirmed as powerful non-invasive techniques to obtain unique spectral signatures of the biochemical impact and physiological reaction of cells to anticancer agents. PMID:27063935

  6. Microspheres and Nanotechnology for Drug Delivery.

    PubMed

    Jóhannesson, Gauti; Stefánsson, Einar; Loftsson, Thorsteinn

    2016-01-01

    Ocular drug delivery to the posterior segment of the eye can be accomplished by invasive drug injections into different tissues of the eye and noninvasive topical treatment. Invasive treatment involves the risks of surgical trauma and infection, and conventional topical treatments are ineffective in delivering drugs to the posterior segment of the eye. In recent years, nanotechnology has become an ever-increasing part of ocular drug delivery. In the following, we briefly review microspheres and nanotechnology for drug delivery to the eye, including different forms of nanotechnology such as nanoparticles, microparticles, liposomes, microemulsions and micromachines. The permeation barriers and anatomical considerations linked to ocular drug delivery are discussed and a theoretical overview on drug delivery through biological membranes is given. Finally, in vitro, in vivo and human studies of x03B3;-cyclodextrin nanoparticle eyedrop suspensions are discussed as an example of nanotechnology used for drug delivery to the eye. PMID:26501994

  7. Therapeutic applications of hydrogels in oral drug delivery

    PubMed Central

    Sharpe, Lindsey A; Daily, Adam M; Horava, Sarena D; Peppas, Nicholas A

    2015-01-01

    Introduction Oral delivery of therapeutics, particularly protein-based pharmaceutics, is of great interest for safe and controlled drug delivery for patients. Hydrogels offer excellent potential as oral therapeutic systems due to inherent biocompatibility, diversity of both natural and synthetic material options and tunable properties. In particular, stimuli-responsive hydrogels exploit physiological changes along the intestinal tract to achieve site-specific, controlled release of protein, peptide and chemotherapeutic molecules for both local and systemic treatment applications. Areas covered This review provides a wide perspective on the therapeutic use of hydrogels in oral delivery systems. General features and advantages of hydrogels are addressed, with more considerable focus on stimuli-responsive systems that respond to pH or enzymatic changes in the gastrointestinal environment to achieve controlled drug release. Specific examples of therapeutics are given. Last, in vitro and in vivo methods to evaluate hydrogel performance are discussed. Expert opinion Hydrogels are excellent candidates for oral drug delivery, due to the number of adaptable parameters that enable controlled delivery of diverse therapeutic molecules. However, further work is required to more accurately simulate physiological conditions and enhance performance, which is important to achieve improved bioavailability and increase commercial interest. PMID:24848309

  8. Tocol emulsions for drug solubilization and parenteral delivery.

    PubMed

    Constantinides, Panayiotis P; Tustian, Alex; Kessler, Dean R

    2004-05-01

    Tocols represent a family of tocopherols, tocotrienols, and their derivatives, and are fundamentally derived from the simplest tocopherol, 6-hydroxy-2-methyl-2-phytylchroman, which is referred to as "tocol". The most common tocol is D-alpha-tocopherol, also known as vitamin E. Tocols can be excellent solvents for water insoluble drugs and are compatible with other cosolvents, oils and surfactants. This review highlights the major developments in the use of tocols in parenteral emulsions for drug delivery, with a focus on drug solubilization, physicochemical properties, and biopharmaceutical applications. Tocol emulsions offer an appealing alternative for the parenteral administration of poorly soluble drugs, including major chemotherapeutics such as paclitaxel. Data will be presented on solubilization of paclitaxel, a key chemotherapeutic agent, and its corresponding formulation development, toxicity, efficacy and pharmacokinetic studies in animal models and humans. The breadth of the utility of tocol-based emulsions will be discussed and examples of specific therapeutic drugs and applications will be provided. As these formulations progress further in the clinic, the therapeutic utility of tocol emulsions is anticipated to expand. PMID:15109767

  9. Ocular drug delivery systems: An overview

    PubMed Central

    Patel, Ashaben; Cholkar, Kishore; Agrahari, Vibhuti; Mitra, Ashim K

    2014-01-01

    The major challenge faced by today’s pharmacologist and formulation scientist is ocular drug delivery. Topical eye drop is the most convenient and patient compliant route of drug administration, especially for the treatment of anterior segment diseases. Delivery of drugs to the targeted ocular tissues is restricted by various precorneal, dynamic and static ocular barriers. Also, therapeutic drug levels are not maintained for longer duration in target tissues. In the past two decades, ocular drug delivery research acceleratedly advanced towards developing a novel, safe and patient compliant formulation and drug delivery devices/techniques, which may surpass these barriers and maintain drug levels in tissues. Anterior segment drug delivery advances are witnessed by modulation of conventional topical solutions with permeation and viscosity enhancers. Also, it includes development of conventional topical formulations such as suspensions, emulsions and ointments. Various nanoformulations have also been introduced for anterior segment ocular drug delivery. On the other hand, for posterior ocular delivery, research has been immensely focused towards development of drug releasing devices and nanoformulations for treating chronic vitreoretinal diseases. These novel devices and/or formulations may help to surpass ocular barriers and associated side effects with conventional topical drops. Also, these novel devices and/or formulations are easy to formulate, no/negligibly irritating, possess high precorneal residence time, sustain the drug release, and enhance ocular bioavailability of therapeutics. An update of current research advancement in ocular drug delivery necessitates and helps drug delivery scientists to modulate their think process and develop novel and safe drug delivery strategies. Current review intends to summarize the existing conventional formulations for ocular delivery and their advancements followed by current nanotechnology based formulation developments

  10. Molecular aptamers for drug delivery.

    PubMed

    Tan, Weihong; Wang, Hui; Chen, Yan; Zhang, Xiaobing; Zhu, Haizhen; Yang, Chaoyong; Yang, Ronghua; Liu, Chen

    2011-12-01

    The active targeting of drugs in a cell-, tissue- or disease-specific manner represents a potentially powerful technology with widespread applications in medicine, including the treatment of cancers. Aptamers have properties such as high affinity and specificity for targets, easy chemical synthesis and modification, and rapid tissue penetration. They have become attractive molecules in diagnostics and therapeutics rivaling and, in some cases, surpassing other molecular probes, such as antibodies. In this review, we highlight the recent progress in aptamer-mediated delivery for therapeutics and disease-targeting based on aptamer integration with a variety of nanomaterials, such as gold nanorods, DNA micelles, DNA hydrogels and carbon nanotubes. PMID:21821299

  11. Fibrin Glue as a Drug Delivery System

    PubMed Central

    Spicer, Patrick P.; Mikos, Antonios G.

    2010-01-01

    Fibrin glue has been used surgically for decades for hemostasis as well as a sealant. It has also been researched as both a gel for cell delivery and a vehicle for drug delivery. The drug delivery applications for fibrin glue span tissue engineering to chemotherapy and involve several mechanisms for drug matrix interactions and control of release kinetics. Additionally, drugs or factors can be loaded in the gel via impregnation and tethering to the gel through covalent linkages or affinity based systems. This review highlights recent research of fibrin glue as a drug delivery vehicle. PMID:20637815

  12. Repurposing the FDA-Approved Pinworm Drug Pyrvinium as a Novel Chemotherapeutic Agent for Intestinal Polyposis

    PubMed Central

    Giambelli, Camilla; Fei, Dennis Liang; Han, Lu; Hang, Brian I.; Bai, Feng; Pei, Xin-Hai; Nose, Vania; Burlingame, Oname; Capobianco, Anthony J.; Orton, Darren; Lee, Ethan; Robbins, David J.

    2014-01-01

    Mutations in the WNT-pathway regulator ADENOMATOUS POLYPOSIS COLI (APC) promote aberrant activation of the WNT pathway that is responsible for APC-associated diseases such as Familial Adenomatous Polyposis (FAP) and 85% of spontaneous colorectal cancers (CRC). FAP is characterized by multiple intestinal adenomas, which inexorably result in CRC. Surprisingly, given their common occurrence, there are few effective chemotherapeutic drugs for FAP. Here we show that the FDA-approved, anti-helminthic drug Pyrvinium attenuates the growth of WNT-dependent CRC cells and does so via activation of CK1α. Furthermore, we show that Pyrvinium can function as an in vivo inhibitor of WNT-signaling and polyposis in a mouse model of FAP: APCmin mice. Oral administration of Pyrvinium, a CK1α agonist, attenuated the levels of WNT-driven biomarkers and inhibited adenoma formation in APCmin mice. Considering its well-documented safe use for treating enterobiasis in humans, our findings suggest that Pyrvinium could be repurposed for the clinical treatment of APC-associated polyposes. PMID:25003333

  13. Modeling Expression Plasticity of Genes that Differentiate Drug-sensitive from Drug-resistant Cells to Chemotherapeutic Treatment

    PubMed Central

    Wang, Ningtao; Wang, Yaqun; Han, Hao; Huber, Kathryn J; Yang, Jin-Ming; Li, Runze; Wu, Rongling

    2014-01-01

    By measuring gene expression at an unprecedented resolution and throughput, RNA-seq has played a pivotal role in studying biological functions. Its typical application in clinical medicine is to identify the discrepancies of gene expression between two different types of cancer cells, sensitive and resistant to chemotherapeutic treatment, in a hope to predict drug response. Here we modified and used a mechanistic model to identify distinct patterns of gene expression in response of different types of breast cancer cell lines to chemotherapeutic treatment. This model was founded on a mixture likelihood of Poisson-distributed transcript read data, with each mixture component specified by the Skellam function. By estimating and comparing the amount of gene expression in each environment, the model can test how genes alter their expression in response to environment and how different genes interact with each other in the responsive process. Using the modified model, we identified the alternations of gene expression between two cell lines of breast cancer, resistant and sensitive to tamoxifen, which allows us to interpret the expression mechanism of how genes respond to metabolic differences between the two cell types. The model can have a general implication for studying the plastic pattern of gene expression across different environments measured by RNA-seq. PMID:25435798

  14. Ungual and transungual drug delivery.

    PubMed

    Shivakumar, H N; Juluri, Abhishek; Desai, B G; Murthy, S Narasimha

    2012-08-01

    Topical therapy is desirable in treatment of nail diseases like onychomycosis (fungal infection of nail) and psoriasis. The topical treatment avoids the adverse effects associated with systemic therapy, thereby enhancing the patient compliance and reducing the treatment cost. However the effectiveness of the topical therapies has been limited due to the poor permeability of the nail plate to topically applied therapeutic agents. Research over the past one decade has been focused on improving the transungual permeability by means of chemical treatment, penetration enhancers, mechanical and physical methods. The present review is an attempt to discuss the different physical and chemical methods employed to increase the permeability of the nail plate. Minimally invasive electrically mediated techniques such as iontophoresis have gained success in facilitating the transungual delivery of actives. In addition drug transport across the nail plate has been improved by filing the dorsal surface of the nail plate prior to application of topical formulation. But attempts to improve the trans-nail permeation using transdermal chemical enhancers have failed so far. Attempts are on to search suitable physical enhancement techniques and chemical transungual enhancers in view to maximize the drug delivery across the nail plate. PMID:22149347

  15. Fluorescent graphene quantum dots as traceable, pH-sensitive drug delivery systems

    PubMed Central

    Qiu, Jichuan; Zhang, Ruibin; Li, Jianhua; Sang, Yuanhua; Tang, Wei; Rivera Gil, Pilar; Liu, Hong

    2015-01-01

    Graphene quantum dots (GQDs) were rationally fabricated as a traceable drug delivery system for the targeted, pH-sensitive delivery of a chemotherapeutic drug into cancer cells. The GQDs served as fluorescent carriers for a well-known anticancer drug, doxorubicin (Dox). The whole system has the capacity for simultaneous tracking of the carrier and of drug release. Dox release is triggered upon acidification of the intracellular vesicles, where the carriers are located after their uptake by cancer cells. Further functionalization of the loaded carriers with targeting moieties such as arginine-glycine-aspartic acid (RGD) peptides enhanced their uptake by cancer cells. DU-145 and PC-3 human prostate cancer cell lines were used to evaluate the anticancer ability of Dox-loaded RGD-modified GQDs (Dox-RGD-GQDs). The results demonstrated the feasibility of using GQDs as traceable drug delivery systems with the ability for the pH-triggered delivery of drugs into target cells. PMID:26604747

  16. Polymeric conjugates for drug delivery

    PubMed Central

    Larson, Nate; Ghandehari, Hamidreza

    2012-01-01

    The field of polymer therapeutics has evolved over the past decade and has resulted in the development of polymer-drug conjugates with a wide variety of architectures and chemical properties. Whereas traditional non-degradable polymeric carriers such as poly(ethylene glycol) (PEG) and N-(2-hydroxypropyl methacrylamide) (HPMA) copolymers have been translated to use in the clinic, functionalized polymer-drug conjugates are increasingly being utilized to obtain biodegradable, stimuli-sensitive, and targeted systems in an attempt to further enhance localized drug delivery and ease of elimination. In addition, the study of conjugates bearing both therapeutic and diagnostic agents has resulted in multifunctional carriers with the potential to both “see and treat” patients. In this paper, the rational design of polymer-drug conjugates will be discussed followed by a review of different classes of conjugates currently under investigation. The design and chemistry used for the synthesis of various conjugates will be presented with additional comments on their potential applications and current developmental status. PMID:22707853

  17. Physically facilitating drug-delivery systems

    PubMed Central

    Rodriguez-Devora, Jorge I; Ambure, Sunny; Shi, Zhi-Dong; Yuan, Yuyu; Sun, Wei; Xu, Tao

    2012-01-01

    Facilitated/modulated drug-delivery systems have emerged as a possible solution for delivery of drugs of interest to pre-allocated sites at predetermined doses for predefined periods of time. Over the past decade, the use of different physical methods and mechanisms to mediate drug release and delivery has grown significantly. This emerging area of research has important implications for development of new therapeutic drugs for efficient treatments. This review aims to introduce and describe different modalities of physically facilitating drug-delivery systems that are currently in use for cancer and other diseases therapy. In particular, delivery methods based on ultrasound, electrical, magnetic and photo modulations are highlighted. Current uses and areas of improvement for these different physically facilitating drug-delivery systems are discussed. Furthermore, the main advantages and drawbacks of these technologies reviewed are compared. The review ends with a speculative viewpoint of how research is expected to evolve in the upcoming years. PMID:22485192

  18. C8-glycosphingolipids preferentially insert into tumor cell membranes and promote chemotherapeutic drug uptake.

    PubMed

    Cordeiro Pedrosa, Lília R; van Cappellen, Wiggert A; Steurer, Barbara; Ciceri, Dalila; ten Hagen, Timo L M; Eggermont, Alexander M M; Verheij, Marcel; Goñi, Felix María; Koning, Gerben A; Contreras, F-Xabier

    2015-08-01

    Insufficient drug delivery into tumor cells limits the therapeutic efficacy of chemotherapy. Co-delivery of liposome-encapsulated drug and synthetic short-chain glycosphingolipids (SC-GSLs) significantly improved drug bioavailability by enhancing intracellular drug uptake. Investigating the mechanisms underlying this SC-GSL-mediated drug uptake enhancement is the aim of this study. Fluorescence microscopy was used to visualize the cell membrane lipid transfer intracellular fate of fluorescently labeled C6-NBD-GalCer incorporated in liposomes in tumor and non-tumor cells. Additionally click chemistry was applied to image and quantify native SC-GSLs in tumor and non-tumor cell membranes. SC-GSL-mediated flip-flop was investigated in model membranes to confirm membrane-incorporation of SC-GSL and its effect on membrane remodeling. SC-GSL enriched liposomes containing doxorubicin (Dox) were incubated at 4°C and 37°C and intracellular drug uptake was studied in comparison to standard liposomes and free Dox. SC-GSL transfer to the cell membrane was independent of liposomal uptake and the majority of the transferred lipid remained in the plasma membrane. The transfer of SC-GSL was tumor cell-specific and induced membrane rearrangement as evidenced by a transbilayer flip-flop of pyrene-SM. However, pore formation was measured, as leakage of hydrophilic fluorescent probes was not observed. Moreover, drug uptake appeared to be mediated by SC-GSLs. SC-GSLs enhanced the interaction of doxorubicin (Dox) with the outer leaflet of the plasma membrane of tumor cells at 4°C. Our results demonstrate that SC-GSLs preferentially insert into tumor cell plasma membranes enhancing cell intrinsic capacity to translocate amphiphilic drugs such as Dox across the membrane via a biophysical process. PMID:25917957

  19. Novel central nervous system drug delivery systems.

    PubMed

    Stockwell, Jocelyn; Abdi, Nabiha; Lu, Xiaofan; Maheshwari, Oshin; Taghibiglou, Changiz

    2014-05-01

    For decades, biomedical and pharmaceutical researchers have worked to devise new and more effective therapeutics to treat diseases affecting the central nervous system. The blood-brain barrier effectively protects the brain, but poses a profound challenge to drug delivery across this barrier. Many traditional drugs cannot cross the blood-brain barrier in appreciable concentrations, with less than 1% of most drugs reaching the central nervous system, leading to a lack of available treatments for many central nervous system diseases, such as stroke, neurodegenerative disorders, and brain tumors. Due to the ineffective nature of most treatments for central nervous system disorders, the development of novel drug delivery systems is an area of great interest and active research. Multiple novel strategies show promise for effective central nervous system drug delivery, giving potential for more effective and safer therapies in the future. This review outlines several novel drug delivery techniques, including intranasal drug delivery, nanoparticles, drug modifications, convection-enhanced infusion, and ultrasound-mediated drug delivery. It also assesses possible clinical applications, limitations, and examples of current clinical and preclinical research for each of these drug delivery approaches. Improved central nervous system drug delivery is extremely important and will allow for improved treatment of central nervous system diseases, causing improved therapies for those who are affected by central nervous system diseases. PMID:24325540

  20. Polymers for Colon Targeted Drug Delivery

    PubMed Central

    Rajpurohit, H.; Sharma, P.; Sharma, S.; Bhandari, A.

    2010-01-01

    The colon targeted drug delivery has a number of important implications in the field of pharmacotherapy. Oral colon targeted drug delivery systems have recently gained importance for delivering a variety of therapeutic agents for both local and systemic administration. Targeting of drugs to the colon via oral administration protect the drug from degradation or release in the stomach and small intestine. It also ensures abrupt or controlled release of the drug in the proximal colon. Various drug delivery systems have been designed that deliver the drug quantitatively to the colon and then trigger the release of drug. This review will cover different types of polymers which can be used in formulation of colon targeted drug delivery systems. PMID:21969739

  1. Silica-based mesoporous nanoparticles for controlled drug delivery.

    PubMed

    Kwon, Sooyeon; Singh, Rajendra K; Perez, Roman A; Abou Neel, Ensanya A; Kim, Hae-Won; Chrzanowski, Wojciech

    2013-01-01

    Drug molecules with lack of specificity and solubility lead patients to take high doses of the drug to achieve sufficient therapeutic effects. This is a leading cause of adverse drug reactions, particularly for drugs with narrow therapeutic window or cytotoxic chemotherapeutics. To address these problems, there are various functional biocompatible drug carriers available in the market, which can deliver therapeutic agents to the target site in a controlled manner. Among the carriers developed thus far, mesoporous materials emerged as a promising candidate that can deliver a variety of drug molecules in a controllable and sustainable manner. In particular, mesoporous silica nanoparticles are widely used as a delivery reagent because silica possesses favourable chemical properties, thermal stability and biocompatibility. Currently, sol-gel-derived mesoporous silica nanoparticles in soft conditions are of main interest due to simplicity in production and modification and the capacity to maintain function of bioactive agents. The unique mesoporous structure of silica facilitates effective loading of drugs and their subsequent controlled release. The properties of mesopores, including pore size and porosity as well as the surface properties, can be altered depending on additives used to fabricate mesoporous silica nanoparticles. Active surface enables functionalisation to modify surface properties and link therapeutic molecules. The tuneable mesopore structure and modifiable surface of mesoporous silica nanoparticle allow incorporation of various classes of drug molecules and controlled delivery to the target sites. This review aims to present the state of knowledge of currently available drug delivery system and identify properties of an ideal drug carrier for specific application, focusing on mesoporous silica nanoparticles. PMID:24020012

  2. Silica-based mesoporous nanoparticles for controlled drug delivery

    PubMed Central

    Kwon, Sooyeon; Singh, Rajendra K; Perez, Roman A; Abou Neel, Ensanya A

    2013-01-01

    Drug molecules with lack of specificity and solubility lead patients to take high doses of the drug to achieve sufficient therapeutic effects. This is a leading cause of adverse drug reactions, particularly for drugs with narrow therapeutic window or cytotoxic chemotherapeutics. To address these problems, there are various functional biocompatible drug carriers available in the market, which can deliver therapeutic agents to the target site in a controlled manner. Among the carriers developed thus far, mesoporous materials emerged as a promising candidate that can deliver a variety of drug molecules in a controllable and sustainable manner. In particular, mesoporous silica nanoparticles are widely used as a delivery reagent because silica possesses favourable chemical properties, thermal stability and biocompatibility. Currently, sol-gel-derived mesoporous silica nanoparticles in soft conditions are of main interest due to simplicity in production and modification and the capacity to maintain function of bioactive agents. The unique mesoporous structure of silica facilitates effective loading of drugs and their subsequent controlled release. The properties of mesopores, including pore size and porosity as well as the surface properties, can be altered depending on additives used to fabricate mesoporous silica nanoparticles. Active surface enables functionalisation to modify surface properties and link therapeutic molecules. The tuneable mesopore structure and modifiable surface of mesoporous silica nanoparticle allow incorporation of various classes of drug molecules and controlled delivery to the target sites. This review aims to present the state of knowledge of currently available drug delivery system and identify properties of an ideal drug carrier for specific application, focusing on mesoporous silica nanoparticles. PMID:24020012

  3. Breathable Medicine: Pulmonary Mode of Drug Delivery.

    PubMed

    Gandhimathi, Chinnasamy; Venugopal, Jayarama Reddy; Sundarrajan, Subramanian; Sridhar, Radhakrishnan; Tay, Samuel Sam Wah; Ramakrishna, Seeram; Kumar, Srinivasan Dinesh

    2015-04-01

    Pharmaceutically active compounds require different modes of drug delivery systems to accomplish therapeutic activity without loss of its activity and lead to exhibit no adverse effects. Originating from ancient days, pulmonary mode of drug delivery is gaining much importance compared to other modes of drug delivery systems with respect to specific diseases. Pulmonary drug delivery is a non-invasive route for local and systemic therapies together with more patient convenience, compliance and is a needleless system. In this review, we addressed the vaccine delivery via non- or minimally invasive routes. Polymeric nanoparticles are preferred for use in the pulmonary delivery devices owing to a prolonged retention in lungs. Small site for absorption, mucociliary clearance, short residence time and low bioavailability are some of the limitations in pulmonary drug delivery have been resolved by generating micro- and nano-sized aerosol particles. We have classified the breathable medicine on the basis of available devices for inhalation and also prominent diseases treated through pulmonary mode of drug delivery. Owing to increasing toxicity of pharmacological drugs, the use of natural medicines has been rapidly gaining importance recently. The review article describes breathability of medicines or the pulmonary mode of drug delivery system and their drug release profile, absorption, distribution and efficacy to cure asthma and diabetes. PMID:26353470

  4. Drug Delivery Innovations for Enhancing the Anticancer Potential of Vitamin E Isoforms and Their Derivatives

    PubMed Central

    Neophytou, Christiana M.; Constantinou, Andreas I.

    2015-01-01

    Vitamin E isoforms have been extensively studied for their anticancer properties. Novel drug delivery systems (DDS) that include liposomes, nanoparticles, and micelles are actively being developed to improve Vitamin E delivery. Furthermore, several drug delivery systems that incorporate Vitamin E isoforms have been synthesized in order to increase the bioavailability of chemotherapeutic agents or to provide a synergistic effect. D-alpha-tocopheryl polyethylene glycol succinate (Vitamin E TPGS or TPGS) is a synthetic derivative of natural alpha-tocopherol which is gaining increasing interest in the development of drug delivery systems and has also shown promising anticancer effect as a single agent. This review provides a summary of the properties and anticancer effects of the most potent Vitamin E isoforms and an overview of the various formulations developed to improve their efficacy, with an emphasis on the use of TPGS in drug delivery approaches. PMID:26137487

  5. Interaction of standardized mistletoe (Viscum album) extracts with chemotherapeutic drugs regarding cytostatic and cytotoxic effects in vitro

    PubMed Central

    2014-01-01

    Background Given the importance of complementary and alternative medicine (CAM) to cancer patients, there is an increasing need to learn more about possible interactions between CAM and anticancer drugs. Mistletoe (Viscum album L.) belongs to the medicinal herbs that are used as supportive care during chemotherapy. In the in vitro study presented here the effect of standardized mistletoe preparations on the cytostatic and cytotoxic activity of several common conventional chemotherapeutic drugs was investigated using different cancer cell lines. Methods Human breast carcinoma cell lines HCC1937 and HCC1143 were treated with doxorubicin hydrochloride, pancreas adenocarcinoma cell line PA-TU-8902 with gemcitabine hydrochloride, prostate carcinoma cell line DU145 with docetaxel and mitoxantrone hydrochloride and lung carcinoma cell line NCI-H460 was treated with docetaxel and cisplatin. Each dose of the respective chemotherapeutic drug was combined with Viscum album extract (VAE) in clinically relevant concentrations and proliferation and apoptosis were measured. Results VAE did not inhibit chemotherapy induced cytostasis and cytotoxicity in any of our experimental settings. At higher concentrations VAE showed an additive inhibitory effect. Conclusions Our in vitro results suggest that no risk of safety by herb drug interactions has to be expected from the exposition of cancer cells to chemotherapeutic drugs and VAE simultaneously. PMID:24397864

  6. Drug delivery systems: An updated review

    PubMed Central

    Tiwari, Gaurav; Tiwari, Ruchi; Sriwastawa, Birendra; Bhati, L; Pandey, S; Pandey, P; Bannerjee, Saurabh K

    2012-01-01

    Drug delivery is the method or process of administering a pharmaceutical compound to achieve a therapeutic effect in humans or animals. For the treatment of human diseases, nasal and pulmonary routes of drug delivery are gaining increasing importance. These routes provide promising alternatives to parenteral drug delivery particularly for peptide and protein therapeutics. For this purpose, several drug delivery systems have been formulated and are being investigated for nasal and pulmonary delivery. These include liposomes, proliposomes, microspheres, gels, prodrugs, cyclodextrins, among others. Nanoparticles composed of biodegradable polymers show assurance in fulfilling the stringent requirements placed on these delivery systems, such as ability to be transferred into an aerosol, stability against forces generated during aerosolization, biocompatibility, targeting of specific sites or cell populations in the lung, release of the drug in a predetermined manner, and degradation within an acceptable period of time. PMID:23071954

  7. Simultaneous cytosolic delivery of a chemotherapeutic and siRNA using nanoparticle-stabilized nanocapsules

    NASA Astrophysics Data System (ADS)

    Hardie, Joseph; Jiang, Ying; Tetrault, Emily R.; Ghazi, Phaedra C.; Yesilbag Tonga, Gulen; Farkas, Michelle E.; Rotello, Vincent M.

    2016-09-01

    We report on nanoparticle-stabilized capsules (NPSCs) as a platform for the co-delivery of survivin-targeted siRNA and tamoxifen. These capsules feature an inner oil core that provides a carrier for tamoxifen, and is coated on the surface with positively charged nanoparticles self-assembled with siRNA. The multifaceted chemical nature of the NPSC system enables the simultaneous delivery of both payloads directly into the cytosol in vitro. The NPSC co-delivery of tamoxifen and survivin-targeted siRNA into breast cancer cells disables the pathways that inhibit apoptosis, resulting in enhanced breast cell death.

  8. Simultaneous cytosolic delivery of a chemotherapeutic and siRNA using nanoparticle-stabilized nanocapsules.

    PubMed

    Hardie, Joseph; Jiang, Ying; Tetrault, Emily R; Ghazi, Phaedra C; Tonga, Gulen Yesilbag; Farkas, Michelle E; Rotello, Vincent M

    2016-09-16

    We report on nanoparticle-stabilized capsules (NPSCs) as a platform for the co-delivery of survivin-targeted siRNA and tamoxifen. These capsules feature an inner oil core that provides a carrier for tamoxifen, and is coated on the surface with positively charged nanoparticles self-assembled with siRNA. The multifaceted chemical nature of the NPSC system enables the simultaneous delivery of both payloads directly into the cytosol in vitro. The NPSC co-delivery of tamoxifen and survivin-targeted siRNA into breast cancer cells disables the pathways that inhibit apoptosis, resulting in enhanced breast cell death. PMID:27505356

  9. Multifunctional Particles for Melanoma-Targeted Drug Delivery

    PubMed Central

    Wadajkar, Aniket S.; Bhavsar, Zarna; Ko, Cheng-Yu; Koppolu, Bhanuprasanth; Cui, Weina; Tang, Liping; Nguyen, Kytai T.

    2012-01-01

    New magnetic-based core-shell particles (MBCSP) were developed to target skin cancer cells while delivering chemotherapeutic drugs in a controlled fashion. MBCSP consist of a thermo-responsive shell of poly(N-isopropylacrylamide-acrylamide-allylamine) and a core of poly(lactic-co-glycolic acid) (PLGA) embedded with magnetite nanoparticles. To target melanoma cancer cells, MBCSP were conjugated with Gly-Arg-Gly-Asp-Ser (GRGDS) peptides that specifically bind to the α5β3+ receptor of melanoma cell. MBCSP consist of unique multifunctional and controlled drug delivery characteristics. Specially, they can provide dual drug release mechanisms (a sustained release of drugs through degradation of PLGA core and a controlled release in response to changes in temperature via thermo-responsive polymer shell), and dual targeting mechanisms (magnetic localization and receptor-mediated targeting). Results from in vitro studies indicate that GRGDS-conjugated MBCSP has an average diameter of 296 nm and exhibit no cytotoxicity towards human dermal fibroblasts up to 500 μg ml−1. Further, a sustained release of curcumin from the core and a temperature-dependent release of doxorubicin from the shell of MBCSP were observed. The particles also produced a dark contrast signal in magnetic resonance imaging. Finally, the particles were accumulated at the tumor site in a B16F10 melanoma orthotopic mouse model, especially in presence of a magnet. Results indicate great potential of MBCSP as a platform technology to target, treat, and monitor melanoma for targeted drug delivery to reduce side effects of chemotherapeutic reagents. PMID:22561668

  10. Microfluidic Manipulation of Core/Shell Nanoparticles for Oral Delivery of Chemotherapeutics: A New Treatment Approach for Colorectal Cancer.

    PubMed

    Hasani-Sadrabadi, Mohammad Mahdi; Taranejoo, Shahrouz; Dashtimoghadam, Erfan; Bahlakeh, Ghasem; Majedi, Fatemeh Sadat; VanDersarl, Jules John; Janmaleki, Mohsen; Sharifi, Fatemeh; Bertsch, Arnaud; Hourigan, Kerry; Tayebi, Lobat; Renaud, Philippe; Jacob, Karl I

    2016-06-01

    A microfluidics approach to synthesize core-shell nanocarriers with high pH tunability is described. The sacrificial shell protects the core layer with the drugs and prevents their release in the severe pH conditions of the gastrointestinal tract, while allowing for drug release in the proximity of a tumor. The proposed nanoparticulate drug-delivery system is designed for the oral administration of cancer therapeutics. PMID:27001745

  11. Molecular aptamers for drug delivery

    PubMed Central

    Tan, Weihong; Wang, Hui; Chen, Yan; Zhang, Xiaobing; Zhu, Haizhen; Yang, Chaoyong; Yang, Ronghua

    2011-01-01

    The active targeting of drugs in a cell-, tissue-, or disease-specific manner represents a potentially powerful technology with widespread applications in medicine, including the treatment of cancers. Aptamers, with properties such as high affinity and specificity to their targets, easy chemical synthesis and modification, as well as rapid tissue penetration, have become attractive molecules in diagnostics and therapeutics. They rival and, in some cases, surpass other molecular probes, such as antibodies. In this review, we highlight the recent progress in aptamer-mediated delivery for therapeutics and disease-targeting based on aptamer integration with a variety of nanomaterials, such as gold nanorods, DNA-micelles, DNA-hydrogels and carbon nanotubes. PMID:21821299

  12. Implantable Devices for Sustained, Intravesical Drug Delivery

    PubMed Central

    2016-01-01

    In clinical settings, intravesical instillation of a drug bolus is often performed for the treatment of bladder diseases. However, it requires repeated instillations to extend drug efficacy, which may result in poor patient compliance. To alleviate this challenge, implantable devices have been developed for the purpose of sustained, intravesical drug delivery. In this review, we briefly summarize the current trend in the development of intravesical drug-delivery devices. We also introduce the most recently developed devices with strong potential for intravesical drug-delivery applications. PMID:27377941

  13. Targeted Drug Delivery in Pancreatic Cancer

    PubMed Central

    Yu, Xianjun; Zhang, Yuqing; Chen, Changyi; Yao, Qizhi; Li, Min

    2009-01-01

    Effective drug delivery in pancreatic cancer treatment remains a major challenge. Because of the high resistance to chemo and radiation therapy, the overall survival rate for pancreatic cancer is extremely low. Recent advances in drug delivery systems hold great promise for improving cancer therapy. Using liposomes, nanoparticles, and carbon nanotubes to deliver cancer drugs and other therapeutic agents such as siRNA, suicide gene, oncolytic virus, small molecule inhibitor and antibody has been a success in recent pre-clinical trials. However, how to improve the specificity and stability of the delivered drug using ligand or antibody directed delivery represent a major problem. Therefore, developing novel, specific, tumor-targeted drug delivery systems is urgently needed for this terrible disease. This review summarizes the current progress on targeted drug delivery in pancreatic cancer, and provides important information on potential therapeutic targets for pancreatic cancer treatment. PMID:19853645

  14. Permeation enhancer strategies in transdermal drug delivery.

    PubMed

    Marwah, Harneet; Garg, Tarun; Goyal, Amit K; Rath, Goutam

    2016-01-01

    Today, ∼74% of drugs are taken orally and are not found to be as effective as desired. To improve such characteristics, transdermal drug delivery was brought to existence. This delivery system is capable of transporting the drug or macromolecules painlessly through skin into the blood circulation at fixed rate. Topical administration of therapeutic agents offers many advantages over conventional oral and invasive techniques of drug delivery. Several important advantages of transdermal drug delivery are prevention from hepatic first pass metabolism, enhancement of therapeutic efficiency and maintenance of steady plasma level of the drug. Human skin surface, as a site of drug application for both local and systemic effects, is the most eligible candidate available. New controlled transdermal drug delivery systems (TDDS) technologies (electrically-based, structure-based and velocity-based) have been developed and commercialized for the transdermal delivery of troublesome drugs. This review article covers most of the new active transport technologies involved in enhancing the transdermal permeation via effective drug delivery system. PMID:25006687

  15. Enhanced anticancer efficacy by ATP-mediated liposomal drug delivery.

    PubMed

    Mo, Ran; Jiang, Tianyue; Gu, Zhen

    2014-06-01

    A liposome-based co-delivery system composed of a fusogenic liposome encapsulating ATP-responsive elements with chemotherapeutics and a liposome containing ATP was developed for ATP-mediated drug release triggered by liposomal fusion. The fusogenic liposome had a protein-DNA complex core containing an ATP-responsive DNA scaffold with doxorubicin (DOX) and could release DOX through a conformational change from the duplex to the aptamer/ATP complex in the presence of ATP. A cell-penetrating peptide-modified fusogenic liposomal membrane was coated on the core, which had an acid-triggered fusogenic potential with the ATP-loaded liposomes or endosomes/lysosomes. Directly delivering extrinsic liposomal ATP promoted the drug release from the fusogenic liposome in the acidic intracellular compartments upon a pH-sensitive membrane fusion and anticancer efficacy was enhanced both in vitro and in vivo. PMID:24764317

  16. Development of an Acoustic Droplet Vaporization, Ultrasound Drug Delivery Emulsion

    NASA Astrophysics Data System (ADS)

    Fabiilli, Mario L.; Sebastian, Ian E.; Fowlkes, J. Brian

    2010-03-01

    Many therapeutic applications of ultrasound (US) include the use of pefluorocarbon (PFC) microbubbles or emulsions. These colloidal systems can be activated in the presence of US, which in the case of emulsions, results in the production of bubbles—a process known as acoustic droplet vaporization (ADV). ADV can be used as a drug delivery mechanism, thereby yielding the localized release of toxic agents such a chemotherapeutics. In this work, emulsions that contain PFC and chlorambucil, a chemotherapy drug, are formulated using albumin or lipid shells. For albumin droplets, the oil phase—which contained CHL—clearly enveloped the PFC phase. The albumin emulsion also displayed better retention of CHL in the absence of US, which was evaluated by incubating Chinese hamster ovary cells with the various formulations. Thus, the developed emulsions are suitable for further testing in ADV-induced release of CHL.

  17. Ultrasound-triggered drug delivery using acoustic droplet vaporization

    NASA Astrophysics Data System (ADS)

    Fabiilli, Mario Leonardo

    The goal of targeted drug delivery is the spatial and temporal localization of a therapeutic agent and its associated bioeffects. One method of drug localization is acoustic droplet vaporization (ADV), whereby drug-laden perfluorocarbon (PFC) emulsions are vaporized into gas bubbles using ultrasound, thereby releasing drug locally. Transpulmonary droplets are converted into bubbles that occlude capillaries, sequestering the released drug within an organ or tumor. This research investigates the relationship between the ADV and inertial cavitation (IC) thresholds---relevant for drug delivery due to the bioffects generated by IC---and explores the delivery of lipophilic and hydrophilic compounds using PFC double emulsions. IC can positively and negatively affect ultrasound mediated drug delivery. The ADV and IC thresholds were determined for various bulk fluid, droplet, and acoustic parameters. At 3.5 MHz, the ADV threshold occurred at a lower rarefactional pressure than the IC threshold. The results suggest that ADV is a distinct phenomenon from IC, the ADV nucleus is internal to the droplet, and the IC nucleus is the bubble generated by ADV. The ADV triggered release of a lipophilic chemotherapeutic agent, chlorambucil (CHL), from a PFC-in-oil-in-water emulsion was explored using plated cells. Cells exposed to a CHL-loaded emulsion, without ADV, displayed 44% less growth inhibition than cells exposed to an equal concentration of CHL in solution. Upon ADV of the CHL-loaded emulsion, the growth inhibition increased to the same level as cells exposed to CHL in solution. A triblock copolymer was synthesized which enabled the formulation of stable water-in-PFC-in-water (W1/PFC/W2) emulsions. The encapsulation of fluorescein in the W1 phase significantly decreased the mass flux of fluorescein; ADV was shown to completely release the fluorescein from the emulsions. ADV was also shown to release thrombin, dissolved in the W1 phase, which could be used in vivo to extend

  18. pH-Responsive Hydrogels with Dispersed Hydrophobic Nanoparticles for the Oral Delivery of Chemotherapeutics

    PubMed Central

    Schoener, Cody A.; Hutson, Heather N.; Peppas, Nicholas A.

    2012-01-01

    Amphiphilic polymer carriers were formed by polymerizing a hydrophilic, pH-responsive hydrogel composed of poly(methacrylic – grafted – ethylene glycol) (P(MAA-g-EG)) in the presence of hydrophobic PMMA nanoparticles. These polymer carriers were varied in PMMA nanoparticle content to elicit a variety of physiochemical properties which would preferentially load doxorubicin, a hydrophobic chemotherapeutic, and release doxorubicin locally in the colon for the treatment of colon cancers. Loading levels ranged from 49% to 64% and increased with increasing nanoparticle content. Doxorubicin loaded polymers were released in a physiological model where low pH was used to simulate the stomach and then stepped to more neutral conditions to simulate the upper small intestine. P(MAA-g-EG) containing nanoparticles were less mucoadhesive as determined using a tensile tester, polymer samples, and fresh porcine small intestine. The cytocompatibility of the polymer materials were assessed using cell lines representing the GI tract and colon cancer and were non-cytotoxic at varying concentrations and exposure times. PMID:23281185

  19. Nanoparticles for intracellular-targeted drug delivery

    NASA Astrophysics Data System (ADS)

    Paulo, Cristiana S. O.; Pires das Neves, Ricardo; Ferreira, Lino S.

    2011-12-01

    Nanoparticles (NPs) are very promising for the intracellular delivery of anticancer and immunomodulatory drugs, stem cell differentiation biomolecules and cell activity modulators. Although initial studies in the area of intracellular drug delivery have been performed in the delivery of DNA, there is an increasing interest in the use of other molecules to modulate cell activity. Herein, we review the latest advances in the intracellular-targeted delivery of short interference RNA, proteins and small molecules using NPs. In most cases, the drugs act at different cellular organelles and therefore the drug-containing NPs should be directed to precise locations within the cell. This will lead to the desired magnitude and duration of the drug effects. The spatial control in the intracellular delivery might open new avenues to modulate cell activity while avoiding side-effects.

  20. Recent advances in ocular drug delivery.

    PubMed

    Achouri, Djamila; Alhanout, Kamel; Piccerelle, Philippe; Andrieu, Véronique

    2013-11-01

    Amongst the various routes of drug delivery, the field of ocular drug delivery is one of the most interesting and challenging endeavors facing the pharmaceutical scientist. Recent research has focused on the characteristic advantages and limitations of the various drug delivery systems, and further research will be required before the ideal system can be developed. Administration of drugs to the ocular region with conventional delivery systems leads to short contact time of the formulations on the epithelium and fast elimination of drugs. This transient residence time involves poor bioavailability of drugs which can be explained by the tear production, non-productive absorption and impermeability of corneal epithelium. Anatomy of the eye is shortly presented and is connected with ophthalmic delivery and bioavailability of drugs. In the present update on ocular dosage forms, chemical delivery systems such as prodrugs, the use of cyclodextrins to increase solubility of various drugs, the concept of penetration enhancers and other ocular drug delivery systems such as polymeric gels, bioadhesive hydrogels, in-situ forming gels with temperature-, pH-, or osmotically induced gelation, combination of polymers and colloidal systems such as liposomes, niosomes, cubosomes, microemulsions, nanoemulsions and nanoparticles are discussed. Novel ophthalmic delivery systems propose the use of many excipients to increase the viscosity or the bioadhesion of the product. New formulations like gels or colloidal systems have been tested with numerous active substances by in vitro and in vivo studies. Sustained drug release and increase in drug bioavailability have been obtained, offering the promise of innovation in drug delivery systems for ocular administration. Combining different properties of pharmaceutical formulations appears to offer a genuine synergy in bioavailability and sustained release. Promising results are obtained with colloidal systems which present very comfortable

  1. State-of-the-Art Materials for Ultrasound-Triggered Drug Delivery

    PubMed Central

    Sirsi, Shashank; Borden, Mark

    2014-01-01

    Ultrasound is a unique and exciting theranostic modality that can be used to track drug carriers, trigger drug release and improve drug deposition with high spatial precision. In this review, we briefly describe the mechanisms of interaction between drug carriers and ultrasound waves, including cavitation, streaming and hyperthermia, and how those interactions can promote drug release and tissue uptake. We then discuss the rational design of some state-of-the-art materials for ultrasound-triggered drug delivery and review recent progress for each drug carrier, focusing on the delivery of chemotherapeutic agents such as doxorubicin. These materials include nanocarrier formulations, such as liposomes and micelles, designed specifically for ultrasound-triggered drug release, as well as microbubbles, microbubble-nanocarrier hybrids, microbubble-seeded hydrogels and phase-change agents. PMID:24389162

  2. Magnetic nanoparticles for gene and drug delivery

    PubMed Central

    McBain, Stuart C; Yiu, Humphrey HP; Dobson, Jon

    2008-01-01

    Investigations of magnetic micro- and nanoparticles for targeted drug delivery began over 30 years ago. Since that time, major progress has been made in particle design and synthesis techniques, however, very few clinical trials have taken place. Here we review advances in magnetic nanoparticle design, in vitro and animal experiments with magnetic nanoparticle-based drug and gene delivery, and clinical trials of drug targeting. PMID:18686777

  3. Smart Polymers in Nasal Drug Delivery

    PubMed Central

    Chonkar, Ankita; Nayak, Usha; Udupa, N.

    2015-01-01

    Nasal drug delivery has now been recognized as a promising route for drug delivery due to its capability of transporting a drug to systemic circulation and central nervous system. Though nasal mucosa offers improved bioavailability and quick onset of action of the drug, main disadvantage associated with nasal drug delivery is mucocilliary clearance due to which drug particles get cleared from the nose before complete absorption through nasal mucosa. Therefore, mucoadhesive polymeric approach can be successfully used to enhance the retention of the drug on nasal mucosal surface. Here, some of the aspects of the stimuli responsive polymers have been discussed which possess liquid state at the room temperature and in response to nasal temperature, pH and ions present in mucous, can undergo in situ gelation in nasal cavity. In this review, several temperature responsive, pH responsive and ion responsive polymers used in nasal delivery, their gelling mechanisms have been discussed. Smart polymers not only able to enhance the retention of the drug in nasal cavity but also provide controlled release, ease of administration, enhanced permeation of the drug and protection of the drug from mucosal enzymes. Thus smart polymeric approach can be effectively used for nasal delivery of peptide drugs, central nervous system dugs and hormones. PMID:26664051

  4. Nanoscale drug delivery for targeted chemotherapy.

    PubMed

    Xin, Yong; Huang, Qian; Tang, Jian-Qin; Hou, Xiao-Yang; Zhang, Pei; Zhang, Long Zhen; Jiang, Guan

    2016-08-28

    Despite significant improvements in diagnostic methods and innovations in therapies for specific cancers, effective treatments for neoplastic diseases still represent major challenges. Nanotechnology as an emerging technology has been widely used in many fields and also provides a new opportunity for the targeted delivery of cancer drugs. Nanoscale delivery of chemotherapy drugs to the tumor site is highly desirable. Recent studies have shown that nanoscale drug delivery systems not only have the ability to destroy cancer cells but may also be carriers for chemotherapy drugs. Some studies have demonstrated that delivery of chemotherapy via nanoscale carriers has greater therapeutic benefit than either treatment modality alone. In this review, novel approaches to nanoscale delivery of chemotherapy are described and recent progress in this field is discussed. PMID:27235607

  5. Co-administration of epithelial junction opener JO-1 improves the efficacy and safety of chemotherapeutic drugs

    PubMed Central

    Beyer, Ines; Cao, Hua; Persson, Jonas; Song, Hui; Richter, Maximilian; Feng, Qinghua; Yumul, Roma; van Rensburg, Ruan; Li, Zongyi; Berenson, Ronald; Carter, Darrick; Roffler, Steve; Drescher, Charles; Lieber, André

    2013-01-01

    Purpose Epithelial junctions between tumor cells inhibit the penetration of anti-cancer drugs into tumors. We previously reported on recombinant adenovirus serotype 3 derived protein (JO-1), which triggers transient opening of intercellular junctions in epithelial tumors through binding to desmoglein 2 (DSG2), and enhances the anti-tumor effects of several therapeutic monoclonal antibodies. The goal of this study was to evaluate whether JO-1 co-therapy can also improve the efficacy of chemotherapeutic drugs. Experimental Design The effect of intravenous application of JO-1 in combination with several chemotherapy drugs including paclitaxel/Taxol™, nanoparticle albumin bound paclitaxel/Abraxane™, liposomal doxorubicin/Doxil™ and irinotecan/Camptosar™, was tested in xenograft models for breast, colon, ovarian, gastric and lung cancer. Because JO-1 does not bind to mouse cells, for safety studies with JO-1, we also used human DSG2 (hDSG2) transgenic mice with tumors that overexpressed human DSG2. Results JO-1 increased the efficacy of chemotherapeutic drugs, and in several models overcame drug resistance. JO-1 treatment also allowed for the reduction of drug doses required to achieve anti-tumor effects. Importantly, JO-1 co-admininstration protected normal tissues, including bone marrow and intestinal epithelium, against toxic effects that are normally associated with chemotherapeutic agents. Using the hDSG2 transgenic mouse model, we demonstrated that JO-1 predominantly accumulates in tumors. Except for a mild, transient diarrhea, intravenous injection of JO-1 (2mg/kg) had no critical side effects on other tissues or hematological parameters in hDSG2-transgenic mice. Conclusions Our preliminary data suggest that JO-1 co-therapy has the potential to improve the therapeutic outcome of cancer chemotherapy. PMID:22535153

  6. Recent Advances in Delivery of Drug-Nucleic Acid Combinations for Cancer Treatment

    PubMed Central

    Li, Jing; Wang, Yan; Zhu, Yu; Oupický, David

    2013-01-01

    Cancer treatment that uses a combination of approaches with the ability to affect multiple disease pathways has been proven highly effective in the treatment of many cancers. Combination therapy can include multiple chemotherapeutics or combinations of chemotherapeutics with other treatment modalities like surgery or radiation. However, despite the widespread clinical use of combination therapies, relatively little attention has been given to the potential of modern nanocarrier delivery methods, like liposomes, micelles, and nanoparticles, to enhance the efficacy of combination treatments. This lack of knowledge is particularly notable in the limited success of vectors for the delivery of combinations of nucleic acids with traditional small molecule drugs. The delivery of drug-nucleic acid combinations is particularly challenging due to differences in the physicochemical properties of the two types of agents. This review discusses recent advances in the development of delivery methods using combinations of small molecule drugs and nucleic acid therapeutics to treat cancer. This review primarily focuses on the rationale used for selecting appropriate drug-nucleic acid combinations as well as progress in the development of nanocarriers suitable for simultaneous delivery of drug-nucleic acid combinations. PMID:23624358

  7. Hypoxia Responsive, Tumor Penetrating Lipid Nanoparticles for Delivery of Chemotherapeutics to Pancreatic Cancer Cell Spheroids.

    PubMed

    Kulkarni, Prajakta; Haldar, Manas K; Katti, Preeya; Dawes, Courtney; You, Seungyong; Choi, Yongki; Mallik, Sanku

    2016-08-17

    Solid tumors are often poorly irrigated due to structurally compromised microcirculation. Uncontrolled multiplication of cancer cells, insufficient blood flow, and the lack of enough oxygen and nutrients lead to the development of hypoxic regions in the tumor tissues. As the partial pressure of oxygen drops below the necessary level (10 psi), the cancer cells modulate their genetic makeup to survive. Hypoxia triggers tumor progression by enhancing angiogenesis, cancer stem cell production, remodeling of the extracellular matrix, and epigenetic changes in the cancer cells. However, the hypoxic regions are usually located deep in the tumors and are usually inaccessible to the intravenously injected drug carrier or the drug. Considering the designs of the reported nanoparticles, it is likely that the drug is delivered to the peripheral tumor tissues, close to the blood vessels. In this study, we prepared lipid nanoparticles (LNs) comprising the synthesized hypoxia-responsive lipid and a peptide-lipid conjugate. We observed that the resultant LNs penetrated to the hypoxic regions of the tumors. Under low oxygen partial pressure, the hypoxia-responsive lipid undergoes reduction, destabilizing the lipid membrane, and releasing encapsulated drugs from the nanoparticles. We demonstrated the results employing spheroidal cultures of the pancreatic cancer cells BxPC-3. We observed that the peptide-decorated, drug encapsulated LNs reduced the viability of pancreatic cancer cells of the spheroids to 35% under hypoxic conditions. PMID:27391789

  8. Anti-platelet agents augment cisplatin nanoparticle cytotoxicity by enhancing tumor vasculature permeability and drug delivery

    NASA Astrophysics Data System (ADS)

    Pandey, Ambarish; Sarangi, Sasmit; Chien, Kelly; Sengupta, Poulomi; Papa, Anne-Laure; Basu, Sudipta; Sengupta, Shiladitya

    2014-11-01

    Tumor vasculature is critically dependent on platelet mediated hemostasis and disruption of the same can augment delivery of nano-formulation based chemotherapeutic agents which depend on enhanced permeability and retention for tumor penetration. Here, we evaluated the role of Clopidogrel, a well-known inhibitor of platelet aggregation, in potentiating the tumor cytotoxicity of cisplatin nano-formulation in a murine breast cancer model. In vivo studies in murine syngeneic 4T1 breast cancer model showed a significant greater penetration of macromolecular fluorescent nanoparticles after clopidogrel pretreatment. Compared to self-assembling cisplatin nanoparticles (SACNs), combination therapy with clopidogrel and SACN was associated with a 4 fold greater delivery of cisplatin to tumor tissue and a greater reduction in tumor growth as well as higher survival rate. Clopidogrel enhances therapeutic efficiency of novel cisplatin based nano-formulations agents by increasing tumor drug delivery and can be used as a potential targeting agent for novel nano-formulation based chemotherapeutics.

  9. Inorganic Nanomaterials as Carriers for Drug Delivery.

    PubMed

    Chen, Shizhu; Hao, Xiaohong; Liang, Xingjie; Zhang, Qun; Zhang, Cuimiao; Zhou, Guoqiang; Shen, Shigang; Jia, Guang; Zhang, Jinchao

    2016-01-01

    For safe and effective therapy, drugs must be delivered efficiently and with minimal systemic side effects. Nanostructured drug carriers enable the delivery of small-molecule drugs as well as nucleic acids and proteins. Inorganic nanomaterials are ideal for drug delivery platforms due to their unique physicochemical properties, such as facile preparation, good storage stability and biocompatibility. Many inorganic nanostructure-based drug delivery platforms have been prepared. Although there are still many obstacles to overcome, significant advances have been made in recent years. This review focuses on the status and development of inorganic nanostructures, including silica, quantum dots, gold, carbon-based and magnetic iron oxide-based nanostructures, as carriers for chemical and biological drugs. We specifically highlight the extensive use of these inorganic drug carriers for cancer therapy. Finally, we discuss the most important areas in the field that urgently require further study. PMID:27301169

  10. Radiation sterilization of new drug delivery systems

    PubMed Central

    Abuhanoğlu, Gürhan

    2014-01-01

    Radiation sterilization has now become a commonly used method for sterilization of several active ingredients in drugs or drug delivery systems containing these substances. In this context, many applications have been performed on the human products that are required to be sterile, as well as on pharmaceutical products prepared to be developed. The new drug delivery systems designed to deliver the medication to the target tissue or organ, such as microspheres, nanospheres, microemulsion, and liposomal systems, have been sterilized by gamma (γ) and beta (β) rays, and more recently, by e-beam sterilization. In this review, the sterilization of new drug delivery systems was discussed other than conventional drug delivery systems by γ irradiation. PMID:24936306

  11. Modeling of diffusion controlled drug delivery.

    PubMed

    Siepmann, Juergen; Siepmann, Florence

    2012-07-20

    Mathematical modeling of drug release can be very helpful to speed up product development and to better understand the mechanisms controlling drug release from advanced delivery systems. Ideally, in silico simulations can quantitatively predict the impact of formulation and processing parameters on the resulting drug release kinetics. The aim of this article is to give an overview on the current state of the art of modeling drug release from delivery systems, which are predominantly controlled by diffusional mass transport. The inner structure of the device, the ratio "initial drug concentration:drug solubility" as well as the device geometry determine which type of mathematical equation must be applied. A straightforward "road map" is given, explaining how to identify the appropriate equation for a particular type of drug delivery system. The respective equations for a broad range of devices are indicated, including reservoir and matrix systems, exhibiting or not an initial excess of drug and the geometry of slabs, spheres and cylinders. The assumptions the models are based on as well as their limitations are pointed out. Practical examples illustrate the usefulness of mathematical modeling of diffusion controlled drug delivery. Due to the advances in information technology the importance of in silico optimization of advanced drug delivery systems can be expected to significantly increase in the future. PMID:22019555

  12. Potential of magnetic nanoparticles for targeted drug delivery

    PubMed Central

    Yang, Hung-Wei; Hua, Mu-Yi; Liu, Hao-Li; Huang, Chiung-Yin; Wei, Kuo-Chen

    2012-01-01

    Nanoparticles (NPs) play an important role in the molecular diagnosis, treatment, and monitoring of therapeutic outcomes in various diseases. Their nanoscale size, large surface area, unique capabilities, and negligible side effects make NPs highly effective for biomedical applications such as cancer therapy, thrombolysis, and molecular imaging. In particular, nontoxic superparamagnetic magnetic NPs (MNPs) with functionalized surface coatings can conjugate chemotherapeutic drugs or be used to target ligands/proteins, making them useful for drug delivery, targeted therapy, magnetic resonance imaging, transfection, and cell/protein/DNA separation. To optimize the therapeutic efficacy of MNPs for a specific application, three issues must be addressed. First, the efficacy of magnetic targeting/guidance is dependent on particle magnetization, which can be controlled by adjusting the reaction conditions during synthesis. Second, the tendency of MNPs to aggregate limits their therapeutic use in vivo; surface modifications to produce high positive or negative charges can reduce this tendency. Finally, the surface of MNPs can be coated with drugs which can be rapidly released after injection, resulting in targeting of low doses of the drug. Drugs therefore need to be conjugated to MNPs such that their release is delayed and their thermal stability enhanced. This chapter describes the creation of nanocarriers with a high drug-loading capacity comprised of a high-magnetization MNP core and a shell of aqueous, stable, conducting polyaniline derivatives and their applications in cancer therapy. It further summarizes some newly developed methods to synthesize and modify the surfaces of MNPs and their biomedical applications. PMID:24198498

  13. Perspectives on transdermal ultrasound mediated drug delivery

    PubMed Central

    Smith, Nadine Barrie

    2007-01-01

    The use of needles for multiple injection of drugs, such as insulin for diabetes, can be painful. As a result, prescribed drug noncompliance can result in severe medical complications. Several noninvasive methods exist for transdermal drug delivery. These include chemical mediation using liposomes and chemical enhancers or physical mechanisms such as microneedles, iontophoresis, electroporation, and ultrasound. Ultrasound enhanced transdermal drug delivery offers advantages over traditional drug delivery methods which are often invasive and painful. A broad review of the transdermal ultrasound drug delivery literature has shown that this technology offers promising potential for noninvasive drug administration. From a clinical perspective, few drugs, proteins or peptides have been successfully administered transdermally because of the low skin permeability to these relatively large molecules, although much work is underway to resolve this problem. The proposed mechanism of ultrasound has been suggested to be the result of cavitation, which is discussed along with the bioeffects from therapeutic ultrasound. For low frequencies, potential transducers which can be used for drug delivery are discussed, along with cautions regarding ultrasound safety versus efficacy. PMID:18203426

  14. The Benefits and Challenges Associated with the Use of Drug Delivery Systems in Cancer Therapy

    PubMed Central

    Cukierman, Edna; Khan, David R.

    2010-01-01

    The use of Drug Delivery Systems as nanocarriers for chemotherapeutic agents can improve the pharmacological properties of drugs by altering drug pharmacokinetics and biodistribution. Among the many drug delivery systems available, both micelles and liposomes have gained the most attention in recent years due to their clinical success. There are several formulations of these nanocarrier systems in various stages of clinical trials, as well as currently clinically approved liposomal-based drugs. In this review, we discuss these drug carrier systems, as well as current efforts that are being made in order to further improve their delivery efficacy through the incorporation of targeting ligands. In addition, this review discusses aspects of drug resistance attributed to the remodeling of the extracellular matrix that occurs during tumor development and progression, as well as to the acidic, hypoxic, and glucose deprived tumor microenvironment. Finally, we address future prospective approaches to overcoming drug resistance by further modifications made to these drug delivery systems, as well as the possibility of coencapsulation/coadministration of various drugs aimed to surmount some of these microenvironmental-influenced obstacles for efficacious drug delivery in chemotherapy. PMID:20417189

  15. Recent advances in ophthalmic drug delivery

    PubMed Central

    Kompella, Uday B; Kadam, Rajendra S; Lee, Vincent HL

    2011-01-01

    Topical ocular drug bioavailability is notoriously poor, in the order of 5% or less. This is a consequence of effective multiple barriers to drug entry, comprising nasolacrimal drainage, epithelial drug transport barriers and clearance from the vasculature in the conjunctiva. While sustained drug delivery to the back of the eye is now feasible with intravitreal implants such as Vitrasert™ (~6 months), Retisert™ (~3 years) and Iluvien™ (~3 years), currently there are no marketed delivery systems for long-term drug delivery to the anterior segment of the eye. The purpose of this article is to summarize the resurgence in interest to prolong and improve drug entry from topical administration. These approaches include mucoadhesives, viscous polymer vehicles, transporter-targeted prodrug design, receptor-targeted functionalized nanoparticles, iontophoresis, punctal plug and contact lens delivery systems. A few of these delivery systems might be useful in treating diseases affecting the back of the eye. Their effectiveness will be compared against intravitreal implants (upper bound of effectiveness) and trans-scleral systems (lower bound of effectiveness). Refining the animal model by incorporating the latest advances in microdialysis and imaging technology is key to expanding the knowledge central to the design, testing and evaluation of the next generation of innovative ocular drug delivery systems. PMID:21399724

  16. Synthetic micro/nanomotors in drug delivery.

    PubMed

    Gao, Wei; Wang, Joseph

    2014-09-21

    Nanomachines offer considerable promise for the treatment of diseases. The ability of man-made nanomotors to rapidly deliver therapeutic payloads to their target destination represents a novel nanomedicine approach. Synthetic nanomotors, based on a multitude of propulsion mechanisms, have been developed over the past decade toward diverse biomedical applications. In this review article, we journey from the use of chemically powered drug-delivery nanovehicles to externally actuated (fuel-free) drug-delivery nanomachine platforms, and conclude with future prospects and challenges for such practical propelling drug-delivery systems. As future micro/nanomachines become more powerful and functional, these tiny devices are expected to perform more demanding biomedical tasks and benefit different drug delivery applications. PMID:25096021

  17. Chitosan Microspheres in Novel Drug Delivery Systems

    PubMed Central

    Mitra, Analava; Dey, Baishakhi

    2011-01-01

    The main aim in the drug therapy of any disease is to attain the desired therapeutic concentration of the drug in plasma or at the site of action and maintain it for the entire duration of treatment. A drug on being used in conventional dosage forms leads to unavoidable fluctuations in the drug concentration leading to under medication or overmedication and increased frequency of dose administration as well as poor patient compliance. To minimize drug degradation and loss, to prevent harmful side effects and to increase drug bioavailability various drug delivery and drug targeting systems are currently under development. Handling the treatment of severe disease conditions has necessitated the development of innovative ideas to modify drug delivery techniques. Drug targeting means delivery of the drug-loaded system to the site of interest. Drug carrier systems include polymers, micelles, microcapsules, liposomes and lipoproteins to name some. Different polymer carriers exert different effects on drug delivery. Synthetic polymers are usually non-biocompatible, non-biodegradable and expensive. Natural polymers such as chitin and chitosan are devoid of such problems. Chitosan comes from the deacetylation of chitin, a natural biopolymer originating from crustacean shells. Chitosan is a biocompatible, biodegradable, and nontoxic natural polymer with excellent film-forming ability. Being of cationic character, chitosan is able to react with polyanions giving rise to polyelectrolyte complexes. Hence chitosan has become a promising natural polymer for the preparation of microspheres/nanospheres and microcapsules. The techniques employed to microencapsulate with chitosan include ionotropic gelation, spray drying, emulsion phase separation, simple and complex coacervation. This review focuses on the preparation, characterization of chitosan microspheres and their role in novel drug delivery systems. PMID:22707817

  18. Drug Delivery Systems: Entering the Mainstream

    NASA Astrophysics Data System (ADS)

    Allen, Theresa M.; Cullis, Pieter R.

    2004-03-01

    Drug delivery systems (DDS) such as lipid- or polymer-based nanoparticles can be designed to improve the pharmacological and therapeutic properties of drugs administered parenterally. Many of the early problems that hindered the clinical applications of particulate DDS have been overcome, with several DDS formulations of anticancer and antifungal drugs now approved for clinical use. Furthermore, there is considerable interest in exploiting the advantages of DDS for in vivo delivery of new drugs derived from proteomics or genomics research and for their use in ligand-targeted therapeutics.

  19. Vesicular carriers for dermal drug delivery.

    PubMed

    Sinico, Chiara; Fadda, Anna Maria

    2009-08-01

    The skin can offer several advantages as a route of drug administration although its barrier nature makes it difficult for most drugs to penetrate into and permeate through it. During the past decades there has been a lot of interest in lipid vesicles as a tool to improve drug topical delivery. Vesicular systems such as liposomes, niosomes, ethosomes and elastic, deformable vesicles provide an alternative for improved skin drug delivery. The function of vesicles as topical delivery systems is controversial with variable effects being reported in relation to the type of vesicles and their composition. In fact, vesicles can act as drug carriers controlling active release; they can provide a localized depot in the skin for dermally active compounds and enhance transdermal drug delivery. A wide variety of lipids and surfactants can be used to prepare vesicles, which are commonly composed of phospholipids (liposomes) or non-ionic surfactants (niosomes). Vesicle composition and preparation method influence their physicochemical properties (size, charge, lamellarity, thermodynamic state, deformability) and therefore their efficacy as drug delivery systems. A review of vesicle value in localizing drugs within the skin at the site of action will be provided with emphasis on their potential mechanism of action. PMID:19569979

  20. Methods of Drug Delivery in Neurotrauma.

    PubMed

    Deng-Bryant, Ying; Readnower, Ryan; Leung, Lai Yee; Tortella, Frank; Shear, Deborah

    2016-01-01

    The central nervous system (CNS) is protected by blood-brain barrier (BBB) and blood-cerebrospinal-fluid (CSF) barrier that limit toxic agents and most molecules from penetrating the brain and spinal cord. However, these barriers also prevent most pharmaceuticals from entering into the CNS. Drug delivery to the CNS following neurotrauma is complicated. Although studies have shown BBB permeability increases in various TBI models, it remains as the key mitigating factor for delivering drugs into the CNS. The commonly used methods for drug delivery in preclinical neurotrauma studies include intraperitoneal, subcutaneous, intravenous, and intracerebroventricular delivery. It should be noted that for a drug to be successfully translated into the clinic, it needs to be administered preclinically as it would be anticipated to be administered to patients. And this likely leads to better dose selection of the drug, as well as recognition of any possible side effects, prior to transition into a clinical trial. Additionally, novel approach that is noninvasive and yet circumvents BBB, such as drug delivery through nerve pathways innervating the nasal passages, needs to be investigated in animal models, as it may provide a viable drug delivery method for patients who sustain mild CNS injury or require chronic treatments. Therefore, the focus of this chapter is to present rationales and methods for delivering drugs by IV infusion via the jugular vein, and intranasally in preclinical studies. PMID:27604714

  1. [Progression of drug delivery system for glaucoma].

    PubMed

    Xu, Yan; Lyu, Liu

    2014-12-01

    Reduction of intraocular pressure (IOP) by drugs is a major treatment for glaucoma. Clinically, diverse antiglaucoma drugs take effect to decrease the IOP through different mechanisms.However, due to limitations of traditional form of eye drops, the bioavailability of the drug and the patient compliance is lowered, the clinical efficacy is not good and also some toxic and side-effects come out.Otherwise, traditional medication is not suitable for neuroprotective drugs to work on both retina and optic nerve. Drug delivery system has the potential to improve the bioavailability of the drug, prolong the time of drug action, decrease the dosage and frequency of drugs, reduce the side-effects, and improve the patient compliance and efficacy.It is one of the most important studies in glaucoma medication development because it is valuable for patients' neuroprotection.Nowadays, several novel delivery systems have been designed. This review will focus on the progressions of some of the sustained-release antiglaucoma eye drops, polymeric gels, colloidal systems, membrane-controlled drug delivery system, ocular implants, and transscleral drug delivery systems. PMID:25619186

  2. Role of microemuslsions in advanced drug delivery.

    PubMed

    Sharma, Aman Kumar; Garg, Tarun; Goyal, Amit K; Rath, Goutam

    2016-06-01

    Microemulsions have gained significant attention from formulation scientists since the time they have been discovered, because of their excellent properties related to their stability, solubility, simplicity, and formulation aspects. The application of microemulsions is not limited to drug delivery via the oral, topical or ocular routes, but may also be seen in cosmetics, immunology, sensor devices, coating, textiles, analytical chemistry, and spermicide. Finally, the objective of this review is to discuss briefly the applications of microemulsions in advanced drug delivery. PMID:25711493

  3. Osmotically controlled drug delivery system with associated drugs.

    PubMed

    Gupta, Brahma Prakash; Thakur, Navneet; Jain, Nishi P; Banweer, Jitendra; Jain, Surendra

    2010-01-01

    Conventional drug delivery systems have slight control over their drug release and almost no control over the effective concentration at the target site. This kind of dosing pattern may result in constantly changing, unpredictable plasma concentrations. Drugs can be delivered in a controlled pattern over a long period of time by the controlled or modified release drug delivery systems. They include dosage forms for oral and transdermal administration as well as injectable and implantable systems. For most of drugs, oral route remains as the most acceptable route of administration. Certain molecules may have low oral bioavailability because of solubility or permeability limitations. Development of an extended release dosage form also requires reasonable absorption throughout the gastro-intestinal tract (GIT). Among the available techniques to improve the bioavailability of these drugs fabrication of osmotic drug delivery system is the most appropriate one. Osmotic drug delivery systems release the drug with the zero order kinetics which does not depend on the initial concentration and the physiological factors of GIT. This review brings out new technologies, fabrication and recent clinical research in osmotic drug delivery. PMID:21486532

  4. The application of prodrug-based nano-drug delivery strategy in cancer combination therapy.

    PubMed

    Ge, Yanxiu; Ma, Yakun; Li, Lingbing

    2016-10-01

    Single drug therapy that leads to the multidrug resistance of cancer cells and severe side-effect is a thing of the past. Combination therapies that affect multiple signaling pathways have been the focus of recent active research. Due to the successful development of prodrug-based nano-drug delivery systems (P-N-DDSs), their use has been extended to combination therapy as drug delivery platforms. In this review, we focus specifically on the P-N-DDSs in the field of combination therapy including the combinations of prodrugs with different chemotherapeutic agents, other therapeutic agents, nucleic acid or the combination of different types of therapy (e.g. chemotherapy and phototherapy). The relevant examples of prodrug-based nanoparticulate drug delivery strategy in combination cancer therapy from the recent literature are discussed to demonstrate the feasibilities of relevant technology. PMID:27400243

  5. Double layered hydroxides as potential anti-cancer drug delivery agents.

    PubMed

    Riaz, Ufana; Ashraf, S M

    2013-04-01

    The emergence of nanotechnology has changed the scenario of the medical world by revolutionizing the diagnosis, monitoring and treatment of cancer. This nanotechnology has been proved miraculous in detecting cancer cells, delivering chemotherapeutic agents and monitoring treatment from non-specific to highly targeted killing of tumor cells. In the past few decades, a number of inorganic materials have been investigated such as calcium phosphate, gold, carbon materials, silicon oxide, iron oxide, and layered double hydroxide (LDH) for examining their efficacy in targeting drug delivery. The reason behind the selection of these inorganic materials was their versatile and unique features efficient in drug delivery, such as wide availability, rich surface functionality, good biocompatibility, potential for target delivery, and controlled release of the drug from these inorganic nanomaterials. Although, the drug-LDH hybrids are found to be quite instrumental because of their application as advanced anti-cancer drug delivery systems, there has not been much research on them. This mini review is set to highlight the advancement made in the use of layered double hydroxides (LDHs) as anti-cancer drug delivery agents. Along with the advantages of LDHs as anti-cancer drug delivery agents, the process of interaction of some of the common anti-cancer drugs with LDH has also been discussed. PMID:23170959

  6. Microneedles for drug and vaccine delivery

    PubMed Central

    Kim, Yeu-Chun; Park, Jung-Hwan; Prausnitz, Mark R.

    2012-01-01

    Microneedles were first conceptualized for drug delivery many decades ago, but only became the subject of significant research starting in the mid-1990’s when microfabrication technology enabled their manufacture as (i) solid microneedles for skin pretreatment to increase skin permeability, (ii) microneedles coated with drug that dissolves off in the skin, (iii) polymer microneedles that encapsulate drug and fully dissolve in the skin and (iv) hollow microneedles for drug infusion into the skin. As shown in more than 350 papers now published in the field, microneedles have been used to deliver a broad range of different low molecular weight drugs, biotherapeutics and vaccines, including published human studies with a number of small-molecule and protein drugs and vaccines. Influenza vaccination using a hollow microneedle is in widespread clinical use and a number of solid microneedle products are sold for cosmetic purposes. In addition to applications in the skin, microneedles have also been adapted for delivery of bioactives into the eye and into cells. Successful application of microneedles depends on device function that facilitates microneedle insertion and possible infusion into skin, skin recovery after microneedle removal, and drug stability during manufacturing, storage and delivery, and on patient outcomes, including lack of pain, skin irritation and skin infection, in addition to drug efficacy and safety. Building off a strong technology base and multiple demonstrations of successful drug delivery, microneedles are poised to advance further into clinical practice to enable better pharmaceutical therapies, vaccination and other applications. PMID:22575858

  7. Progress in antiretroviral drug delivery using nanotechnology

    PubMed Central

    Mallipeddi, Rama; Rohan, Lisa Cencia

    2010-01-01

    There are currently a number of antiretroviral drugs that have been approved by the Food and Drug Administration for use in the treatment of human immunodeficiency virus (HIV). More recently, antiretrovirals are being evaluated in the clinic for prevention of HIV infection. Due to the challenging nature of treatment and prevention of this disease, the use of nanocarriers to achieve more efficient delivery of antiretroviral drugs has been studied. Various forms of nanocarriers, such as nanoparticles (polymeric, inorganic, and solid lipid), liposomes, polymeric micelles, dendrimers, cyclodextrins, and cell-based nanoformulations have been studied for delivery of drugs intended for HIV prevention or therapy. The aim of this review is to provide a summary of the application of nanocarrier systems to the delivery of anti-HIV drugs, specifically antiretrovirals. For anti-HIV drugs to be effective, adequate distribution to specific sites in the body must be achieved, and effective drug concentrations must be maintained at those sites for the required period of time. Nanocarriers provide a means to overcome cellular and anatomical barriers to drug delivery. Their application in the area of HIV prevention and therapy may lead to the development of more effective drug products for combating this pandemic disease. PMID:20957115

  8. Calcium phosphate ceramics in drug delivery

    NASA Astrophysics Data System (ADS)

    Bose, Susmita; Tarafder, Solaiman; Edgington, Joe; Bandyopadhyay, Amit

    2011-04-01

    Calcium phosphate (CaP) particulates, cements and scaffolds have attracted significant interest as drug delivery vehicles. CaP systems, including both hydroxyapaptite and tricalcium phosphates, possess variable stoichiometry, functionality and dissolution properties which make them suitable for cellular delivery. Their chemical similarity to bone and thus biocompatibility, as well as variable surface charge density contribute to their controlled release properties. Among specific research areas, nanoparticle size, morphology, surface area due to porosity, and chemistry controlled release kinetics are the most active. This article discusses CaP systems in their particulate, cements, and scaffold forms for drug, protein, and growth factor delivery toward orthopedic and dental applications.

  9. Transpapillary Drug Delivery to the Breast

    PubMed Central

    Dave, Kaushalkumar; Averineni, Ranjith; Sahdev, Preety; Perumal, Omathanu

    2014-01-01

    The study was aimed at investigating localized topical drug delivery to the breast via mammary papilla (nipple). 5-fluorouracil (5-FU) and estradiol (EST) were used as model hydrophilic and hydrophobic compounds respectively. Porcine and human nipple were used for in-vitro penetration studies. The removal of keratin plug enhanced the drug transport through the nipple. The drug penetration was significantly higher through the nipple compared to breast skin. The drug’s lipophilicity had a significant influence on drug penetration through nipple. The ducts in the nipple served as a major transport pathway to the underlying breast tissue. Results showed that porcine nipple could be a potential model for human nipple. The topical application of 5-FU on the rat nipple resulted in high drug concentration in the breast and minimal drug levels in plasma and other organs. Overall, the findings from this study demonstrate the feasibility of localized drug delivery to the breast through nipple. PMID:25545150

  10. BMX Negatively Regulates BAK Function, Thereby Increasing Apoptotic Resistance to Chemotherapeutic Drugs.

    PubMed

    Fox, Joanna L; Storey, Alan

    2015-04-01

    The ability of chemotherapeutic agents to induce apoptosis, predominantly via the mitochondrial (intrinsic) apoptotic pathway, is thought to be a major determinant of the sensitivity of a given cancer to treatment. Intrinsic apoptosis, regulated by the BCL2 family, integrates diverse apoptotic signals to determine cell death commitment and then activates the nodal effector protein BAK to initiate the apoptotic cascade. In this study, we identified the tyrosine kinase BMX as a direct negative regulator of BAK function. BMX associates with BAK in viable cells and is the first kinase to phosphorylate the key tyrosine residue needed to maintain BAK in an inactive conformation. Importantly, elevated BMX expression prevents BAK activation in tumor cells treated with chemotherapeutic agents and is associated with increased resistance to apoptosis and decreased patient survival. Accordingly, BMX expression was elevated in prostate, breast, and colon cancers compared with normal tissue, including in aggressive triple-negative breast cancers where BMX overexpression may be a novel biomarker. Furthermore, BMX silencing potentiated BAK activation, rendering tumor cells hypersensitive to otherwise sublethal doses of clinically relevant chemotherapeutic agents. Our finding that BMX directly inhibits a core component of the intrinsic apoptosis machinery opens opportunities to improve the efficacy of existing chemotherapy by potentiating BAK-driven cell death in cancer cells. PMID:25649765

  11. Chemotherapeutic Drugs Induce ATP Release via Caspase-gated Pannexin-1 Channels and a Caspase/Pannexin-1-independent Mechanism*

    PubMed Central

    Boyd-Tressler, Andrea; Penuela, Silvia; Laird, Dale W.; Dubyak, George R.

    2014-01-01

    Anti-tumor immune responses have been linked to the regulated release of ATP from apoptotic cancer cells to engage P2 purinergic receptor signaling cascades in nearby leukocytes. We used the Jurkat T cell acute lymphocytic leukemia model to characterize the role of pannexin-1 (Panx1) channels in the release of nucleotides during chemotherapeutic drug-induced apoptosis. Diverse pro-apoptotic drugs, including topoisomerase II inhibitors, kinase inhibitors, and proteosome inhibitors, induced functional activation of Panx1 channels via caspase-3-mediated cleavage of the Panx1 autoinhibitory C-terminal domain. The caspase-activated Panx1 channels mediated efflux of ATP, but also ADP and AMP, with the latter two comprising >90% of the released adenine nucleotide pool as cells transitioned from the early to late stages of apoptosis. Chemotherapeutic drugs also activated an alternative caspase- and Panx1-independent pathway for ATP release from Jurkat cells in the presence of benzyloxycarbonyl-VAD, a pan-caspase inhibitor. Comparison of Panx1 levels indicated much higher expression in leukemic T lymphocytes than in normal, untransformed T lymphoblasts. This suggests that signaling roles for Panx1 may be amplified in leukemic leukocytes. Together, these results identify chemotherapy-activated pannexin-1 channels and ATP release as possible mediators of paracrine interaction between dying tumor cells and the effector leukocytes that mediate immunogenic anti-tumor responses. PMID:25112874

  12. Novel drug delivery systems for glaucoma

    PubMed Central

    Lavik, E; Kuehn, M H; Kwon, Y H

    2011-01-01

    Reduction of intraocular pressure (IOP) by pharmaceutical or surgical means has long been the standard treatment for glaucoma. A number of excellent drugs are available that are effective in reducing IOP. These drugs are typically applied as eye drops. However, patient adherence can be poor, thus reducing the clinical efficacy of the drugs. Several novel delivery systems designed to address the issue of adherence and to ensure consistent reduction of IOP are currently under development. These delivery systems include contact lenses-releasing glaucoma medications, injectables such as biodegradable micro- and nanoparticles, and surgically implanted systems. These new technologies are aimed at increasing clinical efficacy by offering multiple delivery options and are capable of managing IOP for several months. There is also a desire to have complementary neuroprotective approaches for those who continue to show progression, despite IOP reduction. Many potential neuroprotective agents are not suitable for traditional oral or drop formulations. Their potential is dependent on developing suitable delivery systems that can provide the drugs in a sustained, local manner to the retina and optic nerve. Drug delivery systems have the potential to improve patient adherence, reduce side effects, increase efficacy, and ultimately, preserve sight for glaucoma patients. In this review, we discuss benefits and limitations of the current systems of delivery and application, as well as those on the horizon. PMID:21475311

  13. Microfluidic device for drug delivery

    NASA Technical Reports Server (NTRS)

    Beebe, David J. (Inventor); MacDonald, Michael J. (Inventor); Eddington, David T. (Inventor); Mensing, Glennys A. (Inventor)

    2010-01-01

    A microfluidic device is provided for delivering a drug to an individual. The microfluidic device includes a body that defines a reservoir for receiving the drug therein. A valve interconnects the reservoir to an output needle that is insertable into the skin of an individual. A pressure source urges the drug from the reservoir toward the needle. The valve is movable between a closed position preventing the flow of the drug from the reservoir to the output needle and an open position allowing for the flow of the drug from the reservoir to the output needle in response to a predetermined condition in the physiological fluids of the individual.

  14. Learning from Biology: Synthetic Lipoproteins for Drug Delivery

    PubMed Central

    Huang, Huang; Cruz, William; Chen, Juan; Zheng, Gang

    2014-01-01

    Synthetic lipoproteins represent a relevant tool for targeted delivery of biological/chemical agents (chemotherapeutics, siRNAs, photosensitizers and imaging contrast agents) into various cell types. These nanoparticles offer a number of advantages on drugs delivery over their native counterparts while retaining their natural characteristics and biological functions. Their ultra-small size (<30nm), high biocompatibility, favorable circulation half-life and natural ability to bind specific lipoprotein receptors i.e. low-density lipoprotein receptor (LDLR) and Scavenger receptor class B member 1 (SRB1) that are found in a number of pathological conditions (e.g. cancer, atherosclerosis), make them superior delivery strategies when compared to other nanoparticle systems. We review the various approaches that have been developed for the generation of synthetic lipoproteins and their respective applications in vitro and in vivo. More specifically, we summarize the way to address the limitation on use of reconstituted lipoproteins by means of natural or recombinant apolipoproteins, as well as apolipoprotein mimetic molecules. Finally, we provide an overview of the advantages and disadvantages of these approaches and discuss future perspectives for clinical translation of these nanoparticles. PMID:25346461

  15. Implication of nanofibers in oral drug delivery.

    PubMed

    Kapahi, Himani; Khan, Nikhat Mansoor; Bhardwaj, Ankur; Mishra, Neeraj

    2015-01-01

    Nanofibers has gained significant prominence in recent years due to its wide applications in medicinal pharmacy, textile, tissue engineering and in various drug delivery system. In oral drug delivery system (DDS), nanofibers can be delivered as Nanofiber scaffolds, electrosponge nanofibers as oral fast delivery system, multilayered nanofiber loaded mashes, surface modified cross-linked electrospun nanofibers. Nanofibers are of 50- 1000 nm size fibres having large surface area, high porosity, small pore size, low density. Various approaches for formulation of nanofibers are molecular assembly, thermally induced phase separation, electrospining. Most commonly used by using electrospining polymer nanofibres with different range can be produced collective usage of electro spinning with pharmaceutical polymers offers novel tactics for developing drug delivery system (DDS). Different polymers used in preparation of nanofibers include biodegradable hydrophilic polymers, hydrophobic polymers and amphiphilic polymers. Electrospun nanofibers are often used to load insoluble drugs for enhancing their dissolution properties due to their high surface area per unit mass. Besides the water insoluble drugs freely water soluble sodium can also spun into the fibers. The most commonly polymers used for nanofibers are gelatin, dextran, nylon, polystyrene, polyacrylonitrile, polycarbonate, polyimides, poly vinyl alchol, polybenzimidazole. Delivery systems reviewed rely on temporal control, changes in pH along the GIT, the action of local enzymes to trigger drug release, and changes in intraluminal pressure. Dissolution of enteric polymer coatings due to a change in local pH and reduction of azo-bonds to release an active agent are both used in commercially marketed products. In vitro and in vivo studies have demonstrated that the release rates of drugs from these nanofiber formulations are enhanced compared to those from original drug substance. This review is focused on the different

  16. Electroresponsive nanoparticles for drug delivery on demand

    NASA Astrophysics Data System (ADS)

    Samanta, Devleena; Hosseini-Nassab, Niloufar; Zare, Richard N.

    2016-04-01

    The potential of electroresponsive conducting polymer nanoparticles to be used as general drug delivery systems that allow electrically pulsed, linearly scalable, and on demand release of incorporated drugs is demonstrated. As examples, facile release from polypyrrole nanoparticles is shown for fluorescein, a highly water-soluble model compound, piroxicam, a lipophilic small molecule drug, and insulin, a large hydrophilic peptide hormone. The drug loading is about 13 wt% and release is accomplished in a few seconds by applying a weak constant current or voltage. To identify the parameters that should be finely tuned to tailor the carrier system for the release of the therapeutic molecule of interest, a systematic study of the factors that affect drug delivery is performed, using fluorescein as a model compound. The parameters studied include current, time, voltage, pH, temperature, particle concentration, and ionic strength. Results indicate that there are several degrees of freedom that can be optimized for efficient drug delivery. The ability to modulate linearly drug release from conducting polymers with the applied stimulus can be utilized to design programmable and minimally invasive drug delivery devices.

  17. Lipid-Based Drug Delivery Systems

    PubMed Central

    Shrestha, Hina; Bala, Rajni; Arora, Sandeep

    2014-01-01

    The principle objective of formulation of lipid-based drugs is to enhance their bioavailability. The use of lipids in drug delivery is no more a new trend now but is still the promising concept. Lipid-based drug delivery systems (LBDDS) are one of the emerging technologies designed to address challenges like the solubility and bioavailability of poorly water-soluble drugs. Lipid-based formulations can be tailored to meet a wide range of product requirements dictated by disease indication, route of administration, cost consideration, product stability, toxicity, and efficacy. These formulations are also a commercially viable strategy to formulate pharmaceuticals, for topical, oral, pulmonary, or parenteral delivery. In addition, lipid-based formulations have been shown to reduce the toxicity of various drugs by changing the biodistribution of the drug away from sensitive organs. However, the number of applications for lipid-based formulations has expanded as the nature and type of active drugs under investigation have become more varied. This paper mainly focuses on novel lipid-based formulations, namely, emulsions, vesicular systems, and lipid particulate systems and their subcategories as well as on their prominent applications in pharmaceutical drug delivery. PMID:26556202

  18. Electroresponsive nanoparticles for drug delivery on demand.

    PubMed

    Samanta, Devleena; Hosseini-Nassab, Niloufar; Zare, Richard N

    2016-04-28

    The potential of electroresponsive conducting polymer nanoparticles to be used as general drug delivery systems that allow electrically pulsed, linearly scalable, and on demand release of incorporated drugs is demonstrated. As examples, facile release from polypyrrole nanoparticles is shown for fluorescein, a highly water-soluble model compound, piroxicam, a lipophilic small molecule drug, and insulin, a large hydrophilic peptide hormone. The drug loading is about 13 wt% and release is accomplished in a few seconds by applying a weak constant current or voltage. To identify the parameters that should be finely tuned to tailor the carrier system for the release of the therapeutic molecule of interest, a systematic study of the factors that affect drug delivery is performed, using fluorescein as a model compound. The parameters studied include current, time, voltage, pH, temperature, particle concentration, and ionic strength. Results indicate that there are several degrees of freedom that can be optimized for efficient drug delivery. The ability to modulate linearly drug release from conducting polymers with the applied stimulus can be utilized to design programmable and minimally invasive drug delivery devices. PMID:27088543

  19. Electronics will transform drug delivery devices.

    PubMed

    Mazzoni, Paolo

    2004-03-01

    The drug delivery device sector will be transformed by electronically controlled alternatives that will maximise user safety and medical effectiveness and open the way to the introduction of high-power, next-generation drugs. Current business partnerships will need to change to allow this to happen. PMID:15154333

  20. A pulsed mode electrolytic drug delivery device

    NASA Astrophysics Data System (ADS)

    Yi, Ying; Buttner, Ulrich; Carreno, Armando A. A.; Conchouso, David; Foulds, Ian G.

    2015-10-01

    This paper reports the design of a proof-of-concept drug delivery device that is actuated using the bubbles formed during electrolysis. The device uses a platinum (Pt) coated nickel (Ni) metal foam and a solid drug in reservoir (SDR) approach to improve the device’s performance. This electrochemically-driven pump has many features that are unlike conventional drug delivery devices: it is capable of pumping periodically and being refilled automatically; it features drug release control; and it enables targeted delivery. Pt-coated metal foam is used as a catalytic reforming element, which reduces the period of each delivery cycle. Two methods were used for fabricating the Pt-coated metal: sputtering and electroplating. Of these two methods, the sputtered Pt-coated metal foam has a higher pumping rate; it also has a comparable recombination rate when compared to the electroplated Pt-coated metal foam. The only drawback of this catalytic reformer is that it consumes nickel scaffold. Considering long-term applications, the electroplated Pt metal foam was selected for drug delivery, where a controlled drug release rate of 2.2 μg  ±  0.3 μg per actuation pulse was achieved using 4 mW of power.

  1. Microfabrication Technologies for Oral Drug Delivery

    PubMed Central

    Sant, Shilpa; Tao, Sarah L.; Fisher, Omar; Xu, Qiaobing; Peppas, Nicholas A.; Khademhosseini, Ali

    2012-01-01

    Micro-/nanoscale technologies such as lithographic techniques and microfluidics offer promising avenues to revolutionalize the fields of tissue engineering, drug discovery, diagnostics and personalized medicine. Microfabrication techniques are being explored for drug delivery applications due to their ability to combine several features such as precise shape and size into a single drug delivery vehicle. They also offer to create unique asymmetrical features incorporated into single or multiple reservoir systems maximizing contact area with the intestinal lining. Combined with intelligent materials, such microfabricated platforms can be designed to be bioadhesive and stimuli-responsive. Apart from drug delivery devices, microfabrication technologies offer exciting opportunities to create biomimetic gastrointestinal tract models incorporating physiological cell types, flow patterns and brush-border like structures. Here we review the recent developments in this field with a focus on the applications of microfabrication in the development of oral drug delivery devices and biomimetic gastrointestinal tract models that can be used to evaluate the drug delivery efficacy. PMID:22166590

  2. Liposome-like Nanostructures for Drug Delivery

    PubMed Central

    Gao, Weiwei; Hu, Che-Ming J.; Fang, Ronnie H.; Zhang, Liangfang

    2013-01-01

    Liposomes are a class of well-established drug carriers that have found numerous therapeutic applications. The success of liposomes, together with recent advancements in nanotechnology, has motivated the development of various novel liposome-like nanostructures with improved drug delivery performance. These nanostructures can be categorized into five major varieties, namely: (1) polymer-stabilized liposomes, (2) nanoparticle-stabilized liposomes, (3) core-shell lipid-polymer hybrid nanoparticles, (4) natural membrane-derived vesicles, and (5) natural membrane coated nanoparticles. They have received significant attention and have become popular drug delivery platforms. Herein, we discuss the unique strengths of these liposome-like platforms in drug delivery, with a particular emphasis on how liposome-inspired novel designs have led to improved therapeutic efficacy, and review recent progress made by each platform in advancing healthcare. PMID:24392221

  3. Brain drug delivery systems for neurodegenerative disorders.

    PubMed

    Garbayo, E; Ansorena, E; Blanco-Prieto, M J

    2012-09-01

    Neurodegenerative disorders (NDs) are rapidly increasing as population ages. However, successful treatments for NDs have so far been limited and drug delivery to the brain remains one of the major challenges to overcome. There has recently been growing interest in the development of drug delivery systems (DDS) for local or systemic brain administration. DDS are able to improve the pharmacological and therapeutic properties of conventional drugs and reduce their side effects. The present review provides a concise overview of the recent advances made in the field of brain drug delivery for treating neurodegenerative disorders. Examples include polymeric micro and nanoparticles, lipidic nanoparticles, pegylated liposomes, microemulsions and nanogels that have been tested in experimental models of Parkinson's, Alzheimer's and Huntington's disease. Overall, the results reviewed here show that DDS have great potential for NDs treatment. PMID:23016644

  4. Amorphous powders for inhalation drug delivery.

    PubMed

    Chen, Lan; Okuda, Tomoyuki; Lu, Xiang-Yun; Chan, Hak-Kim

    2016-05-01

    For inhalation drug delivery, amorphous powder formulations offer the benefits of increased bioavailability for poorly soluble drugs, improved biochemical stability for biologics, and expanded options of using various drugs and their combinations. However, amorphous formulations usually have poor physicochemical stability. This review focuses on inhalable amorphous powders, including the production methods, the active pharmaceutical ingredients and the excipients with a highlight on stabilization of the particles. PMID:26780404

  5. Drug Delivery Research: The Invention Cycle.

    PubMed

    Park, Kinam

    2016-07-01

    Controlled drug delivery systems have been successful in introducing improved formulations for better use of existing drugs and novel delivery of biologicals. The initial success of producing many oral products and some injectable depot formulations, however, reached a plateau, and the progress over the past three decades has been slow. This is likely due to the difficulties of formulating hydrophilic, high molecular weight drugs, such as proteins and nucleic acids, for targeting specific cells, month-long sustained delivery, and pulsatile release. Since the approaches that have served well for delivery of small molecules are not applicable to large molecules, it is time to develop new methods for biologicals. The process of developing future drug delivery systems, termed as the invention cycle, is proposed, and it starts with clearly defining the problems for developing certain formulations. Once the problems are well-defined, creative imagination examines all potential options and selects the best answer and alternatives. Then, innovation takes over to generate unique solutions for developing new formulations that resolve the previously identified problems. Ultimately, the new delivery systems will have to go through a translational process to produce the final formulations for clinical use. The invention cycle also emphasizes examining the reasons for success of certain formulations, not just the reasons for failure of many systems. Implementation of the new invention cycle requires new mechanisms of funding the younger generation of scientists and a new way of identifying their achievements, thereby releasing them from the burden of short-termism. PMID:26962897

  6. Inhaled nano- and microparticles for drug delivery

    PubMed Central

    El-Sherbiny, Ibrahim M.; El-Baz, Nancy M.; Yacoub, Magdi H.

    2015-01-01

    The 21st century has seen a paradigm shift to inhaled therapy, for both systemic and local drug delivery, due to the lung's favourable properties of a large surface area and high permeability. Pulmonary drug delivery possesses many advantages, including non-invasive route of administration, low metabolic activity, control environment for systemic absorption and avoids first bypass metabolism. However, because the lung is one of the major ports of entry, it has multiple clearance mechanisms, which prevent foreign particles from entering the body. Although these clearance mechanisms maintain the sterility of the lung, clearance mechanisms can also act as barriers to the therapeutic effectiveness of inhaled drugs. This effectiveness is also influenced by the deposition site and delivered dose. Particulate-based drug delivery systems have emerged as an innovative and promising alternative to conventional inhaled drugs to circumvent pulmonary clearance mechanisms and provide enhanced therapeutic efficiency and controlled drug release. The principle of multiple pulmonary clearance mechanisms is reviewed, including mucociliary, alveolar macrophages, absorptive, and metabolic degradation. This review also discusses the current approaches and formulations developed to achieve optimal pulmonary drug delivery systems. PMID:26779496

  7. Targeted Delivery of Chemotherapeutic Agents Using Improved Radiosensitive Liquid Core Microcapsules and Assessment of Their Antitumor Effect

    SciTech Connect

    Harada, Satoshi Ehara, Shigeru; Ishii, Keizo; Yamazaki, Hiromichi; Matsuyama, Shigeo; Sato, Takahiro; Oikawa, Shyoichi; Kamiya, Tomihiro; Arakawa, Kazuo; Yokota, Wataru; Sera, Koichiro; Ito, Jyun

    2009-10-01

    Purpose: Radiation-sensitive microcapsules composed of alginate and hyaluronic acid are being developed. We report the development of improved microcapsules that were prepared using calcium- and yttrium-induced polymerization. We previously reported on the combined antitumor effect of carboplatin-containing microcapsules and radiotherapy. Methods and Materials: We mixed a 0.1% (wt/vol) solution of hyaluronic acid with a 0.2% alginate solution. Carboplatin (l mg) and indocyanine green (12.5 {mu}g) were added to this mixture, and the resultant material was used for capsule preparation. The capsules were prepared by spraying the material into a mixture containing a 4.34% CaCl{sub 2} solution supplemented with 0-0.01% yttrium. These capsules were irradiated with single doses of 0.5, 1.0, 1.5, or 2 Gy {sup 60}Co {gamma}-rays. Immediately after irradiation, the frequency of microcapsule decomposition was determined using a microparticle-induced X-ray emission camera. The amount of core content released was estimated by particle-induced X-ray emission and colorimetric analysis with 0.25% indocyanine green. The antitumor effect of the combined therapy was determined by monitoring its effects on the diameter of an inoculated Meth A fibrosarcoma. Results: Microcapsules that had been polymerized using a 4.34% CaCl{sub 2} solution supplemented with 5.0 x 10{sup -3}% (10{sup -3}% meant or 10%{sup -3}) yttrium exhibited the maximal decomposition, and the optimal release of core content occurred after 2-Gy irradiation. The microcapsules exhibited a synergistic antitumor effect combined with 2-Gy irradiation and were associated with reduced adverse effects. Conclusion: The results of our study have shown that our liquid core microcapsules can be used in radiotherapy for targeted delivery of chemotherapeutic agents.

  8. Applications of chitosan nanoparticles in drug delivery.

    PubMed

    Tajmir-Riahi, H A; Nafisi, Sh; Sanyakamdhorn, S; Agudelo, D; Chanphai, P

    2014-01-01

    We have reviewed the binding affinities of several antitumor drugs doxorubicin (Dox), N-(trifluoroacetyl) doxorubicin (FDox), tamoxifen (Tam), 4-hydroxytamoxifen (4-Hydroxytam), and endoxifen (Endox) with chitosan nanoparticles of different sizes (chitosan-15, chitosan-100, and chitosan-200 KD) in order to evaluate the efficacy of chitosan nanocarriers in drug delivery systems. Spectroscopic and molecular modeling studies showed the binding sites and the stability of drug-polymer complexes. Drug-chitosan complexation occurred via hydrophobic and hydrophilic contacts as well as H-bonding network. Chitosan-100 KD was the more effective drug carrier than the chitosan-15 and chitosan-200 KD. PMID:24567139

  9. The therapeutic potential of vaginal drug delivery in the treatment of cervical cancer.

    PubMed

    McConville, Christopher

    2015-01-01

    Cervical cancer is usually treated by surgery, with the more advanced cancers requiring adjuvant chemo or radiotherapy. Its location makes it easily accessible through the vagina for the localized delivery of chemotherapeutic drugs. Localized delivery has the advantage of direct delivery to the site of action resulting in a lower dose being required and a reduction in systemic side effects. This approach would be advantageous in fertility-sparing surgery, where by localized delivery could be used to reduce tumor size allowing for a much smaller tumor to be removed, reducing the risk of preterm birth. Furthermore, localized delivery could be used after surgery to reduce the risk of recurrence, which is significantly higher in fertility-sparing surgery compared with standard surgery. PMID:26001173

  10. Drug Delivery Strategies of Chemical CDK Inhibitors.

    PubMed

    Alvira, Daniel; Mondragón, Laura

    2016-01-01

    The pharmacological use of new therapeutics is often limited by a safe and effective drug-delivery system. In this sense, new chemical CDK inhibitors are not an exception. Nanotechnology may be able to solve some of the main problems limiting cancer treatments such as more specific delivery of therapeutics and reduction of toxic secondary effects. It provides new delivery systems able to specifically target cancer cells and release the active molecules in a controlled fashion. Specifically, silica mesoporous supports (SMPS) have emerged as an alternative for more classical drug delivery systems based on polymers. In this chapter, we describe the synthesis of a SMPS containing the CDK inhibitor roscovitine as cargo molecule and the protocols for confirmation of the proper cargo release of the nanoparticles in cell culture employing cell viability, cellular internalization, and cell death induction studies. PMID:26231714

  11. Nanostructured nanoparticles of self-assembled lipid pro-drugs as a route to improved chemotherapeutic agents

    NASA Astrophysics Data System (ADS)

    Sagnella, Sharon M.; Gong, Xiaojuan; Moghaddam, Minoo J.; Conn, Charlotte E.; Kimpton, Kathleen; Waddington, Lynne J.; Krodkiewska, Irena; Drummond, Calum J.

    2011-03-01

    We demonstrate that oral delivery of self-assembled nanostructured nanoparticles consisting of 5-fluorouracil (5-FU) lipid prodrugs results in a highly effective, target-activated, chemotherapeutic agent, and offers significantly enhanced efficacy over a commercially available alternative that does not self-assemble. The lipid prodrug nanoparticles have been found to significantly slow the growth of a highly aggressive mouse 4T1 breast tumour, and essentially halt the growth of a human MDA-MB-231 breast tumour in mouse xenografts. Systemic toxicity is avoided as prodrug activation requires a three-step, enzymatic conversion to 5-FU, with the third step occurring preferentially at the tumour site. Additionally, differences in the lipid prodrug chemical structure and internal nanostructure of the nanoparticle dictate the enzymatic conversion rate and can be used to control sustained release profiles. Thus, we have developed novel oral nanomedicines that combine sustained release properties with target-selective activation.

  12. Nanostructured nanoparticles of self-assembled lipid pro-drugs as a route to improved chemotherapeutic agents

    SciTech Connect

    Sagnella, Sharon M.; Gong, Xiaojuan; Moghaddam, Minoo J.; Conn, Charlotte E.; Kimpton, Kathleen; Waddington, Lynne J.; Krodkiewska, Irena; Drummond, Calum J.

    2014-09-24

    We demonstrate that oral delivery of self-assembled nanostructured nanoparticles consisting of 5-fluorouracil (5-FU) lipid prodrugs results in a highly effective, target-activated, chemotherapeutic agent, and offers significantly enhanced efficacy over a commercially available alternative that does not self-assemble. The lipid prodrug nanoparticles have been found to significantly slow the growth of a highly aggressive mouse 4T1 breast tumour, and essentially halt the growth of a human MDA-MB-231 breast tumour in mouse xenografts. Systemic toxicity is avoided as prodrug activation requires a three-step, enzymatic conversion to 5-FU, with the third step occurring preferentially at the tumour site. Additionally, differences in the lipid prodrug chemical structure and internal nanostructure of the nanoparticle dictate the enzymatic conversion rate and can be used to control sustained release profiles. Thus, we have developed novel oral nanomedicines that combine sustained release properties with target-selective activation.

  13. Engineered Polymers for Advanced Drug Delivery

    PubMed Central

    Kim, Sungwon; Kim, Jong-Ho; Jeon, Oju; Kwon, Ick Chan; Park, Kinam

    2009-01-01

    Engineered polymers have been utilized for developing advanced drug delivery systems. The development of such polymers has caused advances in polymer chemistry, which, in turn, has resulted in smart polymers that can respond to changes in environmental condition, such as temperature, pH, and biomolecules. The responses vary widely from swelling/deswelling to degradation. Drug-polymer conjugates and drug-containing nano/micro-particles have been used for drug targeting. Engineered polymers and polymeric systems have also been used in new areas, such as molecular imaging as well as in nanotechnology. This review examines the engineered polymers that have been used as traditional drug delivery and as more recent applications in nanotechnology. PMID:18977434

  14. Liposomes as delivery systems for antineoplastic drugs

    NASA Astrophysics Data System (ADS)

    Medina, Luis Alberto

    2014-11-01

    Liposome drug formulations are defined as pharmaceutical products containing active drug substances encapsulated within the lipid bilayer or in the interior aqueous space of the liposomes. The main importance of this drug delivery system is based on its drastic reduction in systemic dose and concomitant systemic toxicity that in comparison with the free drug, results in an improvement of patient compliance and in a more effective treatment. There are several therapeutic drugs that are potential candidates to be encapsulated into liposomes; particular interest has been focused in therapeutic and antineoplastic drugs, which are characterized for its low therapeutic index and high systemic toxicity. The use of liposomes as drug carriers has been extensively justified and the importance of the development of different formulations or techniques to encapsulate therapeutic drugs has an enormous value in benefit of patients affected by neoplastic diseases.

  15. Engineered inorganic nanoparticles for drug delivery applications.

    PubMed

    Ojea-Jiménez, Isaac; Comenge, Joan; García-Fernández, Lorena; Megson, Zoë A; Casals, Eudald; Puntes, Victor F

    2013-06-01

    Inorganic nanoparticles (NPs) currently have immense potential as drug delivery vectors due to their unique physicochemical properties such as high surface area per unit volume, their optical and magnetic uniqueness and the ability to be functionalized with a large number of ligands to enhance their affinity towards target molecules. These features, together with the therapeutic activity of some drugs, render the combination of these two entities (NP-drug) as an attractive alternative in the area of drug delivery. One of the major advantages of these conjugates is the possibility to have a local delivery of the drug, thus reducing systemic side effects and enabling a higher efficiency of the therapeutic molecule. This review highlights the direct implications of nanoscale particles in the development of drug delivery systems. In more detail, it is also remarked the extensive use of inorganic NPs for targeted cancer therapies. As the range of nanoparticles and their applications continues to increase, human safety concerns are gaining importance, which makes it necessary to better understand the potential toxicity hazards of these materials. PMID:23116108

  16. Chitosan: a propitious biopolymer for drug delivery.

    PubMed

    Duttagupta, Dibyangana S; Jadhav, Varsha M; Kadam, Vilasrao J

    2015-01-01

    Scientists have always been interested in the use of natural polymers for drug delivery. Chitosan, being a natural cationic polysaccharide has received a great deal of attention in the past few years. It is obtained by deacetylation of chitin and is regarded as the second most ubiquitous polymer subsequent to cellulose on earth. Unlike other natural polymers, the cationic charge possessed by chitosan is accountable for imparting interesting physical and chemical properties. Chitosan has been widely exploited for its mucoadhesive character, permeation enhancing properties and controlled release of drugs. Moreover it's non-toxic, biocompatible and biodegradable properties make it a good candidate for novel drug delivery system. This review provides an insight on various chitosan based formulations for drug delivery. Some of the current applications of chitosan in areas like ophthalmic, nasal, buccal, sublingual, gastro-retentive, pulmonary, transdermal, colon-specific and vaginal drug delivery have been discussed. In addition, active targeting of drugs to tumor cells using chitosan has been described. Lastly a brief section covering the safety aspects of chitosan has also been reviewed. PMID:25761010

  17. Trojan Microparticles for Drug Delivery

    PubMed Central

    Anton, Nicolas; Jakhmola, Anshuman; Vandamme, Thierry F.

    2012-01-01

    During the last decade, the US Food and Drug Administration (FDA) have regulated a wide range of products, (foods, cosmetics, drugs, devices, veterinary, and tobacco) which may utilize micro and nanotechnology or contain nanomaterials. Nanotechnology allows scientists to create, explore, and manipulate materials in nano-regime. Such materials have chemical, physical, and biological properties that are quite different from their bulk counterparts. For pharmaceutical applications and in order to improve their administration (oral, pulmonary and dermal), the nanocarriers can be spread into microparticles. These supramolecular associations can also modulate the kinetic releases of drugs entrapped in the nanoparticles. Different strategies to produce these hybrid particles and to optimize the release kinetics of encapsulated drugs are discussed in this review. PMID:24300177

  18. A Novel Combined Approach of Short-Chain Sphingolipids and Thermosensitive Liposomes for Improved Drug Delivery to Tumor Cells.

    PubMed

    Haeri, Azadeh; Pedrosa, Lilia R C; Ten Hagen, Timo L M; Dadashzadeh, Simin; Koning, Gerben A

    2016-04-01

    Despite the advantages of liposomal drug delivery, the bioavailability of the chemotherapeutic drugs to tumor cells is limited by their slow release from nanocarriers and low drug permeability across cell membranes. Drug encapsulation into stealth thermosensitive liposomes can improve drug delivery to tumors by combining efficient accumulation at tumors and the active release of the payload following remote heat triggering. Short-chain sphingolipids are known to enhance cellular uptake of amphiphilic drugs. We hypothesized that short-chain sphingolipids could be utilized to further improve intracellular drug delivery from a thermoresponsive formulation by enhancing the cell membrane passage of released drug. The following two strategies were investigated: (1) co-delivery of C8-glucosylceramide and doxorubicin within the thermosensitive liposomes and (2) pretreatment with glucosylceramide-enriched drug-free liposomes and subsequent treatment with doxorubicin loaded thermosensitive liposomes. Liposomes were prepared and extensively characterized. Drug uptake, cell cytotoxicity and live cell imaging were performed under normothermic and hyperthermic conditions in melanoma cells. In these studies, hyperthermia improved drug delivery from doxorubicin loaded thermosensitive formulations. However, the results from cell experiments indicated that there was no additional benefit in the co-delivery strategy using doxorubicin loaded glucosylceramide-enriched thermosensitive liposomes. In contrast, cellular studies showed significantly higher doxorubicin internalization in the pretreatment strategy. One-hour exposure of the cells to C8-glucosylceramide before applying hyperthermia caused improved doxorubicin uptake and cytotoxicity as well as an almost instantaneous cellular entry of the doxorubicin released from thermosensitive liposomes. This novel, two-step drug delivery approach can be potentially beneficial for the intracellular delivery of cell impermeable

  19. Nanoparticles in the ocular drug delivery

    PubMed Central

    Zhou, Hong-Yan; Hao, Ji-Long; Wang, Shuang; Zheng, Yu; Zhang, Wen-Song

    2013-01-01

    Ocular drug transport barriers pose a challenge for drug delivery comprising the ocular surface epithelium, the tear film and internal barriers of the blood-aqueous and blood-retina barriers. Ocular drug delivery efficiency depends on the barriers and the clearance from the choroidal, conjunctival vessels and lymphatic. Traditional drug administration reduces the clinical efficacy especially for poor water soluble molecules and for the posterior segment of the eye. Nanoparticles (NPs) have been designed to overcome the barriers, increase the drug penetration at the target site and prolong the drug levels by few internals of drug administrations in lower doses without any toxicity compared to the conventional eye drops. With the aid of high specificity and multifunctionality, DNA NPs can be resulted in higher transfection efficiency for gene therapy. NPs could target at cornea, retina and choroid by surficial applications and intravitreal injection. This review is concerned with recent findings and applications of NPs drug delivery systems for the treatment of different eye diseases. PMID:23826539

  20. Genetically engineered nanocarriers for drug delivery

    PubMed Central

    Shi, Pu; Gustafson, Joshua A; MacKay, J Andrew

    2014-01-01

    Cytotoxicity, low water solubility, rapid clearance from circulation, and off-target side-effects are common drawbacks of conventional small-molecule drugs. To overcome these shortcomings, many multifunctional nanocarriers have been proposed to enhance drug delivery. In concept, multifunctional nanoparticles might carry multiple agents, control release rate, biodegrade, and utilize target-mediated drug delivery; however, the design of these particles presents many challenges at the stage of pharmaceutical development. An emerging solution to improve control over these particles is to turn to genetic engineering. Genetically engineered nanocarriers are precisely controlled in size and structure and can provide specific control over sites for chemical attachment of drugs. Genetically engineered drug carriers that assemble nanostructures including nanoparticles and nanofibers can be polymeric or non-polymeric. This review summarizes the recent development of applications in drug and gene delivery utilizing nanostructures of polymeric genetically engineered drug carriers such as elastin-like polypeptides, silk-like polypeptides, and silk-elastin-like protein polymers, and non-polymeric genetically engineered drug carriers such as vault proteins and viral proteins. PMID:24741309

  1. Current perspectives on intrathecal drug delivery

    PubMed Central

    Bottros, Michael M; Christo, Paul J

    2014-01-01

    Advances in intrathecal analgesia and intrathecal drug delivery systems have allowed for a range of medications to be used in the control of pain and spasticity. This technique allows for reduced medication doses that can decrease the side effects typically associated with oral or parenteral drug delivery. Recent expert panel consensus guidelines have provided care paths in the treatment of nociceptive, neuropathic, and mixed pain syndromes. While the data for pain relief, adverse effect reduction, and cost-effectiveness with cancer pain control are compelling, the evidence is less clear for noncancer pain, other than spasticity. Physicians should be aware of mechanical, pharmacological, surgical, and patient-specific complications, including possible granuloma formation. Newer intrathecal drug delivery systems may allow for better safety and quality of life outcomes. PMID:25395870

  2. Barriers to drug delivery in solid tumors

    PubMed Central

    Sriraman, Shravan Kumar; Aryasomayajula, Bhawani; Torchilin, Vladimir P

    2014-01-01

    Over the last decade, significant progress has been made in the field of drug delivery. The advent of engineered nanoparticles has allowed us to circumvent the initial limitations to drug delivery such as pharmacokinetics and solubility. However, in spite of significant advances to tumor targeting, an effective treatment strategy for malignant tumors still remains elusive. Tumors possess distinct physiological features which allow them to resist traditional treatment approaches. This combined with the complexity of the biological system presents significant hurdles to the site-specific delivery of therapeutic drugs. One of the key features of engineered nanoparticles is that these can be tailored to execute specific functions. With this review, we hope to provide the reader with a clear understanding and knowledge of biological barriers and the methods to exploit these characteristics to design multifunctional nanocarriers, effect useful dosing regimens and subsequently improve therapeutic outcomes in the clinic. PMID:25068098

  3. Ultrasound-mediated gastrointestinal drug delivery

    PubMed Central

    Schoellhammer, Carl M.; Schroeder, Avi; Maa, Ruby; Lauwers, Gregory Yves; Swiston, Albert; Zervas, Michael; Barman, Ross; DiCiccio, Angela M.; Brugge, William R.; Anderson, Daniel G.; Blankschtein, Daniel; Langer, Robert; Traverso, Giovanni

    2016-01-01

    There is a significant clinical need for rapid and efficient delivery of drugs directly to the site of diseased tissues for the treatment of gastrointestinal (GI) pathologies, in particular, Crohn’s and ulcerative colitis. However, complex therapeutic molecules cannot easily be delivered through the GI tract because of physiologic and structural barriers. We report the use of ultrasound as a modality for enhanced drug delivery to the GI tract, with an emphasis on rectal delivery. Ultrasound increased the absorption of model therapeutics inulin, hydrocortisone, and mesalamine two- to tenfold in ex vivo tissue, depending on location in the GI tract. In pigs, ultrasound induced transient cavitation with negligible heating, leading to an order of magnitude enhancement in the delivery of mesalamine, as well as successful systemic delivery of a macromolecule, insulin, with the expected hypoglycemic response. In a rodent model of chemically induced acute colitis, the addition of ultrasound to a daily mesalamine enema (compared to enema alone) resulted in superior clinical and histological scores of disease activity. In both animal models, ultrasound treatment was well tolerated and resulted in minimal tissue disruption, and in mice, there was no significant effect on histology, fecal score, or tissue inflammatory cytokine levels. The use of ultrasound to enhance GI drug delivery is safe in animals and could augment the efficacy of GI therapies and broaden the scope of agents that could be delivered locally and systemically through the GI tract for chronic conditions such as inflammatory bowel disease. PMID:26491078

  4. Targeting the brain: advances in drug delivery.

    PubMed

    Blumling Iii, James P; Silva, Gabriel A

    2012-09-01

    The blood-brain barrier (BBB) represents a significant obstacle for drug delivery to the brain. Many therapeutics with potential for treating neurological conditions prove incompatible with intravenous delivery simply because of this barrier. Rather than modifying drugs to penetrate the BBB directly, it has proven more efficacious to either physically bypass the barrier or to use specialized delivery vehicles that circumvent BBB regulatory mechanisms. Controlled-release intracranial polymer implants and particle injections are the clinical state of the art with regard to localized delivery, although these approaches can impose significant surgical risks. Focused ultrasound provides a non-invasive alternative that may prove more desirable for acute treatment of brain tumors and other conditions requiring local tissue necrosis. For targeting the brain as a whole, cell-penetrating peptides (CPPs) and molecular trojan horses (MTHs) have demonstrated particular ability as delivery molecules and will likely see increased application. CPPs are not brain specific but offer the potential for efficient traversal of the BBB, and tandem systems with targeting molecules may produce extremely effective brain drug delivery tools. Molecular trojan horses utilize receptor-mediated transcytosis to transport cargo and are thus limited by the quantity of relevant receptors; however, they can be very selective for the BBB endothelium and have shown promise in gene therapy. PMID:23016646

  5. Drug delivery and nanoparticles: Applications and hazards

    PubMed Central

    De Jong, Wim H; Borm, Paul JA

    2008-01-01

    The use of nanotechnology in medicine and more specifically drug delivery is set to spread rapidly. Currently many substances are under investigation for drug delivery and more specifically for cancer therapy. Interestingly pharmaceutical sciences are using nanoparticles to reduce toxicity and side effects of drugs and up to recently did not realize that carrier systems themselves may impose risks to the patient. The kind of hazards that are introduced by using nanoparticles for drug delivery are beyond that posed by conventional hazards imposed by chemicals in classical delivery matrices. For nanoparticles the knowledge on particle toxicity as obtained in inhalation toxicity shows the way how to investigate the potential hazards of nanoparticles. The toxicology of particulate matter differs from toxicology of substances as the composing chemical(s) may or may not be soluble in biological matrices, thus influencing greatly the potential exposure of various internal organs. This may vary from a rather high local exposure in the lungs and a low or neglectable exposure for other organ systems after inhalation. However, absorbed species may also influence the potential toxicity of the inhaled particles. For nanoparticles the situation is different as their size opens the potential for crossing the various biological barriers within the body. From a positive viewpoint, especially the potential to cross the blood brain barrier may open new ways for drug delivery into the brain. In addition, the nanosize also allows for access into the cell and various cellular compartments including the nucleus. A multitude of substances are currently under investigation for the preparation of nanoparticles for drug delivery, varying from biological substances like albumin, gelatine and phospholipids for liposomes, and more substances of a chemical nature like various polymers and solid metal containing nanoparticles. It is obvious that the potential interaction with tissues and cells

  6. Modification of polyethylene glycol onto solid lipid nanoparticles encapsulating a novel chemotherapeutic agent (PK-L4) to enhance solubility for injection delivery

    PubMed Central

    Fang, Yi-Ping; Wu, Pao-Chu; Huang, Yaw-Bin; Tzeng, Cherng-Chyi; Chen, Yeh-Long; Hung, Yu-Han; Tsai, Ming-Jun; Tsai, Yi-Hung

    2012-01-01

    Background The synthetic potential chemotherapeutic agent 3-Chloro-4-[(4-methoxyphenyl) amino]furo[2,3-b]quinoline (PK-L4) is an analog of amsacrine. The half-life of PK-L4 is longer than that of amsacrine; however, PK-L4 is difficult to dissolve in aqueous media, which is problematic for administration by intravenous injection. Aims To utilize solid lipid nanoparticles (SLNs) modified with polyethylene glycol (PEG) to improve the delivery of PK-L4 and investigate its biodistribution behavior after intravenous administration. Results The particle size of the PK-L4-loaded SLNs was 47.3 nm and the size of the PEGylated form was smaller, at 28 nm. The entrapment efficiency (EE%) of PK-L4 in SLNs with and without PEG showed a high capacity of approximately 100% encapsulation. Results also showed that the amount of PK-L4 released over a prolonged period from SLNs both with and without PEG was comparable to the non-formulated group, with 16.48% and 30.04%, respectively, of the drug being released, which fit a zero-order equation. The half-maximal inhibitory concentration values of PK-L4-loaded SLNs with and those without PEG were significantly reduced by 45%–64% in the human lung carcinoma cell line (A549), 99% in the human breast adenocarcinoma cell line with estrogen receptor (MCF7), and 95% in the human breast adenocarcinoma cell line (MDA-MB-231). The amount of PK-L4 released by SLNs with PEG was significantly higher than that from the PK-L4 solution (P < 0.05). After intravenous bolus of the PK-L4-loaded SLNs with PEG, there was a marked significant difference in half-life alpha (0.136 ± 0.046 hours) when compared with the PK-L4 solution (0.078 ± 0.023 hours); also the area under the curve from zero to infinity did not change in plasma when compared to the PK-L4 solution. This demonstrated that PK-L4-loaded SLNs were rapidly distributed from central areas to tissues and exhibited higher accumulation in specific organs. The highest deposition of PK-L4-loaded SLNs

  7. Drug delivery system and breast cancer cells

    NASA Astrophysics Data System (ADS)

    Colone, Marisa; Kaliappan, Subramanian; Calcabrini, Annarica; Tortora, Mariarosaria; Cavalieri, Francesca; Stringaro, Annarita

    2016-06-01

    Recently, nanomedicine has received increasing attention for its ability to improve the efficacy of cancer therapeutics. Nanosized polymer therapeutic agents offer the advantage of prolonged circulation in the blood stream, targeting to specific sites, improved efficacy and reduced side effects. In this way, local, controlled delivery of the drug will be achieved with the advantage of a high concentration of drug release at the target site while keeping the systemic concentration of the drug low, thus reducing side effects due to bioaccumulation. Various drug delivery systems such as nanoparticles, liposomes, microparticles and implants have been demonstrated to significantly enhance the preventive/therapeutic efficacy of many drugs by increasing their bioavailability and targetability. As these carriers significantly increase the therapeutic effect of drugs, their administration would become less cost effective in the near future. The purpose of our research work is to develop a delivery system for breast cancer cells using a microvector of drugs. These results highlight the potential uses of these responsive platforms suited for biomedical and pharmaceutical applications. At the request of all authors of the paper an updated version was published on 12 July 2016. The manuscript was prepared and submitted without Dr. Francesca Cavalieri's contribution and her name was added without her consent. Her name has been removed in the updated and re-published article.

  8. Plasmon resonant liposomes for controlled drug delivery

    NASA Astrophysics Data System (ADS)

    Knights-Mitchell, Shellie S.; Romanowski, Marek

    2015-03-01

    Nanotechnology use in drug delivery promotes a reduction in systemic toxicity, improved pharmacokinetics, and better drug bioavailability. Liposomes continue to be extensively researched as drug delivery systems (DDS) with formulations such as Doxil® and Ambisome® approved by FDA and successfully marketed in the United States. However, the limited ability to precisely control release of active ingredients from these vesicles continues to challenge the broad implementation of this technology. Moreover, the full potential of the carrier to sequester drugs until it can reach its intended target has yet to be realized. Here, we describe a liposomal DDS that releases therapeutic doses of an anticancer drug in response to external stimulus. Earlier, we introduced degradable plasmon resonant liposomes. These constructs, obtained by reducing gold on the liposome surface, facilitate spatial and temporal release of drugs upon laser light illumination that ultimately induces an increase in temperature. In this work, plasmon resonant liposomes have been developed to stably encapsulate and retain doxorubicin at physiological conditions represented by isotonic saline at 37o C and pH 7.4. Subsequently, they are stimulated to release contents either by a 5o C increase in temperature or by laser illumination (760 nm and 88 mW/cm2 power density). Successful development of degradable plasmon resonant liposomes responsive to near-infrared light or moderate hyperthermia can provide a new delivery method for multiple lipophilic and hydrophilic drugs with pharmacokinetic profiles that limit clinical utility.

  9. Recent technologies in pulsatile drug delivery systems

    PubMed Central

    Jain, Deepika; Raturi, Richa; Jain, Vikas; Bansal, Praveen; Singh, Ranjit

    2011-01-01

    Pulsatile drug delivery systems (PDDS) have attracted attraction because of their multiple benefits over conventional dosage forms. They deliver the drug at the right time, at the right site of action and in the right amount, which provides more benefit than conventional dosages and increased patient compliance. These systems are designed according to the circadian rhythm of the body, and the drug is released rapidly and completely as a pulse after a lag time. These products follow the sigmoid release profile characterized by a time period. These systems are beneficial for drugs with chronopharmacological behavior, where nocturnal dosing is required, and for drugs that show the first-pass effect. This review covers methods and marketed technologies that have been developed to achieve pulsatile delivery. Marketed technologies, such as PulsincapTM, Diffucaps®, CODAS®, OROS® and PULSYSTM, follow the above mechanism to render a sigmoidal drug release profile. Diseases wherein PDDS are promising include asthma, peptic ulcers, cardiovascular ailments, arthritis and attention deficit syndrome in children and hypercholesterolemia. Pulsatile drug delivery systems have the potential to bring new developments in the therapy of many diseases. PMID:23507727

  10. Drug delivery system and breast cancer cells

    NASA Astrophysics Data System (ADS)

    Colone, Marisa; Kaliappan, Subramanian; Calcabrini, Annarica; Tortora, Mariarosaria; Cavalieri, Francesca; Stringaro, Annarita

    2016-06-01

    Recently, nanomedicine has received increasing attention for its ability to improve the efficacy of cancer therapeutics. Nanosized polymer therapeutic agents offer the advantage of prolonged circulation in the blood stream, targeting to specific sites, improved efficacy and reduced side effects. In this way, local, controlled delivery of the drug will be achieved with the advantage of a high concentration of drug release at the target site while keeping the systemic concentration of the drug low, thus reducing side effects due to bioaccumulation. Various drug delivery systems such as nanoparticles, liposomes, microparticles and implants have been demonstrated to significantly enhance the preventive/therapeutic efficacy of many drugs by increasing their bioavailability and targetability. As these carriers significantly increase the therapeutic effect of drugs, their administration would become less cost effective in the near future. The purpose of our research work is to develop a delivery system for breast cancer cells using a microvector of drugs. These results highlight the potential uses of these responsive platforms suited for biomedical and pharmaceutical applications.

  11. Transungual drug delivery: current status.

    PubMed

    Elkeeb, Rania; AliKhan, Ali; Elkeeb, Laila; Hui, Xiaoying; Maibach, Howard I

    2010-01-15

    Topical therapy is highly desirable in treating nail disorders due to its localized effects, which results in minimal adverse systemic events and possibly improved adherence. However, the effectiveness of topical therapies is limited by minimal drug permeability through the nail plate. Current research on nail permeation that focuses on altering the nail plate barrier by means of chemical treatments, penetration enhancers as well as physical and mechanical methods is reviewed. A new method of nail sampling is examined. Finally limitations of current ungual drug permeability studies are briefly discussed. PMID:19819318

  12. Disulfide-based multifunctional conjugates for targeted theranostic drug delivery.

    PubMed

    Lee, Min Hee; Sessler, Jonathan L; Kim, Jong Seung

    2015-11-17

    Theranostics, chemical entities designed to combine therapeutic effects and imaging capability within one molecular system, have received considerable attention in recent years. Much of this interest reflects the promise inherent in personalized medicine, including disease-targeted treatments for cancer patients. One important approach to realizing this latter promise involves the development of so-called theranostic conjugates, multicomponent constructs that selectively target cancer cells and deliver cytotoxic agents while producing a readily detectable signal that can be monitored both in vitro and in vivo. This requires the synthesis of relatively complex systems comprising imaging reporters, masked chemotherapeutic drugs, cleavable linkers, and cancer targeting ligands. Ideally, the cleavage process should take place within or near cancer cells and be activated by cellular components that are associated with cancer states or specifically expressed at a higher level in cancer cells. Among the cleavable linkers currently being explored for the construction of such localizing conjugates, disulfide bonds are particularly attractive. This is because disulfide bonds are stable in most blood pools but are efficiently cleaved by cellular thiols, including glutathione (GSH) and thioredoxin (Trx), which are generally found at elevated levels in tumors. When disulfide bonds are linked to fluorophores, changes in emission intensity or shifts in the emission maxima are typically seen upon cleavage as the result of perturbations to internal charge transfer (ICT) processes. In well-designed systems, this allows for facile imaging. In this Account, we summarize our recent studies involving disulfide-based fluorescent drug delivery conjugates, including preliminary tests of their biological utility in vitro and in vivo. To date, a variety of chemotherapeutic agents, such as doxorubicin, gemcitabine, and camptothecin, have been used to create disulfide-based conjugates, as have

  13. Aptamers for Targeted Drug Delivery

    PubMed Central

    Ray, Partha; White, Rebekah R.

    2010-01-01

    Aptamers are a class of therapeutic oligonucleotides that form specific three-dimensional structures that are dictated by their sequences. They are typically generated by an iterative screening process of complex nucleic acid libraries employing a process termed Systemic Evolution of Ligands by Exponential Enrichment (SELEX). SELEX has traditionally been performed using purified proteins, and cell surface receptors may be challenging to purify in their properly folded and modified conformations. Therefore, relatively few aptamers have been generated that bind cell surface receptors. However, improvements in recombinant fusion protein technology have increased the availability of receptor extracellular domains as purified protein targets, and the development of cell-based selection techniques has allowed selection against surface proteins in their native configuration on the cell surface. With cell-based selection, a specific protein target is not always chosen, but selection is performed against a target cell type with the goal of letting the aptamer choose the target. Several studies have demonstrated that aptamers that bind cell surface receptors may have functions other than just blocking receptor-ligand interactions. All cell surface proteins cycle intracellularly to some extent, and many surface receptors are actively internalized in response to ligand binding. Therefore, aptamers that bind cell surface receptors have been exploited for the delivery of a variety of cargoes into cells. This review focuses on recent progress and current challenges in the field of aptamer-mediated delivery.

  14. Nanotechnology-Based Drug Delivery Systems for Melanoma Antitumoral Therapy: A Review

    PubMed Central

    Rigon, Roberta Balansin; Oyafuso, Márcia Helena; Fujimura, Andressa Terumi; do Prado, Alice Haddad; Gremião, Maria Palmira Daflon

    2015-01-01

    Melanoma (MEL) is a less common type of skin cancer, but it is more aggressive with a high mortality rate. The World Cancer Research Fund International (GLOBOCAN 2012) estimates that there were 230,000 new cases of MEL in the world in 2012. Conventional MEL treatment includes surgery and chemotherapy, but many of the chemotherapeutic agents used present undesirable properties. Drug delivery systems are an alternative strategy by which to carry antineoplastic agents. Encapsulated drugs are advantageous due to such properties as high stability, better bioavailability, controlled drug release, a long blood circulation time, selective organ or tissue distribution, a lower total required dose, and minimal toxic side effects. This review of scientific research supports applying a nanotechnology-based drug delivery system for MEL therapy. PMID:26078967

  15. Nanotechnology-Based Drug Delivery Systems for Melanoma Antitumoral Therapy: A Review.

    PubMed

    Rigon, Roberta Balansin; Oyafuso, Márcia Helena; Fujimura, Andressa Terumi; Gonçalez, Maíra Lima; do Prado, Alice Haddad; Gremião, Maria Palmira Daflon; Chorilli, Marlus

    2015-01-01

    Melanoma (MEL) is a less common type of skin cancer, but it is more aggressive with a high mortality rate. The World Cancer Research Fund International (GLOBOCAN 2012) estimates that there were 230,000 new cases of MEL in the world in 2012. Conventional MEL treatment includes surgery and chemotherapy, but many of the chemotherapeutic agents used present undesirable properties. Drug delivery systems are an alternative strategy by which to carry antineoplastic agents. Encapsulated drugs are advantageous due to such properties as high stability, better bioavailability, controlled drug release, a long blood circulation time, selective organ or tissue distribution, a lower total required dose, and minimal toxic side effects. This review of scientific research supports applying a nanotechnology-based drug delivery system for MEL therapy. PMID:26078967

  16. PH responsive polypeptide based polymeric micelles for anticancer drug delivery.

    PubMed

    Zhao, Dongping; Li, Bingqiang; Han, Jiaming; Yang, Yue; Zhang, Xinchen; Wu, Guolin

    2015-09-01

    A pH-responsive polymeric micelle based on poly(aspartamide) derivative was explored as an efficient acid-triggered anticancer drug delivery system. Poly(α,β-l-asparthydrazide) (PAHy) was prepared by aminolysis reaction of polysuccinimide with hydrazine hydrate. Poly(ethylene glycol) and aliphatic chain (C18) were conjugated onto PAHy to afford an amphiphilic copolymer with acid-liable hydrazone bonds. The structure of the resulting copolymer and its self-assembled micelles were confirmed by (1) H NMR, FTIR, DLS, and TEM. Furthermore, doxorubicin (DOX) was loaded into the polymeric micelles via the hydrophobic interaction between the C18 group and DOX molecules, and the π-π staking between the hydrazone conjugated DOX and free DOX molecules. Results showed that the DOX loaded nanoparticle (NP) was relatively stable under physiological conditions, while the DOX was quickly released in response to acidity due to the shedding of mPEG shells and dissociating of C18 segments because of the pH-cleavage of intermediate hydrazone bonds. In addition, the DOX loaded micelles presented a high cytotoxic activity against tumor cells in vitro. This pH responsive NP has appeared highly promising for the targeted intracellular delivery of hydrophobic chemotherapeutics in cancer therapy. PMID:25689362

  17. A Fibrous Localized Drug Delivery Platform with NIR-Triggered and Optically Monitored Drug Release.

    PubMed

    Liu, Heng; Fu, Yike; Li, Yangyang; Ren, Zhaohui; Li, Xiang; Han, Gaorong; Mao, Chuanbin

    2016-09-01

    Implantable localized drug delivery systems (LDDSs) with intelligent functionalities have emerged as a powerful chemotherapeutic platform in curing cancer. Developing LDDSs with rationally controlled drug release and real-time monitoring functionalities holds promise for personalized therapeutic protocols but suffers daunting challenges. To overcome such challenges, a series of porous Yb(3+)/Er(3+) codoped CaTiO3 (CTO:Yb,Er) nanofibers, with specifically designed surface functionalization, were synthesized for doxorubicin (DOX) delivery. The content of DOX released could be optically monitored by increase in the intensity ratio of green to red emission (I550/I660) of upconversion photoluminescent nanofibers under 980 nm near-infrared (NIR) excitation owing to the fluorescence resonance energy transfer (FRET) effect between DOX molecules and the nanofibers. More importantly, the 808 nm NIR irradiation enabled markedly accelerated DOX release, confirming representative NIR-triggered drug release properties. In consequence, such CTO:Yb,Er nanofibers presented significantly enhanced in vitro anticancer efficacy under NIR irradiation. This study has thus inspired another promising fibrous LDDS platform with NIR-triggered and optics-monitored DOX releasing for personalized tumor chemotherapy. PMID:27557281

  18. Sericin/Dextran Injectable Hydrogel as an Optically Trackable Drug Delivery System for Malignant Melanoma Treatment.

    PubMed

    Liu, Jia; Qi, Chao; Tao, Kaixiong; Zhang, Jinxiang; Zhang, Jian; Xu, Luming; Jiang, Xulin; Zhang, Yunti; Huang, Lei; Li, Qilin; Xie, Hongjian; Gao, Jinbo; Shuai, Xiaoming; Wang, Guobin; Wang, Zheng; Wang, Lin

    2016-03-01

    Severe side effects of cancer chemotherapy prompt developing better drug delivery systems. Injectable hydrogels are an effective site-target system. For most of injectable hydrogels, once delivered in vivo, some properties including drug release and degradation, which are critical to chemotherapeutic effects and safety, are challenging to monitor. Developing a drug delivery system for effective cancer therapy with in vivo real-time noninvasive trackability is highly desired. Although fluorescence dyes are used for imaging hydrogels, the cytotoxicity limits their applications. By using sericin, a natural photoluminescent protein from silk, we successfully synthesized a hydrazone cross-linked sericin/dextran injectable hydrogel. This hydrogel is biodegradable and biocompatible. It achieves efficient drug loading and controlled release of both macromolecular and small molecular drugs. Notably, sericin's photoluminescence from this hydrogel is directly and stably correlated with its degradation, enabling long-term in vivo imaging and real-time monitoring of the remaining drug. The hydrogel loaded with Doxorubicin significantly suppresses tumor growth. Together, the work demonstrates the efficacy of this drug delivery system, and the in vivo effectiveness of this sericin-based optical monitoring strategy, providing a potential approach for improving hydrogel design toward optimal efficiency and safety of chemotherapies, which may be widely applicable to other drug delivery systems. PMID:26900631

  19. Drug delivery applications with ethosomes.

    PubMed

    Ainbinder, D; Paolino, D; Fresta, M; Touitou, E

    2010-10-01

    Ethosomes are specially tailored vesicular carriers able to efficiently deliver various molecules with different physicochemical properties into deep skin layers and across the skin. This paper reviews the unique characteristics of the ethosomal carriers, focusing on work carried out with drug containing ethosomal systems in animal models and in clinical studies. The paper concludes with a discussion on the safety of the ethosomal system applications. PMID:21329048

  20. Poly(hydroxy acids) in drug delivery.

    PubMed

    Juni, K; Nakano, M

    1987-01-01

    Poly(hydroxy acids) so far have been examined for use in drug delivery in limited number, while the advantageous use of the polymers has been recognized due to their biodegradability and biocompatibility. Homo- and copolymers of lactic acid and glycolic acid have been studied in drug delivery by many workers, while homo- and copolymers of epsilon-caprolactone have been studied by only one group of workers. Although poly-hydroxybutyric acid had been found to be a naturally occurring polymer, examination as to the use of the polymer in drug delivery is rather recent and reports are still limited. In the present article, the use of poly(hydroxy acids) including homo- and copolymers of lactic acid and glycolic acid, polycaprolactone, and poly-beta-hydroxybutyric acid in drug delivery is reviewed. Physicochemical properties, biodegradability, and biocompatibility of the polymers, and evaluations in vitro and in vivo of specific dosage forms using the polymers, are included. The most recent work in our laboratories on the use of polyactic acid and poly-beta-hydroxybutyric acid is also included. PMID:3549007

  1. Recent Perspectives in Ocular Drug Delivery

    PubMed Central

    Gaudana, Ripal; Jwala, J.; Boddu, Sai H. S.; Mitra, Ashim K.

    2015-01-01

    Anatomy and physiology of the eye makes it a highly protected organ. Designing an effective therapy for ocular diseases, especially for the posterior segment, has been considered as a formidable task. Limitations of topical and intravitreal route of administration have challenged scientists to find alternative mode of administration like periocular routes. Transporter targeted drug delivery has generated a great deal of interest in the field because of its potential to overcome many barriers associated with current therapy. Application of nanotechnology has been very promising in the treatment of a gamut of diseases. In this review, we have briefly discussed several ocular drug delivery systems such as microemulsions, nanosuspensions, nanoparticles, liposomes, niosomes, dendrimers, implants, and hydrogels. Potential for ocular gene therapy has also been described in this article. In near future, a great deal of attention will be paid to develop non-invasive sustained drug release for both anterior and posterior segment eye disorders. A better understanding of nature of ocular diseases, barriers and factors affecting in vivo performance, would greatly drive the development of new delivery systems. Current momentum in the invention of new drug delivery systems hold a promise towards much improved therapies for the treatment of vision threatening disorders. PMID:18758924

  2. Reversing drug resistance of soft tumor-repopulating cells by tumor cell-derived chemotherapeutic microparticles.

    PubMed

    Ma, Jingwei; Zhang, Yi; Tang, Ke; Zhang, Huafeng; Yin, Xiaonan; Li, Yong; Xu, Pingwei; Sun, Yanling; Ma, Ruihua; Ji, Tiantian; Chen, Junwei; Zhang, Shuang; Zhang, Tianzhen; Luo, Shunqun; Jin, Yang; Luo, Xiuli; Li, Chengyin; Gong, Hongwei; Long, Zhixiong; Lu, Jinzhi; Hu, Zhuowei; Cao, Xuetao; Wang, Ning; Yang, Xiangliang; Huang, Bo

    2016-06-01

    Developing novel approaches to reverse the drug resistance of tumor-repopulating cells (TRCs) or stem cell-like cancer cells is an urgent clinical need to improve outcomes of cancer patients. Here we show an innovative approach that reverses drug resistance of TRCs using tumor cell-derived microparticles (T-MPs) containing anti-tumor drugs. TRCs, by virtue of being more deformable than differentiated cancer cells, preferentially take up T-MPs that release anti-tumor drugs after entering cells, which in turn lead to death of TRCs. The underlying mechanisms include interfering with drug efflux and promoting nuclear entry of the drugs. Our findings demonstrate the importance of tumor cell softness in uptake of T-MPs and effectiveness of a novel approach in reversing drug resistance of TRCs with promising clinical applications. PMID:27167569

  3. Strategies for antimicrobial drug delivery to biofilm.

    PubMed

    Martin, Claire; Low, Wan Li; Gupta, Abhishek; Amin, Mohd Cairul Iqbal Mohd; Radecka, Iza; Britland, Stephen T; Raj, Prem; Kenward, Ken M A

    2015-01-01

    Biofilms are formed by the attachment of single or mixed microbial communities to a variety of biological and/or synthetic surfaces. Biofilm micro-organisms benefit from many advantages of the polymicrobial environment including increased resistance against antimicrobials and protection against the host organism's defence mechanisms. These benefits stem from a number of structural and physiological differences between planktonic and biofilm-resident microbes, but two main factors are the presence of extracellular polymeric substances (EPS) and quorum sensing communication. Once formed, biofilms begin to synthesise EPS, a complex viscous matrix composed of a variety of macromolecules including proteins, lipids and polysaccharides. In terms of drug delivery strategies, it is the EPS that presents the greatest barrier to diffusion for drug delivery systems and free antimicrobial agents alike. In addition to EPS synthesis, biofilm-based micro-organisms can also produce small, diffusible signalling molecules involved in cell density-dependent intercellular communication, or quorum sensing. Not only does quorum sensing allow microbes to detect critical cell density numbers, but it also permits co-ordinated behaviour within the biofilm, such as iron chelation and defensive antibiotic activities. Against this backdrop of microbial defence and cell density-specific communication, a variety of drug delivery systems have been developed to deliver antimicrobial agents and antibiotics to extracellular and/or intracellular targets, or more recently, to interfere with the specific mechanisms of quorum sensing. Successful delivery strategies have employed lipidic and polymeric-based formulations such as liposomes and cyclodextrins respectively, in addition to inorganic carriers e.g. metal nanoparticles. This review will examine a range of drug delivery systems and their application to biofilm delivery, as well as pharmaceutical formulations with innate antimicrobial properties

  4. Suppression of PRKAR1A expression enhances anti-proliferative and apoptotic effects of protein kinase inhibitors and chemotherapeutic drugs on cholangiocarcinoma cells.

    PubMed

    Loilome, Watcharin; Juntana, Sirinun; Pinitsoontorn, Chadamas; Namwat, Nisana; Tassaneeyakul, Wichittra; Yongvanit, Puangrat

    2012-01-01

    Suppression of protein kinase A regulatory subunit 1 alpha (PRKAR1A) has been proven to inhibit cholangiocarcinoma (CCA) cell growth and enhance apoptosis. In the present study, we aimed to determine synergistic and/or additive effects of chemotherapeutic agents, including protein kinase inhibitors (i.e. sorafenib, sunitinib, gefitinib, Met inhibitor) and conventional chemotherapeutic drugs (i.e. 5-fluorouracil, doxorubicin, paclitaxel, gemcitabine), in PRKARIA knockdown CCA cell lines. The results revealed that PRKAR1A suppressed CCA cell lines demonstrated enhanced sensitivity to some chemotherapeutic drugs when compared to control cells. Moreover, PRKAR1A knockdown in combination with either sorafenib or 5-fluorouracil increased apoptotic effects on CCA cell lines. Therefore, selective inhibition of PRKAR1A appears to enhance the growth inhibitory effects of chemotherapeutic drugs as well as induce apoptotic cell death. Our findings suggest that additional suppression of PRKAR1A expression may increase the efficacy of conventional CCA chemotherapeutic treatment. Clinical studies in CCA patients now need to be conducted. PMID:23480756

  5. Chemotherapeutic efficiency of drugs in vitro: Comparison of doxorubicin exposure in 3D and 2D culture matrices.

    PubMed

    Casey, A; Gargotti, M; Bonnier, F; Byrne, H J

    2016-06-01

    The interest in the use of 3D matrices for in vitro analysis, with a view to increasing the relevance of in vitro studies and reducing the dependence on in vivo studies, has been growing in recent years. Cells grown in a 3D in vitro matrix environment have been reported to exhibit significantly different properties to those in a conventional 2D culture environment. However, comparison of 2D and 3D cell culture models have recently been noted to result in differing responses of cytotoxic assays, without any associated change in viability. The effect was attributed to differing conversion rates and effective concentrations of the resazurin assay in 2D and 3D environments, rather than differences in cellular metabolism. In this study, the efficacy of a chemotherapeutic agent, doxorubicin, is monitored and compared in conventional 2D and 3D collagen gel exposures of immortalized human cervical cells. Viability was monitored with the aid of the Alamar Blue assay and drug internalisation was verified using confocal microscopy. Drug uptake and retention within the collagen matrix was monitored by absorption spectroscopy. The viability studies showed apparent differences between the 2D and 3D culture systems, the differences attributed in part to the physical transition from 2D to a 3D environment causing alterations to dye resazurin uptake and conversion rates. The use of 3D culture matrices has widely been interpreted to result in "reduced" toxicity or cellular "resistance" to the chemotherapeutic agent. The results of this study show that the reduced efficiency of the drug to cells grown in the 3D environment can be accounted for by a sequential reduction of the effective concentration of the test compound and assay. This is due to absorption within the collagen gel inducing a higher uptake of both drug and assay thereby influencing the toxic impact of the drug and conversion rate of resazurin, and. The increased effective surface area of the cell exposed to the drug

  6. The Interaction of the Chemotherapeutic Drug Chlorambucil with Human Glutathione Transferase A1-1: Kinetic and Structural Analysis

    PubMed Central

    Karpusas, Michael; Axarli, Irine; Chiniadis, Lykourgos; Papakyriakou, Athanasios; Bethanis, Kostas; Scopelitou, Katholiki; Clonis, Yannis D.; Labrou, Nikolaos E.

    2013-01-01

    Glutathione transferases (GSTs) are enzymes that contribute to cellular detoxification by catalysing the nucleophilic attack of glutathione (GSH) on the electrophilic centre of a number of xenobiotic compounds, including several chemotherapeutic drugs. In the present work we investigated the interaction of the chemotherapeutic drug chlorambucil (CBL) with human GSTA1-1 (hGSTA1-1) using kinetic analysis, protein crystallography and molecular dynamics. In the presence of GSH, CBL behaves as an efficient substrate for hGSTA1-1. The rate-limiting step of the catalytic reaction between CBL and GSH is viscosity-dependent and kinetic data suggest that product release is rate-limiting. The crystal structure of the hGSTA1-1/CBL-GSH complex was solved at 2.1 Å resolution by molecular replacement. CBL is bound at the H-site attached to the thiol group of GSH, is partially ordered and exposed to the solvent, making specific interactions with the enzyme. Molecular dynamics simulations based on the crystal structure indicated high mobility of the CBL moiety and stabilization of the C-terminal helix due to the presence of the adduct. In the absence of GSH, CBL is shown to be an alkylating irreversible inhibitor for hGSTA1-1. Inactivation of the enzyme by CBL followed a biphasic pseudo-first-order saturation kinetics with approximately 1 mol of CBL per mol of dimeric enzyme being incorporated. Structural analysis suggested that the modifying residue is Cys112 which is located at the entrance of the H-site. The results are indicative of a structural communication between the subunits on the basis of mutually exclusive modification of Cys112, indicating that the two enzyme active sites are presumably coordinated. PMID:23460799

  7. Fluorescence optical imaging in anticancer drug delivery.

    PubMed

    Etrych, Tomáš; Lucas, Henrike; Janoušková, Olga; Chytil, Petr; Mueller, Thomas; Mäder, Karsten

    2016-03-28

    In the past several decades, nanosized drug delivery systems with various targeting functions and controlled drug release capabilities inside targeted tissues or cells have been intensively studied. Understanding their pharmacokinetic properties is crucial for the successful transition of this research into clinical practice. Among others, fluorescence imaging has become one of the most commonly used imaging tools in pre-clinical research. The development of increasing numbers of suitable fluorescent dyes excitable in the visible to near-infrared wavelengths of the spectrum has significantly expanded the applicability of fluorescence imaging. This paper focuses on the potential applications and limitations of non-invasive imaging techniques in the field of drug delivery, especially in anticancer therapy. Fluorescent imaging at both the cellular and systemic levels is discussed in detail. Additionally, we explore the possibility for simultaneous treatment and imaging using theranostics and combinations of different imaging techniques, e.g., fluorescence imaging with computed tomography. PMID:26892751

  8. Matrix metalloproteases: Underutilized targets for drug delivery

    PubMed Central

    Vartak, Deepali G.; Gemeinhart, Richard A.

    2013-01-01

    Pathophysiological molecules in the extracellular environment offer excellent targets that can be exploited for designing drug targeting systems. Matrix metalloproteases (MMPs) are a family of extracellular proteolytic enzymes that are characterized by their overexpression or overactivity in several pathologies. Over the last two decades, the MMP literature reveals heightened interest in the research involving MMP biology, pathology, and targeting. This review describes various strategies that have been designed to utilize MMPs for targeting therapeutic entities. Key factors that need to be considered in the successful design of such systems have been identified based on the analyses of these strategies. Development of targeted drug delivery using MMPs has been steadily pursued; however, drug delivery efforts using these targets need to be intensified and focused to realize the clinical application of the fast developing fundamental MMP research. PMID:17365270

  9. Nano carriers that enable co-delivery of chemotherapy and RNAi agents for treatment of drug-resistant cancers.

    PubMed

    Tsouris, Vasilios; Joo, Min Kyung; Kim, Sun Hwa; Kwon, Ick Chan; Won, You-Yeon

    2014-01-01

    Tumor cells exhibit drug resistant phenotypes that decrease the efficacy of chemotherapeutic treatments. The drug resistance has a genetic basis that is caused by an abnormal gene expression. There are several types of drug resistance: efflux pumps reducing the cellular concentration of the drug, alterations in membrane lipids that reduce cellular uptake, increased or altered drug targets, metabolic alteration of the drug, inhibition of apoptosis, repair of the damaged DNA, and alteration of the cell cycle checkpoints (Gottesman et al., 2002; Holohan et al., 2013). siRNA is used to silence the drug resistant phenotype and prevent this drug resistance response. Of the listed types of drug resistance, pump-type resistance (e.g., high expression of ATP-binding cassette transporter proteins such as P-glycoproteins (Pgp; also known as multi-drug resistance protein 1 or MDR1, encoded by the ATP-Binding Cassette Sub-Family B Member 1 (ABCB1) gene)) and apoptosis inhibition (e.g., expression of anti-apoptotic proteins such as Bcl-2) are the most frequently targeted for gene silencing. The co-delivery of siRNA and chemotherapeutic drugs has a synergistic effect, but many of the current projects do not control the drug release from the nanocarrier. This means that the drug payload is released before the drug resistance proteins have degraded and the drug resistance phenotype has been silenced. Current research focuses on cross-linking the carrier's polymers to prevent premature drug release, but these carriers still rely on environmental cues to release the drug payload, and the drug may be released too early. In this review, we studied the release kinetics of siRNA and chemotherapeutic drugs from a broad range of carriers. We also give examples of carriers used to co-deliver siRNA and drugs to drug-resistant tumor cells, and we examine how modifications to the carrier affect the delivery. Lastly, we give our recommendations for the future directions of the co-delivery of si

  10. Involvement of Akt and mTOR in chemotherapeutic and hormonal-based drug resistance and response to radiation in breast cancer cells

    PubMed Central

    Steelman, Linda S; Navolanic, Patrick; Chappell, William H; Abrams, Stephen L; Wong, Ellis WT; Martelli, Alberto M; Cocco, Lucio; Stivala, Franca; Libra, Massimo; Nicoletti, Ferdinando; Drobot, Lyudmyla B; Franklin, Richard A

    2011-01-01

    Elucidating the response of breast cancer cells to chemotherapeutic and hormonal based drugs and radiation is clearly important as these are common treatment approaches. Signaling cascades often involved in chemo-, hormonal- and radiation resistance are the Ras/PI3K/PTE N/Akt/mTO R, Ras/Raf/MEK/ERK and p53 pathways. In the following studies we have examined the effects of activation of the Ras/PI3K/PTE N/Akt/mTO R cascade in the response of MCF-7 breast cancer cells to chemotherapeutic- and hormonal-based drugs and radiation. Activation of Akt by introduction of conditionally-activated Akt-1 gene could result in resistance to chemotherapeutic and hormonal based drugs as well as radiation. We have determined that chemotherapeutic drugs such as doxorubicin or the hormone based drug tamoxifen, both used to treat breast cancer, resulted in the activation of the Raf/MEK/ERK pathway which is often associated with a proproliferative, anti-apoptotic response. In drug sensitive MCF-7 cells which have wild-type p53; ERK, p53 and downstream p21Cip-1 were induced upon exposure to doxorubicin. In contrast, in the drug resistant cells which expressed activated Akt-1, much lower levels of p53 and p21Cip1 were induced upon exposure to doxorubicin. These results indicate the involvement of the Ras/PI3K/PTE N/Akt/mTO R, Ras/Raf/MEK/ERK and p53 pathways in the response to chemotherapeutic and hormonal based drugs. Understanding how breast cancers respond to chemo- and hormonal-based therapies and radiation may enhance the ability to treat breast cancer more effectively. PMID:21869603

  11. A Molecular Communications Model for Drug Delivery.

    PubMed

    Femminella, Mauro; Reali, Gianluca; Vasilakos, Athanasios V

    2015-12-01

    This paper considers the scenario of a targeted drug delivery system, which consists of deploying a number of biological nanomachines close to a biological target (e.g., a tumor), able to deliver drug molecules in the diseased area. Suitably located transmitters are designed to release a continuous flow of drug molecules in the surrounding environment, where they diffuse and reach the target. These molecules are received when they chemically react with compliant receptors deployed on the receiver surface. In these conditions, if the release rate is relatively high and the drug absorption time is significant, congestion may happen, essentially at the receiver site. This phenomenon limits the drug absorption rate and makes the signal transmission ineffective, with an undesired diffusion of drug molecules elsewhere in the body. The original contribution of this paper consists of a theoretical analysis of the causes of congestion in diffusion-based molecular communications. For this purpose, it is proposed a reception model consisting of a set of pure loss queuing systems. The proposed model exhibits an excellent agreement with the results of a simulation campaign made by using the Biological and Nano-Scale communication simulator version 2 (BiNS2), a well-known simulator for molecular communications, whose reliability has been assessed through in vitro experiments. The obtained results can be used in rate control algorithms to optimally determine the optimal release rate of molecules in drug delivery applications. PMID:26529770

  12. Ultrasound-Mediated Polymeric Micelle Drug Delivery.

    PubMed

    Xia, Hesheng; Zhao, Yue; Tong, Rui

    2016-01-01

    The synthesis of multi-functional nanocarriers and the design of new stimuli-responsive means are equally important for drug delivery. Ultrasound can be used as a remote, non-invasive and controllable trigger for the stimuli-responsive release of nanocarriers. Polymeric micelles are one kind of potential drug nanocarrier. By combining ultrasound and polymeric micelles, a new modality (i.e., ultrasound-mediated polymeric micelle drug delivery) has been developed and has recently received increasing attention. A major challenge remaining in developing ultrasound-responsive polymeric micelles is the improvement of the sensitivity or responsiveness of polymeric micelles to ultrasound. This chapter reviews the recent advance in this field. In order to understand the interaction mechanism between ultrasound stimulus and polymeric micelles, ultrasound effects, such as thermal effect, cavitation effect, ultrasound sonochemistry (including ultrasonic degradation, ultrasound-initiated polymerization, ultrasonic in-situ polymerization and ultrasound site-specific degradation), as well as basic micellar knowledge are introduced. Ultrasound-mediated polymeric micelle drug delivery has been classified into two main streams based on the different interaction mechanism between ultrasound and polymeric micelles; one is based on the ultrasound-induced physical disruption of the micelle and reversible release of payload. The other is based on micellar ultrasound mechanochemical disruption and irreversible release of payload. PMID:26486348

  13. Drug Delivery Nanoparticles in Skin Cancers

    PubMed Central

    Dianzani, Chiara; Zara, Gian Paolo; Maina, Giovanni; Pettazzoni, Piergiorgio; Pizzimenti, Stefania; Rossi, Federica; Gigliotti, Casimiro Luca; Ciamporcero, Eric Stefano; Daga, Martina; Barrera, Giuseppina

    2014-01-01

    Nanotechnology involves the engineering of functional systems at nanoscale, thus being attractive for disciplines ranging from materials science to biomedicine. One of the most active research areas of the nanotechnology is nanomedicine, which applies nanotechnology to highly specific medical interventions for prevention, diagnosis, and treatment of diseases, including cancer disease. Over the past two decades, the rapid developments in nanotechnology have allowed the incorporation of multiple therapeutic, sensing, and targeting agents into nanoparticles, for detection, prevention, and treatment of cancer diseases. Nanoparticles offer many advantages as drug carrier systems since they can improve the solubility of poorly water-soluble drugs, modify pharmacokinetics, increase drug half-life by reducing immunogenicity, improve bioavailability, and diminish drug metabolism. They can also enable a tunable release of therapeutic compounds and the simultaneous delivery of two or more drugs for combination therapy. In this review, we discuss the recent advances in the use of different types of nanoparticles for systemic and topical drug delivery in the treatment of skin cancer. In particular, the progress in the treatment with nanocarriers of basal cell carcinoma, squamous cell carcinoma, and melanoma has been reported. PMID:25101298

  14. Intracarotid Delivery of Drugs: The Potential and the Pitfalls

    PubMed Central

    Joshi, Shailendra; Meyers, Phillip M.; Ornstein, Eugene

    2014-01-01

    The major efforts to selectively deliver drugs to the brain in the last decade have relied on smart molecular techniques to penetrate the blood brain barrier while intraarterial drug delivery has drawn relatively little attention. In the last decade there have been rapid advances in endovascular techniques. Modern endovascular procedures can permit highly targeted drug delivery by intracarotid route. Intracarotid drug delivery can be the primary route of drug delivery or it could be used to facilitate the delivery of smart-neuropharmaceuticals. There have been few attempts to systematically understand the kinetics of intracarotid drugs. Anecdotal data suggests that intracarotid drug delivery is effective in the treatment of cerebral vasospasm, thromboembolic strokes, and neoplasms. Neuroanesthesiologists are frequently involved in the care of such high-risk patients. Therefore, it is necessary to understand the applications of intracarotid drug delivery and the unusual kinetics of intracarotid drugs. PMID:18719453

  15. A novel in vitro three-dimensional retinoblastoma model for evaluating chemotherapeutic drugs

    PubMed Central

    Mitra, Moutushy; Mohanty, Chandana; Harilal, Anju; Maheswari, Uma K.; Sahoo, Sanjeeb Kumar

    2012-01-01

    Purpose Novel strategies are being applied for creating better in vitro models that simulate in vivo conditions for testing the efficacy of anticancer drugs. In the present study we developed surface-engineered, large and porous, biodegradable, polymeric microparticles as a scaffold for three dimensional (3-D) growth of a Y79 retinoblastoma (RB) cell line. We evaluated the effect of three anticancer drugs in naïve and nanoparticle-loaded forms on a 3-D versus a two-dimensional (2-D) model. We also studied the influence of microparticles on extracellular matrix (ECM) synthesis and whole genome miRNA-gene expression profiling to identify 3D-responsive genes that are implicated in oncogenesis in RB cells. Methods Poly(D,L)-lactide-co-glycolide (PLGA) microparticles were prepared by the solvent evaporation method. RB cell line Y79 was grown alone or with PLGA–gelatin microparticles. Antiproliferative activity, drug diffusion, and cellular uptake were studied by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a yellow tetrazole (MTT) assay, fluorescent microscope, and flow cytometry. Extra cellular matrix (ECM) synthesis was observed by collagenase assay and whole genome miRNA-microarray profiling by using an Agilent chip. Results With optimized composition of microparticles and cell culture conditions, an eightfold increase from the seeding density was achieved in 5 days of culture. The antiproliferative effect of the drugs in the 3-D model was significantly lower than in the 2-D suspension, which was evident from the 4.5 to 21.8 fold differences in their IC50 values. Using doxorubicin, the flow cytometry data demonstrated a 4.4 fold lower drug accumulation in the cells grown in the 3-D model at 4 h. The collagen content of the cells grown in the 3-D model was 2.3 fold greater than that of the cells grown in the 2-D model, suggesting greater synthesis of the extracellular matrix in the 3-D model as the extracellular matrix acted as a barrier to drug

  16. Methionine depletion with recombinant methioninase: In vitro and in vivo efficacy against neuroblastoma and its synergism with chemotherapeutic drugs

    PubMed Central

    Hu, Jian; Cheung, Nai-Kong V.

    2009-01-01

    Methionine starvation can modulate gene methylation, cell cycle transition, and pathways related to survival following DNA damage. Methionine depletion by recombinant methioninase (rMETase) may have in vitro and in vivo efficacy against neuroblastoma (NB), especially when combined with chemotherapeutic drugs. rMETase from Pseudomonas Putida was produced in E. Coli and purified by ion-exchange chromatography. rMETase alone inhibited the proliferation of 15/15 NB cell lines in vitro. Among these 15 cell lines, only 66N demonstrated rMETase-induced apoptosis. rMETase alone suppressed LAN-1 and NMB-7 xenografts (p<0.01) and no toxicities were noted other than reversible weight loss. In vitro efficacy experiments combining rMETase and chemotherapeutic agents were carried out using SK-N-LD and SK-N-BE(1)N established at diagnosis, as well as LAN-1, SK-N-BE(2)C, and NMB-7 established at relapse. Microtubule depolymerization agents including vincristine, vinorelbine, vinblatine, and mebendazole showed synergism when tested in combination with rMETase in all 5 cell lines. Among DNA damaging agents, synergy with rMETase was observed only in cell lines established at diagnosis, and not at relapse. Cell cycle analysis showed that rMETase arrested G2 phase, and not M phase. In vivo efficacy experiments using LAN-1 and NMB-7 xenografts showed that rMETase rendered vincristine more effective than vincristine alone in tumor growth suppression (p<0.001). In conclusion, methionine depletion inhibited NB proliferation and arrested tumor cells at G2 phase. rMETase synergized with microtubule depolymerization agents. Moreover, synergism between rMETase and DNA damaging agents was dependent on whether cell lines were established at diagnosis or at relapse. PMID:19089915

  17. Drug delivery to the lymphatic system: importance in future cancer diagnosis and therapies

    PubMed Central

    Xie, Yumei; Bagby, Taryn R; Cohen, MS

    2011-01-01

    Cancer is the second leading cause of death in the US. Currently, protocols for cancer treatment include surgery to remove diseased and suspect tissues, focused radiation, systemic chemotherapy, immunotherapy and their combinations. With conventional chemotherapy, it is almost impossible to deliver anticancer drugs specifically to the tumor cells without damaging healthy organs or tissues. Over the past several decades, efforts have been made to improve drug delivery technologies that target anticancer drugs specifically to tumor cells. It has been known for over four decades that the lymphatics are the first site of metastasis for most solid cancers; however, few efforts have been made to localize chemotherapies to lymphatic tissues. Trials of several systemic targeted drug delivery systems based on nanoparticles containing chemotherapeutic agents (e.g., liposomal doxorubicin) have shown similar antitumor activity but better patient tolerance compared with conventional formulations. Animal studies have demonstrated that nanoparticles made of natural or synthetic polymers and liposomal carriers have higher accumulation in the lymph nodes and surrounding lymphatics compared to conventional intravenous therapies. This combination has the potential to both reduce nonspecific organ toxicities and increase the chemotherapeutic dose to the most likely sites of locoregional cancer metastasis. PMID:19563270

  18. Inhalation drug delivery devices: technology update

    PubMed Central

    Ibrahim, Mariam; Verma, Rahul; Garcia-Contreras, Lucila

    2015-01-01

    The pulmonary route of administration has proven to be effective in local and systemic delivery of miscellaneous drugs and biopharmaceuticals to treat pulmonary and non-pulmonary diseases. A successful pulmonary administration requires a harmonic interaction between the drug formulation, the inhaler device, and the patient. However, the biggest single problem that accounts for the lack of desired effect or adverse outcomes is the incorrect use of the device due to lack of training in how to use the device or how to coordinate actuation and aerosol inhalation. This review summarizes the structural and mechanical features of aerosol delivery devices with respect to mechanisms of aerosol generation, their use with different formulations, and their advantages and limitations. A technological update of the current state-of-the-art designs proposed to overcome current challenges of existing devices is also provided. PMID:25709510

  19. Polysaccharide-Based Micelles for Drug Delivery

    PubMed Central

    Zhang, Nan; Wardwell, Patricia R.; Bader, Rebecca A.

    2013-01-01

    Delivery of hydrophobic molecules and proteins has been an issue due to poor bioavailability following administration. Thus, micelle carrier systems are being investigated to improve drug solubility and stability. Due to problems with toxicity and immunogenicity, natural polysaccharides are being explored as substitutes for synthetic polymers in the development of new micelle systems. By grafting hydrophobic moieties to the polysaccharide backbone, self-assembled micelles can be readily formed in aqueous solution. Many polysaccharides also possess inherent bioactivity that can facilitate mucoadhesion, enhanced targeting of specific tissues, and a reduction in the inflammatory response. Furthermore, the hydrophilic nature of some polysaccharides can be exploited to enhance circulatory stability. This review will highlight the advantages of polysaccharide use in the development of drug delivery systems and will provide an overview of the polysaccharide-based micelles that have been developed to date. PMID:24300453

  20. Caged Protein Nanoparticles for Drug Delivery

    PubMed Central

    Molino, Nicholas M.; Wang, Szu-Wen

    2014-01-01

    Caged protein nanoparticles possess many desirable features for drug delivery, such as ideal sizes for endocytosis, non-toxic biodegradability, and the ability to functionalize at three distinct interfaces (external, internal, and inter-subunit) using the tools of protein engineering. Researchers have harnessed these attributes by covalently and non-covalently loading therapeutic molecules through mechanisms that facilitate release within specific microenvironments. Effective delivery depends on several factors, including specific targeting, cell uptake, release kinetics, and systemic clearance. The innate ability of the immune system to recognize and respond to proteins has recently been exploited to deliver therapeutic compounds with these platforms for immunomodulation. The diversity of drugs, loading/release mechanisms, therapeutic targets, and therapeutic efficacy are discussed in this review. PMID:24832078

  1. Diatomite silica nanoparticles for drug delivery

    NASA Astrophysics Data System (ADS)

    Ruggiero, Immacolata; Terracciano, Monica; Martucci, Nicola M.; De Stefano, Luca; Migliaccio, Nunzia; Tatè, Rosarita; Rendina, Ivo; Arcari, Paolo; Lamberti, Annalisa; Rea, Ilaria

    2014-07-01

    Diatomite is a natural fossil material of sedimentary origin, constituted by fragments of diatom siliceous skeletons. In this preliminary work, the properties of diatomite nanoparticles as potential system for the delivery of drugs in cancer cells were exploited. A purification procedure, based on thermal treatments in strong acid solutions, was used to remove inorganic and organic impurities from diatomite and to make them a safe material for medical applications. The micrometric diatomite powder was reduced in nanoparticles by mechanical crushing, sonication, and filtering. Morphological analysis performed by dynamic light scattering and transmission electron microscopy reveals a particles size included between 100 and 300 nm. Diatomite nanoparticles were functionalized by 3-aminopropyltriethoxysilane and labeled by tetramethylrhodamine isothiocyanate. Different concentrations of chemically modified nanoparticles were incubated with cancer cells and confocal microscopy was performed. Imaging analysis showed an efficient cellular uptake and homogeneous distribution of nanoparticles in cytoplasm and nucleus, thus suggesting their potentiality as nanocarriers for drug delivery.

  2. Nanotechnology Approaches for Ocular Drug Delivery

    PubMed Central

    Xu, Qingguo; Kambhampati, Siva P.; Kannan, Rangaramanujam M.

    2013-01-01

    Blindness is a major health concern worldwide that has a powerful impact on afflicted individuals and their families, and is associated with enormous socio-economical consequences. The Middle East is heavily impacted by blindness, and the problem there is augmented by an increasing incidence of diabetes in the population. An appropriate drug/gene delivery system that can sustain and deliver therapeutics to the target tissues and cells is a key need for ocular therapies. The application of nanotechnology in medicine is undergoing rapid progress, and the recent developments in nanomedicine-based therapeutic approaches may bring significant benefits to address the leading causes of blindness associated with cataract, glaucoma, diabetic retinopathy and retinal degeneration. In this brief review, we highlight some promising nanomedicine-based therapeutic approaches for drug and gene delivery to the anterior and posterior segments. PMID:23580849

  3. Zwitterionic drug nanocarriers: a biomimetic strategy for drug delivery.

    PubMed

    Jin, Qiao; Chen, Yangjun; Wang, Yin; Ji, Jian

    2014-12-01

    Nanomaterials self-assembled from amphiphilic functional copolymers have emerged as safe and efficient nanocarriers for delivery of therapeutics. Surface engineering of the nanocarriers is extremely important for the design of drug delivery systems. Bioinspired zwitterions are considered as novel nonfouling materials to construct biocompatible and bioinert nanocarriers. As an alternative to poly(ethylene glycol) (PEG), zwitterions exhibit some unique properties that PEG do not have. In this review, we highlight recent progress of the design of drug nanocarriers using a zwitterionic strategy. The possible mechanism of stealth properties of zwitterions was proposed. The advantages of zwitterionic drug nanocarriers deriving from phosphorylcholine (PC), carboxybetaine (CB), and sulfobetaine (SB) are also discussed. PMID:25092584

  4. Microneedle Coating Techniques for Transdermal Drug Delivery.

    PubMed

    Haj-Ahmad, Rita; Khan, Hashim; Arshad, Muhammad Sohail; Rasekh, Manoochehr; Hussain, Amjad; Walsh, Susannah; Li, Xiang; Chang, Ming-Wei; Ahmad, Zeeshan

    2015-01-01

    Drug administration via the transdermal route is an evolving field that provides an alternative to oral and parenteral routes of therapy. Several microneedle (MN) based approaches have been developed. Among these, coated MNs (typically where drug is deposited on MN tips) are a minimally invasive method to deliver drugs and vaccines through the skin. In this review, we describe several processes to coat MNs. These include dip coating, gas jet drying, spray coating, electrohydrodynamic atomisation (EHDA) based processes and piezoelectric inkjet printing. Examples of process mechanisms, conditions and tested formulations are provided. As these processes are independent techniques, modifications to facilitate MN coatings are elucidated. In summary, the outcomes and potential value for each technique provides opportunities to overcome formulation or dosage form limitations. While there are significant developments in solid degradable MNs, coated MNs (through the various techniques described) have potential to be utilized in personalized drug delivery via controlled deposition onto MN templates. PMID:26556364

  5. Intratumoral Drug Delivery with Nanoparticulate Carriers

    PubMed Central

    Holback, Hillary

    2011-01-01

    Stiff extracellular matrix, elevated interstitial fluid pressure, and the affinity for the tumor cells in the peripheral region of a solid tumor mass have long been recognized as significant barriers to diffusion of small-molecular-weight drugs and antibodies. However, their impacts on nanoparticle-based drug delivery have begun to receive due attention only recently. This article reviews biological features of many solid tumors that influence transport of drugs and nanoparticles and properties of nanoparticles relevant to their intratumoral transport, studied in various tumor models. We also discuss several experimental approaches employed to date for enhancement of intratumoral nanoparticle penetration. The impact of nanoparticle distribution on the effectiveness of chemotherapy remains to be investigated and should be considered in the design of new nanoparticulate drug carriers. PMID:21213021

  6. Nanogel Carrier Design for Targeted Drug Delivery

    PubMed Central

    Eckmann, D. M.; Composto, R. J.; Tsourkas, A.; Muzykantov, V. R.

    2014-01-01

    Polymer-based nanogel formulations offer features attractive for drug delivery, including ease of synthesis, controllable swelling and viscoelasticity as well as drug loading and release characteristics, passive and active targeting, and the ability to formulate nanogel carriers that can respond to biological stimuli. These unique features and low toxicity make the nanogels a favorable option for vascular drug targeting. In this review, we address key chemical and biological aspects of nanogel drug carrier design. In particular, we highlight published studies of nanogel design, descriptions of nanogel functional characteristics and their behavior in biological models. These studies form a compendium of information that supports the scientific and clinical rationale for development of this carrier for targeted therapeutic interventions. PMID:25485112

  7. Injected nanocrystals for targeted drug delivery

    PubMed Central

    Lu, Yi; Li, Ye; Wu, Wei

    2016-01-01

    Nanocrystals are pure drug crystals with sizes in the nanometer range. Due to the advantages of high drug loading, platform stability, and ease of scaling-up, nanocrystals have been widely used to deliver poorly water-soluble drugs. Nanocrystals in the blood stream can be recognized and sequestered as exogenous materials by mononuclear phagocytic system (MPS) cells, leading to passive accumulation in MPS-rich organs, such as liver, spleen and lung. Particle size, morphology and surface modification affect the biodistribution of nanocrystals. Ligand conjugation and stimuli-responsive polymers can also be used to target nanocrystals to specific pathogenic sites. In this review, the progress on injected nanocrystals for targeted drug delivery is discussed following a brief introduction to nanocrystal preparation methods, i.e., top-down and bottom-up technologies. PMID:27006893

  8. Microneedle Coating Techniques for Transdermal Drug Delivery

    PubMed Central

    Haj-Ahmad, Rita; Khan, Hashim; Arshad, Muhammad Sohail; Rasekh, Manoochehr; Hussain, Amjad; Walsh, Susannah; Li, Xiang; Chang, Ming-Wei; Ahmad, Zeeshan

    2015-01-01

    Drug administration via the transdermal route is an evolving field that provides an alternative to oral and parenteral routes of therapy. Several microneedle (MN) based approaches have been developed. Among these, coated MNs (typically where drug is deposited on MN tips) are a minimally invasive method to deliver drugs and vaccines through the skin. In this review, we describe several processes to coat MNs. These include dip coating, gas jet drying, spray coating, electrohydrodynamic atomisation (EHDA) based processes and piezoelectric inkjet printing. Examples of process mechanisms, conditions and tested formulations are provided. As these processes are independent techniques, modifications to facilitate MN coatings are elucidated. In summary, the outcomes and potential value for each technique provides opportunities to overcome formulation or dosage form limitations. While there are significant developments in solid degradable MNs, coated MNs (through the various techniques described) have potential to be utilized in personalized drug delivery via controlled deposition onto MN templates. PMID:26556364

  9. Advanced drug delivery approaches against periodontitis.

    PubMed

    Joshi, Deeksha; Garg, Tarun; Goyal, Amit K; Rath, Goutam

    2016-01-01

    Periodontitis is an inflammatory disease of gums involving the degeneration of periodontal ligaments, creation of periodontal pocket and resorption of alveolar bone, resulting in the disruption of the support structure of teeth. According to WHO, 10-15% of the global population suffers from severe periodontitis. The disease results from the growth of a diverse microflora (especially anaerobes) in the pockets and release of toxins, enzymes and stimulation of body's immune response. Various local or systemic approaches were used for an effective treatment of periodontitis. Currently, controlled local drug delivery approach is more favorable as compared to systemic approach because it mainly focuses on improving the therapeutic outcomes by achieving factors like site-specific delivery, low dose requirement, bypass of first-pass metabolism, reduction in gastrointestinal side effects and decrease in dosing frequency. Overall it provides a safe and effective mode of treatment, which enhances patient compliance. Complete eradication of the organisms from the sites was not achieved by using various surgical and mechanical treatments. So a number of polymer-based delivery systems like fibers, films, chips, strips, microparticles, nanoparticles and nanofibers made from a variety of natural and synthetic materials have been successfully tested to deliver a variety of drugs. These systems are biocompatible and biodegradable, completely fill the pockets, and have strong retention on the target site due to excellent mucoadhesion properties. The review summarizes various available and recently developing targeted delivery devices for the treatment of periodontitis. PMID:25005586

  10. A model of axonal transport drug delivery

    NASA Astrophysics Data System (ADS)

    Kuznetsov, Andrey

    2012-04-01

    In this paper a model of targeted drug delivery by means of active (motor-driven) axonal transport is developed. The model is motivated by recent experimental research by Filler et al. (A.G. Filler, G.T. Whiteside, M. Bacon, M. Frederickson, F.A. Howe, M.D. Rabinowitz, A.J. Sokoloff, T.W. Deacon, C. Abell, R. Munglani, J.R. Griffiths, B.A. Bell, A.M.L. Lever, Tri-partite complex for axonal transport drug delivery achieves pharmacological effect, Bmc Neuroscience 11 (2010) 8) that reported synthesis and pharmacological efficiency tests of a tri-partite complex designed for axonal transport drug delivery. The developed model accounts for two populations of pharmaceutical agent complexes (PACs): PACs that are transported retrogradely by dynein motors and PACs that are accumulated in the axon at the Nodes of Ranvier. The transitions between these two populations of PACs are described by first-order reactions. An analytical solution of the coupled system of transient equations describing conservations of these two populations of PACs is obtained by using Laplace transform. Numerical results for various combinations of parameter values are presented and their physical significance is discussed.

  11. Ultrasound-mediated nail drug delivery system.

    PubMed

    Abadi, Danielle; Zderic, Vesna

    2011-12-01

    A novel ultrasound-mediated drug delivery system has been developed for treatment of a nail fungal disorder (onychomycosis) by improving delivery to the nail bed using ultrasound to increase the permeability of the nail. The slip-in device consists of ultrasound transducers and drug delivery compartments above each toenail. The device is connected to a computer, where a software interface allows users to select their preferred course of treatment. In in vitro testing, canine nails were exposed to 3 energy levels (acoustic power of 1.2 W and exposure durations of 30, 60, and 120 seconds). A stereo -microscope was used to determine how much of a drug-mimicking compound was delivered through the nail layers by measuring brightness on the cross section of each nail tested at each condition, where brightness level decreases coincide with increases in permeability. Each of the 3 energy levels tested showed statistical significance when compared to the control (P < .05) with a permeability factor of 1.3 after 30 seconds of exposure, 1.3 after 60 seconds, and 1.5 after 120 seconds, where a permeability factor of 1 shows no increase in permeability. Current treatments for onychomycosis include systemic, topical, and surgical. Even when used all together, these treatments typically take a long time to result in nail healing, thus making this ultrasound-mediated device a promising alternative. PMID:22124008

  12. Approaches for drug delivery with intracortical probes.

    PubMed

    Spieth, Sven; Schumacher, Axel; Trenkle, Fabian; Brett, Olivia; Seidl, Karsten; Herwik, Stanislav; Kisban, Sebastian; Ruther, Patrick; Paul, Oliver; Aarts, Arno A A; Neves, Hercules P; Rich, P Dylan; Theobald, David E; Holtzman, Tahl; Dalley, Jeffrey W; Verhoef, Bram-Ernst; Janssen, Peter; Zengerle, Roland

    2014-08-01

    Intracortical microprobes allow the precise monitoring of electrical and chemical signaling and are widely used in neuroscience. Microelectromechanical system (MEMS) technologies have greatly enhanced the integration of multifunctional probes by facilitating the combination of multiple recording electrodes and drug delivery channels in a single probe. Depending on the neuroscientific application, various assembly strategies are required in addition to the microprobe fabrication itself. This paper summarizes recent advances in the fabrication and assembly of micromachined silicon probes for drug delivery achieved within the EU-funded research project NeuroProbes. The described fabrication process combines a two-wafer silicon bonding process with deep reactive ion etching, wafer grinding, and thin film patterning and offers a maximum in design flexibility. By applying this process, three general comb-like microprobe designs featuring up to four 8-mm-long shafts, cross sections from 150×200 to 250×250 µm², and different electrode and fluidic channel configurations are realized. Furthermore, we discuss the development and application of different probe assemblies for acute, semichronic, and chronic applications, including comb and array assemblies, floating microprobe arrays, as well as the complete drug delivery system NeuroMedicator for small animal research. PMID:24101367

  13. Controlled Ocular Drug Delivery with Nanomicelles

    PubMed Central

    Vaishya, Ravi D.; Khurana, Varun; Patel, Sulabh; Mitra, Ashim K.

    2014-01-01

    Many vision threatening ocular diseases such as age-related macular degeneration (AMD), diabetic retinopathy, glaucoma, and proliferative vitreoretinopathy may result in blindness. Ocular drug delivery specifically to the intraocular tissues remains a challenging task due to the presence of various physiological barriers. Nonetheless, recent advancements in the field of nanomicelle based novel drug delivery system could fulfil these unmet needs. Nanomicelles consists of amphiphilic molecules that self-assemble in aqueous media to form organized supramolecular structures. Micelles can be prepared in various sizes (10 to 1000nm) and shapes depending on the molecular weights of the core and corona forming blocks. Nanomicelles have been an attractive carriers for their potential to solubilize hydrophobic molecules in aqueous solution. In addition, small size in nanometer range and highly modifiable surface properties have been reported to be advantageous in ocular drug delivery. In the present review various factors influencing rationale design of nanomicelles formulation and disposition are discussed along with case studies. Despite the progress in the field, influence of various properties of nanomicelles such as size, shape, surface charge, rigidity of structure on ocular disposition need to be studied in further details to develop an efficient nanocarrier system. PMID:24888969

  14. Protein and Peptide Drug Delivery: Oral Approaches

    PubMed Central

    Shaji, Jessy; Patole, V.

    2008-01-01

    Till recent, injections remained the most common means for administering therapeutic proteins and peptides because of their poor oral bioavailability. However, oral route would be preferred to any other route because of its high levels of patient acceptance and long term compliance, which increases the therapeutic value of the drug. Designing and formulating a polypeptide drug delivery through the gastro intestinal tract has been a persistent challenge because of their unfavorable physicochemical properties, which includes enzymatic degradation, poor membrane permeability and large molecular size. The main challenge is to improve the oral bioavailability from less than 1% to at least 30-50%. Consequently, efforts have intensified over the past few decades, where every oral dosage form used for the conventional small molecule drugs has been used to explore oral protein and peptide delivery. Various strategies currently under investigation include chemical modification, formulation vehicles and use of enzyme inhibitors, absorption enhancers and mucoadhesive polymers. This review summarizes different pharmaceutical approaches which overcome various physiological barriers that help to improve oral bioavailability that ultimately achieve formulation goals for oral delivery. PMID:20046732

  15. Stemness and chemotherapeutic drug resistance induced by EIF5A2 overexpression in esophageal squamous cell carcinoma

    PubMed Central

    Yang, Hong; Li, Xiao-dong; Zhou, Ying; Ban, Xiaojiao; Zeng, Ting-ting; Li, Lei; Zhang, Bao-zhu; Yun, Jingping; Xie, Dan; Guan, Xin-Yuan; Li, Yan

    2015-01-01

    Esophageal squamous cell carcinoma (ESCC) is one of the most lethal malignancies of the digestive tract in East Asian countries. Multimodal therapies, including adjuvant chemotherapy and neo-adjuvant chemotherapy, have become more often used for patients with advanced ESCC. However, the chemotherapy effect is often limited by patients' drug resistance. This study demonstrated that EIF5A2 (eukaryotic translation initiation factor 5A2) overexpression induced stemness and chemoresistance in ESCC cells. We showed that EIF5A2 overexpression in ESCC cells resulted in increased chemoresistance to 5-fluorouracil (5-FU), docetaxel and taxol. In contrast, shRNAs suppressing eIF5A2 increased tumor sensitivity to these chemotherapeutic drugs. In addition, EIF5A2 overexpression was correlated with a poorer overall survival in patients with ESCC who underwent taxane-based chemotherapy after esophagectomy (P < 0.05). Based on these results, we suggest that EIF5A2 could be a predictive biomarker for selecting appropriate chemo-treatment for ESCC patients and EIF5A2 inhibitors might be considered as combination therapy to enhance chemosensitivity in patients with ESCC. PMID:26317793

  16. Develop a novel superparamagnetic nano-carrier for drug delivery to brain glioma.

    PubMed

    Zhao, Ming; Li, Anmin; Chang, Jin; Fu, Xiangping; Zhang, Zhiwen; Yan, Runmin; Wang, Hanjie; Liang, Shuli

    2013-01-01

    Magnetic drug carrier has been employed in drug delivery for over 30 years. Modern nanotechnology has improved its efficiency dramatically by decreasing its diameter into nano-scale. It may help chemotherapeutic agents penetrate BBB and raise local drug concentration in brain, which is the ideal model for glioma treatment. In our study, magnetic carrier was fabricated with octadecyl quaternized caroxymethyl chitosan (OQCMC), hydrophobic Fe₃O₄ ferrofluid and cholesterol, which showed a uniform diameter of 20 nm under transmission electronic microscopy and superparamagnetic character in vibration sample magnetical measurement system. To investigate the efficacy of drug delivery, paclitaxel was used as loaded drug and analyzed by the HPLC. Results showed that magnetic carrier released drugs for more than 20 d in vitro and maintain the drug concentration above 0.4 μg/g for 16 h in rat brain after magnetic targeting. Drug concentration increased by 1-3 folds when delivered by carrier without magnetic targeting, and by 3-15 folds after magnetic targeting. Cellular study revealed that the magnetic carrier was clearly localized in the targeted cortex neural cells and U251-MG cell lines. These results showed that this magnetic carrier is capable of maintaining high drug concentration in magnetically targeted area and carrying drugs or genes into cells, which is potentially promising for local chemotherapy to brain tumors. PMID:23701032

  17. iRGD-coupled responsive fluorescent nanogel for targeted drug delivery.

    PubMed

    Su, Shishuai; Wang, Hai; Liu, Xiaoguang; Wu, Yan; Nie, Guangjun

    2013-04-01

    In this investigation, we have designed and synthesized a multifunctional nanogel for anti-tumor drug delivery. Thermo- and pH-responsive poly (N-isopropyl acrylamide-co-acrylic acid) nanogels (NGs) were synthesized by free radical precipitation polymerization. Positive charged chemotherapeutic drug doxorubicin (DOX) was introduced into the negatively charged swollen NGs by electrostatic adsorption at pH 7.4. Fluorescent bovine serum albumin (BSA) encapsulated gold nanoclusters (AuNCs) were conjugated onto the surface of NGs, followed by functionalization of tumor targeting peptide iRGD onto the BSA for tumor targeting. Interestingly, the DOX-encapsulated iRGD-decorated NGs maintain both thermo- and pH-responsive properties, which are favorable for achieving a controlled drug release in tumor tissues. Stable red fluorescent emission, derived from AuNCs, was used to detect and track the NGs in vitro. As expected, the iRGD motif mediated specific targeting to tumor and endothelial cells and enhanced cellular uptake of the NGs, as demonstrated by flow cytometry and confocal microscopy assays. In vitro cytotoxicity studies proved that the presence of iRGD enhanced the cytotoxic efficiency of DOX to the targeted cells. All together, our current study indicates that the NGs drug-carriers can deliver chemotherapeutic drug specifically to the tumor and endothelial cells with enhanced anti-tumor efficacy and controlled drug release. PMID:23410678

  18. Drug Delivery to the Ischemic Brain

    PubMed Central

    Thompson, Brandon J.; Ronaldson, Patrick T.

    2014-01-01

    Cerebral ischemia occurs when blood flow to the brain is insufficient to meet metabolic demand. This can result from cerebral artery occlusion that interrupts blood flow, limits CNS supply of oxygen and glucose, and causes an infarction/ischemic stroke. Ischemia initiates a cascade of molecular events inneurons and cerebrovascular endothelial cells including energy depletion, dissipation of ion gradients, calcium overload, excitotoxicity, oxidative stress, and accumulation of ions and fluid. Blood-brain barrier (BBB) disruption is associated with cerebral ischemia and leads to vasogenic edema, a primary cause of stroke-associated mortality. To date, only a single drug has received US Food and Drug Administration (FDA) approval for acute ischemic stroke treatment, recombinant tissue plasminogen activator (rt-PA). While rt-PA therapy restores perfusion to ischemic brain, considerable tissue damage occurs when cerebral blood flow is re-established. Therefore, there is a critical need for novel therapeutic approaches that can “rescue” salvageable brain tissue and/or protect BBB integrity during ischemic stroke. One class of drugs that may enable neural cell rescue following cerebral ischemia/reperfusion injury is the HMG-CoA reductase inhibitors (i.e., statins). Understanding potential CNS drug delivery pathways for statins is critical to their utility in ischemic stroke. Here, we review molecular pathways associated with cerebral ischemia and novel approaches for delivering drugs to treat ischemic disease. Specifically, we discuss utility of endogenous BBB drug uptake transporters such as organic anion transporting polypeptides (OATPs/Oatps) and nanotechnology-based carriers for optimization of CNS drug delivery. Overall, this chapter highlights state-of-the-art technologies that may improve pharmacotherapy of cerebral ischemia. PMID:25307217

  19. Protein-Based Nanomedicine Platforms for Drug Delivery

    SciTech Connect

    Ma Ham, Aihui; Tang, Zhiwen; Wu, Hong; Wang, Jun; Lin, Yuehe

    2009-08-03

    Drug delivery systems have been developed for many years, however some limitations still hurdle the pace of going to clinical phase, for example, poor biodistribution, drug molecule cytotoxicity, tissue damage, quick clearance from the circulation system, solubility and stability of drug molecules. To overcome the limitations of drug delivery, biomaterials have to be developed and applied to drug delivery to protect the drug molecules and to enhance the drug’s efficacy. Protein-based nanomedicine platforms for drug delivery are platforms comprised of naturally self-assembled protein subunits of the same protein or a combination of proteins making up a complete system. They are ideal for drug delivery platforms due to their biocompatibility and biodegradability coupled with low toxicity. A variety of proteins have been used and characterized for drug delivery systems including the ferritin/apoferritin protein cage, plant derived viral capsids, the small Heat shock protein (sHsp) cage, albumin, soy and whey protein, collagen, and gelatin. There are many different types and shapes that have been prepared to deliver drug molecules using protein-based platforms including the various protein cages, microspheres, nanoparticles, hydrogels, films, minirods and minipellets. There are over 30 therapeutic compounds that have been investigated with protein-based drug delivery platforms for the potential treatment of various cancers, infectious diseases, chronic diseases, autoimmune diseases. In protein-based drug delivery platforms, protein cage is the most newly developed biomaterials for drug delivery and therapeutic applications. Their uniform sizes, multifunctions, and biodegradability push them to the frontier for drug delivery. In this review, the recent strategic development of drug delivery has been discussed with a special emphasis upon the polymer based, especially protein-based nanomedicine platforms for drug delivery. The advantages and disadvantages are also

  20. Silk Electrogel Based Gastroretentive Drug Delivery System

    NASA Astrophysics Data System (ADS)

    Wang, Qianrui

    Gastric cancer has become a global pandemic and there is imperative to develop efficient therapies. Oral dosing strategy is the preferred route to deliver drugs for treating the disease. Recent studies suggested silk electro hydrogel, which is pH sensitive and reversible, has potential as a vehicle to deliver the drug in the stomach environment. The aim of this study is to establish in vitro electrogelation e-gel based silk gel as a gastroretentive drug delivery system. We successfully extended the duration of silk e-gel in artificial gastric juice by mixing silk solution with glycerol at different ratios before the electrogelation. Structural analysis indicated the extended duration was due to the change of beta sheet content. The glycerol mixed silk e-gel had good doxorubicin loading capability and could release doxorubicin in a sustained-release profile. Doxorubicin loaded silk e-gels were applied to human gastric cancer cells. Significant cell viability decrease was observed. We believe that with further characterization as well as functional analysis, the silk e-gel system has the potential to become an effective vehicle for gastric drug delivery applications.

  1. Microemulsions based transdermal drug delivery systems.

    PubMed

    Vadlamudi, Harini C; Narendran, Hyndavi; Nagaswaram, Tejeswari; Yaga, Gowri; Thanniru, Jyotsna; Yalavarthi, Prasanna R

    2014-01-01

    Since the discovery of microemulsions by Jack H Schulman, there has been huge progress made in applying microemulsion systems in plethora of research and industrial process. Microemulsions are optically isotropic systems consisting of water, oil and amphiphile. These systems are beneficial due to their thermodynamic stability, optical clarity, ease of preparation, higher diffusion and absorption rates. Moreover, it has been reported that the ingredients of microemulsion can effectively overcome the diffusion barrier and penetrate through the stratum corneum of the skin. Hence it becomes promising for both transdermal and dermal drug delivery. However, low viscosity of microemulsion restrains its applicability in pharmaceutical industry. To overcome the above drawback, the low viscous microemulsions were added to viscous gel bases to potentiate its applications as topical drug delivery systems so that various drug related toxic effects and erratic drug absorption can be avoided. The present review deals with the microemulsions, various techniques involved in the development of organic nanoparticles. The review emphasized on microemulsion based systems such as hydrogels and organogels. The physicochemical characteristics, mechanical properties, rheological and stability principles involved in microemulsion based viscous gels were also explored. PMID:25466399

  2. Ocular drug delivery of progesterone using nanoparticles.

    PubMed

    Li, V H; Wood, R W; Kreuter, J; Harmia, T; Robinson, J R

    1986-01-01

    The objective of this study was to evaluate ocular delivery of a lipid-soluble drug, [3H]progesterone, using nanoparticles. Polybutylcyanoacrylate nanoparticles loaded with [3H]progesterone were prepared by an emulsion polymerization technique using a hydrophilic continuous phase. The resulting nanoparticle suspension contained 2 x 10(-5) M progesterone. It was found that, at equilibrium, 99 per cent of the progesterone resided in the nanoparticles and the remainder in the aqueous phase indicating an excellent encapsulation efficiency. In addition, an appropriate control solution of progesterone was prepared, which did not contain polybutylcyanoacrylate. Concentrations of [3H]progesterone in various ocular tissues of the albino rabbit were monitored at various times following topical administration of either the nanoparticle suspension or the control solutions. Comparison of the concentration-time profiles indicates that tissue concentration of progesterone following topical administration of nanoparticles is generally four to five times less than that obtained with control solutions. This decreased concentration suggests that, due to the high affinity of progesterone for the nanoparticles, the drug is being made less available for absorption during its residence time in the precorneal area. The utility of nanoparticles as an ocular drug delivery system may depend on optimizing lipophilic-hydrophilic properties of the polymer-drug system, in addition to increasing retention efficiency in the precorneal pocket. PMID:3508187

  3. Designing polymeric microparticulate drug delivery system for hydrophobic drug quercetin

    PubMed Central

    Hazra, Moumita; Dasgupta Mandal, Dalia; Mandal, Tamal; Bhuniya, Saikat; Ghosh, Mallika

    2015-01-01

    The aim of this study was to investigate pharmaceutical potentialities of a polymeric microparticulate drug delivery system for modulating the drug profile of poorly water-soluble quercetin. In this research work two cost effective polymers sodium alginate and chitosan were used for entrapping the model drug quercetin through ionic cross linking method. In vitro drug release, swelling index, drug entrapment efficiency, Fourier Transforms Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Differential Scanning Calorimetric (DSC) studies were also done for physicochemical characterization of the formulations. Swelling index and drug release study were done at a pH of 1.2, 6.8 and 7.4 to evaluate the GI mimetic action which entails that the swelling and release of the all the Formulation1 (F1), Formulation2 (F2) and Formulation3 (F3) at pH 1.2 were minimal confirming the prevention of drug release in the acidic environment of stomach. Comparatively more sustained release was seen from the formulations F2 & F3 at pH 6.8 and pH 7.4 after 7 h of drug release profiling. Drug entrapment efficiency of the formulations shows in F1 (D:C:A = 2:5:30) was approximately 70% whereas the increase in chitosan concentration in F2 (D:C:A = 2:10:30) has shown an entrapment efficiency of 81%. But the comparative further increase of chitosan concentration in F3 (D:C:A = 2:15:30) has shown a entrapment of 80% which is not having any remarkable difference from F2. The FTIR analysis of drug, polymers and the formulations indicated the compatibility of the drug with the polymers. The smoothness of microspheres in F2 & F3 was confirmed by Scanning Electron Microscopy (SEM). However F1 microsphere has shown more irregular shape comparatively. The DSC studies indicated the absence of drug-polymer interaction in the microspheres. Our XRD studies have revealed that when pure drug exhibits crystalline structure with less dissolution profile

  4. Recent advances in chitosan-based nanoparticulate pulmonary drug delivery.

    PubMed

    Islam, Nazrul; Ferro, Vito

    2016-08-14

    The advent of biodegradable polymer-encapsulated drug nanoparticles has made the pulmonary route of administration an exciting area of drug delivery research. Chitosan, a natural biodegradable and biocompatible polysaccharide has received enormous attention as a carrier for drug delivery. Recently, nanoparticles of chitosan (CS) and its synthetic derivatives have been investigated for the encapsulation and delivery of many drugs with improved targeting and controlled release. Herein, recent advances in the preparation and use of micro-/nanoparticles of chitosan and its derivatives for pulmonary delivery of various therapeutic agents (drugs, genes, vaccines) are reviewed. Although chitosan has wide applications in terms of formulations and routes of drug delivery, this review is focused on pulmonary delivery of drug-encapsulated nanoparticles of chitosan and its derivatives. In addition, the controversial toxicological effects of chitosan nanoparticles for lung delivery will also be discussed. PMID:27439116

  5. Recent advances in chitosan-based nanoparticulate pulmonary drug delivery

    NASA Astrophysics Data System (ADS)

    Islam, Nazrul; Ferro, Vito

    2016-07-01

    The advent of biodegradable polymer-encapsulated drug nanoparticles has made the pulmonary route of administration an exciting area of drug delivery research. Chitosan, a natural biodegradable and biocompatible polysaccharide has received enormous attention as a carrier for drug delivery. Recently, nanoparticles of chitosan (CS) and its synthetic derivatives have been investigated for the encapsulation and delivery of many drugs with improved targeting and controlled release. Herein, recent advances in the preparation and use of micro-/nanoparticles of chitosan and its derivatives for pulmonary delivery of various therapeutic agents (drugs, genes, vaccines) are reviewed. Although chitosan has wide applications in terms of formulations and routes of drug delivery, this review is focused on pulmonary delivery of drug-encapsulated nanoparticles of chitosan and its derivatives. In addition, the controversial toxicological effects of chitosan nanoparticles for lung delivery will also be discussed.

  6. Exploiting the Immunomodulatory Properties of Chemotherapeutic Drugs to Improve the Success of Cancer Immunotherapy

    PubMed Central

    Kersten, Kelly; Salvagno, Camilla; de Visser, Karin E.

    2015-01-01

    Cancer immunotherapy is gaining momentum in the clinic. The current challenge is to understand why a proportion of cancer patients do not respond to cancer immunotherapy, and how this can be translated into the rational design of combinatorial cancer immunotherapy strategies aimed at maximizing success of immunotherapy. Here, we discuss how tumors orchestrate an immunosuppressive microenvironment, which contributes to their escape from immune attack. Relieving the immunosuppressive networks in cancer patients is an attractive strategy to extend the clinical success of cancer immunotherapy. Since the clinical availability of drugs specifically targeting immunosuppressive cells or mediators is still limited, an alternative strategy is to use conventional chemotherapy drugs with immunomodulatory properties to improve cancer immunotherapy. We summarize the preclinical and clinical studies that illustrate how the anti-tumor T cell response can be enhanced by chemotherapy-induced relief of immunosuppressive networks. Treatment strategies aimed at combining chemotherapy-induced relief of immunosuppression and T cell-boosting checkpoint inhibitors provide an attractive and clinically feasible approach to overcome intrinsic and acquired resistance to cancer immunotherapy, and to extend the clinical success of cancer immunotherapy. PMID:26500653

  7. Ultrasonically triggered drug delivery: breaking the barrier.

    PubMed

    Husseini, Ghaleb A; Pitt, William G; Martins, Ana M

    2014-11-01

    The adverse side-effects of chemotherapy can be minimized by delivering the therapeutics in time and space to only the desired target site. Ultrasound offers one fairly non-invasive method of accomplishing such precise delivery because its energy can disrupt nanosized containers that are designed to sequester the drug until the ultrasonic event. Such containers include micelles, liposomes and solid nanoparticles. Conventional micelles and liposomes are less acoustically sensitive to ultrasound because the strongest forces associated with ultrasound are generated by gas-liquid interfaces, which both of these conventional constructs lack. Acoustically activated carriers often incorporate a gas phase, either actively as preformed bubbles, or passively such as taking advantage of dissolved gasses that form bubbles upon insonation. Newer concepts include using liquids that form gas when insonated. This review focuses on the ultrasonically activated delivery of therapeutics from micelles, liposomes and solid particles. In vitro and in vivo results are summarized and discussed. Novel structural concepts from micelles and liposomes are presented. Mechanisms of ultrasonically activated release are discussed. The future of ultrasound in drug delivery is envisioned. PMID:25454759

  8. Overview on gastroretentive drug delivery systems for improving drug bioavailability.

    PubMed

    Lopes, Carla M; Bettencourt, Catarina; Rossi, Alessandra; Buttini, Francesca; Barata, Pedro

    2016-08-20

    In recent decades, many efforts have been made in order to improve drug bioavailability after oral administration. Gastroretentive drug delivery systems are a good example; they emerged to enhance the bioavailability and effectiveness of drugs with a narrow absorption window in the upper gastrointestinal tract and/or to promote local activity in the stomach and duodenum. Several strategies are used to increase the gastric residence time, namely bioadhesive or mucoadhesive systems, expandable systems, high-density systems, floating systems, superporous hydrogels and magnetic systems. The present review highlights some of the drugs that can benefit from gastroretentive strategies, such as the factors that influence gastric retention time and the mechanism of action of gastroretentive systems, as well as their classification into single and multiple unit systems. PMID:27173823

  9. [Anti-HIV drugs and drug delivery system].

    PubMed

    Obaru, K; Mitsuya, H

    1998-03-01

    A number of candidate drugs for therapy of HIV-1 infection which show significant activity against the virus in vitro were reported; however, many of them have been dropped from drug development due to (i) insufficient intracellular activation in certain human target cells (particularly in case of nucleoside reverse transcriptase inhibitors), (ii) poor pharmacokinetic profiles, or (iii) intolerable in vitro and/or in vivo toxicities. To circumvent some of these problems, certain drug delivery systems have been applied and several candidate drugs including two novel nucleoside reverse transcriptase inhibitors, abacavir and adefovir, have acquired favorable properties in the clinical setting. This paper reviews several avenues for developing prodrugs of anti-HIV-1 agents to overcome their inherent limitations. PMID:9549371

  10. Polymeric drug delivery for the treatment of glioblastoma

    PubMed Central

    Wait, Scott D.; Prabhu, Roshan S.; Burri, Stuart H.; Atkins, Tyler G.; Asher, Anthony L.

    2015-01-01

    Glioblastoma (GBM) remains an almost universally fatal diagnosis. The current therapeutic mainstay consists of maximal safe surgical resection followed by radiation therapy (RT) with concomitant temozolomide (TMZ), followed by monthly TMZ (the “Stupp regimen”). Several chemotherapeutic agents have been shown to have modest efficacy in the treatment of high-grade glioma (HGG), but blood-brain barrier impermeability remains a major delivery obstacle. Polymeric drug-delivery systems, developed to allow controlled local release of biologically active substances for a variety of conditions, can achieve high local concentrations of active agents while limiting systemic toxicities. Polymerically delivered carmustine (BCNU) wafers, placed on the surface of the tumor-resection cavity, can potentially provide immediate chemotherapy to residual tumor cells during the standard delay between surgery and chemoradiotherapy. BCNU wafer implantation as monochemotherapy (with RT) in newly diagnosed HGG has been investigated in 2 phase III studies that reported significant increases in median overall survival. A number of studies have investigated the tumoricidal synergies of combination chemotherapy with BCNU wafers in newly diagnosed or recurrent HGG, and a primary research focus has been the integration of BCNU wafers into multimodality therapy with the standard Stupp regimen. Overall, the results of these studies have been encouraging in terms of safety and efficacy. However, the data must be qualified by the nature of the studies conducted. Currently, there are no phase III studies of BCNU wafers with the standard Stupp regimen. We review the rationale, biochemistry, pharmacokinetics, and research history (including toxicity profile) of this modality. PMID:25746091

  11. Oral drug delivery systems comprising altered geometric configurations for controlled drug delivery.

    PubMed

    Moodley, Kovanya; Pillay, Viness; Choonara, Yahya E; du Toit, Lisa C; Ndesendo, Valence M K; Kumar, Pradeep; Cooppan, Shivaan; Bawa, Priya

    2012-01-01

    Recent pharmaceutical research has focused on controlled drug delivery having an advantage over conventional methods. Adequate controlled plasma drug levels, reduced side effects as well as improved patient compliance are some of the benefits that these systems may offer. Controlled delivery systems that can provide zero-order drug delivery have the potential for maximizing efficacy while minimizing dose frequency and toxicity. Thus, zero-order drug release is ideal in a large area of drug delivery which has therefore led to the development of various technologies with such drug release patterns. Systems such as multilayered tablets and other geometrically altered devices have been created to perform this function. One of the principles of multilayered tablets involves creating a constant surface area for release. Polymeric materials play an important role in the functioning of these systems. Technologies developed to date include among others: Geomatrix(®) multilayered tablets, which utilizes specific polymers that may act as barriers to control drug release; Procise(®), which has a core with an aperture that can be modified to achieve various types of drug release; core-in-cup tablets, where the core matrix is coated on one surface while the circumference forms a cup around it; donut-shaped devices, which possess a centrally-placed aperture hole and Dome Matrix(®) as well as "release modules assemblage", which can offer alternating drug release patterns. This review discusses the novel altered geometric system technologies that have been developed to provide controlled drug release, also focusing on polymers that have been employed in such developments. PMID:22312236

  12. Oral Drug Delivery Systems Comprising Altered Geometric Configurations for Controlled Drug Delivery

    PubMed Central

    Moodley, Kovanya; Pillay, Viness; Choonara, Yahya E.; du Toit, Lisa C.; Ndesendo, Valence M. K.; Kumar, Pradeep; Cooppan, Shivaan; Bawa, Priya

    2012-01-01

    Recent pharmaceutical research has focused on controlled drug delivery having an advantage over conventional methods. Adequate controlled plasma drug levels, reduced side effects as well as improved patient compliance are some of the benefits that these systems may offer. Controlled delivery systems that can provide zero-order drug delivery have the potential for maximizing efficacy while minimizing dose frequency and toxicity. Thus, zero-order drug release is ideal in a large area of drug delivery which has therefore led to the development of various technologies with such drug release patterns. Systems such as multilayered tablets and other geometrically altered devices have been created to perform this function. One of the principles of multilayered tablets involves creating a constant surface area for release. Polymeric materials play an important role in the functioning of these systems. Technologies developed to date include among others: Geomatrix® multilayered tablets, which utilizes specific polymers that may act as barriers to control drug release; Procise®, which has a core with an aperture that can be modified to achieve various types of drug release; core-in-cup tablets, where the core matrix is coated on one surface while the circumference forms a cup around it; donut-shaped devices, which possess a centrally-placed aperture hole and Dome Matrix® as well as “release modules assemblage”, which can offer alternating drug release patterns. This review discusses the novel altered geometric system technologies that have been developed to provide controlled drug release, also focusing on polymers that have been employed in such developments. PMID:22312236

  13. Topical Drug Delivery for Chronic Rhinosinusitis

    PubMed Central

    Liang, Jonathan; Lane, Andrew P.

    2013-01-01

    Chronic rhinosinusitis is a multifactorial disorder that may be heterogeneous in presentation and clinical course. While the introduction of endoscopic sinus surgery revolutionized surgical management and has led to significantly improved patient outcomes, medical therapy remains the foundation of long-term care of chronic rhinosinusitis, particularly in surgically recalcitrant cases. A variety of devices and pharmaceutical agents have been developed to apply topical medical therapy to the sinuses, taking advantage of the access provided by endoscopic surgery. The goal of topical therapy is to address the inflammation, infection, and mucociliary dysfunction that underlies the disease. Major factors that impact success include the patient’s sinus anatomy and the dynamics of the delivery device. Despite a growing number of topical treatment options, the evidence-based literature to support their use is limited. In this article, we comprehensively review current delivery methods and the available topical agents. We also discuss biotechnological advances that promise enhanced delivery in the future, and evolving pharmacotherapeutical compounds that may be added to rhinologist’s armamentarium. A complete understand of topical drug delivery is increasingly essential to the management of chronic rhinosinusitis when traditional forms of medical therapy and surgery have failed. PMID:23525506

  14. Drug and cell delivery for cardiac regeneration.

    PubMed

    Hastings, Conn L; Roche, Ellen T; Ruiz-Hernandez, Eduardo; Schenke-Layland, Katja; Walsh, Conor J; Duffy, Garry P

    2015-04-01

    The spectrum of ischaemic cardiomyopathy, encompassing acute myocardial infarction to congestive heart failure is a significant clinical issue in the modern era. This group of diseases is an enormous source of morbidity and mortality and underlies significant healthcare costs worldwide. Cardiac regenerative therapy, whereby pro-regenerative cells, drugs or growth factors are administered to damaged and ischaemic myocardium has demonstrated significant potential, especially preclinically. While some of these strategies have demonstrated a measure of success in clinical trials, tangible clinical translation has been slow. To date, the majority of clinical studies and a significant number of preclinical studies have utilised relatively simple delivery methods for regenerative therapeutics, such as simple systemic administration or local injection in saline carrier vehicles. Here, we review cardiac regenerative strategies with a particular focus on advanced delivery concepts as a potential means to enhance treatment efficacy and tolerability and ultimately, clinical translation. These include (i) delivery of therapeutic agents in biomaterial carriers, (ii) nanoparticulate encapsulation, (iii) multimodal therapeutic strategies and (iv) localised, minimally invasive delivery via percutaneous transcatheter systems. PMID:25172834

  15. Logical enzyme triggered (LET) layer-by-layer nanocapsules for drug delivery system

    NASA Astrophysics Data System (ADS)

    Kelley, Marie-Michelle

    Breast cancer is the second leading cause of morbidity and mortality among women in the United States. Early detection and treatment methods have resulted in 100% 5-year survival rates for stage 0-I breast cancer. Unfortunately, the 5-year survival rate of metastatic breast cancer (stage IV) is reduced fivefold. The most challenging issues of metastatic breast cancer treatment are the ability to selectively target the adenoma and adenocarcinoma cells both in their location of origin and as they metastasize following initial treatment. Multilayer/Layer-by-Layer (LbL) nanocapsules have garnered vast interest as anticancer drug delivery systems due to their ability to be easily modified, their capacity to encapsulate a wide range of chemicals and proteins, and their improved pharmacokinetics. Multilayer nanocapsule formation requires the layering of opposing charged polyelectrolytic polymers over a removable core nanoparticle. Our goal is to have a programmable nanocapsules degrade only after receiving and validating specific breast cancer biomarkers. The overall objective is to fabricate a novel programmable LbL nanocapsule with a specific logical system that will enhance functions pertinent to drug delivery systems. Our central hypothesis is that LbL technology coupled with extracellular matrix (ECM) protein substrates will result in a logical enzyme triggered LbL nanocapsule drug delivery system. This platform represents a novel approach toward a logically regulated nano-encapsulated cancer therapy that can selectively follow and deliver chemotherapeutics to cancer cells. The rationale for this project is to overcome a crucial limitation of existing drug delivery systems where chemotherapeutic can be erroneously delivered to non-carcinogenic cells.

  16. Drug accumulation by means of noninvasive magnetic drug delivery system

    NASA Astrophysics Data System (ADS)

    Chuzawa, M.; Mishima, F.; Akiyama, Y.; Nishijima, S.

    2011-11-01

    The medication is one of the most general treatment methods, but drugs diffuse in the normal tissues other than the target part by the blood circulation. Therefore, side effect in the medication, particularly for a drug with strong effect such as anti-cancer drug, are a serious issue. Drug Delivery System (DDS) which accumulates the drug locally in the human body is one of the techniques to solve the side-effects. Magnetic Drug Delivery System (MDDS) is one of the active DDSs, which uses the magnetic force. The objective of this study is to accumulate the ferromagnetic drugs noninvasively in the deep part of the body by using MDDS. It is necessary to generate high magnetic field and magnetic gradient at the target part to reduce the side-effects to the tissues with no diseases. The biomimetic model was composed, which consists of multiple model organs connected with diverged blood vessel model. The arrangement of magnetic field was examined to accumulate ferromagnetic drug particles in the target model organ by using a superconducting bulk magnet which can generate high magnetic fields. The arrangement of magnet was designed to generate high and stable magnetic field at the target model organ. The accumulation experiment of ferromagnetic particles has been conducted. In this study, rotating HTS bulk magnet around the axis of blood vessels by centering on the target part was suggested, and the model experiment for magnet rotation was conducted. As a result, the accumulation of the ferromagnetic particles to the target model organ in the deep part was confirmed.

  17. In vitro Antiproliferative Activity of Benzopyranone Derivatives in Comparison with Standard Chemotherapeutic Drugs

    PubMed Central

    Musa, Musiliyu A.; Cooperwood, John S.; Khan, M. Omar F.; Rahman, Taufiq

    2012-01-01

    SUMMARY The cytotoxic activities of five new benzopyranone derivatives containing basic amino side chain are described. Their cytotoxicities against ER (+) MCF-7 and ER (−) MDA-MB-231 human breast cancer cell lines, and Ishikawa human endometrial cell line were determined after 72 h drug exposure employing CellTiter-Glo assay at concentrations ranging from 0.01 – 1.0 × 105 nM. The antiproliferative activities of these compounds were compared to tamoxifen (TAM), 4-hydroxytamoxifen (4-OHT, active metabolite of tamoxifen) and raloxifene (RAL). In vitro results indicated that compounds 9, 10, 12 and 13 were more potent than TAM against the human breast cancer cell lines with IC50 < 20 µM. The in silico structure-activity relationships of these compounds and their binding mode within the estrogen receptor (ER) binding site using AutoDock vina are discussed. PMID:21290426

  18. Hydrogel-Coated Near Infrared Absorbing Nanoshells as Light-Responsive Drug Delivery Vehicles

    PubMed Central

    2015-01-01

    Nanoparticle drug delivery carriers that can modulate drug release based on an exogenous signal, such as light, are of great interest, especially for improving cancer therapy. A light-activated delivery vehicle was fabricated by synthesizing a thin, thermally responsive poly(N-isopropylacrylamide-co-acrylamide) hydrogel coating directly onto the surfaces of individual near-infrared (NIR) absorbing gold-silica nanoshells. This hydrogel was designed to be in a swollen state under physiological conditions and expel large amounts of water, along with any entrapped drug, at elevated temperatures. The required temperature change can be achieved via NIR absorption by the nanoshell, allowing the hydrogel phase change to be triggered by light, which was observed by monitoring changes in particle sizes as water was expelled from the hydrogel network. The phase change was reversible and repeatable. As a model drug, the chemotherapeutic doxorubicin was loaded into this delivery vehicle, and rapid release of doxorubicin occurred upon NIR exposure. Further, colon carcinoma cells exposed to the irradiated platform displayed nearly 3 times as much doxorubicin uptake as cells exposed to nonirradiated particles or free drug, which in turn resulted in a higher loss of cell viability. We hypothesize these effects are because the NIR-mediated heating results in a transient increase in cell membrane permeability, thus aiding in cellular uptake of the drug. PMID:26366438

  19. Micro- and nano-fabricated implantable drug-delivery systems

    PubMed Central

    Meng, Ellis; Hoang, Tuan

    2013-01-01

    Implantable drug-delivery systems provide new means for achieving therapeutic drug concentrations over entire treatment durations in order to optimize drug action. This article focuses on new drug administration modalities achieved using implantable drug-delivery systems that are enabled by micro- and nano-fabrication technologies, and microfluidics. Recent advances in drug administration technologies are discussed and remaining challenges are highlighted. PMID:23323562

  20. Adenovirus Dodecahedron, as a Drug Delivery Vector

    PubMed Central

    Zochowska, Monika; Paca, Agnieszka; Schoehn, Guy; Andrieu, Jean-Pierre; Chroboczek, Jadwiga; Dublet, Bernard; Szolajska, Ewa

    2009-01-01

    Background Bleomycin (BLM) is an anticancer antibiotic used in many cancer regimens. Its utility is limited by systemic toxicity and dose-dependent pneumonitis able to progress to lung fibrosis. The latter can affect up to nearly 50% of the total patient population, out of which 3% will die. We propose to improve BLM delivery by tethering it to an efficient delivery vector. Adenovirus (Ad) dodecahedron base (DB) is a particulate vector composed of 12 copies of a pentameric viral protein responsible for virus penetration. The vector efficiently penetrates the plasma membrane, is liberated in the cytoplasm and has a propensity to concentrate around the nucleus; up to 300000 particles can be observed in one cell in vitro. Principal Findings Dodecahedron (Dd) structure is preserved at up to about 50°C at pH 7–8 and during dialysis, freezing and drying in the speed-vac in the presence of 150 mM ammonium sulfate, as well as during lyophilization in the presence of cryoprotectants. The vector is also stable in human serum for 2 h at 37°C. We prepared a Dd-BLM conjugate which upon penetration induced death of transformed cells. Similarly to free bleomycin, Dd-BLM caused dsDNA breaks. Significantly, effective cytotoxic concentration of BLM delivered with Dd was 100 times lower than that of free bleomycin. Conclusions/Significance Stability studies show that Dds can be conveniently stored and transported, and can potentially be used for therapeutic purposes under various climates. Successful BLM delivery by Ad Dds demonstrates that the use of virus like particle (VLP) results in significantly improved drug bioavailability. These experiments open new vistas for delivery of non-permeant labile drugs. PMID:19440379

  1. In Vitro Polyvinylformaldehyde Particle Compatibility with Chemotherapeutic Drugs Used for Chemoembolization Therapy

    SciTech Connect

    Vallee, Jean-Noel E-mail: jean-noel.vallee@psl.ap-hop-paris.fr; Guillevin, Remy; Lo, Daouda; Adem, Carmen; Benois, Florence; Chiras, Jacques

    2003-06-15

    Purpose: Because the effects of pirarubicin and carboplatin on the physical structure of particles made from polyvinylformaldehyde are not well known, we describe an experiment to test the in vitro polyvinylformaldehyde particle compatibility with these drugs used for chemoembolization of bone metastases. Materials and Methods: Polyvinylformaldehydeparticles (Ultra-Drivalon) were mixed in vitro with either pirarubicinor carboplatin as experimental samples, and with distilled water as control samples, and left for 24 h at 37{sup o}C. The particles used measured 150-250 {mu}m and 600-1000 {mu}m in diameter. Particle morphology, including appearance, overall shape, and surface characteristics were examined using a microscope equipped with a videocamera. Particle size was measured by granulometry. Qualitative and quantitative variables were analyzed using, respectively, the two-sided Fisher's exact test and the Wilcoxon signed-rank rank test for paired values, with a significance level of 0.05. Results: No broken particles or microscopic degradations in the appearance, overall shape, or surface characteristics of any particles were observed. The particle size distribution was not significantly different between the experimental samples containing pirarubicin or carboplatin and the control sample of particles with diameters in the same range. Conclusion: Particles made from polyvinylformaldehyde can be mixed with pirarubicin or carboplatin without any risk of damaging their physical properties.

  2. Effect of dicycloplatin, a novel platinum chemotherapeutical drug, on inhibiting cell growth and inducing cell apoptosis.

    PubMed

    Li, Guang-quan; Chen, Xing-gui; Wu, Xing-ping; Xie, Jing-dun; Liang, Yong-ju; Zhao, Xiao-qin; Chen, Wei-qiang; Fu, Li-wu

    2012-01-01

    Dicycloplatin, a new supramolecular platinum-based antitumor drug, has been approved by the State Food and Administration (SFDA) of China. In this study, we investigated the anticancer activity of dicycloplatin in cancer cells and signaling pathways involved in dicycloplatin-induced apoptosis. Dicycloplatin inhibited the proliferation of cancer cells and increased the percentage of apoptosis in a concentration-dependent manner. Besides, some apoptosis related events were observed after treatment with dicycloplatin, including increase of reactive oxygen species (ROS), collapse of mitochondrial membrane potential (Δψm), release of cytochrome c from the mitochondria to the cytosol, upregulation of p53, which were accompanied by activation of caspase-9, caspase-3, caspase-8, and poly (ADP-ribose) polymerase cleavage in a concentration-dependent manner. The role of apoptosis in dicycloplatin-mediated cell death was further confirmed by the concomitant treatment with caspase-8 or caspase-9 inhibitors, which inhibited apoptosis and PARP cleavage. Intracellular glutathione (GSH) was also found to inhibit the cytotoxic effect of dicycloplatin. In conclusion, these findings suggest that dicycloplatin induces apoptosis through ROS stress-mediated death receptor pathway and mitochondrial pathway which is similar to carboplatin. PMID:23152837

  3. Nanodiamonds as novel nanomaterials for biomedical applications: drug delivery and imaging systems

    PubMed Central

    Kaur, Randeep; Badea, Ildiko

    2013-01-01

    Detonation nanodiamonds (NDs) are emerging as delivery vehicles for small chemical drugs and macromolecular biotechnology products due to their primary particle size of 4 to 5 nm, stable inert core, reactive surface, and ability to form hydrogels. Nanoprobe technology capitalizes on the intrinsic fluorescence, high refractive index, and unique Raman signal of the NDs, rendering them attractive for in vitro and in vivo imaging applications. This review provides a brief introduction of the various types of NDs and describes the development of procedures that have led to stable single-digit-sized ND dispersions, a crucial feature for drug delivery systems and nanoprobes. Various approaches used for functionalizing the surface of NDs are highlighted, along with a discussion of their biocompatibility status. The utilization of NDs to provide sustained release and improve the dispersion of hydrophobic molecules, of which chemotherapeutic drugs are the most investigated, is described. The prospects of improving the intracellular delivery of nucleic acids by using NDs as a platform are exemplified. The photoluminescent and optical scattering properties of NDs, together with their applications in cellular labeling, are also reviewed. Considering the progress that has been made in understanding the properties of NDs, they can be envisioned as highly efficient drug delivery and imaging biomaterials for use in animals and humans. PMID:23326195

  4. Biomedical Imaging in Implantable Drug Delivery Systems

    PubMed Central

    Zhou, Haoyan; Hernandez, Christopher; Goss, Monika; Gawlik, Anna; Exner, Agata A.

    2015-01-01

    Implantable drug delivery systems (DDS) provide a platform for sustained release of therapeutic agents over a period of weeks to months and sometimes years. Such strategies are typically used clinically to increase patient compliance by replacing frequent administration of drugs such as contraceptives and hormones to maintain plasma concentration within the therapeutic window. Implantable or injectable systems have also been investigated as a means of local drug administration which favors high drug concentration at a site of interest, such as a tumor, while reducing systemic drug exposure to minimize unwanted side effects. Significant advances in the field of local DDS have led to increasingly sophisticated technology with new challenges including quantification of local and systemic pharmacokinetics and implant-body interactions. Because many of these sought-after parameters are highly dependent on the tissue properties at the implantation site, and rarely represented adequately with in vitro models, new nondestructive techniques that can be used to study implants in situ are highly desirable. Versatile imaging tools can meet this need and provide quantitative data on morphological and functional aspects of implantable systems. The focus of this review article is an overview of current biomedical imaging techniques, including magnetic resonance imaging (MRI), ultrasound imaging, optical imaging, X-ray and computed tomography (CT), and their application in evaluation of implantable DDS. PMID:25418857

  5. Enhancement of therapeutic drug and DNA delivery into cells by electroporation* Enhancement of therapeutic drug and DNA delivery into cells by electroporation

    NASA Astrophysics Data System (ADS)

    Rabussay, Dietmar; Dev, Nagendu B.; Fewell, Jason; Smith, Louis C.; Widera, Georg; Zhang, Lei

    2003-02-01

    The effectiveness of potentially powerful therapeutics, including DNA, is often limited by their inability to permeate the cell membrane efficiently. Electroporation (EP) also referred to as `electropermeabilization' of the outer cell membrane renders this barrier temporarily permeable by inducing `pores' across the lipid bilayer. For in vivo EP, the drug or DNA is delivered into the interstitial space of the target tissue by conventional means, followed by local EP. EP pulses of micro- to millisecond duration and field strengths of 100-1500 V cm-1 generally enhance the delivery of certain chemotherapeutic drugs by three to four orders of magnitude and intracellular delivery of DNA several hundred-fold. We have used EP in clinical studies for human cancer therapy and in animals for gene therapy and DNA vaccination. Late stage squamous cell carcinomas of the head and neck were treated with intratumoural injection of bleomycin and subsequent EP. Of the 69 tumours treated, 25% disappeared completely and another 32% were reduced in volume by more than half. Residence time of bleomycin in electroporated tumours was significantly greater than in non-electroporated lesions. Histological findings and gene expression patterns after bleomycin-EP treatment indicated rapid apoptosis of the majority of tumour cells. In animals, we demonstrated the usefulness of EP for enhanced DNA delivery by achieving normalization of blood clotting times in haemophilic dogs, and by substantially increasing transgene expression in smooth muscle cells of arterial walls using a novel porous balloon EP catheter. Finally, we have found in animal experiments that the immune response to DNA vaccines can be dramatically enhanced and accelerated by EP and co-injection of micron-sized particles. We conclude that EP represents an effective, economical and safe approach to enhance the intracellular delivery, and thus potency, of important drugs and genes for therapeutic purposes. The safety and pharmaco

  6. Transdermal iontophoretic drug delivery: advances and challenges.

    PubMed

    Ita, Kevin

    2016-06-01

    The stratum corneum continues to pose considerable impediment to transdermal drug delivery. One of the effective ways of circumventing this challenge is through the use of iontophoresis. Iontophoresis uses low-level current to drive charged compounds across the skin. This review discusses progress made in the field of iontophoretic transport of small and large molecules. The major obstacles are also touched upon and advances made in the last few decades described. A number of iontophoretic systems approved for clinical use by regulatory authorities is also discussed. PMID:26406291

  7. Laser assisted Drug Delivery: Grundlagen und Praxis.

    PubMed

    Braun, Stephan Alexander; Schrumpf, Holger; Buhren, Bettina Alexandra; Homey, Bernhard; Gerber, Peter Arne

    2016-05-01

    Die topische Applikation von Wirkstoffen ist eine zentrale Therapieoption der Dermatologie. Allerdings mindert die effektive Barrierefunktion der Haut die Bioverfügbarkeit der meisten Externa. Fraktionierte ablative Laser stellen ein innovatives Verfahren dar, um die epidermale Barriere standardisiert, kontaktfrei zu überwinden. Die Bioverfügbarkeit im Anschluss applizierter Externa wird im Sinne einer laser assisted drug delivery (LADD) signifikant gesteigert. Das Prinzip der LADD wird bereits in einigen Bereichen der Dermatologie erfolgreich eingesetzt. Die vorliegende Übersichtsarbeit soll einen Überblick über die aktuellen aber auch perspektivischen Einsatzmöglichkeiten der LADD bieten. PMID:27119467

  8. Dendrimer based nanotherapeutics for ocular drug delivery

    NASA Astrophysics Data System (ADS)

    Kambhampati, Siva Pramodh

    PAMAM dendrimers are a class of well-defined, hyperbranched polymeric nanocarriers that are being investigated for ocular drug and gene delivery. Their favorable properties such as small size, multivalency and water solubility can provide significant opportunities for many biologically unstable drugs and allows potentially favorable ocular biodistribution. This work exploits hydroxyl terminated dendrimers (G4-OH) as drug/gene delivery vehicles that can target retinal microglia and pigment epithelium via systemic delivery with improved efficacy at much lower concentrations without any side effects. Two different drugs Triamcinolone acetonide (TA) and N-Acetyl Cysteine (NAC) conjugated to G4-OH dendrimers showed tailorable sustained release in physiological relevant solutions and were evaluated in-vitro and in-vivo. Dendrimer-TA conjugates enhanced the solubility of TA and were 100 fold more effective at lower concentrations than free TA in its anti-inflammatory activity in activated microglia and in suppressing VEGF production in hypoxic RPE cells. Dendrimers targeted activated microglia/macrophages and RPE and retained for a period of 21 days in I/R mice model. The relative retention of intravitreal and intravenous dendrimers was comparable, if a 30-fold intravenous dose is used; suggesting intravenous route targeting retinal diseases are possible with dendrimers. D-NAC when injected intravenously attenuated retinal and choroidal inflammation, significantly reduced (˜73%) CNV growth at early stage of AMD in rat model of CNV. A combination therapy of D-NAC + D-TA significantly suppressed microglial activation and promoted CNV regression in late stages of AMD without causing side-effects. G4-OH was modified with linker having minimal amine groups and incorporation of TA as a nuclear localization enhancer resulted in compact gene vectors with favorable safety profile and achieved high levels of transgene expression in hard to transfect human retinal pigment

  9. Pulmonary drug delivery by powder aerosols.

    PubMed

    Yang, Michael Yifei; Chan, John Gar Yan; Chan, Hak-Kim

    2014-11-10

    The efficacy of pharmaceutical aerosols relates to its deposition in the clinically relevant regions of the lungs, which can be assessed by in vivo lung deposition studies. Dry powder formulations are popular as devices are portable and aerosolisation does not require a propellant. Over the years, key advancements in dry powder formulation, device design and our understanding on the mechanics of inhaled pharmaceutical aerosol have opened up new opportunities in treatment of diseases through pulmonary drug delivery. This review covers these advancements and future directions for inhaled dry powder aerosols. PMID:24818765

  10. STAT3 Inhibition by Microtubule-Targeted Drugs: Dual Molecular Effects of Chemotherapeutic Agents

    PubMed Central

    Walker, Sarah R.; Chaudhury, Mousumi; Frank, David A.

    2011-01-01

    To improve the effectiveness of anti-cancer therapies, it is necessary to identify molecular targets that are essential to a tumor cell but dispensable in a normal cell. Increasing evidence indicates that the transcription factor STAT3, which regulates the expression of genes controlling proliferation, survival, and self-renewal, constitutes such a target. Recently it has been found that STAT3 can associate with the cytoskeleton. Since many of the tumors in which STAT3 is activated, such as breast cancer and ovarian cancer, are responsive to drugs that target microtubules, we examined the effect of these compounds on STAT3. We found that microtubule stabilizers, such as paclitaxel, or microtubule inhibitors, such as vinorelbine, decrease the activating tyrosine phosphorylation of STAT3 in tumor cells and inhibit the expression of STAT3 target genes. Paclitaxel decreases the association between STAT3 and microtubules, and appears to decrease STAT3 phosphorylation through induction of a negative feedback regulator. The cytotoxic activity of paclitaxel in breast cancer cell lines correlates with its ability to decrease STAT3 phosphorylation. However, consistent with the necessity for expression of a negative regulator, treatment of resistant MDA-MB-231 cells with the DNA demethylating agent 5-azacytidine restores the ability of paclitaxel to block STAT3-dependent gene expression. Finally, the combination of paclitaxel and agents that directly target STAT3 has beneficial effects in killing STAT3-dependent cell lines. Thus, microtubule-targeted agents may exert some of their effects by inhibiting STAT3, and understanding this interaction may be important for optimizing rational targeted cancer therapies. PMID:21949561

  11. Implantable microchip: the futuristic controlled drug delivery system.

    PubMed

    Sutradhar, Kumar Bishwajit; Sumi, Chandra Datta

    2016-01-01

    There is no doubt that controlled and pulsatile drug delivery system is an important challenge in medicine over the conventional drug delivery system in case of therapeutic efficacy. However, the conventional drug delivery systems often offer a limited by their inability to drug delivery which consists of systemic toxicity, narrow therapeutic window, complex dosing schedule for long term treatment etc. Therefore, there has been a search for the drug delivery system that exhibit broad enhancing activity for more drugs with less complication. More recently, some elegant study has noted that, a new type of micro-electrochemical system or MEMS-based drug delivery systems called microchip has been improved to overcome the problems related to conventional drug delivery. Moreover, micro-fabrication technology has enabled to develop the implantable controlled released microchip devices with improved drug administration and patient compliance. In this article, we have presented an overview of the investigations on the feasibility and application of microchip as an advanced drug delivery system. Commercial manufacturing materials and methods, related other research works and current advancement of the microchips for controlled drug delivery have also been summarized. PMID:24758139

  12. Importance of novel drug delivery systems in herbal medicines.

    PubMed

    Devi, V Kusum; Jain, Nimisha; Valli, Kusum S

    2010-01-01

    Novel drug delivery system is a novel approach to drug delivery that addresses the limitations of the traditional drug delivery systems. Our country has a vast knowledge base of Ayurveda whose potential is only being realized in the recent years. However, the drug delivery system used for administering the herbal medicine to the patient is traditional and out-of-date, resulting in reduced efficacy of the drug. If the novel drug delivery technology is applied in herbal medicine, it may help in increasing the efficacy and reducing the side effects of various herbal compounds and herbs. This is the basic idea behind incorporating novel method of drug delivery in herbal medicines. Thus it is important to integrate novel drug delivery system and Indian Ayurvedic medicines to combat more serious diseases. For a long time herbal medicines were not considered for development as novel formulations owing to lack of scientific justification and processing difficulties, such as standardization, extraction and identification of individual drug components in complex polyherbal systems. However, modern phytopharmaceutical research can solve the scientific needs (such as determination of pharmacokinetics, mechanism of action, site of action, accurate dose required etc.) of herbal medicines to be incorporated in novel drug delivery system, such as nanoparticles, microemulsions, matrix systems, solid dispersions, liposomes, solid lipid nanoparticles and so on. This article summarizes various drug delivery technologies, which can be used for herbal actives together with some examples. PMID:22228938

  13. Ultrasound-Propelled Nanocups for Drug Delivery

    PubMed Central

    Kwan, James J; Myers, Rachel; Coviello, Christian M; Graham, Susan M; Shah, Apurva R; Stride, Eleanor; Carlisle, Robert C; Coussios, Constantin C

    2015-01-01

    Ultrasound-induced bubble activity (cavitation) has been recently shown to actively transport and improve the distribution of therapeutic agents in tumors. However, existing cavitation-promoting agents are micron-sized and cannot sustain cavitation activity over prolonged time periods because they are rapidly destroyed upon ultrasound exposure. A novel ultrasound-responsive single-cavity polymeric nanoparticle (nanocup) capable of trapping and stabilizing gas against dissolution in the bloodstream is reported. Upon ultrasound exposure at frequencies and intensities achievable with existing diagnostic and therapeutic systems, nanocups initiate and sustain readily detectable cavitation activity for at least four times longer than existing microbubble constructs in an in vivo tumor model. As a proof-of-concept of their ability to enhance the delivery of unmodified therapeutics, intravenously injected nanocups are also found to improve the distribution of a freely circulating IgG mouse antibody when the tumor is exposed to ultrasound. Quantification of the delivery distance and concentration of both the nanocups and coadministered model therapeutic in an in vitro flow phantom shows that the ultrasound-propelled nanocups travel further than the model therapeutic, which is itself delivered to hundreds of microns from the vessel wall. Thus nanocups offer considerable potential for enhanced drug delivery and treatment monitoring in oncological and other biomedical applications. PMID:26296985

  14. Smart Nanoparticles for Drug Delivery: Boundaries and Opportunities

    PubMed Central

    Lee, Byung Kook; Yun, Yeon Hee; Park, Kinam

    2014-01-01

    Various pharmaceutical particles have been used in developing different drug delivery systems ranging from traditional tablets to state-of-the-art nanoparticle formulations. Nanoparticle formulations are unique in that the small size with huge surface area sometimes provides unique properties that larger particles and bulk materials do not have. Nanoparticle formulations have been used in improving the bioavailability of various drugs, in particular, poorly soluble drugs. Nanoparticle drug delivery systems have found their unique applications in targeted drug delivery to tumors. While nanoparticle formulations have been successful in small animal xenograft models, their translation to clinical applications has been very rare. Developing nanoparticle systems designed for targeted drug delivery, e.g., treating tumors in humans, requires clear understanding of the uniqueness of nanoparticles, as well as limitations and causes of failures in clinical applications. It also requires designing novel smart nanoparticle delivery systems that can increase the drug bioavailability and at the same time reduce the drug's side effects. PMID:25684780

  15. Vascular Permeability and Drug Delivery in Cancers

    PubMed Central

    Azzi, Sandy; Hebda, Jagoda K.; Gavard, Julie

    2013-01-01

    The endothelial barrier strictly maintains vascular and tissue homeostasis, and therefore modulates many physiological processes such as angiogenesis, immune responses, and dynamic exchanges throughout organs. Consequently, alteration of this finely tuned function may have devastating consequences for the organism. This is particularly obvious in cancers, where a disorganized and leaky blood vessel network irrigates solid tumors. In this context, vascular permeability drives tumor-induced angiogenesis, blood flow disturbances, inflammatory cell infiltration, and tumor cell extravasation. This can directly restrain the efficacy of conventional therapies by limiting intravenous drug delivery. Indeed, for more effective anti-angiogenic therapies, it is now accepted that not only should excessive angiogenesis be alleviated, but also that the tumor vasculature needs to be normalized. Recovery of normal state vasculature requires diminishing hyperpermeability, increasing pericyte coverage, and restoring the basement membrane, to subsequently reduce hypoxia, and interstitial fluid pressure. In this review, we will introduce how vascular permeability accompanies tumor progression and, as a collateral damage, impacts on efficient drug delivery. The molecular mechanisms involved in tumor-driven vascular permeability will next be detailed, with a particular focus on the main factors produced by tumor cells, especially the emblematic vascular endothelial growth factor. Finally, new perspectives in cancer therapy will be presented, centered on the use of anti-permeability factors and normalization agents. PMID:23967403

  16. Polymeric Micelles for Acyclovir Drug Delivery

    PubMed Central

    Sawdon, Alicia J.; Peng, Ching-An

    2014-01-01

    Polymeric prodrug micelles for delivery of acyclovir (ACV) were synthesized. First, ACV was used directly to initiate ring-opening polymerization of ε-caprolactone to form ACV-polycaprolactone (ACV-PCL). Through conjugation of hydrophobic ACV-PCL with hydrophilic methoxy poly(ethylene glycol) (MPEG) or chitosan, polymeric micelles for drug delivery were formed. 1H NMR, FTIR, and gel permeation chromatography were employed to show successful conjugation of MPEG or chitosan to hydrophobic ACV-PCL. Through dynamic light scattering, zeta potential analysis, transmission electron microscopy, and critical micelle concentration (CMC), the synthesized ACV-tagged polymeric micelles were characterized. It was found that the average size of the polymeric micelles was under 200 nm and the CMCs of ACV-PCLMPEG and ACV-PCL-chitosan were 2.0 mg L−1 and 6.6 mg L−1, respectively. The drug release kinetics of ACV was investigated and cytotoxicity assay demonstrates that ACV-tagged polymeric micelles were non-toxic. PMID:25193154

  17. Diatomite silica nanoparticles for drug delivery

    PubMed Central

    2014-01-01

    Diatomite is a natural fossil material of sedimentary origin, constituted by fragments of diatom siliceous skeletons. In this preliminary work, the properties of diatomite nanoparticles as potential system for the delivery of drugs in cancer cells were exploited. A purification procedure, based on thermal treatments in strong acid solutions, was used to remove inorganic and organic impurities from diatomite and to make them a safe material for medical applications. The micrometric diatomite powder was reduced in nanoparticles by mechanical crushing, sonication, and filtering. Morphological analysis performed by dynamic light scattering and transmission electron microscopy reveals a particles size included between 100 and 300 nm. Diatomite nanoparticles were functionalized by 3-aminopropyltriethoxysilane and labeled by tetramethylrhodamine isothiocyanate. Different concentrations of chemically modified nanoparticles were incubated with cancer cells and confocal microscopy was performed. Imaging analysis showed an efficient cellular uptake and homogeneous distribution of nanoparticles in cytoplasm and nucleus, thus suggesting their potentiality as nanocarriers for drug delivery. PACS 87.85.J81.05.Rm; 61.46. + w PMID:25024689

  18. Challenges in modelling nanoparticles for drug delivery

    NASA Astrophysics Data System (ADS)

    Barnard, Amanda S.

    2016-01-01

    Although there have been significant advances in the fields of theoretical condensed matter and computational physics, when confronted with the complexity and diversity of nanoparticles available in conventional laboratories a number of modeling challenges remain. These challenges are generally shared among application domains, but the impacts of the limitations and approximations we make to overcome them (or circumvent them) can be more significant one area than another. In the case of nanoparticles for drug delivery applications some immediate challenges include the incompatibility of length-scales, our ability to model weak interactions and solvation, the complexity of the thermochemical environment surrounding the nanoparticles, and the role of polydispersivity in determining properties and performance. Some of these challenges can be met with existing technologies, others with emerging technologies including the data-driven sciences; some others require new methods to be developed. In this article we will briefly review some simple methods and techniques that can be applied to these (and other) challenges, and demonstrate some results using nanodiamond-based drug delivery platforms as an exemplar.

  19. Cooperative assembly in targeted drug delivery

    NASA Astrophysics Data System (ADS)

    Auguste, Debra

    2012-02-01

    Described as cell analogues, liposomes are self-assembled lipid bilayer spheres that encapsulate aqueous volumes. Liposomes offer several drug delivery advantages due to their structural versatility related to size, composition, bilayer fluidity, and ability to encapsulate a large variety of compounds non-covalently. However, liposomes lack the structural information embedded within cell membranes. Partitioning of unsaturated and saturated lipids into liquid crystalline (Lα) and gel phase (Lβ) domains, respectively, affects local molecular diffusion and elasticity. Liposome microdomains may be used to pattern molecules, such as antibodies, on the liposome surface to create concentrated, segregated binding regions. We have synthesized, characterized, and evaluated a series of homogeneous and heterogeneous liposomal vehicles that target inflamed endothelium. These drug delivery vehicles are designed to complement the heterogeneous presentation of lipids and receptors on endothelial cells (ECs). EC surfaces are dynamic; they segregate receptors within saturated lipid microdomains on the cell surface to regulate binding and signaling events. We have demonstrated that cooperative binding of two antibodies enhances targeting by multiple fold. Further, we have shown that organization of these antibodies on the surface can further enhance cell uptake. The data suggest that EC targeting may be enhanced by designing liposomes that mirror the segregated structure of lipid and receptor molecules involved in neutrophil-EC adhesion. This strategy is employed in an atherosclerotic mouse model in vivo.

  20. Vaults engineered for hydrophobic drug delivery.

    PubMed

    Buehler, Daniel C; Toso, Daniel B; Kickhoefer, Valerie A; Zhou, Z Hong; Rome, Leonard H

    2011-05-23

    The vault nanoparticle is one of the largest known ribonucleoprotein complexes in the sub-100 nm range. Highly conserved and almost ubiquitously expressed in eukaryotes, vaults form a large nanocapsule with a barrel-shaped morphology surrounding a large hollow interior. These properties make vaults an ideal candidate for development into a drug delivery vehicle. In this study, the first example of using vaults towards this goal is reported. Recombinant vaults are engineered to encapsulate the highly insoluble and toxic hydrophobic compound all-trans retinoic acid (ATRA) using a vault-binding lipoprotein complex that forms a lipid bilayer nanodisk. These recombinant vaults offer protection to the encapsulated ATRA from external elements. Furthermore, a cryo-electron tomography (cryo-ET) reconstruction shows the vault-binding lipoprotein complex sequestered within the vault lumen. Finally, these ATRA-loaded vaults show enhanced cytotoxicity against the hepatocellular carcinoma cell line HepG2. The ability to package therapeutic compounds into the vault is an important achievement toward their development into a viable and versatile platform for drug delivery. PMID:21506266

  1. Collagen interactions: Drug design and delivery.

    PubMed

    An, Bo; Lin, Yu-Shan; Brodsky, Barbara

    2016-02-01

    Collagen is a major component in a wide range of drug delivery systems and biomaterial applications. Its basic physical and structural properties, together with its low immunogenicity and natural turnover, are keys to its biocompatibility and effectiveness. In addition to its material properties, the collagen triple-helix interacts with a large number of molecules that trigger biological events. Collagen interactions with cell surface receptors regulate many cellular processes, while interactions with other ECM components are critical for matrix structure and remodeling. Collagen also interacts with enzymes involved in its biosynthesis and degradation, including matrix metalloproteinases. Over the past decade, much information has been gained about the nature and specificity of collagen interactions with its partners. These studies have defined collagen sequences responsible for binding and the high-resolution structures of triple-helical peptides bound to its natural binding partners. Strategies to target collagen interactions are already being developed, including the use of monoclonal antibodies to interfere with collagen fibril formation and the use of triple-helical peptides to direct liposomes to melanoma cells. The molecular information about collagen interactions will further serve as a foundation for computational studies to design small molecules that can interfere with specific interactions or target tumor cells. Intelligent control of collagen biological interactions within a material context will expand the effectiveness of collagen-based drug delivery. PMID:26631222

  2. Stimuli-responsive dendrimers in drug delivery.

    PubMed

    Wang, Hui; Huang, Quan; Chang, Hong; Xiao, Jianru; Cheng, Yiyun

    2016-03-01

    Dendrimers have shown great promise as carriers in drug delivery due to their unique structures and superior properties. However, the precise control of payload release from a dendrimer matrix still presents a great challenge. Stimuli-responsive dendrimers that release payloads in response to a specific trigger could offer distinct clinical advantages over those dendrimers that release payloads passively. These smart polymers are designed to specifically release their payloads at targeted regions or at constant release profiles for specific therapies. They represent an attractive alternative to targeted dendrimers and enable dendrimer-based therapeutics to be more effective, more convenient, and much safer. The wide range of stimuli, either endogenous (acid, enzyme, and redox potentials) or exogenous (light, ultrasound, and temperature change), allows great flexibility in the design of stimuli-responsive dendrimers. In this review article, we will highlight recent advances and opportunities in the development of stimuli-responsive dendrimers for the treatment of various diseases, with emphasis on cancer. Specifically, the applications of stimuli-responsive dendrimers in drug delivery as well as their mechanisms are intensively reviewed. PMID:26806314

  3. Pairwise polymer blends for oral drug delivery.

    PubMed

    Marks, Joyann A; Wegiel, Lindsay A; Taylor, Lynne S; Edgar, Kevin J

    2014-09-01

    Blends of polymers with complementary properties hold promise for addressing the diverse, demanding polymer performance requirements in amorphous solid dispersions (ASDs), but we lack comprehensive property understanding for blends of important ASD polymers. Herein, we prepare pairwise blends of commercially available polymers polyvinylpyrrolidone (PVP), the cationic acrylate copolymer Eudragit 100 (E100), hydroxypropyl methylcellulose acetate succinate (HPMCAS), carboxymethyl cellulose acetate butyrate (CMCAB), hydroxypropyl methylcellulose (HPMC), and the new derivative cellulose acetate adipate propionate (CAAdP). This study identifies miscible binary blends that may find use, for example, in ASDs for solubility and bioavailability enhancement of poorly water-soluble drugs. Differential scanning calorimetry, FTIR spectroscopy, and film clarity were used to determine blend miscibility. Several polymer combinations including HPMCAS/PVP, HPMC/CMCAB, and PVP/HPMC appear to be miscible in all proportions. In contrast, blends of E100/PVP and E100/HPMC showed a miscibility gap. Combinations of water-soluble and hydrophobic polymers like these may permit effective balancing of ASD performance criteria such as release rate and polymer-drug interaction to prevent nucleation and crystal growth of poorly soluble drugs. Miscible polymer combinations described herein will enable further study of their drug delivery capabilities, and provide a potentially valuable set of ASD formulation tools. PMID:24823790

  4. Development and characterization of metal oxide nanoparticles for the delivery of anticancer drug.

    PubMed

    Sharma, Harshita; Kumar, Krishan; Choudhary, Chetan; Mishra, Pawan K; Vaidya, Bhuvaneshwar

    2016-01-01

    The aim of the study was to prepare chemotherapeutic agent-loaded zinc oxide nanoparticles for the intracellular delivery of drug, for better therapeutic activity. Zinc oxide nanoparticles have inherent anticancer properties, hence it was envisaged that by loading the anticancer drug into zinc oxide nanoparticles, enhanced anticancer activity might be observed. Zinc oxide nanoparticles were prepared using zinc nitrate and sodium hydroxide. Starch was used as the stabilizing agent. The nanoparticles prepared were characterized for size, shape, entrapment efficiency, and drug release. Further, cell line studies were performed to evaluate cellular uptake and cytotoxicity profile using MCF-7 cells. A hemolysis study was performed to check the acute toxicity of the nanoparticles. The nanoparticles were found to be 476.4 ± 2.51 nm in size, with low PDI (0.312 ± 0.02) and high entrapment efficiency (> 85%). The nanoparticles were stable, and did not form aggregates on storage in the dispersed form. A cytotoxicity study demonstrated that drug-loaded zinc oxide nanoparticles exhibited higher anticancer activity as compared to either blank zinc oxide nanoparticles and doxorubicin (DOX) alone, or their mixture. A hemolytic test revealed that the prepared zinc oxide nanoparticles caused negligible hemolysis. Thus, it can be concluded that zinc oxide nanoparticles loaded with DOX resulted in better uptake of the chemotherapeutic agent, and at the same time, showed low toxicity towards normal cells. PMID:25406734

  5. Towards more effective advanced drug delivery systems.

    PubMed

    Crommelin, Daan J A; Florence, Alexander T

    2013-09-15

    This position paper discusses progress made and to be made with so-called advanced drug delivery systems, particularly but not exclusively those in the nanometre domain. The paper has resulted from discussions with a number of international experts in the field who shared their views on aspects of the subject, from the nomenclature used for such systems, the sometimes overwrought claims made in the era of nanotechnology, the complex nature of targeting delivery systems to specific destinations in vivo, the need for setting standards for the choice and characterisation of cell lines used in in vitro studies, to attention to the manufacturability, stability and analytical profiling of systems and more relevant studies on toxicology. The historical background to the development of many systems is emphasised. So too is the stochastic nature of many of the steps to successful access to and action in targets. A lacuna in the field is the lack of availability of data on a variety of carrier systems using the same models in vitro and in vivo using standard controls. The paper asserts that greater emphasis must also be paid to the effective levels of active attained in target organs, for without such crucial data it will be difficult for many experimental systems to enter the clinic. This means the use of diagnostic/imaging technologies to monitor targeted drug delivery and stratify patient groups, identifying patients with optimum chances for successful therapy. Last, but not least, the critical importance of the development of science bases for regulatory policies, scientific platforms overseeing the field and new paradigms of financing are discussed. PMID:23415662

  6. Recent advances in polymeric micelles for anti-cancer drug delivery.

    PubMed

    Biswas, Swati; Kumari, Preeti; Lakhani, Prit Manish; Ghosh, Balaram

    2016-02-15

    Block co-polymeric micelles receive increased attention due to their ability to load therapeutics, deliver the cargo to the site of action, improve the pharmacokinetic of the loaded drug and reduce off-target cytotoxicity. While polymeric micelles can be developed with improved drug loading capabilities by modulating hydrophobicity and hydrophilicity of the micelle forming block co-polymers, they can also be successfully cancer targeted by surface modifying with tumor-homing ligands. However, maintenance of the integrity of the self-assembled system in the circulation and disassembly for drug release at the site of drug action remain a challenge. Therefore, stimuli-responsive polymeric micelles for on demand drug delivery with minimal off-target effect has been developed and extensively investigated to assess their sensitivity. This review focuses on discussing various polymeric micelles currently utilized for the delivery of chemotherapeutic drugs. Designs of various stimuli-sensitive micelles that are able to control drug release in response to specific stimuli, either endogenous or exogenous have been delineated. PMID:26747018

  7. Getting into the brain: approaches to enhance brain drug delivery.

    PubMed

    Patel, Mayur M; Goyal, Bhoomika R; Bhadada, Shraddha V; Bhatt, Jay S; Amin, Avani F

    2009-01-01

    Being the most delicate organ of the body, the brain is protected against potentially toxic substances by the blood-brain barrier (BBB), which restricts the entry of most pharmaceuticals into the brain. The developmental process for new drugs for the treatment of CNS disorders has not kept pace with progress in molecular neurosciences because most of the new drugs discovered are unable to cross the BBB. The clinical failure of CNS drug delivery may be attributed largely to a lack of appropriate drug delivery systems. Localized and controlled delivery of drugs at their desired site of action is preferred because it reduces toxicity and increases treatment efficiency. The present review provides an insight into some of the recent advances made in the field of brain drug delivery.The various strategies that have been explored to increase drug delivery into the brain include (i) chemical delivery systems, such as lipid-mediated transport, the prodrug approach and the lock-in system; (ii) biological delivery systems, in which pharmaceuticals are re-engineered to cross the BBB via specific endogenous transporters localized within the brain capillary endothelium; (iii) disruption of the BBB, for example by modification of tight junctions, which causes a controlled and transient increase in the permeability of brain capillaries; (iv) the use of molecular Trojan horses, such as peptidomimetic monoclonal antibodies to transport large molecules (e.g. antibodies, recombinant proteins, nonviral gene medicines or RNA interference drugs) across the BBB; and (v) particulate drug carrier systems. Receptor-mediated transport systems exist for certain endogenous peptides, such as insulin and transferrin, enabling these molecules to cross the BBB in vivo.The use of polymers for local drug delivery has greatly expanded the spectrum of drugs available for the treatment of brain diseases, such as malignant tumours and Alzheimer's disease. In addition, various drug delivery systems (e

  8. [Research on intelligent controlled drug delivery with polymer].

    PubMed

    Zhang, Zhibin; Tang, Changwei; Chen, Huiqing; Shan, Lianhai; Wan, Changxiu

    2006-02-01

    The intelligent controlled drug delivery systems are a series of the preparations including microcapsules or nanocapsules composed of intelligent polymers and medication. The properties of preparations can change with the external stimuli such as pH value, temperature, chemical substance, light, electricity and magnetism. According to this properties, the drug delivery can be intelligently controlled. This paper has reviewed research on syntheses and applications of intelligent controlled drug delivery systems with polymers. PMID:16532842

  9. Intrathecal Drug Delivery (ITDD) systems for cancer pain

    PubMed Central

    Bhatia, Gaurav; Lau, Mary E; Koury, Katharine M; Gulur, Padma

    2014-01-01

    Intrathecal drug delivery is an effective pain management option for patients with chronic and cancer pain. The delivery of drugs into the intrathecal space provides superior analgesia with smaller doses of analgesics to minimize side effects while significantly improving quality of life. This article aims to provide a general overview of the use of intrathecal drug delivery to manage pain, dosing recommendations, potential risks and complications, and growing trends in the field. PMID:24555051

  10. Spatiotemporally synchronized cancer combination therapy using photo-activated nanoparticle drug delivery systems (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Hasan, Tayyaba

    2016-03-01

    This talk will introduce a new nanotechnology platform for cancer combination therapy that utilizes near infrared light activation not only for photodynamic damage but also as an extrinsic mechanism to initiate release of complimentary drugs to suppress dynamic bursts in molecular signaling networks that promote tumor cell survival and treatment escape. The goal is to achieve co-delivery with concomitant activity of photodynamic, molecular inhibitor and chemotherapeutic agents, selectively within the tumor. This approach overcomes challenges in achieving synergistic interactions using sequential drug delivery. Conventional drug delivery is compromised by the differential pharmacokinetics of individual agents and potentially antagonistic effects—such as vascular shutdown by one agent that limits delivery of the second. Here, photodynamic damage—which efficiently kills drug-resistant cells via damage of common proteins involved in drug-resistance (such as anti-apoptosis factors and drug-efflux transporters)—is synchronized spatially and temporally with the photo-initiated release of complimentary agents—to enable full interaction amongst the individual therapies. This spatiotemporal synchronization offers new prospects for exploiting time-sensitive synergistic interactions. Specific implementations of these concepts will be presented in preclinical models of cancer. Strategies to enable molecular-targeting of cancer cells via site-specific attachment of targeting moieties to the outer lipid shell of these nanovehicles will also be discussed. If successful in humans, this new paradigm for synchronized, tumor-focused combination therapy will ultimately supersede the present use of chronic drug injection by increasing efficacy per cycle whilst reducing systemic exposure to toxic drugs.

  11. Recent approaches for reducing hemolytic activity of chemotherapeutic agents.

    PubMed

    Jeswani, Gunjan; Alexander, Amit; Saraf, Shailendra; Saraf, Swarnlata; Qureshi, Azra; Ajazuddin

    2015-08-10

    Drug induced hemolysis is a frequent complication associated with chemotherapy. It results from interaction of drug with erythrocyte membrane and leads to cell lysis. In recent past, various approaches were made to reduce drug-induced hemolysis, which includes drug polymer conjugation, drug delivery via colloidal carriers and hydrogels, co-administration of botanical agents and modification in molecular chemistry of drug molecules. The basic concept behind these strategies is to protect the red blood cells from membrane damaging effects of drugs. There are several examples of drug polymer conjugate that either are approved by Food and Drug Administration or are under clinical trial for delivering drugs with reduced toxicities. Likewise, colloidal carriers are also used successfully nowadays for the delivery of various chemotherapeutic agents like gemcitabine and amphotericin B with remarkable decrease in their hemolytic activity. Similarly, co-administration of botanical agents with drugs works as secondary system proving protection and strength to erythrocyte membranes. In addition to the above statement, interaction hindrance between RBC and drug molecule by molecular modification plays an important role in reducing hemolysis. This review predominantly describes the above recent approaches explored to achieve the reduced hemolytic activity of drugs especially chemotherapeutic agents. PMID:26047758

  12. Lipoidal Soft Hybrid Biocarriers of Supramolecular Construction for Drug Delivery

    PubMed Central

    Kumar, Dinesh; Sharma, Deepak; Singh, Gurmeet; Singh, Mankaran; Rathore, Mahendra Singh

    2012-01-01

    Lipid-based innovations have achieved new heights during the last few years as an essential component of drug development. The current challenge of drug delivery is liberation of drug agents at the right time in a safe and reproducible manner to a specific target site. A number of novel drug delivery systems has emerged encompassing various routes of administration, to achieve controlled and targeted drug delivery. Microparticulate lipoidal vesicular system represents a unique technology platform suitable for the oral and systemic administration of a wide variety of molecules with important therapeutic biological activities, including drugs, genes, and vaccine antigens. The success of liposomes as drug carriers has been reflected in a number of liposome-based formulations, which are commercially available or are currently undergoing clinical trials. Also, novel lipid carrier-mediated vesicular systems are originated. This paper has focused on the lipid-based supramolecular vesicular carriers that are used in various drug delivery and drug targeting systems. PMID:22888455

  13. Local arterial wall drug delivery using balloon catheter system.

    PubMed

    Tesfamariam, Belay

    2016-09-28

    Balloon-based drug delivery systems allow localized application of drugs to a vascular segment to reduce neointimal hyperplasia and restenosis. Drugs are coated onto balloons using excipients as drug carriers to facilitate adherence and release of drug during balloon inflation. Drug-coated balloon delivery system is characterized by a rapid drug transfer that achieves high drug concentration along the vessel wall surface, intended to correspond to the balloon dilation-induced vascular injury and healing processes. The balloon catheter system allows homogenous drug delivery to the vessel wall, such that the drug release per unit surface area is kept constant along balloons of different lengths. Optimization of the balloon coating matrix is essential for efficient drug transfer and tissue retention until the artery remodels to a normal set point. Challenges in the development of balloon-based drug delivery to the arterial wall include finding suitable excipients for drug formulation to enable drug release to a targeted lesion site effectively, maintain coating integrity during transit, prolong tissue retention and reduce particulate generation. This review highlights various factors involved in the successful design of balloon-based delivery systems, including drug release kinetics, matrix coating transfer, transmural drug partitioning, dissolution rate and release of unbound active drug. PMID:27473765

  14. Polymeric carriers: role of geometry in drug delivery

    PubMed Central

    Simone, Eric A; Dziubla, Thomas D; Muzykantov, Vladimir R

    2009-01-01

    The unique properties of synthetic nanostructures promise a diverse set of applications as carriers for drug delivery, which are advantageous in terms of biocompatibility, pharmacokinetics, targeting and controlled drug release. Historically, more traditional drug delivery systems have focused on spherical carriers. However, there is a growing interest in pursuing non-spherical carriers, such as elongated or filamentous morphologies, now available due to novel formulation strategies. Unique physiochemical properties of these supramolecular structures offer distinct advantages as drug delivery systems. In particular, results of recent studies in cell cultures and lab animals indicate that rational design of carriers of a given geometry (size and shape) offers an unprecedented control of their longevity in circulation and targeting to selected cellular and subcellular locations. This article reviews drug delivery aspects of non-spherical drug delivery systems, including material selection and formulation, drug loading and release, biocompatibility, circulation behavior, targeting and subcellular addressing. PMID:19040392

  15. Engineering bioceramic microstructure for customized drug delivery

    NASA Astrophysics Data System (ADS)

    Pacheco Gomez, Hernando Jose

    One of the most efficient approaches to treat cancer and infection is to use biomaterials as a drug delivery system (DDS). The goal is for the material to provide a sustained release of therapeutic drug dose locally to target the ill tissue without affecting other organs. Silica Calcium Phosphate nano composite (SCPC) is a drug delivery platform that successfully demonstrated the ability to bind and release several therapeutics including antibiotics, anticancer drugs, and growth factors. The aim of the present work is to analyze the role of SCPC microstructure on drug binding and release kinetics. The main crystalline phases of SCPC are alpha-cristobalite (SiO2, Cris) and beta-rhenanite (NaCaPO4, Rhe); therefore, these two phases were prepared and characterized separately. Structural and compositional features of Cris, Rhe and SCPC bioceramics demonstrated a significant influence on the loading capacity and release kinetics profile of Vancomycin (Vanc) and Cisplatin (Cis). Fourier Transform Infrared (FTIR) spectroscopy analyses demonstrated that the P-O functional group in Rhe and SCPC has high affinity to the (C=O and N-H) of Vanc and (N-H and O-H) of Cis. By contrast, a weak chemical interaction between the Si-O functional group in Cris and SCPC and the two drugs was observed. Vanc loading per unit surface area increased in the order 8.00 microg Vanc/m2 for Rhe > 4.49 microg Vanc /m2 for SCPC>3.01 microg Vanc /m2 for Cris (p<0.05). Cis loading capacity increased in the order 8.59 microg Vanc /m2 for Cris, 17.8 microg Vanc/m2 for Rhe and 6.03 microg Vanc /m2 for SCPC (p<0.05). Drug release kinetics was dependent on the carrier as well as on the kind of drug. Different burst release and sustained release rates were measured for Vanc and Cis from the same carrier. The percentages of drug amount released from Cris, Rhe and SCPC during the burst stage (the first 2h) were: 50%, 50%, and 46% of Vanc; and 53.4%, 36.6%, and 30.6 % of Cis, respectively. Burst release was

  16. The Controlled Drug Delivery Systems: Past Forward and Future Back

    PubMed Central

    Park, Kinam

    2014-01-01

    The controlled drug delivery technology has progressed over the last six decades. It began in 1952 with the introduction of the first sustained release formulation. The 1st generation (1950-1980) of drug delivery was focused on developing oral and transdermal sustained release systems and establishing the controlled drug release mechanisms. Attention of the 2nd generation (1980-2010) was dedicated to development of zero-order release systems, self-regulated drug delivery systems, long-term depot formulations, and nanotechnology-based delivery systems. The latter part of the 2nd generation was consumed mostly for studying nanoparticle formulations. The Journal of Controlled Release (JCR) has played a pivotal role during the 2nd generation of drug delivery technologies, and it will continue playing a leading role for the next generation. Taking the right path towards the productive 3rd generation of drug delivery technologies requires honest open dialogues without any preconceived ideas of the past. The drug delivery field needs to take a bold approach of designing the future drug delivery formulations first, based on today’s necessities, and produce necessary innovations. The JCR will provide the forum for sharing the new ideas that will shape the 3rd generation of drug delivery technologies. PMID:24794901

  17. Microencapsulation: A promising technique for controlled drug delivery

    PubMed Central

    Singh, M.N.; Hemant, K.S.Y.; Ram, M.; Shivakumar, H.G.

    2010-01-01

    Microparticles offer various significant advantages as drug delivery systems, including: (i) an effective protection of the encapsulated active agent against (e.g. enzymatic) degradation, (ii) the possibility to accurately control the release rate of the incorporated drug over periods of hours to months, (iii) an easy administration (compared to alternative parenteral controlled release dosage forms, such as macro-sized implants), and (iv) Desired, pre-programmed drug release profiles can be provided which match the therapeutic needs of the patient. This article gives an overview on the general aspects and recent advances in drug-loaded microparticles to improve the efficiency of various medical treatments. An appropriately designed controlled release drug delivery system can be a foot ahead towards solving problems concerning to the targeting of drug to a specific organ or tissue, and controlling the rate of drug delivery to the target site. The development of oral controlled release systems has been a challenge to formulation scientist due to their inability to restrain and localize the system at targeted areas of gastrointestinal tract. Microparticulate drug delivery systems are an interesting and promising option when developing an oral controlled release system. The objective of this paper is to take a closer look at microparticles as drug delivery devices for increasing efficiency of drug delivery, improving the release profile and drug targeting. In order to appreciate the application possibilities of microcapsules in drug delivery, some fundamental aspects are briefly reviewed. PMID:21589795

  18. Engineering bioceramic microstructure for customized drug delivery

    NASA Astrophysics Data System (ADS)

    Pacheco Gomez, Hernando Jose

    One of the most efficient approaches to treat cancer and infection is to use biomaterials as a drug delivery system (DDS). The goal is for the material to provide a sustained release of therapeutic drug dose locally to target the ill tissue without affecting other organs. Silica Calcium Phosphate nano composite (SCPC) is a drug delivery platform that successfully demonstrated the ability to bind and release several therapeutics including antibiotics, anticancer drugs, and growth factors. The aim of the present work is to analyze the role of SCPC microstructure on drug binding and release kinetics. The main crystalline phases of SCPC are alpha-cristobalite (SiO2, Cris) and beta-rhenanite (NaCaPO4, Rhe); therefore, these two phases were prepared and characterized separately. Structural and compositional features of Cris, Rhe and SCPC bioceramics demonstrated a significant influence on the loading capacity and release kinetics profile of Vancomycin (Vanc) and Cisplatin (Cis). Fourier Transform Infrared (FTIR) spectroscopy analyses demonstrated that the P-O functional group in Rhe and SCPC has high affinity to the (C=O and N-H) of Vanc and (N-H and O-H) of Cis. By contrast, a weak chemical interaction between the Si-O functional group in Cris and SCPC and the two drugs was observed. Vanc loading per unit surface area increased in the order 8.00 microg Vanc/m2 for Rhe > 4.49 microg Vanc /m2 for SCPC>3.01 microg Vanc /m2 for Cris (p<0.05). Cis loading capacity increased in the order 8.59 microg Vanc /m2 for Cris, 17.8 microg Vanc/m2 for Rhe and 6.03 microg Vanc /m2 for SCPC (p<0.05). Drug release kinetics was dependent on the carrier as well as on the kind of drug. Different burst release and sustained release rates were measured for Vanc and Cis from the same carrier. The percentages of drug amount released from Cris, Rhe and SCPC during the burst stage (the first 2h) were: 50%, 50%, and 46% of Vanc; and 53.4%, 36.6%, and 30.6 % of Cis, respectively. Burst release was

  19. Advances in Lymphatic Imaging and Drug Delivery

    SciTech Connect

    Nune, Satish K.; Gunda, Padmaja; Majeti, Bharat K.; Thallapally, Praveen K.; Laird, Forrest M.

    2011-09-10

    Cancer remains the second leading cause of death after heart disease in the US. While metastasized cancers such as breast, prostate, and colon are incurable, before their distant spread, these diseases will have invaded the lymphatic system as a first step in their progression. Hence, proper evaluation of the disease state of the lymphatics which drain a tumor site is crucial to staging and the formation of a treatment plan. Current lymphatic imaging modalities with visible dyes and radionucleotide tracers offer limited sensitivity and poor resolution; however, newer tools using nanocarriers, quantum dots, and magnetic resonance imaging promise to vastly improve the staging of lymphatic spread without needless biopsies. Concurrent with the improvement of lymphatic imaging agents, has been the development of drug carriers that can localize chemotherapy to the lymphatic system, thus improving the treatment of localized disease while minimizing the exposure of healthy organs to cytotoxic drugs. This review will focus on polymeric systems that have been developed for imaging and drug delivery to the lymph system, how these new devices improve upon current technologies, and where further improvement is needed.

  20. Bioinspired Nanonetworks for Targeted Cancer Drug Delivery.

    PubMed

    Raz, Nasibeh Rady; Akbarzadeh-T, Mohammad-R; Tafaghodi, Mohsen

    2015-12-01

    A biomimicry approach to nanonetworks is proposed here for targeted cancer drug delivery (TDD). The swarm of bioinspired nanomachines utilizes the blood distribution network and chemotaxis to carry drug through the vascular system to the cancer site, recognized by a high concentration of vascular endothelial growth factor (VEGF). Our approach is multi-scale and includes processes that occur both within cells and with their neighbors. The proposed bionanonetwork takes advantage of several organic processes, some of which already occur within the human body, such as a plate-like structure similar to those of red blood cells for more environmental contact; a berry fruit architecture for its internal multi-foams architecture; the penetrable structure of cancer cells, tissue, as well as the porous structure of the capillaries for drug penetration; state of glycocalyx for ligand-receptor adhesion; as well as changes in pH state of blood and O 2 release for nanomachine communication. For a more appropriate evaluation, we compare our work with a conventional chemotherapy approach using a mathematical model of cancer under actual experimental parameter settings. Simulation results show the merits of the proposed method in targeted cancer therapy by improving the densities of the relevant cancer cell types and VEGF concentration, while following more organic and natural processes. PMID:26529771

  1. Polymeric Microgels as Potential Drug Delivery Vesicles

    NASA Astrophysics Data System (ADS)

    McDonough, Ryan; Streletzky, Kiril; Bayachou, Mekki; Peiris, Pubudu

    2010-03-01

    The temperature dependent volume phase change of cross-linked amphiphilic molecules (microgels) suggests their use as drug delivery vesicles. Drug particles aggregate in the slightly hydrophobic microgel interior. They are stored in equilibrium until the critical temperature (Tv) is reached where the volume phase change limits available space, thus expelling the drugs. This loading property of hydroxypropylcellulose (HPC) microgels was tested using amperometric analytical techniques. Small molecules inside microgels do not approach the electrode surface, which decreases current signal. A room temperature (Troom) flow amperometric measurement comparing microgel/paracetamol solution with control paracetamol samples yielded about 20 percent concentration reduction in the microgel sample. Results from the steady-state electrochemical experiment confirm the 20 percent concentration drop in the microgel sample compared to the control sample at Troom. Using the steady-state experiment with a cyclic temperature ramp from Troom to beyond Tv showed that the paracetamol concentration change between the temperature extremes was greater for the microgels than for the controls. An evolving aspect of the study is the characterization of microgel shrinkage from in situ, temperature controlled liquid AFM images as compared to previously completed DLS characterization of the same microgel sample.

  2. Nanomicellar formulations for sustained drug delivery: strategies and underlying principles

    PubMed Central

    Trivedi, Ruchit; Kompella, Uday B

    2010-01-01

    Micellar delivery systems smaller than 100 nm can be readily prepared. While micelles allow a great depth of tissue penetration for targeted drug delivery, they usually disintegrate rapidly in the body. Thus, sustained drug delivery from micellar nanocarriers is a challenge. This article summarizes various key strategies and underlying principles for sustained drug delivery using micellar nanocarriers. Comparisons are made with other competing delivery systems such as polymeric microparticles and nanoparticles. Amphiphilic molecules self-assemble in appropriate liquid media to form nanoscale micelles. Strategies for sustained release nanomicellar carriers include use of prodrugs, drug polymer conjugates, novel polymers with low critical micellar concentration or of a reverse thermoresponsive nature, reverse micelles, multi-layer micelles with layer by layer assembly, polymeric films capable of forming micelles in vivo and micelle coats on a solid support. These new micellar systems are promising for sustained drug delivery. PMID:20394539

  3. Approaches to Neural Tissue Engineering Using Scaffolds for Drug Delivery

    PubMed Central

    Willerth, Stephanie M.; Sakiyama-Elbert, Shelly E.

    2007-01-01

    This review seeks to give an overview of the current approaches to drug delivery from scaffolds for neural tissue engineering applications. The challenges presented by attempting to replicate the three types of nervous tissue (brain, spinal cord, and peripheral nerve) are summarized. Potential scaffold materials (both synthetic and natural) and target drugs are discussed with the benefits and drawbacks given. Finally, common methods of drug delivery, including degradable/diffusion-based delivery systems, affinity-based delivery systems, immobilized drug delivery systems, and electrically controlled drug delivery systems, are examined and critiqued. Based on the current body of work, suggestions for future directions of research in the field of neural tissue engineering are presented. PMID:17482308

  4. Drug delivery by organ-specific immunoliposomes

    SciTech Connect

    Maruyama, Kazuo; Mori, Atsuhide; Hunag, Leaf . Dept. of Biochemistry); Kennel, S.J. )

    1990-01-01

    Monoclonal antibodies highly specific to the mouse pulmonary endothelial cells were conjugated to liposomes. The resulting immunoliposomes showed high levels of lung accumulation when injected intravenously into mice. Optimal target binding and retention were achieved if the lipid composition included ganglioside GM{sub 1} to reduce the uptake of immunoliposomes by the reticuloendothelial system. Details of the construction and optimization of these organ-specific immunoliposomes are reviewed. The drug delivery potential of this novel liposome system was demonstrated in an experimental pulmonary metastasis model. Immunoliposomes containing a lipophilic prodrug of deoxyfluorouridine effectively prolonged the survival time of the tumor-bearing mice. This and other therapeutic applications of the immunoliposomes are discussed. 25 refs., 5 figs.

  5. Ocular Drug Delivery for Glaucoma Management

    PubMed Central

    Gooch, Nathan; Molokhia, Sarah A.; Condie, Russell; Burr, Randon Michael; Archer, Bonnie; Ambati, Balamurali K.; Wirostko, Barbara

    2012-01-01

    Current glaucoma management modalities are hindered by low patient compliance and adherence. This can be due to highly complex treatment strategies or poor patient understanding. Treatments focus on the management or reduction of intraocular pressure. This is most commonly done through the use of daily topical eye drops. Unfortunately, despite effective therapies, glaucoma continues to progress, possibly due to patients not adhering to their treatments. In order to mitigate these patient compliance issues, many sustained release treatments are being researched and are entering the clinic. Conjunctival, subconjunctival, and intravitreal inserts, punctal plugs, and drug depots are currently in clinical development. Each delivery system has hurdles, yet shows promise and could potentially mitigate the current problems associated with poor patient compliance. PMID:24300188

  6. Enzyme-Responsive Nanomaterials for Controlled Drug Delivery

    PubMed Central

    Hu, Quanyin; Katti, Prateek S.; Gu, Zhen

    2015-01-01

    Enzymes underpin physiological function and exhibit dysregulation in many disease-associated microenvironments and aberrant cell processes. Exploiting altered enzyme activity and expression for diagnostics, drug targeting, and drug release is tremendously promising. When combined with booming research in nanobiotechnology, enzyme-responsive nanomaterials for controlled drug release have achieved significant development and been studied as an important class of drug delivery devices in nanomedicine. In this review, we describe enzymes such as proteases, phospholipase and oxidoreductases that serve as delivery triggers. Subsequently, we explore recently developed enzyme-responsive nanomaterials with versatile applications for extracellular and intracellular drug delivery. We conclude by discussing future opportunities and challenges in this area. PMID:25251024

  7. Enzyme-responsive nanomaterials for controlled drug delivery

    NASA Astrophysics Data System (ADS)

    Hu, Quanyin; Katti, Prateek S.; Gu, Zhen

    2014-10-01

    Enzymes underpin physiological function and exhibit dysregulation in many disease-associated microenvironments and aberrant cell processes. Exploiting altered enzyme activity and expression for diagnostics, drug targeting, and drug release is tremendously promising. When combined with booming research in nanobiotechnology, enzyme-responsive nanomaterials used for controlled drug release have achieved significant development and have been studied as an important class of drug delivery strategies in nanomedicine. In this review, we describe enzymes such as proteases, phospholipases and oxidoreductases that serve as delivery triggers. Subsequently, we explore recently developed enzyme-responsive nanomaterials with versatile applications for extracellular and intracellular drug delivery. We conclude by discussing future opportunities and challenges in this area.

  8. Dual targeting of integrin αvβ3 and matrix metalloproteinase-2 for optical imaging of tumors and chemotherapeutic delivery

    PubMed Central

    Crisp, Jessica L.; Savariar, Elamprakash N.; Glasgow, Heather L.; Ellies, Lesley G.; Whitney, Michael A.; Tsien, Roger. Y.

    2014-01-01

    Activatable cell penetrating peptides (ACPPs) provide a general strategy for molecular targeting by exploiting the extracellular protease activities associated with disease. Previous work used a matrix metalloproteinase (MMP-2 and 9) cleavable sequence in the ACPP to target contrast agents for tumor imaging and fluorescence guided surgery. To improve specificity and sensitivity for MMP-2, an integrin αvβ3 binding domain, cyclic-RGD, was covalently linked to the ACPP. This co-targeting strategy relies on the interaction of MMP-2 with integrin αvβ3, which are known to associate via MMP-2’s hemopexin domain. In U87MG glioblastoma cells in culture, dual targeting greatly improved ACPP uptake compared to either MMP or integrin αvβ3 targeting alone. In vivo, dual-targeted ACPP treatment resulted in tumor contrast of 7.8±1.6, a 10 fold higher tumor fluorescence compared to the negative control peptide, and increased probe penetration into the core of MDA-MB-231 tumors. This platform also significantly improved efficacy of the chemotherapeutic monomethylauristatin E (MMAE) in both MDA-MB-231 orthotopic human and syngeneic Py230 murine breast tumors. Treatment with cyclic-RGD-PLGC(Me)AG-MMAE-ACPP resulted in complete tumor regression in one quarter of MDA-MB-231 tumor bearing mice, compared to no survival in the control groups. This rational mechanism for amplified delivery of imaging and potent chemotherapeutic agents avoids the use of antibodies and may be of considerable generality. PMID:24737028

  9. Pharmacological Drug Delivery Strategies for Improved Therapeutic Effects: Recent Advances.

    PubMed

    Savaliya, Reema; Singh, Poornima; Singh, Sanjay

    2016-01-01

    The latest pharmacologic research has resulted number of new molecules with the potential to modernize the prevention or treatment of different complex diseases, including cancer. The therapeutics generally include moieties such as proteins, drugs and genes, etc. Current activities in the pharmacological field include the development of novel drug-delivery systems to overcome pharmacokinetic glitches such as limited bioavailability, unwanted distribution, drug resistant, and stability, etc. Therefore, to address these issues various biotechnological and pharmacological techniques has been introduced. However, effective drug delivery with improved efficacy remains challenging. This review is focused towards different strategies such as physical and biological methods for efficacious delivery at desired tissues and even sub-cellular targeting. Emphasis is also given about nanotechnology based drug or gene delivery strategies and co-delivery of drug-drug; gene-gene or combinations of drug-gene, etc. are the current cuttingedge methods, which are under clinical or pre-clinical stage of research. Uses of biodegradable materials, such as liposomes and polymeric particles are another class of drug delivery vehicles, which have shown tremendous success, are also discussed. Towards the end, future directions of pharmacological drug delivery methods have also been summarized. PMID:26654439

  10. Peptides as targeting probes against tumor vasculature for diagnosis and drug delivery

    PubMed Central

    2012-01-01

    Tumor vasculature expresses a distinct set of molecule signatures on the endothelial cell surface different from the resting blood vessels of other organs and tissues in the body. This makes them an attractive target for cancer therapy and molecular imaging. The current technology using the in vivo phage display biopanning allows us to quickly isolate and identify peptides potentially homing to various tumor blood vessels. Tumor-homing peptides in conjugation with chemotherapeutic drugs or imaging contrast have been extensively tested in various preclinical and clinical studies. These tumor-homing peptides have valuable potential as targeting probes for tumor molecular imaging and drug delivery. In this review, we summarize the recent advances about the applications of tumor-homing peptides selected by in vivo phage display library screening against tumor vasculature. We also introduce the characteristics of the latest discovered tumor-penetrating peptides in their potential clinical applications. PMID:23046982

  11. Paclitaxel-loaded phosphonated calixarene nanovesicles as a modular drug delivery platform

    PubMed Central

    Mo, Jingxin; Eggers, Paul K.; Yuan, Zhi-xiang; Raston, Colin L.; Lim, Lee Yong

    2016-01-01

    A modular p-phosphonated calix[4]arene vesicle (PCV) loaded with paclitaxel (PTX) and conjugated with folic acid as a cancer targeting ligand has been prepared using a thin film-sonication method. It has a pH-responsive capacity to trigger the release of the encapsulated PTX payload under mildly acidic conditions. PTX-loaded PCV conjugated with alkyne-modified PEG-folic acid ligands prepared via click ligation (fP-PCVPTX) has enhanced potency against folate receptor (FR)-positive SKOV-3 ovarian tumour cells over FR-negative A549 lung tumour cells. Moreover, fP-PCVPTX is also four times more potent than the non-targeting PCVPTX platform towards SKOV-3 cells. Overall, as a delivery platform the PCVs have the potential to enhance efficacy of anticancer drugs by targeting a chemotherapeutic payload specifically to tumours and triggering the release of the encapsulated drug in the vicinity of cancer cells. PMID:27009430

  12. Mitochondrial biology, targets, and drug delivery.

    PubMed

    Milane, Lara; Trivedi, Malav; Singh, Amit; Talekar, Meghna; Amiji, Mansoor

    2015-06-10

    In recent years, mitochondrial medicine has emerged as a new discipline resting at the intersection of mitochondrial biology, pathology, and pharmaceutics. The central role of mitochondria in critical cellular processes such as metabolism and apoptosis has placed mitochondria at the forefront of cell science. Advances in mitochondrial biology have revealed that these organelles continually undergo fusion and fission while functioning independently and in complex cellular networks, establishing direct membrane contacts with each other and with other organelles. Understanding the diverse cellular functions of mitochondria has contributed to understanding mitochondrial dysfunction in disease states. Polyplasmy and heteroplasmy contribute to mitochondrial phenotypes and associated dysfunction. Residing at the center of cell biology, cellular functions, and disease pathology and being laden with receptors and targets, mitochondria are beacons for pharmaceutical modification. This review presents the current state of mitochondrial medicine with a focus on mitochondrial function, dysfunction, and common disease; mitochondrial receptors, targets, and substrates; and mitochondrial drug design and drug delivery with a focus on the application of nanotechnology to mitochondrial medicine. Mitochondrial medicine is at the precipice of clinical translation; the objective of this review is to aid in the advancement of mitochondrial medicine from infancy to application. PMID:25841699

  13. Detection and drug delivery from superhydrophobic materials

    NASA Astrophysics Data System (ADS)

    Falde, Eric John

    The wetting of a rough material is controlled by surface chemistry and morphology, the liquid phase, solutes, and surfactants that affect the surface tension with the gas phase, and environmental conditions such as temperature and pressure. Materials with high (>150°) apparent contact angles are known as superhydrophobic and are very resistant to wetting. However, in complex biological mixtures eventually protein adsorbs, fouling the surface and facilitating wetting on time scales from seconds to months. The work here uses the partially-wetted (Cassie-Baxter) to fully-wetted (Wenzel) state transition to control drug delivery and to perform surfactant detection via surface tension using hydrophobic and superhydrophobic materials. First there is an overview of the physics of the non-wetting state and the transition to wetting. Then there is a review of how wetting can be controlled by outside stimuli and applications of these materials. Next there is work presented on controlling drug release using superhydrophobic materials with controlled wetting rates, with both in vitro and in vivo results. Then there is work on developing a sensor based on this wetting state transition and its applications toward detecting solute levels in biological fluids for point-of-care diagnosis. Finally, there is work presented on using these sensors for detecting the alcohol content in wine and spirits.

  14. Oral Drug Delivery with Polymeric Nanoparticles: The Gastrointestinal Mucus Barriers

    PubMed Central

    Ensign, Laura M.; Cone, Richard; Hanes, Justin

    2012-01-01

    Oral delivery is the most common method for drug administration. However, poor solubility, stability, and bioavailability of many drugs make achieving therapeutic levels via the gastrointestinal (GI) tract challenging. Drug delivery must overcome numerous hurdles, including the acidic gastric environment and the continuous secretion of mucus that protects the GI tract. Nanoparticle drug carriers that can shield drugs from degradation and deliver them to intended sites within the GI tract may enable more efficient and sustained drug delivery. However, the rapid secretion and shedding of GI tract mucus can significantly limit the effectiveness of nanoparticle drug delivery systems. Many types of nanoparticles are efficiently trapped in and rapidly removed by mucus, making controlled release in the GI tract difficult. This review addresses the protective barrier properties of mucus secretions, how mucus affects the fate of orally administered nanoparticles, and recent developments in nanoparticles engineered to penetrate the mucus barrier. PMID:22212900

  15. Nanoparticle-based drug delivery to the vagina: a review

    PubMed Central

    Ensign, Laura M.; Cone, Richard; Hanes, Justin

    2014-01-01

    Vaginal drug administration can improve prophylaxis and treatment of many conditions affecting the female reproductive tract, including sexually transmitted diseases, fungal and bacterial infections, and cancer. However, achieving sustained local drug concentrations in the vagina can be challenging, due to the high permeability of the vaginal epithelium and expulsion of conventional soluble drug dosage forms. Nanoparticle-based drug delivery platforms have received considerable attention for vaginal drug delivery, as nanoparticles can provide sustained release, cellular targeting, and even intrinsic antimicrobial or adjuvant properties that can improve the potency and/or efficacy of prophylactic and therapeutic modalities. Here, we review the use of polymeric nanoparticles, liposomes, dendrimers, and inorganic nanoparticles for vaginal drug delivery. Although most of the work toward nanoparticle-based drug delivery in the vagina has been focused on HIV prevention, strategies for treatment and prevention of other sexually transmitted infections, treatment for reproductive tract cancer, and treatment of fungal and bacterial infections are also highlighted. PMID:24830303

  16. Synthetic Tumor Networks for Screening Drug Delivery Systems

    PubMed Central

    Prabhakarpandian, Balabhaskar; Shen, Ming-Che; Nichols, Joseph B.; Garson, Charles J.; Mills, Ivy R.; Matar, Majed M.; Fewell, Jason G.; Pant, Kapil

    2015-01-01

    Tumor drug delivery is a complex phenomenon affected by several elements in addition to drug or delivery vehicle’s physico-chemical properties. A key factor is tumor microvasculature with complex effects including convective transport, high interstitial pressure and enhanced vascular permeability due to the presence of “leaky vessels”. Current in vitro models of the tumor microenvironment for evaluating drug delivery are oversimplified and, as a result, show poor correlation with in vivo performance. In this study, we report on the development of a novel microfluidic platform that models the tumor microenvironment more accurately, with physiologically and morphologically realistic microvasculature including endothelial cell lined leaky capillary vessels along with 3D solid tumors. Endothelial cells and 3D spheroids of cervical tumor cells were co-cultured in the networks. Drug vehicle screening was demonstrated using GFP gene delivery by different formulations of nanopolymers. The synthetic tumor network was successful in predicting in vivo delivery efficiencies of the drug vehicles. The developed assay will have critical applications both in basic research, where it can be used to develop next generation delivery vehicles, and in drug discovery where it can be used to study drug transport and delivery efficacy in realistic tumor microenvironment, thereby enabling drug compound and/or delivery vehicle screening. PMID:25599856

  17. Nano- and microfabrication for overcoming drug delivery challenges

    PubMed Central

    Kam, Kimberly R.

    2013-01-01

    This highlight article describes current nano- and microfabrication techniques for creating drug delivery devices. We first review the main physiological barriers to delivering therapeutic agents. Then, we describe how novel fabrication methods can be utilized to combine many features into a single physiologically relevant device to overcome drug delivery challenges. PMID:23730504

  18. Hydrogels for ocular drug delivery and tissue engineering

    PubMed Central

    Fathi, Marzieh; Barar, Jaleh; Aghanejad, Ayuob; Omidi, Yadollah

    2015-01-01

    Hydrogels, as crosslinked polymeric three dimensional networks, possess unique structure and behavior in response to the internal and/or external stimuli. As a result, they offer great prospective applications in drug delivery, cell therapy and human tissue engineering. Here, we highlight the potential of hydrogels in prolonged intraocular drug delivery and ocular surface therapy using stem cells incorporated hydrogels. PMID:26929918

  19. Perspectives on the Interface of Drug Delivery and Tissue Engineering

    PubMed Central

    Ekenseair, Adam K.; Kasper, F. Kurtis; Mikos, Antonios G.

    2012-01-01

    Controlled drug delivery of bioactive molecules continues to be an essential component of engineering strategies for tissue defect repair. This article surveys the current challenges associated with trying to regenerate complex tissues utilizing drug delivery and gives perspectives on the development of translational tissue engineering therapies which promote spatiotemporal cell-signaling cascades to maximize the rate and quality of repair. PMID:23000743

  20. Synthetic tumor networks for screening drug delivery systems.

    PubMed

    Prabhakarpandian, Balabhaskar; Shen, Ming-Che; Nichols, Joseph B; Garson, Charles J; Mills, Ivy R; Matar, Majed M; Fewell, Jason G; Pant, Kapil

    2015-03-10

    Tumor drug delivery is a complex phenomenon affected by several elements in addition to drug or delivery vehicle's physico-chemical properties. A key factor is tumor microvasculature with complex effects including convective transport, high interstitial pressure and enhanced vascular permeability due to the presence of "leaky vessels". Current in vitro models of the tumor microenvironment for evaluating drug delivery are oversimplified and, as a result, show poor correlation with in vivo performance. In this study, we report on the development of a novel microfluidic platform that models the tumor microenvironment more accurately, with physiologically and morphologically realistic microvasculature including endothelial cell lined leaky capillary vessels along with 3D solid tumors. Endothelial cells and 3D spheroids of cervical tumor cells were co-cultured in the networks. Drug vehicle screening was demonstrated using GFP gene delivery by different formulations of nanopolymers. The synthetic tumor network was successful in predicting in vivo delivery efficiencies of the drug vehicles. The developed assay will have critical applications both in basic research, where it can be used to develop next generation delivery vehicles, and in drug discovery where it can be used to study drug transport and delivery efficacy in realistic tumor microenvironment, thereby enabling drug compound and/or delivery vehicle screening. PMID:25599856

  1. Mesoporous Fe{sub 3}O{sub 4}/hydroxyapatite composite for targeted drug delivery

    SciTech Connect

    Gu, Lina; He, Xiaomei; Wu, Zhenyu

    2014-11-15

    Highlights: • Mesoporous Fe{sub 3}O{sub 4}/hydroxyapatite composite was synthesized by a simple, efficient and environmental friendly method. • The prepared material had a large surface area, high pore volume, and good magnetic separability. • DOX-loaded Fe{sub 3}O{sub 4}/hydroxyapatite composite exhibited surprising slow drug release behavior and pH-dependent behavior. - Abstract: In this contribution, we introduced a simple, efficient, and green method of preparing a mesoporous Fe{sub 3}O{sub 4}/hydroxyapatite (HA) composite. The as-prepared material had a large surface area, high pore volume, and good magnetic separability, which made it suitable for targeted drug delivery systems. The chemotherapeutic agent doxorubicin (DOX) was used to investigate the drug release behavior of Fe{sub 3}O{sub 4}/HA composite. The drug release profiles displayed a little burst effect and pH-dependent behavior. The release rate of DOX at pH 5.8 was larger than that at pH 7.4, which could be attributed to DOX protonation in acid medium. In addition, the released DOX concentrations remained at 0.83 and 1.39 μg/ml at pH 7.4 and 5.8, respectively, which indicated slow, steady, and safe release rates. Therefore, the as-prepared Fe{sub 3}O{sub 4}/hydroxyapatite composite could be an efficient platform for targeted anticancer drug delivery.

  2. Safe and Immunocompatible Nanocarriers Cloaked in RBC Membranes for Drug Delivery to Treat Solid Tumors

    PubMed Central

    Luk, Brian T.; Fang, Ronnie H.; Hu, Che-Ming J.; Copp, Jonathan A.; Thamphiwatana, Soracha; Dehaini, Diana; Gao, Weiwei; Zhang, Kang; Li, Shulin; Zhang, Liangfang

    2016-01-01

    The therapeutic potential of nanoparticle-based drug carriers depends largely on their ability to evade the host immune system while delivering their cargo safely to the site of action. Of particular interest are simple strategies for the functionalization of nanoparticle surfaces that are both inherently safe and can also bestow immunoevasive properties, allowing for extended blood circulation times. Here, we evaluated a recently reported cell membrane-coated nanoparticle platform as a drug delivery vehicle for the treatment of a murine model of lymphoma. These biomimetic nanoparticles, consisting of a biodegradable polymeric material cloaked with natural red blood cell membrane, were shown to efficiently deliver a model chemotherapeutic, doxorubicin, to solid tumor sites for significantly increased tumor growth inhibition compared with conventional free drug treatment. Importantly, the nanoparticles also showed excellent immunocompatibility as well as an advantageous safety profile compared with the free drug, making them attractive for potential translation. This study demonstrates the promise of using a biomembrane-coating approach as the basis for the design of functional, safe, and immunocompatible nanocarriers for cancer drug delivery. PMID:27217833

  3. Safe and Immunocompatible Nanocarriers Cloaked in RBC Membranes for Drug Delivery to Treat Solid Tumors.

    PubMed

    Luk, Brian T; Fang, Ronnie H; Hu, Che-Ming J; Copp, Jonathan A; Thamphiwatana, Soracha; Dehaini, Diana; Gao, Weiwei; Zhang, Kang; Li, Shulin; Zhang, Liangfang

    2016-01-01

    The therapeutic potential of nanoparticle-based drug carriers depends largely on their ability to evade the host immune system while delivering their cargo safely to the site of action. Of particular interest are simple strategies for the functionalization of nanoparticle surfaces that are both inherently safe and can also bestow immunoevasive properties, allowing for extended blood circulation times. Here, we evaluated a recently reported cell membrane-coated nanoparticle platform as a drug delivery vehicle for the treatment of a murine model of lymphoma. These biomimetic nanoparticles, consisting of a biodegradable polymeric material cloaked with natural red blood cell membrane, were shown to efficiently deliver a model chemotherapeutic, doxorubicin, to solid tumor sites for significantly increased tumor growth inhibition compared with conventional free drug treatment. Importantly, the nanoparticles also showed excellent immunocompatibility as well as an advantageous safety profile compared with the free drug, making them attractive for potential translation. This study demonstrates the promise of using a biomembrane-coating approach as the basis for the design of functional, safe, and immunocompatible nanocarriers for cancer drug delivery. PMID:27217833

  4. Nanoscale covalent organic frameworks as smart carriers for drug delivery.

    PubMed

    Bai, Linyi; Phua, Soo Zeng Fiona; Lim, Wei Qi; Jana, Avijit; Luo, Zhong; Tham, Huijun Phoebe; Zhao, Lingzhi; Gao, Qiang; Zhao, Yanli

    2016-03-18

    Two porous covalent organic frameworks (COFs) with good biocompatibility were employed as drug nanocarriers, where three different drugs were loaded for subsequent drug release in vitro. The present work demonstrates that COFs are applicable in drug delivery for therapeutic applications. PMID:26877025

  5. ZEB1 knockdown mediated using polypeptide cationic micelles inhibits metastasis and effects sensitization to a chemotherapeutic drug for cancer therapy

    NASA Astrophysics Data System (ADS)

    Fang, Shengtao; Wu, Lei; Li, Mingxing; Yi, Huqiang; Gao, Guanhui; Sheng, Zonghai; Gong, Ping; Ma, Yifan; Cai, Lintao

    2014-08-01

    Metastasis and drug resistance are the main causes for the failure in clinical cancer therapy. Emerging evidence suggests an intricate role of epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs) in metastasis and drug resistance. The EMT-activator ZEB1 is crucial in malignant tumor progression by linking EMT-activation and stemness-maintenance. Here, we used multifunctional polypeptide micelle nanoparticles (NP) as nanocarriers for the delivery of ZEB1 siRNA and doxorubicin (DOX). The nanocarriers could effectively deliver siRNA to the cytoplasm and knockdown the target gene in H460 cells and H460 xenograft tumors, leading to reduced EMT and repressed CSC properties in vitro and in vivo. The complex micelle nanoparticles with ZEB1 siRNA (siRNA-NP) significantly reduced metastasis in the lung. When DOX and siRNA were co-delivered by the nanocarriers (siRNA-DOX-NP), a synergistic therapeutic effect was observed, resulting in dramatic inhibition of tumor growth in a H460 xenograft model. These results demonstrated that the siRNA-NP or siRNA-DOX-NP complex targeting ZEB1 could be developed into a new therapeutic approach for non-small cell lung cancer (NSCLC) treatment.Metastasis and drug resistance are the main causes for the failure in clinical cancer therapy. Emerging evidence suggests an intricate role of epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs) in metastasis and drug resistance. The EMT-activator ZEB1 is crucial in malignant tumor progression by linking EMT-activation and stemness-maintenance. Here, we used multifunctional polypeptide micelle nanoparticles (NP) as nanocarriers for the delivery of ZEB1 siRNA and doxorubicin (DOX). The nanocarriers could effectively deliver siRNA to the cytoplasm and knockdown the target gene in H460 cells and H460 xenograft tumors, leading to reduced EMT and repressed CSC properties in vitro and in vivo. The complex micelle nanoparticles with ZEB1 siRNA (siRNA-NP) significantly reduced

  6. Pharmacosomes: An Emerging Novel Vesicular Drug Delivery System for Poorly Soluble Synthetic and Herbal Drugs

    PubMed Central

    2013-01-01

    In the arena of solubility enhancement, several problems are encountered. A novel approach based on lipid drug delivery system has evolved, pharmacosomes. Pharmacosomes are colloidal, nanometric size micelles, vesicles or may be in the form of hexagonal assembly of colloidal drug dispersions attached covalently to the phospholipid. They act as befitting carrier for delivery of drugs quite precisely owing to their unique properties like small size, amphiphilicity, active drug loading, high entrapment efficiency, and stability. They help in controlled release of drug at the site of action as well as in reduction in cost of therapy, drug leakage and toxicity, increased bioavailability of poorly soluble drugs, and restorative effects. There has been advancement in the scope of this delivery system for a number of drugs used for inflammation, heart diseases, cancer, and protein delivery along with a large number of herbal drugs. Hence, pharmacosomes open new challenges and opportunities for improved novel vesicular drug delivery system. PMID:24106615

  7. Nanocrystal for ocular drug delivery: hope or hype.

    PubMed

    Sharma, Om Prakash; Patel, Viral; Mehta, Tejal

    2016-08-01

    The complexity of the structure and nature of the eye emanates a challenge for drug delivery to formulation scientists. Lower bioavailability concern of conventional ocular formulation provokes the interest of researchers in the development of novel drug delivery system. Nanotechnology-based formulations have been extensively investigated and found propitious in improving bioavailability of drugs by overcoming ocular barriers prevailing in the eye. The advent of nanocrystals helped in combating the problem of poorly soluble drugs specifically for oral and parenteral drug delivery and led to development of various marketed products. Nanocrystal-based formulations explored for ocular drug delivery have been found successful in achieving increase in retention time, bioavailability, and permeability of drugs across the corneal and conjunctival epithelium. In this review, we have highlighted the ocular physiology and barriers in drug delivery. A comparative analysis of various nanotechnology-based ocular formulations is done with their pros and cons. Consideration is also given to various methods of preparation of nanocrystals with their patented technology. This article highlights the success achieved in conquering various challenges of ocular delivery by the use of nanocrystals while emphasizing on its advantages and application for ocular formulation. The perspectives of nanocrystals as an emerging flipside to explore the frontiers of ocular drug delivery are discussed. PMID:27165145

  8. Impact and mechanism of non-steroidal anti-inflammatory drugs combined with chemotherapeutic drugs on human lung cancer-nude mouse transplanted tumors

    PubMed Central

    SUN, WEIYI; CHEN, GANG

    2016-01-01

    The present study aimed to investigate the impact of indomethacin treatment combined with oxaliplatin treatment on the expression of cluster of differentiation 44 variant 6 (CD44v6), matrix metalloproteinase-2 (MMP-2) and survivin in human lung cancer-nude mouse transplanted tumors. The human lung adenocarcinoma (A549)-nude mouse transplanted tumor model was established, and the mice were divided into a control group, an indomethacin treatment group, an oxaliplatin treatment group and an indomethacin-oxaliplatin combination treatment group. The tumor inhibition rate was calculated following sacrificing of the mice. Immunohistochemical staining and fluorescence reverse transcription-quantitative polymerase chain reaction were utilized to detect the protein and messenger (m)RNA expression of CD44v6, MMP-2 and survivin. The tumor inhibition rates of the indomethacin group, the oxaliplatin group and the combination group were 26.67, 47.70 and 68.88%, respectively. The protein and mRNA expression levels of CD44v6, MMP-2 and survivin in the transplanted tumors of each treatment group were reduced compared with the control group (P<0.05), and those of the combination group were lower compared with the single-drug treatment groups (P<0.05). Survivin and MMP-2, MMP-2 and CD44v6, and MMP-2 and CD44v6 all exhibited linear positive correlation. The present study provides evidence that the administration of indomethacin alone, or in combination with oxaliplatin, may significantly inhibit the growth of lung cancer-nude mouse transplanted tumors and the expression of CD44v6, MMP-2 and survivin inside the tumor. The combination of non-steroidal anti-inflammatory drugs with chemotherapeutic drugs may improve the antitumor effects. PMID:27313765

  9. Drug Delivery Systems and Combination Therapy by Using Vinca Alkaloids

    PubMed Central

    Lee, Chun-Ting; Huang, Yen-Wei; Yang, Chih-Hui; Huang, Keng-Shiang

    2015-01-01

    Developing new methods for chemotherapy drug delivery has become a topic of great concern. Vinca alkaloids are among the most widely used chemotherapy reagents for tumor therapy; however, their side effects are particularly problematic for many medical doctors. To reduce the toxicity and enhance the therapeutic efficiency of vinca alkaloids, many researchers have developed strategies such as using liposome-entrapped drugs, chemical- or peptide-modified drugs, polymeric packaging drugs, and chemotherapy drug combinations. This review mainly focuses on the development of a vinca alkaloid drug delivery system and the combination therapy. Five vinca alkaloids (eg, vincristine, vinblastine, vinorelbine, vindesine, and vinflunine) are reviewed. PMID:25877096

  10. Drug delivery systems and combination therapy by using vinca alkaloids.

    PubMed

    Lee, Chun-Ting; Huang, Yen-Wei; Yang, Chih-Hui; Huang, Keng-Shiang

    2015-01-01

    Developing new methods for chemotherapy drug delivery has become a topic of great concern. Vinca alkaloids are among the most widely used chemotherapy reagents for tumor therapy; however, their side effects are particularly problematic for many medical doctors. To reduce the toxicity and enhance the therapeutic efficiency of vinca alkaloids, many researchers have developed strategies such as using liposome-entrapped drugs, chemical- or peptide-modified drugs, polymeric packaging drugs, and chemotherapy drug combinations. This review mainly focuses on the development of a vinca alkaloid drug delivery system and the combination therapy. Five vinca alkaloids (eg, vincristine, vinblastine, vinorelbine, vindesine, and vinflunine) are reviewed. PMID:25877096

  11. Nanofibers based antibacterial drug design, delivery and applications.

    PubMed

    Ulubayram, Kezban; Calamak, Semih; Shahbazi, Reza; Eroglu, Ipek

    2015-01-01

    Infections caused by microorganisms like bacteria, fungi, etc. are the main obstacle in healing processes. Conventional antibacterial administration routes can be listed as oral, intravenous/intramuscular, topical and inhalation. These kinds of drug administrations are faced with critical vital issues such as; more rapid delivery of the drug than intended which can result in bacterial resistance, dose related systemic toxicity, tissue irritation and finally delayed healing process that need to be tackled. Recently, studies have been focused on new drug delivery systems, overcoming resistance and toxicological problems and finally localizing the molecules at the site of action in a proper dose. In this regard, many nanotechnological approaches such as nanoparticulate therapeutic systems have been developed to address accompanying problems mentioned above. Among them, drug loaded electrospun nanofibers propose main advantages like controlled drug delivery, high drug loading capacity, high encapsulation efficiency, simultaneous delivery of multiple drugs, ease of production and cost effectiveness for pharmaceutical and biomedical applications. Therefore, some particular attention has been devoted to the design of electrospun nanofibers as promising antibacterial drug carrier systems. A variety of antibacterials e.g., biocides, antibiotics, quaternary ammonium salts, triclosan, metallic nanoparticles (silver, titanium dioxide, and zinc oxide) and antibacterial polymers (chitosan, polyethyleneimine, etc.) have been impregnated by various techniques into nanofibers that exhibit strong antibacterial activity in standard assays. This review highlights the design and delivery of antibacterial drug loaded nanofibers with particular focus on their function in the fields of drug delivery, wound healing, tissue engineering, cosmetics and other biomedical applications. PMID:25732666

  12. Novel Approaches in Formulation and Drug Delivery using Contact Lenses

    PubMed Central

    Singh, Kishan; Nair, Anroop B; Kumar, Ashok; Kumria, Rachna

    2011-01-01

    The success of ocular delivery relies on the potential to enhance the drug bioavailability by controlled and extended release of drug on the eye surface. Several new approaches have been attempted to augment the competence and diminish the intrinsic side effects of existing ocular drug delivery systems. In this contest, progress has been made to develop drug-eluting contact lens using different techniques, which have the potential to control and sustain the delivery of drug. Further, the availability of novel polymers have facilitated and promoted the utility of contact lenses in ocular drug delivery. Several research groups have already explored the feasibility and potential of contact lens using conventional drugs for the treatment of periocular and intraocular diseases. Contact lenses formulated using modern technology exhibits high loading, controlled drug release, apposite thickness, water content, superior mechanical and optical properties as compared to commercial lenses. In general, this review discus various factors and approaches designed and explored for the successful delivery of ophthalmic drugs using contact lenses as drug delivery device PMID:24826007

  13. Microemulsion: new insights into the ocular drug delivery.

    PubMed

    Hegde, Rahul Rama; Verma, Anurag; Ghosh, Amitava

    2013-01-01

    Delivery of drugs into eyes using conventional drug delivery systems, such as solutions, is a considerable challenge to the treatment of ocular diseases. Drug loss from the ocular surface by lachrymal fluid secretion, lachrymal fluid-eye barriers, and blood-ocular barriers are main obstacles. A number of ophthalmic drug delivery carriers have been made to improve the bioavailability and to prolong the residence time of drugs applied topically onto the eye. The potential use of microemulsions as an ocular drug delivery carrier offers several favorable pharmaceutical and biopharmaceutical properties such as their excellent thermodynamic stability, phase transition to liquid-crystal state, very low surface tension, and small droplet size, which may result in improved ocular drug retention, extended duration of action, high ocular absorption, and permeation of loaded drugs. Further, both lipophilic and hydrophilic characteristics are present in microemulsions, so that the loaded drugs can diffuse passively as well get significantly partitioned in the variable lipophilic-hydrophilic corneal barrier. This review will provide an insight into previous studies on microemulsions for ocular delivery of drugs using various nonionic surfactants, cosurfactants, and associated irritation potential on the ocular surface. The reported in vivo experiments have shown a delayed effect of drug incorporated in microemulsion and an increase in the corneal permeation of the drug. PMID:23936681

  14. Facing the truth about nanotechnology in drug delivery.

    PubMed

    Park, Kinam

    2013-09-24

    Nanotechnology in drug delivery has been manifested into nanoparticles that can have unique properties both in vitro and in vivo, especially in targeted drug delivery to tumors. Numerous nanoparticle formulations have been designed and tested to great effect in small animal models, but the translation of the small animal results to clinical success has been limited. Successful translation requires revisiting the meaning of nanotechnology in drug delivery, understanding the limitations of nanoparticles, identifying the misconceptions pervasive in the field, and facing inconvenient truths. Nanoparticle approaches can have real impact in improving drug delivery by focusing on the problems at hand, such as enhancing their drug loading capacity, affinity to target cells, and spatiotemporal control of drug release. PMID:24490875

  15. NanoART, neuroAIDS and CNS drug delivery

    PubMed Central

    Nowacek, Ari; Gendelman, Howard E

    2009-01-01

    A broad range of nanomedicines is being developed to improve drug delivery for CNS disorders. The structure of the blood–brain barrier (BBB), the presence of efflux pumps and the expression of metabolic enzymes pose hurdles for drug-brain entry. Nanoformulations can circumvent the BBB to improve CNS-directed drug delivery by affecting such pumps and enzymes. Alternatively, they can be optimized to affect their size, shape, and protein and lipid coatings to facilitate drug uptake, release and ingress across the barrier. This is important as the brain is a sanctuary for a broad range of pathogens including HIV-1. Improved drug delivery to the CNS would affect pharmacokinetic and drug biodistribution properties. This article focuses on how nanotechnology can serve to improve the delivery of antiretroviral medicines, termed nanoART, across the BBB and affect the biodistribution and clinical benefit for HIV-1 disease. PMID:19572821

  16. Facing the Truth about Nanotechnology in Drug Delivery

    PubMed Central

    Park, Kinam

    2013-01-01

    Nanotechnology in drug delivery has been manifested into nanoparticles that can have unique properties both in vitro and in vivo, especially in targeted drug delivery to tumors. Numerous nanoparticle formulations have been designed and tested to great effect in small animal models, but the translation of the small animal results to clinical success has been limited. Successful translation requires revisiting the meaning of nanotechnology in drug delivery, understanding the limitations of nanoparticles, identifying the misconceptions pervasive in the field, and facing inconvenient truths. Nanoparticle approaches can have real impact in improving drug delivery by focusing on the problems at hand, such as enhancing their drug loading capacity, affinity to target cells, and spatiotemporal control of drug release. PMID:24490875

  17. Controlled Release for Local Delivery of Drugs: Barriers and Models

    PubMed Central

    Weiser, Jennifer R.; Saltzman, W. Mark

    2014-01-01

    Controlled release systems are an effective means for local drug delivery. In local drug delivery, the major goal is to supply therapeutic levels of a drug agent at a physical site in the body for a prolonged period. A second goal is to reduce systemic toxicities, by avoiding the delivery of agents to non-target tissues remote from the site. Understanding the dynamics of drug transport in the vicinity of a local drug delivery device is helpful in achieving both of these goals. Here, we provide an overview of controlled release systems for local delivery and we review mathematical models of drug transport in tissue, which describe the local penetration of drugs into tissue and illustrate the factors—such as diffusion, convection, and elimination—that control drug dispersion and its ultimate fate. This review highlights the important role of controlled release science in development of reliable methods for local delivery, as well as the barriers to accomplishing effective delivery in the brain, blood vessels, mucosal epithelia, and the skin. PMID:24801251

  18. Silk-Based Biomaterials for Sustained Drug Delivery

    PubMed Central

    Yucel, Tuna; Lovett, Michael L.; Kaplan, David L.

    2014-01-01

    Silk presents a rare combination of desirable properties for sustained drug delivery, including aqueous-based purification and processing options without chemical cross-linkers, compatibility with common sterilization methods, controllable and surface-mediated biodegradation into non-inflammatory by-products, biocompatibility, utility in drug stabilization, and robust mechanical properties. A versatile silk-based toolkit is currently available for sustained drug delivery formulations of small molecule through macromolecular drugs, with a promise to mitigate several drawbacks associated with other degradable sustained delivery technologies in the market. Silk-based formulations utilize silk’s well-defined nano- through microscale structural hierarchy, stimuli-responsive self-assembly pathways and crystal polymorphism, as well as sequence and genetic modification options towards targeted pharmaceutical outcomes. Furthermore, by manipulating the interactions between silk and drug molecules, near-zero order sustained release may be achieved through diffusion- and degradation-based release mechanisms. Because of these desirable properties, there has been increasing industrial interest in silk-based drug delivery systems currently at various stages of the developmental pipeline from pre-clinical to FDA-approved products. Here, we discuss the unique aspects of silk technology as a sustained drug delivery platform and highlight the current state of the art in silk-based drug delivery. We also offer a potential early development pathway for silk-based sustained delivery products. PMID:24910193

  19. Silk-based biomaterials for sustained drug delivery.

    PubMed

    Yucel, Tuna; Lovett, Michael L; Kaplan, David L

    2014-09-28

    Silk presents a rare combination of desirable properties for sustained drug delivery, including aqueous-based purification and processing options without chemical cross-linkers, compatibility with common sterilization methods, controllable and surface-mediated biodegradation into non-inflammatory by-products, biocompatibility, utility in drug stabilization, and robust mechanical properties. A versatile silk-based toolkit is currently available for sustained drug delivery formulations of small molecule through macromolecular drugs, with a promise to mitigate several drawbacks associated with other degradable sustained delivery technologies in the market. Silk-based formulations utilize silk's well-defined nano- through microscale structural hierarchy, stimuli-responsive self-assembly pathways and crystal polymorphism, as well as sequence and genetic modification options towards targeted pharmaceutical outcomes. Furthermore, by manipulating the interactions between silk and drug molecules, near-zero order sustained release may be achieved through diffusion- and degradation-based release mechanisms. Because of these desirable properties, there has been increasing industrial interest in silk-based drug delivery systems currently at various stages of the developmental pipeline from pre-clinical to FDA-approved products. Here, we discuss the unique aspects of silk technology as a sustained drug delivery platform and highlight the current state of the art in silk-based drug delivery. We also offer a potential early development pathway for silk-based sustained delivery products. PMID:24910193

  20. Ferrocene-Modified Phospholipid: An Innovative Precursor for Redox-Triggered Drug Delivery Vesicles Selective to Cancer Cells.

    PubMed

    Noyhouzer, Tomer; L'Homme, Chloé; Beaulieu, Isabelle; Mazurkiewicz, Stephanie; Kuss, Sabine; Kraatz, Heinz-Bernhard; Canesi, Sylvain; Mauzeroll, Janine

    2016-05-01

    Controlled payload release is one of the key elements in the creation of a reliable drug delivery system. We report the discovery of a drug delivery vessel able to transport chemotherapeutic agents to target cancer cells and selectively trigger their release using the electrochemical activity of a ferrocene-modified phospholipid. Supported by in vitro assays, the competitive advantages of this discovery are (i) the simple one step scalability of the synthetic process, (ii) the stable encapsulation of toxic drugs (doxorubicin) during transport, and (iii) the selective redox triggering of the liposomes to harness their cytotoxic payload at the cancer site. Specifically, the redox-modified giant unilamellar vesicle and liposomes were characterized using advanced methods such as scanning electrochemical microscopy (SECM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and fluorescent imaging. PMID:26987014

  1. Pressure-sensitive adhesives for transdermal drug delivery systems.

    PubMed

    Tan; Pfister

    1999-02-01

    Adhesives are a critical component in transdermal drug delivery (TDD) devices. In addition to the usual requirements of functional adhesive properties, adhesives for TDD applications must have good biocompatibility with the skin, chemical compatibility with the drug, various components of the formulation, and provide consistent, effective delivery of the drug. This review discusses the three most commonly used adhesives (polyisobutylenes, polyacrylates and silicones) in TDD devices, and provides an update on recently introduced TDD products and recent developments of new adhesives. PMID:10234208

  2. Prodrugs for transdermal drug delivery - trends and challenges.

    PubMed

    Ita, Kevin B

    2016-09-01

    Prodrugs continue to attract significant interest in the transdermal drug delivery field. These moieties can confer favorable physicochemical properties on transdermal drug delivery candidates. Alkyl chain lengthening, pegylation are some of the strategies used for prodrug synthesis. It is usually important to optimize partition coefficient, water and oil solubilities of drugs. In this review, progress made in the field of prodrugs for percutaneous penetration is highlighted and the challenges discussed. PMID:26878159

  3. Advances and Challenges of Liposome Assisted Drug Delivery

    PubMed Central

    Sercombe, Lisa; Veerati, Tejaswi; Moheimani, Fatemeh; Wu, Sherry Y.; Sood, Anil K.; Hua, Susan

    2015-01-01

    The application of liposomes to assist drug delivery has already had a major impact on many biomedical areas. They have been shown to be beneficial for stabilizing therapeutic compounds, overcoming obstacles to cellular and tissue uptake, and improving biodistribution of compounds to target sites in vivo. This enables effective delivery of encapsulated compounds to target sites while minimizing systemic toxicity. Liposomes present as an attractive delivery system due to their flexible physicochemical and biophysical properties, which allow easy manipulation to address different delivery considerations. Despite considerable research in the last 50 years and the plethora of positive results in preclinical studies, the clinical translation of liposome assisted drug delivery platforms has progressed incrementally. In this review, we will discuss the advances in liposome assisted drug delivery, biological challenges that still remain, and current clinical and experimental use of liposomes for biomedical applications. The translational obstacles of liposomal technology will also be presented. PMID:26648870

  4. Reservoir-Based Drug Delivery Systems Utilizing Microtechnology

    PubMed Central

    Stevenson, Cynthia L.; Santini, John T.; Langer, Robert

    2012-01-01

    This review covers reservoir-based drug delivery systems that incorporate microtechnology, with an emphasis on oral, dermal, and implantable systems. Key features of each technology are highlighted such as working principles, fabrication methods, dimensional constraints, and performance criteria. Reservoir-based systems include a subset of microfabricated drug delivery systems and provide unique advantages. Reservoirs, whether external to the body or implanted, provide a well-controlled environment for a drug formulation, allowing increased drug stability and prolonged delivery times. Reservoir systems have the flexibility to accommodate various delivery schemes, including zero order, pulsatile, and on demand dosing, as opposed to a standard sustained release profile. Furthermore, the development of reservoir-based systems for targeted delivery for difficult to treat applications (e.g., ocular) has resulted in potential platforms for patient therapy. PMID:22465783

  5. Polymer nanogels: a versatile nanoscopic drug delivery platform

    PubMed Central

    Chacko, Reuben T.; Ventura, Judy; Zhuang, Jiaming; Thayumanavan, S.

    2012-01-01

    In this review we put the spotlight on crosslinked polymer nanogels, a promising platform that has the characteristics of an “ideal” drug delivery vehicle. Some of the key aspects of drug delivery vehicle design like stability, response to biologically relevant stimuli, passive targeting, active targeting, toxicity and ease of synthesis are discussed. We discuss several delivery systems in this light and highlight some examples of systems, which satisfy some or all of these design requirements. In particular, we point to the advantages that crosslinked polymeric systems bring to drug delivery. We review some of the synthetic methods of nanogel synthesis and conclude with the diverse applications in drug delivery where nanogels have been fruitfully employed. PMID:22342438

  6. Ultra-small lipid-polymer hybrid nanoparticles for tumor-penetrating drug delivery

    NASA Astrophysics Data System (ADS)

    Dehaini, Diana; Fang, Ronnie H.; Luk, Brian T.; Pang, Zhiqing; Hu, Che-Ming J.; Kroll, Ashley V.; Yu, Chun Lai; Gao, Weiwei; Zhang, Liangfang

    2016-07-01

    Lipid-polymer hybrid nanoparticles, consisting of a polymeric core coated by a layer of lipids, are a class of highly scalable, biodegradable nanocarriers that have shown great promise in drug delivery applications. Here, we demonstrate the facile synthesis of ultra-small, sub-25 nm lipid-polymer hybrid nanoparticles using an adapted nanoprecipitation approach and explore their utility for targeted delivery of a model chemotherapeutic. The fabrication process is first optimized to produce a monodisperse population of particles that are stable under physiological conditions. It is shown that these ultra-small hybrid nanoparticles can be functionalized with a targeting ligand on the surface and loaded with drug inside the polymeric matrix. Further, the in vivo fate of the nanoparticles after intravenous injection is characterized by examining the blood circulation and biodistribution. In a final proof-of-concept study, targeted ultra-small hybrid nanoparticles loaded with the cancer drug docetaxel are used to treat a mouse tumor model and demonstrate improved efficacy compared to a clinically available formulation of the drug. The ability to synthesize a significantly smaller version of the established lipid-polymer hybrid platform can ultimately enhance its applicability across a wider range of applications.

  7. Hollow Pollen Shells to Enhance Drug Delivery

    PubMed Central

    Diego-Taboada, Alberto; Beckett, Stephen T.; Atkin, Stephen L.; Mackenzie, Grahame

    2014-01-01

    Pollen grain and spore shells are natural microcapsules designed to protect the genetic material of the plant from external damage. The shell is made up of two layers, the inner layer (intine), made largely of cellulose, and the outer layer (exine), composed mainly of sporopollenin. The relative proportion of each varies according to the plant species. The structure of sporopollenin has not been fully characterised but different studies suggest the presence of conjugated phenols, which provide antioxidant properties to the microcapsule and UV (ultraviolet) protection to the material inside it. These microcapsule shells have many advantageous properties, such as homogeneity in size, resilience to both alkalis and acids, and the ability to withstand temperatures up to 250 °C. These hollow microcapsules have the ability to encapsulate and release actives in a controlled manner. Their mucoadhesion to intestinal tissues may contribute to the extended contact of the sporopollenin with the intestinal mucosa leading to an increased efficiency of delivery of nutraceuticals and drugs. The hollow microcapsules can be filled with a solution of the active or active in a liquid form by simply mixing both together, and in some cases operating a vacuum. The active payload can be released in the human body depending on pressure on the microcapsule, solubility and/or pH factors. Active release can be controlled by adding a coating on the shell, or co-encapsulation with the active inside the shell. PMID:24638098

  8. Hollow pollen shells to enhance drug delivery.

    PubMed

    Diego-Taboada, Alberto; Beckett, Stephen T; Atkin, Stephen L; Mackenzie, Grahame

    2014-01-01

    Pollen grain and spore shells are natural microcapsules designed to protect the genetic material of the plant from external damage. The shell is made up of two layers, the inner layer (intine), made largely of cellulose, and the outer layer (exine), composed mainly of sporopollenin. The relative proportion of each varies according to the plant species. The structure of sporopollenin has not been fully characterised but different studies suggest the presence of conjugated phenols, which provide antioxidant properties to the microcapsule and UV (ultraviolet) protection to the material inside it. These microcapsule shells have many advantageous properties, such as homogeneity in size, resilience to both alkalis and acids, and the ability to withstand temperatures up to 250 °C. These hollow microcapsules have the ability to encapsulate and release actives in a controlled manner. Their mucoadhesion to intestinal tissues may contribute to the extended contact of the sporopollenin with the intestinal mucosa leading to an increased efficiency of delivery of nutraceuticals and drugs. The hollow microcapsules can be filled with a solution of the active or active in a liquid form by simply mixing both together, and in some cases operating a vacuum. The active payload can be released in the human body depending on pressure on the microcapsule, solubility and/or pH factors. Active release can be controlled by adding a coating on the shell, or co-encapsulation with the active inside the shell. PMID:24638098

  9. Marine Origin Polysaccharides in Drug Delivery Systems.

    PubMed

    Cardoso, Matias J; Costa, Rui R; Mano, João F

    2016-02-01

    Oceans are a vast source of natural substances. In them, we find various compounds with wide biotechnological and biomedical applicabilities. The exploitation of the sea as a renewable source of biocompounds can have a positive impact on the development of new systems and devices for biomedical applications. Marine polysaccharides are among the most abundant materials in the seas, which contributes to a decrease of the extraction costs, besides their solubility behavior in aqueous solvents and extraction media, and their interaction with other biocompounds. Polysaccharides such as alginate, carrageenan and fucoidan can be extracted from algae, whereas chitosan and hyaluronan can be obtained from animal sources. Most marine polysaccharides have important biological properties such as biocompatibility, biodegradability, and anti-inflammatory activity, as well as adhesive and antimicrobial actions. Moreover, they can be modified in order to allow processing them into various shapes and sizes and may exhibit response dependence to external stimuli, such as pH and temperature. Due to these properties, these biomaterials have been studied as raw material for the construction of carrier devices for drugs, including particles, capsules and hydrogels. The devices are designed to achieve a controlled release of therapeutic agents in an attempt to fight against serious diseases, and to be used in advanced therapies, such as gene delivery or regenerative medicine. PMID:26861358

  10. Marine Origin Polysaccharides in Drug Delivery Systems

    PubMed Central

    Cardoso, Matias J.; Costa, Rui R.; Mano, João F.

    2016-01-01

    Oceans are a vast source of natural substances. In them, we find various compounds with wide biotechnological and biomedical applicabilities. The exploitation of the sea as a renewable source of biocompounds can have a positive impact on the development of new systems and devices for biomedical applications. Marine polysaccharides are among the most abundant materials in the seas, which contributes to a decrease of the extraction costs, besides their solubility behavior in aqueous solvents and extraction media, and their interaction with other biocompounds. Polysaccharides such as alginate, carrageenan and fucoidan can be extracted from algae, whereas chitosan and hyaluronan can be obtained from animal sources. Most marine polysaccharides have important biological properties such as biocompatibility, biodegradability, and anti-inflammatory activity, as well as adhesive and antimicrobial actions. Moreover, they can be modified in order to allow processing them into various shapes and sizes and may exhibit response dependence to external stimuli, such as pH and temperature. Due to these properties, these biomaterials have been studied as raw material for the construction of carrier devices for drugs, including particles, capsules and hydrogels. The devices are designed to achieve a controlled release of therapeutic agents in an attempt to fight against serious diseases, and to be used in advanced therapies, such as gene delivery or regenerative medicine. PMID:26861358

  11. Bioavailability of phytochemicals and its enhancement by drug delivery systems

    PubMed Central

    Aqil, Farrukh; Munagala, Radha; Jeyabalan, Jeyaprakash; Vadhanam, Manicka V.

    2013-01-01

    Issues of poor oral bioavailability of cancer chemopreventives have hindered progress in cancer prevention. Novel delivery systems that modulate the pharmacokinetics of existing drugs, such as nanoparticles, cyclodextrins, niosomes, liposomes and implants, could be used to enhance the delivery of chemopreventive agents to target sites. The development of new approaches in prevention and treatment of cancer could encompass new delivery systems for approved and newly investigated compounds. In this review, we discuss some of the delivery approaches that have already made an impact by either delivering a drug to target tissue or increasing its bioavailability by many fold. PMID:23435377

  12. Design, Characterization, and Optimization of Controlled Drug Delivery System Containing Antibiotic Drug/s.

    PubMed

    Patel, Apurv; Dodiya, Hitesh; Shelate, Pragna; Shastri, Divyesh; Dave, Divyang

    2016-01-01

    The objective of this work was design, characterization, and optimization of controlled drug delivery system containing antibiotic drug/s. Osmotic drug delivery system was chosen as controlled drug delivery system. The porous osmotic pump tablets were designed using Plackett-Burman and Box-Behnken factorial design to find out the best formulation. For screening of three categories of polymers, six independent variables were chosen for Plackett-Burman design. Osmotic agent sodium chloride and microcrystalline cellulose, pore forming agent sodium lauryl sulphate and sucrose, and coating agent ethyl cellulose and cellulose acetate were chosen as independent variables. Optimization of osmotic tablets was done by Box-Behnken design by selecting three independent variables. Osmotic agent sodium chloride, pore forming agent sodium lauryl sulphate, and coating agent cellulose acetate were chosen as independent variables. The result of Plackett-Burman and Box-Behnken design and ANOVA studies revealed that osmotic agent and pore former had significant effect on the drug release up to 12 hr. The observed independent variables were found to be very close to predicted values of most satisfactory formulation which demonstrates the feasibility of the optimization procedure in successful development of porous osmotic pump tablets containing antibiotic drug/s by using sodium chloride, sodium lauryl sulphate, and cellulose acetate as key excipients. PMID:27610247

  13. Design, Characterization, and Optimization of Controlled Drug Delivery System Containing Antibiotic Drug/s

    PubMed Central

    Shelate, Pragna; Dave, Divyang

    2016-01-01

    The objective of this work was design, characterization, and optimization of controlled drug delivery system containing antibiotic drug/s. Osmotic drug delivery system was chosen as controlled drug delivery system. The porous osmotic pump tablets were designed using Plackett-Burman and Box-Behnken factorial design to find out the best formulation. For screening of three categories of polymers, six independent variables were chosen for Plackett-Burman design. Osmotic agent sodium chloride and microcrystalline cellulose, pore forming agent sodium lauryl sulphate and sucrose, and coating agent ethyl cellulose and cellulose acetate were chosen as independent variables. Optimization of osmotic tablets was done by Box-Behnken design by selecting three independent variables. Osmotic agent sodium chloride, pore forming agent sodium lauryl sulphate, and coating agent cellulose acetate were chosen as independent variables. The result of Plackett-Burman and Box-Behnken design and ANOVA studies revealed that osmotic agent and pore former had significant effect on the drug release up to 12 hr. The observed independent variables were found to be very close to predicted values of most satisfactory formulation which demonstrates the feasibility of the optimization procedure in successful development of porous osmotic pump tablets containing antibiotic drug/s by using sodium chloride, sodium lauryl sulphate, and cellulose acetate as key excipients. PMID:27610247

  14. CD44hiCD24lo mammosphere-forming cells from primary breast cancer display resistance to multiple chemotherapeutic drugs.

    PubMed

    Ji, Ping; Zhang, Yong; Wang, Shu-Jun; Ge, Hai-Liang; Zhao, Guo-Ping; Xu, Ying-Chun; Wang, Ying

    2016-06-01

    It has been widely suggested that mammosphere-forming cells from tumor cell lines or primary tumors represent the population of cancer stem cells (CSCs), which is supposed to lead to the failure of routine chemotherapy and the recurrence of the disease. However, it is still difficult to obtain CSCs from primary breast cancer for further investigation. We performed a modified culture system to generate mammosphere-forming cells derived from freshly isolated human breast cancer samples and the breast cancer cell line MCF-7. Cancer stem cell-like phenotypes such as CD44 and CD24 were measured by flow cytometry while alkaline phosphatase (AP) and mammaglobin (MGB1) expression was evaluated immunohistochemically. The expression levels of Klf4, Nanog, Oct4, Sox2 and mdr1 genes were analyzed by quantitative real‑time PCR. Resistance to chemotherapeutic drugs was detected through the apoptosis assay upon drug treatments together with the detection of drug-resistant gene mdr1. The results revealed that we successfully obtained mammosphere‑forming cells from the primary breast cancer in conditioned medium after 14 days of culture. Mammosphere-forming cells from primary breast cancer displayed a CD44hiCD24lo phenotype as well as positive AP and MGB1 reactivity. Stem cell-related genes such as Klf4, Nanog and Oct4 were detectably expressed in these cells. These cells formed tumor-like structures in the lymph nodes of nude mice, which were morphologically and histologically similar to breast cancer. Compared to the breast cancer cell line MCF-7 or mammosphere-forming cells from MCF-7 cells, the mammosphere-forming cells from the primary breast cancer exhibited resistance to three of four first-line chemotherapeutic drugs investigated through the induction of apoptosis, which was largely associated with the increased expression of drug-resistant gene mdr1 upon drug treatment. In conclusion, mammosphere-forming cells generated from the primary breast cancer exhibit CSC

  15. Layered Double Hydroxide-Based Nanocarriers for Drug Delivery

    PubMed Central

    Bi, Xue; Zhang, Hui; Dou, Liguang

    2014-01-01

    Biocompatible clay materials have attracted particular attention as the efficient drug delivery systems (DDS). In this article, we review developments in the use of layered double hydroxides (LDHs) for controlled drug release and delivery. We show how advances in the ability to synthesize intercalated structures have a significant influence on the development of new applications of these materials. We also show how modification and/or functionalization can lead to new biotechnological and biomedical applications. This review highlights the most recent progresses in research on LDH-based controlled drug delivery systems, focusing mainly on: (i) DDS with cardiovascular drugs as guests; (ii) DDS with anti-inflammatory drugs as guests; and (iii) DDS with anti-cancer drugs as guests. Finally, future prospects for LDH-based drug carriers are also discussed. PMID:24940733

  16. Colloidal drug delivery systems: current status and future directions.

    PubMed

    Garg, Tarun; Rath, Goutam; Goyal, Amit Kumar

    2015-01-01

    In this paper, we provide an overview an extensive range of colloidal drug delivery systems with special focus on vesicular and particulates systems that are being used in research or might be potentially useful as carriers systems for drug or active biomolecules or as cell carriers with application in the therapeutic field. We present some important examples of commercially available drug delivery systems with applications in research or in clinical fields. This class of systems is widely used due to excellent drug targeting, sustained and controlled release behavior, higher entrapment efficiency of drug molecules, prevention of drug hydrolysis or enzymatic degradation, and improvement of therapeutic efficacy. These characteristics help in the selection of suitable carrier systems for drug, cell, and gene delivery in different fields. PMID:25955882

  17. An efficient drug delivery vehicle for botulism countermeasure

    PubMed Central

    Zhang, Peng; Ray, Radharaman; Singh, Bal Ram; Li, Dan; Adler, Michael; Ray, Prabhati

    2009-01-01

    Background Botulinum neurotoxin (BoNT) is the most potent poison known to mankind. Currently no antidote is available to rescue poisoned synapses. An effective medical countermeasure strategy would require developing a drug that could rescue poisoned neuromuscular synapses and include its efficient delivery specifically to poisoned presynaptic nerve terminals. Here we report a drug delivery strategy that could directly deliver toxin inhibitors into the intoxicated nerve terminal cytosol. Results A targeted delivery vehicle was developed for intracellular transport of emerging botulinum neurotoxin antagonists. The drug delivery vehicle consisted of the non-toxic recombinant heavy chain of botulinum neurotoxin-A coupled to a 10-kDa amino dextran via the heterobifunctional linker 3-(2-pyridylthio)-propionyl hydrazide. The heavy chain served to target botulinum neurotoxin-sensitive cells and promote internalization of the complex, while the dextran served as a platform to deliver model therapeutic molecules to the targeted neurons. Our results indicated that the drug delivery vehicle entry into neurons was via BoNT-A receptor mediated endocytosis. Once internalized into neurons, the drug carrier component separated from the drug delivery vehicle in a fashion similar to the separation of the BoNT-A light chain from the holotoxin. This drug delivery vehicle could be used to deliver BoNT-A antidotes into BoNT-A intoxicated cultured mouse spinal cord cells. Conclusion An effective BoNT-based drug delivery vehicle can be used to directly deliver toxin inhibitors into intoxicated nerve terminal cytosol. This approach can potentially be utilized for targeted drug delivery to treat other neuronal and neuromuscular disorders. This report also provides new knowledge of endocytosis and exocytosis as well as of BoNT trafficking. PMID:19860869

  18. Niosomes: a controlled and novel drug delivery system.

    PubMed

    Rajera, Rampal; Nagpal, Kalpana; Singh, Shailendra Kumar; Mishra, Dina Nath

    2011-01-01

    During the past decade formulation of vesicles as a tool to improve drug delivery, has created a lot of interest amongst the scientist working in the area of drug delivery systems. Vesicular system such as liposomes, niosomes, transferosomes, pharmacosomes and ethosomes provide an alternative to improve the drug delivery. Niosomes play an important role owing to their nonionic properties, in such drug delivery system. Design and development of novel drug delivery system (NDDS) has two prerequisites. First, it should deliver the drug in accordance with a predetermined rate and second it should release therapeutically effective amount of drug at the site of action. Conventional dosage forms are unable to meet these requisites. Niosomes are essentially non-ionic surfactant based multilamellar or unilamellar vesicles in which an aqueous solution of solute is entirely enclosed by a membrane resulting from the organization of surfactant macromolecules as bilayer. Niosomes are formed on hydration of non-ionic surfactant film which eventually hydrates imbibing or encapsulating the hydrating aqueous solution. The main aim of development of niosomes is to control the release of drug in a sustained way, modification of distribution profile of drug and for targeting the drug to the specific body site. This paper deals with composition, characterization/evaluation, merits, demerits and applications of niosomes. PMID:21719996

  19. Recent expansions in an emergent novel drug delivery technology: Emulgel.

    PubMed

    Ajazuddin; Alexander, Amit; Khichariya, Ajita; Gupta, Saurabh; Patel, Ravish J; Giri, Tapan Kumar; Tripathi, Dulal Krishna

    2013-10-28

    Emulgel is an emerging topical drug delivery system to which if more effort is paid towards its formulation & development with more number of topically effective drugs it will prove a boon for derma care & cosmetology. Emulgels are either emulsion of oil in water or water in oil type, which is gelled by mixing it with gelling agent. Incorporation of emulsion into gel increases its stability & makes it a dual control release system. Due to lack of excess oily bases & insoluble excipients, it shows better drug release as compared to other topical drug delivery system. Presence of gel phase makes it a non greasy & favors good patient compliance. These reviews give knowledge about Emulgel including its properties, advantages, formulation considerations, and its recent advances in research field. All factors such as selection of gelling agent, oil agent, emulsifiers influencing the stability and efficacy of Emulgel are discussed. All justifications are described in accordance with the research work carried out by various scientists. These brief reviews on formulation method have been included. Current research works that carried out on Emulgel are also discussed and highlighted the wide utility of Emulgel in topical drug delivery system. After the vast study, it can be concluded that the Emulgels appear better & effective drug delivery system as compared to other topical drug delivery system. The comprehensive analysis of rheological and release properties will provide an insight into the potential usage of Emulgel formulation as drug delivery system. PMID:23831051

  20. Dendrimeric systems and their applications in ocular drug delivery.

    PubMed

    Yavuz, Burçin; Pehlivan, Sibel Bozdağ; Unlü, Nurşen

    2013-01-01

    Ophthalmic drug delivery is one of the most attractive and challenging research area for pharmaceutical scientists and ophthalmologists. Absorption of an ophthalmic drug in conventional dosage forms is seriously limited by physiological conditions. The use of nonionic or ionic biodegradable polymers in aqueous solutions and colloidal dosage forms such as liposomes, nanoparticles, nanocapsules, microspheres, microcapsules, microemulsions, and dendrimers has been studied to overcome the problems mentioned above. Dendrimers are a new class of polymeric materials. The unique nanostructured architecture of dendrimers has been studied to examine their role in delivery of therapeutics and imaging agents. Dendrimers can enhance drug's water solubility, bioavailability, and biocompatibility and can be applied for different routes of drug administration successfully. Permeability enhancer properties of dendrimers were also reported. The use of dendrimers can also reduce toxicity versus activity and following an appropriate application route they allow the delivery of the drug to the targeted site and provide desired pharmacokinetic parameters. Therefore, dendrimeric drug delivery systems are of interest in ocular drug delivery. In this review, the limitations related to eye's unique structure, the advantages of dendrimers, and the potential applications of dendrimeric systems to ophthalmology including imaging, drug, peptide, and gene delivery will be discussed. PMID:24396306

  1. Dendrimeric Systems and Their Applications in Ocular Drug Delivery

    PubMed Central

    Yavuz, Burçin; Bozdağ Pehlivan, Sibel; Ünlü, Nurşen

    2013-01-01

    Ophthalmic drug delivery is one of the most attractive and challenging research area for pharmaceutical scientists and ophthalmologists. Absorption of an ophthalmic drug in conventional dosage forms is seriously limited by physiological conditions. The use of nonionic or ionic biodegradable polymers in aqueous solutions and colloidal dosage forms such as liposomes, nanoparticles, nanocapsules, microspheres, microcapsules, microemulsions, and dendrimers has been studied to overcome the problems mentioned above. Dendrimers are a new class of polymeric materials. The unique nanostructured architecture of dendrimers has been studied to examine their role in delivery of therapeutics and imaging agents. Dendrimers can enhance drug's water solubility, bioavailability, and biocompatibility and can be applied for different routes of drug administration successfully. Permeability enhancer properties of dendrimers were also reported. The use of dendrimers can also reduce toxicity versus activity and following an appropriate application route they allow the delivery of the drug to the targeted site and provide desired pharmacokinetic parameters. Therefore, dendrimeric drug delivery systems are of interest in ocular drug delivery. In this review, the limitations related to eye's unique structure, the advantages of dendrimers, and the potential applications of dendrimeric systems to ophthalmology including imaging, drug, peptide, and gene delivery will be discussed. PMID:24396306

  2. Chondroitin sulfate derived theranostic nanoparticles for targeted drug delivery.

    PubMed

    Varghese, Oommen P; Liu, Jianping; Sundaram, Karthi; Hilborn, Jöns; Oommen, Oommen P

    2016-08-16

    Glycosaminoglycan derived nanoparticles are a promising delivery system owing to their unique tumour targeting ability. Exploiting fluorescein for inducing amphiphilicity in these biopolymers provides inherent imaging and drug stabilization capabilities by π-π stacking interactions with aromatic antineoplastic agents. This offers a versatile and highly customizable nanocarrier with narrow size distribution and high drug loading efficiency (80%) with sustained drug release. PMID:27431007

  3. A Controlled Drug-Delivery Experiment Using Alginate Beads

    ERIC Educational Resources Information Center

    Farrell, Stephanie; Vernengo, Jennifer

    2012-01-01

    This paper describes a simple, cost-effective experiment which introduces students to drug delivery and modeling using alginate beads. Students produce calcium alginate beads loaded with drug and measure the rate of release from the beads for systems having different stir rates, geometries, extents of cross-linking, and drug molecular weight.…

  4. Inorganic Nanoporous Membranes for Immunoisolated Cell-Based Drug Delivery

    PubMed Central

    Mendelsohn, Adam; Desai, Tejal

    2014-01-01

    Materials advances enabled by nanotechnology have brought about promising approaches to improve the encapsulation mechanism for immunoisolated cell-based drug delivery. Cell-based drug delivery is a promising treatment for many diseases but has thus far achieved only limited clinical success. Treatment of insulin dependent diabetes mellitus (IDDM) by transplantation of pancreatic β-cells represents the most anticipated application of cell-based drug delivery technology. This review outlines the challenges involved with maintaining transplanted cell viability and discusses how inorganic nanoporous membranes may be useful in achieving clinical success. PMID:20384222

  5. Cyclodextrin nanoassemblies: a promising tool for drug delivery.

    PubMed

    Bonnet, Véronique; Gervaise, Cédric; Djedaïni-Pilard, Florence; Furlan, Aurélien; Sarazin, Catherine

    2015-09-01

    Among the biodegradable and nontoxic compounds that can form nanoparticles for drug delivery, amphiphilic cyclodextrins are very promising. Apart from ionic cyclodextrins, which have been extensively studied and reviewed because of their application in gene delivery, our purpose is to provide a clear description of the supramolecular assemblies of nonionic amphiphilic cyclodextrins, which can form nanoassemblies for controlled drug release. Moreover, we focus on the relationship between their structure and physicochemical characteristics, which is crucial for self assembly and drug delivery. We also highlight the importance of the nanoparticle technology preparation for the stability and application of this nanodevice. PMID:26037681

  6. Auto-associative amphiphilic polysaccharides as drug delivery systems.

    PubMed

    Hassani, Leila N; Hendra, Frédéric; Bouchemal, Kawthar

    2012-06-01

    Self-assembly of amphiphilic polysaccharides provides a positive outlook for drug delivery systems without the need for solvents or surfactants. Various polymeric amphiphilic polysaccharides undergo intramolecular or intermolecular associations in water. This type of association, promoted by hydrophobic segments, led to the formation of various drug delivery systems such as micelles, nanoparticles, liposomes and hydrogels. Here, we review a selection of the most important amphiphilic polysaccharides used as drug delivery systems and their pharmaceutical applications. Attention focuses on amphiphilic chitosan owing to its unique properties such as excellent biocompatibility, non-toxicity and antimicrobial and bioadhesive properties. PMID:22305936

  7. Recent advances in gastric floating drug delivery technology: a review.

    PubMed

    Pahwa, Rakesh; Bisht, Seema; Kumar, Vipin; Kohli, Kanchan

    2013-06-01

    Gastric floating drug delivery systems have been an avenue of considerable interest in terms of their immense potential for better pharmacotherapeutic interventions along with site-specific absorption. These buoyant systems significantly enhance the bioavailability and controlled delivery of several drug molecules. Scientific investigators have also carried out substantial research endeavours worldwide in order to design a more systematic and intellectual floating systems. The present manuscript is an attempt to highlight numerous recent advancements in the design of gastric floating drug delivery systems along with various available commercial preparations. Salient applications, characterization aspects and future perspectives of these multifarious systems have also been addressed. PMID:23808593

  8. Porous silicon advances in drug delivery and immunotherapy

    PubMed Central

    Savage, D; Liu, X; Curley, S; Ferrari, M; Serda, RE

    2013-01-01

    Biomedical applications of porous silicon include drug delivery, imaging, diagnostics and immunotherapy. This review summarizes new silicon particle fabrication techniques, dynamics of cellular transport, advances in the multistage vector approach to drug delivery, and the use of porous silicon as immune adjuvants. Recent findings support superior therapeutic efficacy of the multistage vector approach over single particle drug delivery systems in mouse models of ovarian and breast cancer. With respect to vaccine development, multivalent presentation of pathogen-associated molecular patterns on the particle surface creates powerful platforms for immunotherapy, with the porous matrix able to carry both antigens and immune modulators. PMID:23845260

  9. Anthracycline Nano-Delivery Systems to Overcome Multiple Drug Resistance: A Comprehensive Review

    PubMed Central

    Ma, Ping; Mumper, Russell J.

    2013-01-01

    Anthracyclines (doxorubicin, daunorubicin, and idarubicin) are very effective chemotherapeutic drugs to treat many cancers; however, the development of multiple drug resistance (MDR) is one of the major limitations for their clinical applications. Nano-delivery systems have emerged as the novel cancer therapeutics to overcome MDR. Up until now, many anthracycline nano-delivery systems have been developed and reported to effectively circumvent MDR both in-vitro and in-vivo, and some of these systems have even advanced to clinical trials, such as the HPMA-doxorubicin (HPMA-DOX) conjugate. Doxil, a DOX PEGylated liposome formulation, was developed and approved by FDA in 1995. Unfortunately, this formulation does not address the MDR problem. In this comprehensive review, more than ten types of developed anthracycline nano-delivery systems to overcome MDR and their proposed mechanisms are covered and discussed, including liposomes; polymeric micelles, conjugate and nanoparticles; peptide/protein conjugates; solid-lipid, magnetic, gold, silica, and cyclodextrin nanoparticles; and carbon nanotubes. PMID:23888183

  10. Smart multifunctional drug delivery towards anticancer therapy harmonized in mesoporous nanoparticles

    NASA Astrophysics Data System (ADS)

    Baek, Seonmi; Singh, Rajendra K.; Khanal, Dipesh; Patel, Kapil D.; Lee, Eun-Jung; Leong, Kam W.; Chrzanowski, Wojciech; Kim, Hae-Won

    2015-08-01

    Nanomedicine seeks to apply nanoscale materials for the therapy and diagnosis of diseased and damaged tissues. Recent advances in nanotechnology have made a major contribution to the development of multifunctional nanomaterials, which represents a paradigm shift from single purpose to multipurpose materials. Multifunctional nanomaterials have been proposed to enable simultaneous target imaging and on-demand delivery of therapeutic agents only to the specific site. Most advanced systems are also responsive to internal or external stimuli. This approach is particularly important for highly potent drugs (e.g. chemotherapeutics), which should be delivered in a discreet manner and interact with cells/tissues only locally. Both advances in imaging and precisely controlled and localized delivery are critically important in cancer treatment, and the use of such systems - theranostics - holds great promise to minimise side effects and boost therapeutic effectiveness of the treatment. Among others, mesoporous silica nanoparticles (MSNPs) are considered one of the most promising nanomaterials for drug delivery. Due to their unique intrinsic features, including tunable porosity and size, large surface area, structural diversity, easily modifiable chemistry and suitability for functionalization, and biocompatibility, MSNPs have been extensively utilized as multifunctional nanocarrier systems. The combination or hybridization with biomolecules, drugs, and other nanoparticles potentiated the ability of MSNPs towards multifunctionality, and even smart actions stimulated by specified signals, including pH, optical signal, redox reaction, electricity and magnetism. This paper provides a comprehensive review of the state-of-the-art of multifunctional, smart drug delivery systems centered on advanced MSNPs, with special emphasis on cancer related applications.

  11. Smart multifunctional drug delivery towards anticancer therapy harmonized in mesoporous nanoparticles.

    PubMed

    Baek, Seonmi; Singh, Rajendra K; Khanal, Dipesh; Patel, Kapil D; Lee, Eun-Jung; Leong, Kam W; Chrzanowski, Wojciech; Kim, Hae-Won

    2015-09-14

    Nanomedicine seeks to apply nanoscale materials for the therapy and diagnosis of diseased and damaged tissues. Recent advances in nanotechnology have made a major contribution to the development of multifunctional nanomaterials, which represents a paradigm shift from single purpose to multipurpose materials. Multifunctional nanomaterials have been proposed to enable simultaneous target imaging and on-demand delivery of therapeutic agents only to the specific site. Most advanced systems are also responsive to internal or external stimuli. This approach is particularly important for highly potent drugs (e.g. chemotherapeutics), which should be delivered in a discreet manner and interact with cells/tissues only locally. Both advances in imaging and precisely controlled and localized delivery are critically important in cancer treatment, and the use of such systems - theranostics - holds great promise to minimise side effects and boost therapeutic effectiveness of the treatment. Among others, mesoporous silica nanoparticles (MSNPs) are considered one of the most promising nanomaterials for drug delivery. Due to their unique intrinsic features, including tunable porosity and size, large surface area, structural diversity, easily modifiable chemistry and suitability for functionalization, and biocompatibility, MSNPs have been extensively utilized as multifunctional nanocarrier systems. The combination or hybridization with biomolecules, drugs, and other nanoparticles potentiated the ability of MSNPs towards multifunctionality, and even smart actions stimulated by specified signals, including pH, optical signal, redox reaction, electricity and magnetism. This paper provides a comprehensive review of the state-of-the-art of multifunctional, smart drug delivery systems centered on advanced MSNPs, with special emphasis on cancer related applications. PMID:26260245

  12. Multifunctional aptamer-based nanoparticles for targeted drug delivery to circumvent cancer resistance.

    PubMed

    Liu, Juan; Wei, Tuo; Zhao, Jing; Huang, Yuanyu; Deng, Hua; Kumar, Anil; Wang, Chenxuan; Liang, Zicai; Ma, Xiaowei; Liang, Xing-Jie

    2016-06-01

    By its unique advantages over traditional medicine, nanomedicine has offered new strategies for cancer treatment. In particular, the development of drug delivery strategies has focused on nanoscale particles to improve bioavailability. However, many of these nanoparticles are unable to overcome tumor resistance to chemotherapeutic agents. Recently, new opportunities for drug delivery have been provided by oligonucleotides that can self-assemble into three-dimensional nanostructures. In this work, we have designed and developed functional DNA nanostructures to deliver the chemotherapy drug doxorubicin (Dox) to resistant cancer cells. These nanostructures have two components. The first component is a DNA aptamer, which forms a dimeric G-quadruplex nanostructure to target cancer cells by binding with nucleolin. The second component is double-stranded DNA (dsDNA), which is rich in -GC- base pairs that can be applied for Dox delivery. We demonstrated that Dox was able to efficiently intercalate into dsDNA and this intercalation did not affect the aptamer's three-dimensional structure. In addition, the Aptamer-dsDNA (ApS) nanoparticle showed good stability and protected the dsDNA from degradation in bovine serum. More importantly, the ApS&Dox nanoparticle efficiently reversed the resistance of human breast cancer cells to Dox. The mechanism circumventing doxorubicin resistance by ApS&Dox nanoparticles may be predominantly by cell cycle arrest in S phase, effectively increased cell uptake and decreased cell efflux of doxorubicin. Furthermore, the ApS&Dox nanoparticles could effectively inhibit tumor growth, while less cardiotoxicity was observed. Overall, this functional DNA nanostructure provides new insights into the design of nanocarriers to overcome multidrug resistance through targeted drug delivery. PMID:26994877

  13. Ultrasound/Magnetic Targeting with SPIO-DOX-Microbubble Complex for Image-Guided Drug Delivery in Brain Tumors

    PubMed Central

    Fan, Ching-Hsiang; Cheng, Yu-Hang; Ting, Chien-Yu; Ho, Yi-Ju; Hsu, Po-Hung; Liu, Hao-Li; Yeh, Chih-Kuang

    2016-01-01

    One of the greatest challenges in the deployment of chemotherapeutic drugs against brain tumors is ensuring that sufficient drug concentrations reach the tumor, while minimizing drug accumulation at undesired sites. Recently, injection of therapeutic agents following blood-brain barrier (BBB) opening by focused ultrasound (FUS) with microbubbles (MBs) has been shown to enhance drug delivery in targeted brain regions. Nevertheless, the distribution and quantitative deposition of agents delivered to the brain are still hard to estimate. Based on our previous work on superparamagnetic iron oxide (SPIO)-loaded MBs, we present a novel theranostic complex of SPIO-Doxorubicin (DOX)-conjugated MB (SD-MB) for drug delivery to the brain. Magnetic labeling of the drug enables direct visualization via magnetic resonance imaging, and also facilitates magnetic targeting (MT) to actively enhance targeted deposition of the drug. In a rat glioma model, we demonstrated that FUS sonication can be used with SD-MBs to simultaneously facilitate BBB opening and allow dual ultrasound/magnetic targeting of chemotherapeutic agent (DOX) delivery. The accumulation of SD complex within brain tumors can be significantly enhanced by MT (25.7 fold of DOX, 7.6 fold of SPIO). The change in relaxation rate R2 (1/T2) within tumors was highly correlated with SD deposition as quantified by high performance liquid chromatography (R2 = 0.93) and inductively coupled plasma-atomic emission spectroscopy (R2 = 0.94), demonstrating real-time monitoring of DOX distribution. Our results suggest that SD-MBs can serve as multifunction agents to achieve advanced molecular theranostics. PMID:27446489

  14. Nasal Drug Delivery in Traditional Persian Medicine

    PubMed Central

    Zarshenas, Mohammad Mehdi; Zargaran, Arman; Müller, Johannes; Mohagheghzadeh, Abdolali

    2013-01-01

    Background Over one hundred different pharmaceutical dosage forms have been recorded in literatures of Traditional Persian Medicine among which nasal forms are considerable. Objectives This study designed to derive the most often applied nasal dosage forms together with those brief clinical administrations. Materials and Methods In the current study remaining pharmaceutical manuscripts of Persia during 9th to 18th century AD have been studied and different dosage forms related to nasal application of herbal medicines and their therapeutic effects were derived. Results By searching through pharmaceutical manuscripts of medieval Persia, different nasal dosage forms involving eleven types related to three main groups are found. These types could be derived from powder, solution or liquid and gaseous forms. Gaseous form were classified into fumigation (Bakhoor), vapor bath (Enkebab), inhalation (Lakhlakheh), aroma agents (Ghalieh) and olfaction or smell (Shomoom). Nasal solutions were as drops (Ghatoor), nasal snuffing drops (Saoot) and liquid snuff formulations (Noshoogh). Powders were as nasal insufflation or snorting agents (Nofookh) and errhine or sternutator medicine (Otoos). Nasal forms were not applied only for local purposes. Rather systemic disorders and specially CNS complications were said to be a target for these dosage forms. Discussion While this novel type of drug delivery is known as a suitable substitute for oral and parenteral administration, it was well accepted and extensively mentioned in Persian medical and pharmaceutical manuscripts and other traditional systems of medicine as well. Accordingly, medieval pharmaceutical standpoints on nasal dosage forms could still be an interesting subject of study. Therefore, the current work can briefly show the pharmaceutical knowledge on nasal formulations in medieval Persia and clarify a part of history of traditional Persian pharmacy. PMID:24624204

  15. Atopic Dermatitis: Drug Delivery Approaches in Disease Management.

    PubMed

    Lalan, Manisha; Baweja, Jitendra; Misra, Ambikanandan

    2015-01-01

    In this review, we describe the very basic of atopic dermatitis (AD), the established management strategies, and the advances in drug delivery approaches for successful therapeutic outcomes. The multifactorial pathophysiology of AD has given rise to the clinician's paradigm of topical and systemic therapy and potential combinations. However, incomplete remission of skin disorders like AD is a major challenge to be overcome. Recurrence is thought to be due to genetic and immunological etiologies and shortcomings in drug delivery. This difficulty has sparked research in nanocarrier-based delivery approaches as well as molecular biology-inspired stratagems to deal with the immunological imbalance and to address insufficiencies of delivery propositions. In this review, we assess various novel drug delivery strategies in terms of their success and utility. We present a brief compilation and assessment of management modalities to sensitize the readers to therapeutic scenario in AD. PMID:26080926

  16. Ultrasound-mediated drug delivery for cardiovascular disease

    PubMed Central

    Sutton, Jonathan T; Haworth, Kevin J; Pyne-Geithman, Gail; Holland, Christy K

    2014-01-01

    Introduction Ultrasound (US) has been developed as both a valuable diagnostic tool and a potent promoter of beneficial tissue bioeffects for the treatment of cardiovascular disease. These effects can be mediated by mechanical oscillations of circulating microbubbles, or US contrast agents, which may also encapsulate and shield a therapeutic agent in the bloodstream. Oscillating microbubbles can create stresses directly on nearby tissue or induce fluid effects that effect drug penetration into vascular tissue, lyse thrombi or direct drugs to optimal locations for delivery. Areas covered The present review summarizes investigations that have provided evidence for US-mediated drug delivery as a potent method to deliver therapeutics to diseased tissue for cardiovascular treatment. In particular, the focus will be on investigations of specific aspects relating to US-mediated drug delivery, such as delivery vehicles, drug transport routes, biochemical mechanisms and molecular targeting strategies. Expert opinion These investigations have spurred continued research into alternative therapeutic applications, such as bioactive gas delivery and new US technologies. Successful implementation of US-mediated drug delivery has the potential to change the way many drugs are administered systemically, resulting in more effective and economical therapeutics, and less-invasive treatments. PMID:23448121

  17. Design of Microbubbles for Gene/Drug Delivery.

    PubMed

    Bettinger, Thierry; Tranquart, François

    2016-01-01

    The role of ultrasound contrast agents (UCA) initially designed for diagnosis has evolved towards a therapeutic use. Ultrasound (US) for triggered drug delivery has many advantages. In particular, it enables a high spatial control of drug release, thus potentially allowing activation of drug delivery only in the targeted region, and not in surrounding healthy tissue. Moreover, UCA imaging can also be used firstly to precisely locate the target region to, and then used to monitor the drug delivery process by tracking the location of release occurrence. All these features make UCA and ultrasound attractive means to mediate drug delivery. The three main potential clinical indications for drug/gene US delivery are (i) the cardiovascular system, (ii) the central nervous system for small molecule delivery, and (iii) tumor therapy using cytotoxic drugs. Although promising results have been achieved in preclinical studies in various animal models, still very few examples of clinical use have been reported. In this chapter will be addressed the aspects pertaining to UCA formulation (chemical composition, mode of preparation, analytical methods…) and the requirement for a potential translation into the clinic following approval by regulatory authorities. PMID:26486339

  18. The delivery of poly(lactic acid)-poly(ethylene glycol) nanoparticles loaded with non-toxic drug to overcome drug resistance for the treatment of neuroblastoma

    NASA Astrophysics Data System (ADS)

    Dhulekar, Jhilmil

    Neuroblastoma is a rare cancer of the sympathetic nervous system. A neuroblastoma tumor develops in the nerve tissue and is diagnosed in infants and children. Approximately 10.2 per million children under the age of 15 are affected in the United States and is slightly more common in boys. Neuroblastoma constitutes 6% of all childhood cancers and has a long-term survival rate of only 15%. There are approximately 700 new cases of neuroblastoma each year in the United States. With such a low rate of survival, the development of more effective treatment methods is necessary. A number of therapies are available for the treatment of these tumors; however, clinicians and their patients face the challenges of systemic side effects and drug resistance of the tumor cells. The application of nanoparticles has the potential to provide a safer and more effective method of delivery drugs to tumors. The advantage of using nanoparticles for drug delivery is the ability to specifically or passively target tumors while reducing the harmful side effects of chemotherapeutics. Drug delivery via nanoparticles can also allow for lower dosage requirements with controlled release of the drugs, which can further reduce systemic toxicity. The aim of this research was to develop a polymeric nanoparticle drug delivery system for the treatment of high-risk neuroblastoma. Nanoparticles composed of a poly(lactic acid)-poly(ethylene glycol) block copolymer were formulated to deliver a non-toxic drug in combination with Temozolomide, a commonly used chemotherapeutic drug for the treatment of neuroblastoma. The non-toxic drug acts as an inhibitor to the DNA-repair protein present in neuroblastoma cells that is responsible for inducing drug resistance in the cells, which would potentially allow for enhanced temozolomide activity. A variety of studies were completed to prove the nanoparticles' low toxicity, loading abilities, and uptake into cells. Additionally, studies were performed to determine the

  19. A Controllable Aptamer-Based Self-Assembled DNA Dendrimer for High Affinity Targeting, Bioimaging and Drug Delivery

    PubMed Central

    Zhang, Huimin; Ma, Yanli; Xie, Yi; An, Yuan; Huang, Yishun; Zhu, Zhi; Yang, Chaoyong James

    2015-01-01

    Targeted drug delivery is important in cancer therapy to decrease the systemic toxicity resulting from nonspecific drug distribution and to enhance drug delivery efficiency. We have developed an aptamer-based DNA dendritic nanostructure as a multifunctional vehicle for targeted cancer cell imaging and drug delivery. The multifunctional DNA dendrimer is constructed from functional Y-shaped building blocks with predesigned base-pairing hybridization including fluorophores, targeting DNA aptamers and intercalated anticancer drugs. With controllable step-by-step self-assembly, the programmable DNA dendrimer has several appealing features, including facile modular design, excellent biostability and biocompatibility, high selectivity, strong binding affinity, good cell internalization efficiency, and high drug loading capacity. Due to the unique structural features of DNA dendrimers, multiple copies of aptamers can be incorporated into each dendrimer, generating a multivalent aptamer-tethered nanostructure with enhanced binding affinity. A model chemotherapeutic anticancer drug, doxorubicin, was delivered via these aptamer-based DNA dendrimers and exerted a potent toxicity for target cancer cells (human T cell acute lymphoblastic leukemia cell line) with low side effects for the non-target cells (human Burkitt’s lymphoma cell line). This controllable aptamer-based DNA dendrimer is a promising candidate for biomedical applications. PMID:25959874

  20. Development and Optimization of a Doxorubicin Loaded Poly Lactic Acid Contrast Agent for Ultrasound Directed Drug Delivery

    PubMed Central

    Eisenbrey, J.R.; Burstein, O. Mualem; Kambhampati, R.; Forsberg, F.; Liu, J-B.; Wheatley, M.A.

    2010-01-01

    An echogenic, intravenous drug delivery platform is proposed in which an encapsulated chemotherapeutic can travel to a desired location and drug delivery can be triggered using external, focused ultrasound at the area of interest. Three methods of loading poly lactic acid (PLA) shelled ultrasound contrast agents (UCA) with doxorubicin are presented. Effects on encapsulation efficiency, in vitro enhancement, stability, particle size, morphology and release during UCA rupture are compared by loading method and drug concentration. An agent containing doxorubicin within the shell was selected as an ideal candidate for future hepatocellular carcinoma studies. The agent achieved a maximal drug load of 6.2 mg Dox/g PLA with an encapsulation efficiency of 20.5%, showed a smooth surface morphology and tight size distribution (poly dispersity index = 0.309) with a peak size of 1865 nm. Acoustically, the agent provided 19 dB of enhancement in vitro at a dosage of 10 µg/ml, with a half life of over 15 mins. In vivo, the agent provided ultrasound enhancement of 13.4 ± 1.6 dB within the ascending aorta of New Zealand rabbits at a dose of 0.15 ml/kg. While the drug-incorporated agent is thought to be well suited for future drug delivery experiments, this study has shown that agent properties can be tailored for specific applications based on choice of drug loading method. PMID:20060024

  1. Nanopharmaceutics: phytochemical-based controlled or sustained drug-delivery systems for cancer treatment.

    PubMed

    Jeetah, Roubeena; Bhaw-Luximon, Archana; Jhurry, Dhanjay

    2014-09-01

    This review is an attempt to assess the different classes of phytochemicals and some of their members which have been encapsulated into nanocarrier systems for their chemotherapeutic or chemopreventive properties. Given the broad spectrum of nanomedicines currently in clinical trial and clinical use from polymer-protein conjugates, through nanocrystals, nanogels, dendrimers to ethosomes, the focus of this review will be on block copolymer nanomicelles, nanoparticles, polymer-drug conjugates, liposomes and solid lipid nanocarriers (SLNs). The twenty phytochemicals investigated for encapsulation and targeted delivery were selected from a variety of classes intended to encompass the largest possible chemical compositions, namely flavonoids, aromatic acids, xanthones, terpenes, quinones, lignans and alkaloids. To the best of our knowledge, reviews on the nanoencapsulation of these phytochemicals and their delivery are not available. In this review, the issues associated with the limited use of each phytochemical in cancer therapy in humans are reviewed and the advantages of entrapment into nanocarriers are assessed in terms of drug loading efficiency, size of nanocarriers, drug release profiles and in vitro and/or in vivo testing specific to cancer research, e.g., cytotoxicity assay, cell inhibition/viability, scavenging of reactive oxygen species and biodistribution studies (elimination half-life and mean residence time). PMID:25992442

  2. Enzyme responsive drug delivery system based on mesoporous silica nanoparticles for tumor therapy in vivo.

    PubMed

    Liu, Yun; Ding, Xingwei; Li, Jinghua; Luo, Zhong; Hu, Yan; Liu, Junjie; Dai, Liangliang; Zhou, Jun; Hou, Changjun; Cai, Kaiyong

    2015-04-10

    To reduce the toxic side effects of traditional chemotherapeutics in vivo, we designed and constructed a biocompatible, matrix metalloproteinases (MMPs) responsive drug delivery system based on mesoporous silica nanoparticles (MSNs). MMPs substrate peptide containing PLGLAR (sensitive to MMPs) was immobilized onto the surfaces of amino-functionalized MSNs via an amidation reaction, serving as MMPs sensitive intermediate linker. Bovine serum albumin was then covalently coupled to linker as end-cap for sealing the mesopores of MSNs. Lactobionic acid was further conjugated to the system as targeting motif. Doxorubicin hydrochloride was used as the model anticancer drug in this study. A series of characterizations revealed that the system was successfully constructed. The peptide-functionalized MSNs system demonstrated relatively high sensitivity to MMPs for triggering drug delivery, which was potentially important for tumor therapy since the tumor's microenvironment overexpressed MMPs in nature. The in vivo experiments proved that the system could efficiently inhibit the tumor growth with minimal side effects. This study provides an approach for the development of the next generation of nanotherapeutics toward efficient cancer treatment. PMID:25789511

  3. Enzyme responsive drug delivery system based on mesoporous silica nanoparticles for tumor therapy in vivo

    NASA Astrophysics Data System (ADS)

    Liu, Yun; Ding, Xingwei; Li, Jinghua; Luo, Zhong; Hu, Yan; Liu, Junjie; Dai, Liangliang; Zhou, Jun; Hou, Changjun; Cai, Kaiyong

    2015-04-01

    To reduce the toxic side effects of traditional chemotherapeutics in vivo, we designed and constructed a biocompatible, matrix metalloproteinases (MMPs) responsive drug delivery system based on mesoporous silica nanoparticles (MSNs). MMPs substrate peptide containing PLGLAR (sensitive to MMPs) was immobilized onto the surfaces of amino-functionalized MSNs via an amidation reaction, serving as MMPs sensitive intermediate linker. Bovine serum albumin was then covalently coupled to linker as end-cap for sealing the mesopores of MSNs. Lactobionic acid was further conjugated to the system as targeting motif. Doxorubicin hydrochloride was used as the model anticancer drug in this study. A series of characterizations revealed that the system was successfully constructed. The peptide-functionalized MSNs system demonstrated relatively high sensitivity to MMPs for triggering drug delivery, which was potentially important for tumor therapy since the tumor’s microenvironment overexpressed MMPs in nature. The in vivo experiments proved that the system could efficiently inhibit the tumor growth with minimal side effects. This study provides an approach for the development of the next generation of nanotherapeutics toward efficient cancer treatment.

  4. Microneedle-based drug delivery systems: Microfabrication, drug delivery, and safety

    PubMed Central

    Donnelly, Ryan F.; Raj Singh, Thakur Raghu; Woolfson, A. David

    2010-01-01

    Many promising therapeutic agents are limited by their inability to reach the systemic circulation, due to the excellent barrier properties of biological membranes, such as the stratum corneum (SC) of the skin or the sclera/cornea of the eye and others. The outermost layer of the skin, the SC, is the principal barrier to topically-applied medications. The intact SC thus provides the main barrier to exogenous substances, including drugs. Only drugs with very specific physicochemical properties (molecular weight < 500 Da, adequate lipophilicity, and low melting point) can be successfully administered transdermally. Transdermal delivery of hydrophilic drugs and macromolecular agents of interest, including peptides, DNA, and small interfering RNA is problematic. Therefore, facilitation of drug penetration through the SC may involve by-pass or reversible disruption of SC molecular architecture. Microneedles (MNs), when used to puncture skin, will by-pass the SC and create transient aqueous transport pathways of micron dimensions and enhance the transdermal permeability. These micropores are orders of magnitude larger than molecular dimensions, and, therefore, should readily permit the transport of hydrophilic macromolecules. Various strategies have been employed by many research groups and pharmaceutical companies worldwide, for the fabrication of MNs. This review details various types of MNs, fabrication methods and, importantly, investigations of clinical safety of MN. PMID:20297904

  5. Coacervate delivery systems for proteins and small molecule drugs

    PubMed Central

    Johnson, Noah R; Wang, Yadong

    2015-01-01

    Coacervates represent an exciting new class of drug delivery vehicles, developed in the past decade as carriers of small molecule drugs and proteins. This review summarizes several well-described coacervate systems, including Elastin-like peptides for delivery of anti-cancer therapeutics,Heparin-based coacervates with synthetic polycations for controlled growth factor delivery,Carboxymethyl chitosan aggregates for oral drug delivery,Mussel adhesive protein and hyaluronic acid coacervates. Coacervates present advantages in their simple assembly and easy incorporation into tissue engineering scaffolds or as adjuncts to cell therapies. They are also amenable to functionalization such as for targeting or for enhancing the bioactivity of their cargo. These new drug carriers are anticipated to have broad applications and noteworthy impact in the near future. PMID:25138695

  6. Carbon nanotubes for delivery of small molecule drugs.

    PubMed

    Wong, Bin Sheng; Yoong, Sia Lee; Jagusiak, Anna; Panczyk, Tomasz; Ho, Han Kiat; Ang, Wee Han; Pastorin, Giorgia

    2013-12-01

    In the realm of drug delivery, carbon nanotubes (CNTs) have gained tremendous attention as promising nanocarriers, owing to their distinct characteristics, such as high surface area, enhanced cellular uptake and the possibility to be easily conjugated with many therapeutics, including both small molecules and biologics, displaying superior efficacy, enhanced specificity and diminished side effects. While most CNT-based drug delivery system (DDS) had been engineered to combat cancers, there are also emerging reports that employ CNTs as either the main carrier or adjunct material for the delivery of various non-anticancer drugs. In this review, the delivery of small molecule drugs is expounded, with special attention paid to the current progress of in vitro and in vivo research involving CNT-based DDSs, before finally concluding with some consideration on inevitable complications that hamper successful disease intervention with CNTs. PMID:23954402

  7. A smart pill for drug delivery with sensing capabilities.

    PubMed

    Goffredo, R; Accoto, D; Santonico, M; Pennazza, G; Guglielmelli, E

    2015-08-01

    In this paper a novel system for local drug delivery is described. The actuation principle of the micropump used for drug delivery relies on the electrolysis of a water-based solution, which is separated from a drug reservoir by an elastic membrane. The electrolytically produced gases pressurize the electrolytic solution reservoir, causing the deflection of the elastic membrane. Such deflection, in turn, forces the drug out of its reservoir through a nozzle. The proposed system is integrated in a swallowable capsule, equipped with an impedance sensor useful to acquire information on the physiological conditions of the tissue. Such information can be used to control pump activation. PMID:26736521

  8. Micelles and Nanoparticles for Ultrasonic Drug and Gene Delivery

    PubMed Central

    Husseini, Ghaleb A.; Pitt, William G.

    2008-01-01

    Drug delivery research employing micelles and nanoparticles has expanded in recent years. Of particular interest is the use of these nanovehicles that deliver high concentrations of cytotoxic drugs to diseased tissues selectively, thus reducing the agent’s side effects on the rest of the body. Ultrasound, traditionally used in diagnostic medicine, is finding a place in drug delivery in connection with these nanoparticles. In addition to their non-invasive nature and the fact that they can be focused on targeted tissues, acoustic waves have been credited with releasing pharmacological agents from nanocarriers, as well as rendering cell membranes more permeable. In this article, we summarize new technologies that combine the use of nanoparticles with acoustic power both in drug and gene delivery. Ultrasonic drug delivery from micelles usually employs polyether block copolymers, and has been found effective in vivo for treating tumors. Ultrasound releases drug from micelles, most probably via shear stress and shock waves from collapse of cavitation bubbles. Liquid emulsions and solid nanoparticles are used with ultrasound to deliver genes in vitro and in vivo. The small packaging allows nanoparticles to extravasate into tumor tissues. Ultrasonic drug and gene delivery from nano-carriers has tremendous potential because of the wide variety of drugs and genes that could be delivered to targeted tissues by fairly non-invasive means. PMID:18486269

  9. Albumin-based nanocomposite spheres for advanced drug delivery systems.

    PubMed

    Misak, Heath E; Asmatulu, Ramazan; Gopu, Janani S; Man, Ka-Poh; Zacharias, Nora M; Wooley, Paul H; Yang, Shang-You

    2014-01-01

    A novel drug delivery system incorporating human serum albumin, poly(lactic-co-glycolic acid, magnetite nanoparticles, and therapeutic agent(s) was developed for potential application in the treatment of diseases such as rheumatoid arthritis and skin cancer. An oil-in-oil emulsion/solvent evaporation (O/OSE) method was modified to produce a drug delivery system with a diameter of 0.5–2 μm. The diameter was mainly controlled by adjusting the viscosity of albumin in the discontinuous phase of the O/OSE method. The drug-release study showed that the release of drug and albumin was mostly dependent on the albumin content of the drug delivery system, which is very similar to the drug occlusion-mesopore model. Cytotoxicity tests indicated that increasing the albumin content in the drug delivery system increased cell viability, possibly due to the improved biocompatibility of the system. Overall, these studies show that the proposed system could be a viable option as a drug delivery system in the treatment of many illnesses, such as rheumatoid arthritis, and skin and breast cancers. PMID:24106002

  10. Nanoparticle hardness controls the internalization pathway for drug delivery

    NASA Astrophysics Data System (ADS)

    Li, Ye; Zhang, Xianren; Cao, Dapeng

    2015-01-01

    Nanoparticle (NP)-based drug delivery systems offer fundamental advantages over current therapeutic agents that commonly display a longer circulation time, lower toxicity, specific targeted release, and greater bioavailability. For successful NP-based drug delivery it is essential that the drug-carrying nanocarriers can be internalized by the target cells and transported to specific sites, and the inefficient internalization of nanocarriers is often one of the major sources for drug resistance. In this work, we use the dissipative particle dynamics simulation to investigate the effect of NP hardness on their internalization efficiency. Three simplified models of NP platforms for drug delivery, including polymeric NP, liposome and solid NP, are designed here to represent increasing nanocarrier hardness. Simulation results indicate that NP hardness controls the internalization pathway for drug delivery. Rigid NPs can enter the cell by a pathway of endocytosis, whereas for soft NPs the endocytosis process can be inhibited or frustrated due to wrapping-induced shape deformation and non-uniform ligand distribution. Instead, soft NPs tend to find one of three penetration pathways to enter the cell membrane via rearranging their hydrophobic and hydrophilic segments. Finally, we show that the interaction between nanocarriers and drug molecules is also essential for effective drug delivery.

  11. Gastroretentive drug delivery systems for the treatment of Helicobacter pylori

    PubMed Central

    Zhao, Shan; Lv, Yan; Zhang, Jian-Bin; Wang, Bing; Lv, Guo-Jun; Ma, Xiao-Jun

    2014-01-01

    Helicobacter pylori (H. pylori) is one of the most common pathogenic bacterial infections and is found in the stomachs of approximately half of the world’s population. It is the primary known cause of gastritis, gastroduodenal ulcer disease and gastric cancer. However, combined drug therapy as the general treatment in the clinic, the rise of antibiotic-resistant bacteria, adverse reactions and poor patient compliance are major obstacles to the eradication of H. pylori. Oral site-specific drug delivery systems that could increase the longevity of the treatment agent at the target site might improve the therapeutic effect and avoid side effects. Gastroretentive drug delivery systems potentially prolong the gastric retention time and controlled/sustained release of a drug, thereby increasing the concentration of the drug at the application site, potentially improving its bioavailability and reducing the necessary dosage. Recommended gastroretentive drug delivery systems for enhancing local drug delivery include floating systems, bioadhesive systems and expandable systems. In this review, we summarize the important physiological parameters of the gastrointestinal tract that affect the gastric residence time. We then focus on various aspects useful in the development of gastroretentive drug delivery systems, including current trends and the progress of novel forms, especially with respect to their application for the treatment of H. pylori infections. PMID:25071326

  12. A smart multifunctional drug delivery nanoplatform for targeting cancer cells.

    PubMed

    Hoop, M; Mushtaq, F; Hurter, C; Chen, X-Z; Nelson, B J; Pané, S

    2016-07-01

    Wirelessly guided magnetic nanomachines are promising vectors for targeted drug delivery, which have the potential to minimize the interaction between anticancer agents and healthy tissues. In this work, we propose a smart multifunctional drug delivery nanomachine for targeted drug delivery that incorporates a stimuli-responsive building block. The nanomachine consists of a magnetic nickel (Ni) nanotube that contains a pH-responsive chitosan hydrogel in its inner cavity. The chitosan inside the nanotube serves as a matrix that can selectively release drugs in acidic environments, such as the extracellular space of most tumors. Approximately a 2.5 times higher drug release from Ni nanotubes at pH = 6 is achieved compared to that at pH = 7.4. The outside of the Ni tube is coated with gold. A fluorescein isothiocyanate (FITC) labeled thiol-ssDNA, a biological marker, was conjugated on its surface by thiol-gold click chemistry, which enables traceability. The Ni nanotube allows the propulsion of the device by means of external magnetic fields. As the proposed nanoarchitecture integrates different functional building blocks, our drug delivery nanoplatform can be employed for carrying molecular drug conjugates and for performing targeted combinatorial therapies, which can provide an alternative and supplementary solution to current drug delivery technologies. PMID:27297037

  13. Transferosomes - A vesicular transdermal delivery system for enhanced drug permeation

    PubMed Central

    Rajan, Reshmy; Jose, Shoma; Mukund, V. P. Biju; Vasudevan, Deepa T.

    2011-01-01

    Transdermal administration of drugs is generally limited by the barrier function of the skin. Vesicular systems are one of the most controversial methods for transdermal delivery of active substances. The interest in designing transdermal delivery systems was relaunched after the discovery of elastic vesicles like transferosomes, ethosomes, cubosomes, phytosomes, etc. This paper presents the composition, mechanisms of penetration, manufacturing and characterization methods of transferosomes as transdermal delivery systems of active substances. For a drug to be absorbed and distributed into organs and tissues and eliminated from the body, it must pass through one or more biological membranes/barriers at various locations. Such a movement of drug across the membrane is called as drug transport. For the drugs to be delivered to the body, they should cross the membranous barrier. The concept of these delivery systems was designed in an attempt to concentrate the drug in the tissues of interest, while reducing the amount of drug in the remaining tissues. Hence, surrounding tissues are not affected by the drug. In addition, loss of drug does not happen due to localization of drug, leading to get maximum efficacy of the medication. Therefore, the phospholipid based carrier systems are of considerable interest in this era. PMID:22171309

  14. Transferosomes - A vesicular transdermal delivery system for enhanced drug permeation.

    PubMed

    Rajan, Reshmy; Jose, Shoma; Mukund, V P Biju; Vasudevan, Deepa T

    2011-07-01

    Transdermal administration of drugs is generally limited by the barrier function of the skin. Vesicular systems are one of the most controversial methods for transdermal delivery of active substances. The interest in designing transdermal delivery systems was relaunched after the discovery of elastic vesicles like transferosomes, ethosomes, cubosomes, phytosomes, etc. This paper presents the composition, mechanisms of penetration, manufacturing and characterization methods of transferosomes as transdermal delivery systems of active substances. For a drug to be absorbed and distributed into organs and tissues and eliminated from the body, it must pass through one or more biological membranes/barriers at various locations. Such a movement of drug across the membrane is called as drug transport. For the drugs to be delivered to the body, they should cross the membranous barrier. The concept of these delivery systems was designed in an attempt to concentrate the drug in the tissues of interest, while reducing the amount of drug in the remaining tissues. Hence, surrounding tissues are not affected by the drug. In addition, loss of drug does not happen due to localization of drug, leading to get maximum efficacy of the medication. Therefore, the phospholipid based carrier systems are of considerable interest in this era. PMID:22171309

  15. Mucus-penetrating nanoparticles for vaginal and gastrointestinal drug delivery

    NASA Astrophysics Data System (ADS)

    Ensign-Hodges, Laura

    A method that could provide more uniform and longer-lasting drug delivery to mucosal surfaces holds the potential to greatly improve the effectiveness of prophylactic and therapeutic approaches for numerous diseases and conditions, including sexually transmitted infections and inflammatory bowel disease. However, the body's natural defenses, including adhesive, rapidly cleared mucus linings coating nearly all entry points to the body not covered by skin, has limited the effectiveness of drug and gene delivery by nanoscale delivery systems. Here, we investigate the use of muco-inert mucus-penetrating nanoparticles (MPP) for improving vaginal and gastrointestinal drug delivery. Conventional hydrophobic nanoparticles strongly adhere to mucus, facilitating rapid clearance from the body. Here, we demonstrate that mucoadhesive polystyrene nanoparticles (conventional nanoparticles, CP) become mucus-penetrating in human cervicovaginal mucus (CVM) after pretreatment with sufficient concentrations of Pluronic F127. Importantly, the diffusion rate of large MPP did not change in F127 pretreated CVM, implying there is no affect on the native pore structure of CVM. Additionally, there was no increase in inflammatory cytokine release in the vaginal tract of mice after daily application of 1% F127 for one week. Importantly, HSV virus remains adherent in F127-pretreated CVM. Mucosal epithelia use osmotic gradients for fluid absorption and secretion. We hypothesized that hypotonically-induced fluid uptake could be advantageous for rapidly delivering drugs through mucus to the vaginal epithelium. We evaluated hypotonic formulations for delivering water-soluble drugs and for drug delivery with MPP. Hypotonic formulations markedly increased the rate at which drugs and MPP reached the epithelial surface. Additionally, hypotonic formulations greatly enhanced drug and MPP delivery to the entire epithelial surface, including deep into the vaginal folds (rugae) that isotonic formulations

  16. Review on triggered liposomal drug delivery with a focus on ultrasound.

    PubMed

    Moussa, Hesham G; Martins, Ana M; Husseini, Ghaleb A

    2015-01-01

    Chemotherapy is widely used for cancer treatment; however, it causes unwanted side effects in patients. To avoid these adverse effects, nanocarriers have been developed, which can be loaded with the chemotherapeutic agents, directed to the cancer site and, once there, are exposed to stimuli that will trigger the drug release. Liposomes can be chemically modified to increase their circulation time, their stability, and their sensitivity to specific stimulus. Additionally, ligands can be conjugated to their surface, allowing for their specific binding to receptors overexpressed on the surface of cancer cells and the subsequent internalization via endocytosis. Using a triggering mechanism, including temperature, ultrasound, enzymes or a change in pH, the release of the drug is controlled and induced inside the cells, hence avoiding drug release in systemic circulation, which in turn reduces the undesired side effects of conventional chemotherapy. Ultrasound has been widely studied as a drug release trigger from liposomes, due to its well-known physics and previous uses in medicine. This review focuses on liposome-based drug delivery systems, using different trigger mechanisms, with a focus on ultrasound. The physical mechanisms of ultrasound release are also investigated and the results of in vitro and in vivo studies are summarized. PMID:25760762

  17. Critical Assessment of Implantable Drug Delivery Devices in Glaucoma Management

    PubMed Central

    Manickavasagam, Dharani; Oyewumi, Moses O.

    2013-01-01

    Glaucoma is a group of heterogeneous disorders involving progressive optic neuropathy that can culminate into visual impairment and irreversible blindness. Effective therapeutic interventions must address underlying vulnerability of retinal ganglion cells (RGCs) to degeneration in conjunction with correcting other associated risk factors (such as elevated intraocular pressure). However, realization of therapeutic outcomes is heavily dependent on suitable delivery system that can overcome myriads of anatomical and physiological barriers to intraocular drug delivery. Development of clinically viable sustained release systems in glaucoma is a widely recognized unmet need. In this regard, implantable delivery systems may relieve the burden of chronic drug administration while potentially ensuring high intraocular drug bioavailability. Presently there are no FDA-approved implantable drug delivery devices for glaucoma even though there are several ongoing clinical studies. The paper critically assessed the prospects of polymeric implantable delivery systems in glaucoma while identifying factors that can dictate (a) patient tolerability and acceptance, (b) drug stability and drug release profiles, (c) therapeutic efficacy, and (d) toxicity and biocompatibility. The information gathered could be useful in future research and development efforts on implantable delivery systems in glaucoma. PMID:24066234

  18. Iontophoresis: A Potential Emergence of a Transdermal Drug Delivery System

    PubMed Central

    Dhote, Vinod; Bhatnagar, Punit; Mishra, Pradyumna K.; Mahajan, Suresh C.; Mishra, Dinesh K.

    2012-01-01

    The delivery of drugs into systemic circulation via skin has generated much attention during the last decade. Transdermal therapeutic systems propound controlled release of active ingredients through the skin and into the systemic circulation in a predictive manner. Drugs administered through these systems escape first-pass metabolism and maintain a steady state scenario similar to a continuous intravenous infusion for up to several days. However, the excellent impervious nature of the skin offers the greatest challenge for successful delivery of drug molecules by utilizing the concepts of iontophoresis. The present review deals with the principles and the recent innovations in the field of iontophoretic drug delivery system together with factors affecting the system. This delivery system utilizes electric current as a driving force for permeation of ionic and non-ionic medications. The rationale behind using this technique is to reversibly alter the barrier properties of skin, which could possibly improve the penetration of drugs such as proteins, peptides and other macromolecules to increase the systemic delivery of high molecular weight compounds with controlled input kinetics and minimum inter-subject variability. Although iontophoresis seems to be an ideal candidate to overcome the limitations associated with the delivery of ionic drugs, further extrapolation of this technique is imperative for translational utility and mass human application. PMID:22396901

  19. Planar bioadhesive microdevices: a new technology for oral drug delivery

    PubMed Central

    Fox, Cade B.; Chirra, Hariharasudhan D.; Desai, Tejal A.

    2014-01-01

    The oral route is the most convenient and least expensive route of drug administration. Yet, it is accompanied by many physiological barriers to drug uptake including low stomach pH, intestinal enzymes and transporters, mucosal barriers, and high intestinal fluid shear. While many drug delivery systems have been developed for oral drug administration, the physiological components of the gastro intestinal tract remain formidable barriers to drug uptake. Recently, microfabrication techniques have been applied to create micron-scale devices for oral drug delivery with a high degree of control over microdevice size, shape, chemical composition, drug release profile, and targeting ability. With precise control over device properties, microdevices can be fabricated with characteristics that provide increased adhesion for prolonged drug exposure, unidirectional release which serves to avoid luminal drug loss and enhance drug permeation, and protection of a drug payload from the harsh environment of the intestinal tract. Here we review the recent developments in microdevice technology and discuss the potential of these devices to overcome unsolved challenges in oral drug delivery. PMID:25219863

  20. Drug delivery systems for ovarian cancer treatment: a systematic review and meta-analysis of animal studies

    PubMed Central

    Raavé, René; de Vries, Rob B.M.; Massuger, Leon F.; van Kuppevelt, Toin H.

    2015-01-01

    Current ovarian cancer treatment involves chemotherapy that has serious limitations, such as rapid clearance, unfavorable biodistribution and severe side effects. To overcome these limitations, drug delivery systems (DDS) have been developed to encapsulate chemotherapeutics for delivery to tumor cells. However, no systematic assessment of the efficacy of chemotherapy by DDS compared to free chemotherapy (not in a DDS) has been performed for animal studies. Here, we assess the efficacy of chemotherapy in DDS on survival and tumor growth inhibition in animal studies. We searched PubMed and EMBASE (via OvidSP) to systematically identify studies evaluating chemotherapeutics encapsulated in DDS for ovarian cancer treatment in animal studies. Studies were assessed for quality and risk of bias. Study characteristics were collected and outcome data (survival/hazard ratio or tumor growth inhibition) were extracted and used for meta-analyses. Meta-analysis was performed to identify and explore which characteristics of DDS influenced treatment efficacy. A total of 44 studies were included after thorough literature screening (2,735 studies found after initial search). The risk of bias was difficult to assess, mainly because of incomplete reporting. A total of 17 studies (377 animals) and 16 studies (259 animals) could be included in the meta-analysis for survival and tumor growth inhibition, respectively. In the majority of the included studies chemotherapeutics entrapped in a DDS significantly improved efficacy over free chemotherapeutics regarding both survival and tumor growth inhibition. Subgroup analyses, however, revealed that cisplatin entrapped in a DDS did not result in additional tumor growth inhibition compared to free cisplatin, although it did result in improved survival. Micelles did not show a significant tumor growth inhibition compared to free chemotherapeutics, which indicates that micelles may not be a suitable DDS for ovarian cancer treatment. Other

  1. A Review on Composite Liposomal Technologies for Specialized Drug Delivery

    PubMed Central

    Mufamadi, Maluta S.; Pillay, Viness; Choonara, Yahya E.; Du Toit, Lisa C.; Modi, Girish; Naidoo, Dinesh; Ndesendo, Valence M. K.

    2011-01-01

    The combination of liposomes with polymeric scaffolds could revolutionize the current state of drug delivery technology. Although liposomes have been extensively studied as a promising drug delivery model for bioactive compounds, there still remain major drawbacks for widespread pharmaceutical application. Two approaches for overcoming the factors related to the suboptimal efficacy of liposomes in drug delivery have been suggested. The first entails modifying the liposome surface with functional moieties, while the second involves integration of pre-encapsulated drug-loaded liposomes within depot polymeric scaffolds. This attempts to provide ingenious solutions to the limitations of conventional liposomes such as short plasma half-lives, toxicity, stability, and poor control of drug release over prolonged periods. This review delineates the key advances in composite technologies that merge the concepts of depot polymeric scaffolds with liposome technology to overcome the limitations of conventional liposomes for pharmaceutical applications. PMID:21490759

  2. Assessment of liposome disruption to quantify drug delivery in vitro.

    PubMed

    Nogueira, Eugénia; Cruz, Célia F; Loureiro, Ana; Nogueira, Patrícia; Freitas, Jaime; Moreira, Alexandra; Carmo, Alexandre M; Gomes, Andreia C; Preto, Ana; Cavaco-Paulo, Artur

    2016-02-01

    Efficient liposome disruption inside the cells is a key for success with any type of drug delivery system. The efficacy of drug delivery is currently evaluated by direct visualization of labeled liposomes internalized by cells, not addressing objectively the release and distribution of the drug. Here, we propose a novel method to easily assess liposome disruption and drug release into the cytoplasm. We propose the encapsulation of the cationic dye Hoechst 34580 to detect an increase in blue fluorescence due to its specific binding to negatively charged DNA. For that, the dye needs to be released inside the cell and translocated to the nucleus. The present approach correlates the intensity of detected fluorescent dye with liposome disruption and consequently assesses drug delivery within the cells. PMID:26589183

  3. Oral Dispersible System: A New Approach in Drug Delivery System

    PubMed Central

    Hannan, P. A.; Khan, J. A.; Khan, A.; Safiullah, S.

    2016-01-01

    Dosage form is a mean used for the delivery of drug to a living body. In order to get the desired effect the drug should be delivered to its site of action at such rate and concentration to achieve the maximum therapeutic effect and minimum adverse effect. Since oral route is still widely accepted route but having a common drawback of difficulty in swallowing of tablets and capsules. Therefore a lot of research has been done on novel drug delivery systems. This review is about oral dispersible tablets a novel approach in drug delivery systems that are now a day's more focused in formulation world, and laid a new path that, helped the patients to build their compliance level with the therapy, also reduced the cost and ease the administration especially in case of pediatrics and geriatrics. Quick absorption, rapid onset of action and reduction in drug loss properties are the basic advantages of this dosage form. PMID:27168675

  4. Nerve guidance channels as drug delivery vehicles.

    PubMed

    Piotrowicz, Alexandra; Shoichet, Molly S

    2006-03-01

    Nerve guidance channels (NGCs) have been shown to facilitate regeneration after transection injury to the peripheral nerve or spinal cord. Various therapeutic molecules, including neurotrophic factors, have improved regeneration and functional recovery after injury when combined with NGCs; however, their impact has not been maximized partly due to the lack of an appropriate drug delivery system. To address this limitation, nerve growth factor (NGF) was incorporated into NGCs of poly(2-hydroxyethyl methacrylate-co-methyl methacrylate), P(HEMA-co-MMA). The NGCs were synthesized by a liquid-liquid centrifugal casting process and three different methods of protein incorporation were compared in terms of protein distribution and NGF release profile: (1) NGF was encapsulated (with BSA) in biodegradable poly(d,l-lactide-co-glycolide) 85/15 microspheres, which were combined with a PHEMA polymerization formulation and coated on the inside of pre-formed NGCs by a second liquid-liquid centrifugal casting technique; (2) pre-formed NGCs were imbibed with a solution of NGF/BSA and (3) NGF/BSA alone was combined with a PHEMA formulation and coated on the inside of pre-formed NGCs by a second liquid-liquid centrifugal casting technique. Using a fluorescently labelled model protein, the distribution of proteins in NGCs prepared with a coating of either protein-loaded microspheres or protein alone was found to be confined to the inner PHEMA layer. Sustained release of NGF was achieved from NGCs with either NGF-loaded microspheres or NGF alone incorporated into the inner layer, but not from channels imbibed with NGF. By day 28, NGCs with microspheres released a total of 220 pg NGF/cm of channel whereas those NGCs imbibed with NGF released 1040 pg/cm and those NGCs with NGF incorporated directly in a PHEMA layer released 8624 pg/cm. The release of NGF from NGCs with microspheres was limited by a slow-degrading microsphere formulation and by the maximum amount of microspheres that

  5. Targeted electrohydrodynamic printing for micro-reservoir drug delivery systems

    NASA Astrophysics Data System (ADS)

    Hwang, Tae Heon; Kim, Jin Bum; Som Yang, Da; Park, Yong-il; Ryu, WonHyoung

    2013-03-01

    Microfluidic drug delivery systems consisting of a drug reservoir and microfluidic channels have shown the possibility of simple and robust modulation of drug release rate. However, the difficulty of loading a small quantity of drug into drug reservoirs at a micro-scale limited further development of such systems. Electrohydrodynamic (EHD) printing was employed to fill micro-reservoirs with controlled amount of drugs in the range of a few hundreds of picograms to tens of micrograms with spatial resolution of as small as 20 µm. Unlike most EHD systems, this system was configured in combination with an inverted microscope that allows in situ targeting of drug loading at micrometer scale accuracy. Methylene blue and rhodamine B were used as model drugs in distilled water, isopropanol and a polymer solution of a biodegradable polymer and dimethyl sulfoxide (DMSO). Also tetracycline-HCl/DI water was used as actual drug ink. The optimal parameters of EHD printing to load an extremely small quantity of drug into microscale drug reservoirs were investigated by changing pumping rates, the strength of an electric field and drug concentration. This targeted EHD technique was used to load drugs into the microreservoirs of PDMS microfluidic drug delivery devices and their drug release performance was demonstrated in vitro.

  6. Nanostructured materials for applications in drug delivery and tissue engineering*

    PubMed Central

    GOLDBERG, MICHAEL; LANGER, ROBERT; JIA, XINQIAO

    2010-01-01

    Research in the areas of drug delivery and tissue engineering has witnessed tremendous progress in recent years due to their unlimited potential to improve human health. Meanwhile, the development of nanotechnology provides opportunities to characterize, manipulate and organize matter systematically at the nanometer scale. Biomaterials with nano-scale organizations have been used as controlled release reservoirs for drug delivery and artificial matrices for tissue engineering. Drug-delivery systems can be synthesized with controlled composition, shape, size and morphology. Their surface properties can be manipulated to increase solubility, immunocompatibility and cellular uptake. The limitations of current drug delivery systems include suboptimal bioavailability, limited effective targeting and potential cytotoxicity. Promising and versatile nano-scale drug-delivery systems include nanoparticles, nanocapsules, nanotubes, nanogels and dendrimers. They can be used to deliver both small-molecule drugs and various classes of biomacromolecules, such as peptides, proteins, plasmid DNA and synthetic oligodeoxynucleotides. Whereas traditional tissue-engineering scaffolds were based on hydrolytically degradable macroporous materials, current approaches emphasize the control over cell behaviors and tissue formation by nano-scale topography that closely mimics the natural extracellular matrix (ECM). The understanding that the natural ECM is a multifunctional nanocomposite motivated researchers to develop nanofibrous scaffolds through electrospinning or self-assembly. Nanocomposites containing nanocrystals have been shown to elicit active bone growth. Drug delivery and tissue engineering are closely related fields. In fact, tissue engineering can be viewed as a special case of drug delivery where the goal is to accomplish controlled delivery of mammalian cells. Controlled release of therapeutic factors in turn will enhance the efficacy of tissue engineering. From a materials

  7. Intracellular Delivery System for Antibody–Peptide Drug Conjugates

    PubMed Central

    Berguig, Geoffrey Y; Convertine, Anthony J; Frayo, Shani; Kern, Hanna B; Procko, Erik; Roy, Debashish; Srinivasan, Selvi; Margineantu, Daciana H; Booth, Garrett; Palanca-Wessels, Maria Corinna; Baker, David; Hockenbery, David; Press, Oliver W; Stayton, Patrick S

    2015-01-01

    Antibodies armed with biologic drugs could greatly expand the therapeutic potential of antibody–drug conjugates for cancer therapy, broadening their application to disease targets currently limited by intracellular delivery barriers. Additional selectivity and new therapeutic approaches could be realized with intracellular protein drugs that more specifically target dysregulated pathways in hematologic cancers and other malignancies. A multifunctional polymeric delivery system for enhanced cytosolic delivery of protein drugs has been developed that incorporates endosomal-releasing activity, antibody targeting, and a biocompatible long-chain ethylene glycol component for optimized safety, pharmacokinetics, and tumor biodistribution. The pH-responsive polymeric micelle carrier, with an internalizing anti-CD22 monoclonal targeting antibody, effectively delivered a proapoptotic Bcl-2 interacting mediator (BIM) peptide drug that suppressed tumor growth for the duration of treatment and prolonged survival in a xenograft mouse model of human B-cell lymphoma. Antitumor drug activity was correlated with a mechanistic induction of the Bcl-2 pathway biomarker cleaved caspase-3 and a marked decrease in the Ki-67 proliferation biomarker. Broadening the intracellular target space by more effective delivery of protein/peptide drugs could expand the repertoire of antibody–drug conjugates to currently undruggable disease-specific targets and permit tailored drug strategies to stratified subpopulations and personalized medicines. PMID:25669432

  8. New Insights into the Mechanism Underlying the Synergistic Action of Ionizing Radiation With Platinum Chemotherapeutic Drugs: The Role of Low-Energy Electrons

    SciTech Connect

    Rezaee, Mohammad Hunting, Darel John; Sanche, Léon

    2013-11-15

    Purpose: To investigate the efficiencies of platinum chemotherapeutic drugs (Pt-drugs) in the sensitization of DNA to the direct effects of ionizing radiation and to determine the role of low-energy electrons (LEEs) in this process. Methods and Materials: Complexes of supercoiled plasmid DNA covalently bound to either cisplatin, carboplatin, or oxaliplatin were prepared in different molar ratios. Solid films of DNA and DNA modified by Pt-drugs were irradiated with either 10-KeV or 10-eV electrons. Damages to DNA were quantified by gel electrophoresis, and the yields for damage formation were obtained from exposure–response curves. Results: The presence of an average of 2 Pt-drug–DNA adducts (Pt-adducts) in 3199-bp plasmid DNA increases the probability of a double-strand break by factors of 3.1, 2.5, and 2.4 for carboplatin, cisplatin, and oxaliplatin, respectively. Electrons with energies of 10 eV and 10 KeV interact with Pt-adducts to preferentially enhance the formation of cluster lesions. The maximum increase in radiosensitivity per Pt-adduct is found at ratios up to 3.1 × 10{sup −4} Pt-adducts per nucleotide, which is equivalent to an average of 2 adducts per plasmid. Carboplatin and oxaliplatin show higher efficiencies than cisplatin in the radiosensitization of DNA. Because carboplatin and cisplatin give rise to identical reactive species that attach to DNA, carboplatin must be considered as a better radiosensitizer for equal numbers of Pt-adducts. Conclusion: Platinum chemotherapeutic drugs preferentially enhance the formation of cluster damage to DNA induced by the direct effect of ionizing radiation, and LEEs are the main species responsible for such an enhancement via the formation of electron resonances.

  9. Design of an implantable device for ocular drug delivery.

    PubMed

    Lee, Jae-Hwan; Pidaparti, Ramana M; Atkinson, Gary M; Moorthy, Ramana S

    2012-01-01

    Ocular diseases, such as, glaucoma, age-related macular degeneration (AMD), diabetic retinopathy, and retinitis pigmentosa require drug management in order to prevent blindness and affecting million of adults in USA and worldwide. There is an increasing need to develop devices for drug delivery to address ocular diseases. This study focuses on the design, simulation, and development of an implantable ocular drug delivery device consisting of micro-/nanochannels embedded between top and bottom covers with a drug reservoir made from polydimethylsiloxane (PDMS) which is silicon-based organic and biodegradable polymer. Several simulations were carried out with six different micro-channel configurations in order to see the feasibility for ocular drug delivery applications. Based on the results obtained, channel design of osmotic I and osmotic II satisfied the diffusion rates required for ocular drug delivery. Finally, a prototype illustrating the three components of the drug delivery design is presented. In the future, the device will be tested for its functionality and diffusion characteristics. PMID:22919500

  10. Drug Delivery Systems, CNS Protection, and the Blood Brain Barrier

    PubMed Central

    Upadhyay, Ravi Kant

    2014-01-01

    Present review highlights various drug delivery systems used for delivery of pharmaceutical agents mainly antibiotics, antineoplastic agents, neuropeptides, and other therapeutic substances through the endothelial capillaries (BBB) for CNS therapeutics. In addition, the use of ultrasound in delivery of therapeutic agents/biomolecules such as proline rich peptides, prodrugs, radiopharmaceuticals, proteins, immunoglobulins, and chimeric peptides to the target sites in deep tissue locations inside tumor sites of brain has been explained. In addition, therapeutic applications of various types of nanoparticles such as chitosan based nanomers, dendrimers, carbon nanotubes, niosomes, beta cyclodextrin carriers, cholesterol mediated cationic solid lipid nanoparticles, colloidal drug carriers, liposomes, and micelles have been discussed with their recent advancements. Emphasis has been given on the need of physiological and therapeutic optimization of existing drug delivery methods and their carriers to deliver therapeutic amount of drug into the brain for treatment of various neurological diseases and disorders. Further, strong recommendations are being made to develop nanosized drug carriers/vehicles and noninvasive therapeutic alternatives of conventional methods for better therapeutics of CNS related diseases. Hence, there is an urgent need to design nontoxic biocompatible drugs and develop noninvasive delivery methods to check posttreatment clinical fatalities in neuropatients which occur due to existing highly toxic invasive drugs and treatment methods. PMID:25136634

  11. NMR techniques in drug delivery: application to zein protein complexes.

    PubMed

    Sousa, F F O; Luzardo-Álvarez, Asteria; Blanco-Méndez, José; Martín-Pastor, Manuel

    2012-12-15

    Zein is a protein containing a large amount of nonpolar amino acids, which has shown the ability to form aggregates and entrap solutes, such as drugs and amino acids. NMR techniques were used to detect binding interactions and measure affinity between zein and three different drugs: tetracycline, amoxicillin and indomethacin. The release study of zein microparticle formulations containing any of these drugs was confronted with the affinity results, showing a remarkable correlation. The feasible methodology employed, focused in the functionality of the protein-drug interaction, can be very promising for the rational design of appropriate drug vehicles for drug delivery. PMID:23041651

  12. Dual-drug delivery by porous silicon nanoparticles for improved cellular uptake, sustained release, and combination therapy.

    PubMed

    Wang, Chang-Fang; Mäkilä, Ermei M; Kaasalainen, Martti H; Hagström, Marja V; Salonen, Jarno J; Hirvonen, Jouni T; Santos, Hélder A

    2015-04-01

    Dual-drug delivery of antiangiogenic and chemotherapeutic drugs can enhance the therapeutic effect for cancer therapy. Conjugation of methotrexate (MTX) to porous silicon (PSi) nanoparticles (MTX-PSi) with positively charged surface can improve the cellular uptake of MTX and inhibit the proliferation of cancer cells. Herein, MTX-PSi conjugates sustained the release of MTX up to 96 h, and the released fragments including MTX were confirmed by mass spectrometry. The intracellular distribution of the MTX-PSi nanoparticles was confirmed by transmission electron microscopy. Compared to pure MTX, the MTX-PSi achieved similar inhibition of cell proliferation in folate receptor (FR) over-expressing U87 MG cancer cells, and a higher effect in low FR-expressing EA.hy926 cells. Nuclear fragmentation analysis demonstrated programmed cell apoptosis of MTX-PSi in the high/low FR-expressing cancer cells, whereas PSi alone at the same dose had a minor effect on cell apoptosis. Finally, the porous structure of MTX-PSi enabled a successful concomitant loading of another anti-angiogenic hydrophobic drug, sorafenib, and considerably enhanced the dissolution rate of sorafenib. Overall, the MTX-PSi nanoparticles can be used as a platform for combination chemotherapy by simultaneously enhancing the dissolution rate of a hydrophobic drug and sustaining the release of a conjugated chemotherapeutic drug. PMID:25637067

  13. Mucus-penetrating nanoparticles for vaginal and gastrointestinal drug delivery

    NASA Astrophysics Data System (ADS)

    Ensign-Hodges, Laura

    A method that could provide more uniform and longer-lasting drug delivery to mucosal surfaces holds the potential to greatly improve the effectiveness of prophylactic and therapeutic approaches for numerous diseases and conditions, including sexually transmitted infections and inflammatory bowel disease. However, the body's natural defenses, including adhesive, rapidly cleared mucus linings coating nearly all entry points to the body not covered by skin, has limited the effectiveness of drug and gene delivery by nanoscale delivery systems. Here, we investigate the use of muco-inert mucus-penetrating nanoparticles (MPP) for improving vaginal and gastrointestinal drug delivery. Conventional hydrophobic nanoparticles strongly adhere to mucus, facilitating rapid clearance from the body. Here, we demonstrate that mucoadhesive polystyrene nanoparticles (conventional nanoparticles, CP) become mucus-penetrating in human cervicovaginal mucus (CVM) after pretreatment with sufficient concentrations of Pluronic F127. Importantly, the diffusion rate of large MPP did not change in F127 pretreated CVM, implying there is no affect on the native pore structure of CVM. Additionally, there was no increase in inflammatory cytokine release in the vaginal tract of mice after daily application of 1% F127 for one week. Importantly, HSV virus remains adherent in F127-pretreated CVM. Mucosal epithelia use osmotic gradients for fluid absorption and secretion. We hypothesized that hypotonically-induced fluid uptake could be advantageous for rapidly delivering drugs through mucus to the vaginal epithelium. We evaluated hypotonic formulations for delivering water-soluble drugs and for drug delivery with MPP. Hypotonic formulations markedly increased the rate at which drugs and MPP reached the epithelial surface. Additionally, hypotonic formulations greatly enhanced drug and MPP delivery to the entire epithelial surface, including deep into the vaginal folds (rugae) that isotonic formulations

  14. Microsystems Technologies for Drug Delivery to the Inner Ear

    PubMed Central

    Leary Pararas, Erin E.; Borkholder, David A.; Borenstein, Jeffrey T.

    2012-01-01

    The inner ear represents one of the most technologically challenging targets for local drug delivery, but its clinical significance is rapidly increasing. The prevalence of sensorineural hearing loss and other auditory diseases, along with balance disorders and tinnitus, has spurred broad efforts to develop therapeutic compounds and regenerative approaches to treat these conditions, necessitating advances in systems capable of targeted and sustained drug delivery. The delicate nature of hearing structures combined with the relative inaccessibility of the cochlea by means of conventional delivery routes together necessitate significant advancements in both the precision and miniaturization of delivery systems, and the nature of the molecular and cellular targets for these therapies suggests that multiple compounds may need to be delivered in a time-sequenced fashion over an extended duration. Here we address the various approaches being developed for inner ear drug delivery, including micropump-based devices, reciprocating systems, and cochlear prosthesis-mediated delivery, concluding with an analysis of emerging challenges and opportunities for the first generation of technologies suitable for human clinical use. These developments represent exciting advances that have the potential to repair and regenerate hearing structures in millions of patients for whom no currently available medical treatments exist, a situation that requires them to function with electronic hearing augmentation devices or to live with severely impaired auditory function. These advances also have the potential for broader clinical applications that share similar requirements and challenges with the inner ear, such as drug delivery to the central nervous system. PMID:22386561

  15. Drug delivery strategies for the treatment of Helicobacter pylori infections.

    PubMed

    Conway, B R

    2005-01-01

    Helicobacter pylori is one of the most common pathogenic bacterial infections, colonising an estimated half of all humans. It is associated with the development of serious gastroduodenal disease - including peptic ulcers, gastric lymphoma and acute chronic gastritis. Current recommended regimes are not wholly effective and patient compliance, side-effects and bacterial resistance can be problematic. Drug delivery to the site of residence in the gastric mucosa may improve efficacy of the current and emerging treatments. Gastric retentive delivery systems potentially allow increased penetration of the mucus layer and therefore increased drug concentration at the site of action. Proposed gastric retentive systems for the enhancement of local drug delivery include floating systems, expandable or swellable systems and bioadhesive systems. Generally, problems with these formulations are lack of specificity, limited to mucus turnover or failure to persist in the stomach. Gastric mucoadhesive systems are hailed as a promising technology to address this issue, penetrating the mucus layer and prolonging activity at the mucus-epithelial interface. This review appraises gastroretentive delivery strategies specifically with regard to their application as a delivery system to target Helicobacter. As drug-resistant strains emerge, the development of a vaccine to eradicate and prevent reinfection is an attractive proposition. Proposed prophylactic and therapeutic vaccines have been delivered using a number of mucosal routes using viral and non-viral vectors. The delivery form, inclusion of adjuvants, and delivery regime will influence the immune response generated. PMID:15777232

  16. Discovery and Delivery of Synergistic Chemotherapy Drug Combinations to Tumors

    NASA Astrophysics Data System (ADS)

    Camacho, Kathryn Militar

    Chemotherapy combinations for cancer treatments harbor immense therapeutic potentials which have largely been untapped. Of all diseases, clinical studies of drug combinations are the most prevalent in oncology, yet their effectiveness is disputable, as complete tumor regressions are rare. Our research has been devoted towards developing delivery vehicles for combinations of chemotherapy drugs which elicit significant tumor reduction yet limit toxicity in healthy tissue. Current administration methods assume that chemotherapy combinations at maximum tolerable doses will provide the greatest therapeutic effect -- a presumption which often leads to unprecedented side effects. Contrary to traditional administration, we have found that drug ratios rather than total cumulative doses govern combination therapeutic efficacy. In this thesis, we have developed nanoparticles to incorporate synergistic ratios of chemotherapy combinations which significantly inhibit cancer cell growth at lower doses than would be required for their single drug counterparts. The advantages of multi-drug incorporation in nano-vehicles are many: improved accumulation in tumor tissue via the enhanced permeation and retention effect, limited uptake in healthy tissue, and controlled exposure of tumor tissue to optimal synergistic drug ratios. To exploit these advantages for polychemotherapy delivery, two prominent nanoparticles were investigated: liposomes and polymer-drug conjugates. Liposomes represent the oldest class of nanoparticles, with high drug loading capacities and excellent biocompatibility. Polymer-drug conjugates offer controlled drug incorporations through reaction stoichiometry, and potentially allow for delivery of precise ratios. Here, we show that both vehicles, when armed with synergistic ratios of chemotherapy drugs, significantly inhibit tumor growth in an aggressive mouse breast carcinoma model. Furthermore, versatile drug incorporation methods investigated here can be broadly

  17. Mucoadhesive and thermogelling systems for vaginal drug delivery.

    PubMed

    Caramella, Carla M; Rossi, Silvia; Ferrari, Franca; Bonferoni, Maria Cristina; Sandri, Giuseppina

    2015-09-15

    This review focuses on two formulation approaches, mucoadhesion and thermogelling, intended for prolonging residence time on vaginal mucosa of medical devices or drug delivery systems, thus improving their efficacy. The review, after a brief description of the vaginal environment and, in particular, of the vaginal secretions that strongly affect in vivo performance of vaginal formulations, deals with the above delivery systems. As for mucoadhesive systems, conventional formulations (gels, tablets, suppositories and emulsions) and novel drug delivery systems (micro-, nano-particles) intended for vaginal administration to achieve either local or systemic effect are reviewed. As for thermogelling systems, poly(ethylene oxide-propylene oxide-ethylene oxide) copolymer-based and chitosan-based formulations are discussed as thermogelling systems. The methods employed for functional characterization of both mucoadhesive and thermogelling drug delivery systems are also briefly described. PMID:25683694

  18. Membrane-targeting liquid crystal nanoparticles (LCNPs) for drug delivery

    NASA Astrophysics Data System (ADS)

    Nag, Okhil K.; Naciri, Jawad; Spillmann, Christopher M.; Delehanty, James B.

    2016-03-01

    In addition to maintaining the structural integrity of the cell, the plasma membrane regulates multiple important cellular processes, such as endocytosis and trafficking, apoptotic pathways and drug transport. The modulation or tracking of such cellular processes by means of controlled delivery of drugs or imaging agents via nanoscale delivery systems is very attractive. Nanoparticle-mediated delivery systems that mediate long-term residence (e.g., days) and controlled release of the cargoes in the plasma membrane while simultaneously not interfering with regular cellular physiology would be ideal for this purpose. Our laboratory has developed a plasma membrane-targeted liquid crystal nanoparticle (LCNP) formulation that can be loaded with dyes or drugs which can be slowly released from the particle over time. Here we highlight the utility of these nanopreparations for membrane delivery and imaging.

  19. Recent Applications of Liposomes in Ophthalmic Drug Delivery

    PubMed Central

    Mishra, Gyan P.; Bagui, Mahuya; Tamboli, Viral; Mitra, Ashim K.

    2011-01-01

    Liposomal formulations were significantly explored over the last decade for the ophthalmic drug delivery applications. These formulations are mainly composed of phosphatidylcholine (PC) and other constituents such as cholesterol and lipid-conjugated hydrophilic polymers. Liposomes are biodegradable and biocompatible in nature. Current approaches for topical delivery of liposomes are focused on improving the corneal adhesion and permeation by incorporating various bioadhesive and penetration enhancing polymers. In the case of posterior segment disorders improvement in intravitreal half life and targeted drug delivery to the retina is achieved by liposomes. In this paper we have attempted to summarize the applications of liposomes in the field of ophthalmic drug delivery by citing numerous investigators over the last decade. PMID:21490757

  20. Coaxial electrohydrodynamic atomization: microparticles for drug delivery applications.

    PubMed

    Davoodi, Pooya; Feng, Fang; Xu, Qingxing; Yan, Wei-Cheng; Tong, Yen Wah; Srinivasan, M P; Sharma, Vijay Kumar; Wang, Chi-Hwa

    2015-05-10

    As cancer takes its toll on human health and well-being, standard treatment techniques such as chemotherapy and radiotherapy often fall short of ideal solutions. In particular, adverse side effects due to excess dosage and collateral damage to healthy cells as well as poor patient compliance due to multiple administrations continue to pose challenges in cancer treatment. Thus, the development of appropriately engineered drug delivery systems (DDS) for effective, controlled and sustained delivery of drugs is of interest for patient treatment. Moreover, the physiopathological characteristics of tumors play an essential role in the success of cancer treatment. Here, we present an overview of the application of double-walled microparticles for local drug delivery with particular focus on the electrohydrodynamic atomization (EHDA) technique and its fabrication challenges. The review highlights the importance of a combination of experimental data and computational simulations for the design of an optimal delivery system. PMID:25483422

  1. An Intravaginal Ring for the Simultaneous Delivery of Multiple Drugs

    PubMed Central

    Baum, Marc M.; Butkyavichene, Irina; Gilman, Joshua; Kennedy, Sean; Kopin, Etana; Malone, Amanda M.; Nguyen, Cali; Smith, Thomas J.; Friend, David R.; Clark, Meredith R.; Moss, John A.

    2013-01-01

    Intravaginal delivery of microbicide combinations is a promising approach for the prevention of sexually transmitted infections, but requires a method of providing simultaneous, independent release of multiple agents into the vaginal compartment. A novel intravaginal ring (IVR) platform has been developed for simultaneous delivery of the reverse-transcriptase inhibitor tenofovir (TFV) and the guanosine analogue antiviral acyclovir (ACV) with independent control of release rate for each drug. The IVR is based on a pod design, with up to 10 individual polymer-coated drug cores embedded in the ring releasing through preformed delivery channels. The release rate from each pod is controlled independently of the others by the drug properties, polymer coating, and size and number of delivery channels. Pseudo-zero-order in vitro release of TFV (144 ± 10 µg day) and ACV (120 ± 19 µg day−1) from an IVR containing both drugs was sustained for 28 days. The mechanical properties of the pod IVR were evaluated and compared with the commercially available Estring® (Pfizer, NY, NY). The pod-IVR design enables the vaginal delivery of multiple microbicides with differing physicochemical properties, and is an attractive approach for the sustained intravaginal delivery of relatively hydrophilic drugs that are difficult to deliver using conventional matrix IVR technology. PMID:22619076

  2. Micro-Fluidic Device for Drug Delivery

    NASA Technical Reports Server (NTRS)

    Beebe, David J. (Inventor); MacDonald, Michael J. (Inventor); Eddington, David T. (Inventor); Mensing, Glennys A. (Inventor)

    2014-01-01

    A microfluidic device is provided for delivering a drug to an individual. The microfluidic device includes a body that defines a reservoir for receiving the drug therein. A valve interconnects the reservoir to an output needle that is insertable into the skin of an individual. A pressure source urges the drug from the reservoir toward the needle. The valve is movable between a closed position preventing the flow of the drug from the reservoir to the output needle and an open position allowing for the flow of the drug from the reservoir to the output needle in response to a predetermined condition in the physiological fluids of the individual.

  3. Aptamer-Gated Nanoparticles for Smart Drug Delivery

    PubMed Central

    Ozalp, Veli Cengiz; Eyidogan, Fusun; Oktem, Huseyin Avni

    2011-01-01

    Aptamers are functional nucleic acid sequences which can bind specific targets. An artificial combinatorial methodology can identify aptamer sequences for any target molecule, from ions to whole cells. Drug delivery systems seek to increase efficacy and reduce side-effects by concentrating the therapeutic agents at specific disease sites in the body. This is generally achieved by specific targeting of inactivated drug molecules. Aptamers which can bind to various cancer cell types selectively and with high affinity have been exploited in a variety of drug delivery systems for therapeutic purposes. Recent progress in selection of cell-specific aptamers has provided new opportunities in targeted drug delivery. Especially functionalization of nanoparticles with such aptamers has drawn major attention in the biosensor and biomedical areas. Moreover, nucleic acids are recognized as an attractive building materials in nanomachines because of their unique molecular recognition properties and structural features. A active controlled delivery of drugs once targeted to a disease site is a major research challenge. Stimuli-responsive gating is one way of achieving controlled release of nanoparticle cargoes. Recent reports incorporate the structural properties of aptamers in controlled release systems of drug delivering nanoparticles. In this review, the strategies for using functional nucleic acids in creating smart drug delivery devices will be explained. The main focus will be on aptamer-incorporated nanoparticle systems for drug delivery purposes in order to assess the future potential of aptamers in the therapeutic area. Special emphasis will be given to the very recent progress in controlled drug release based on molecular gating achieved with aptamers.

  4. Coordination polymer particles as potential drug delivery systems.

    PubMed

    Imaz, Inhar; Rubio-Martínez, Marta; García-Fernández, Lorena; García, Francisca; Ruiz-Molina, Daniel; Hernando, Jordi; Puntes, Victor; Maspoch, Daniel

    2010-07-14

    Micro- and nanoscale coordination polymer particles can be used for encapsulating and delivering drugs. In vitro cancer cell cytotoxicity assays showed that these capsules readily release doxorubicin, which shows anticancer efficacy. The results from this work open up new avenues for metal-organic capsules to be used as potential drug delivery systems. PMID:20485835

  5. Liposomes in topical ophthalmic drug delivery: an update.

    PubMed

    Agarwal, Renu; Iezhitsa, Igor; Agarwal, Puneet; Abdul Nasir, Nurul Alimah; Razali, Norhafiza; Alyautdin, Renad; Ismail, Nafeeza Mohd

    2016-05-01

    Topical route of administration is the most commonly used method for the treatment of ophthalmic diseases. However, presence of several layers of permeation barriers starting from the tear film till the inner layers of cornea make it difficult to achieve the therapeutic concentrations in the target tissue within the eye. In order to circumvent these barriers and to provide sustained and targeted drug delivery, tremendous advances have been made in developing efficient and safe drug delivery systems. Liposomes due to their unique structure prove to be extremely beneficial drug carriers as they can entrap both the hydrophilic and hydrophobic drugs. The conventional liposomes had several drawbacks particularly their tendency to aggregate, the instability and leakage of entrapped drug and susceptibility to phagocytosis. Due to this reason, for a long time, liposomes as drug delivery systems did not attract much attention of researchers and clinicians. However, over recent years development of new generation liposomes has opened up new approaches for targeted and sustained drug delivery using liposomes and has rejuvenated the interest of researchers in this field. In this review we present a summary of current literature to understand the anatomical and physiological limitation in achieving adequate ocular bioavailability of topically applied drugs and utility of liposomes in overcoming these limitations. The recent developments related to new generation liposomes are discussed. PMID:25116511

  6. Basics and recent advances in peptide and protein drug delivery

    PubMed Central

    Bruno, Benjamin J; Miller, Geoffrey D; Lim, Carol S

    2014-01-01

    While the peptide and protein therapeutic market has developed significantly in the past decades, delivery has limited their use. Although oral delivery is preferred, most are currently delivered intravenously or subcutaneously due to degradation and limited absorption in the gastrointestinal tract. Therefore, absorption enhancers, enzyme inhibitors, carrier systems and stability enhancers are being studied to facilitate oral peptide delivery. Additionally, transdermal peptide delivery avoids the issues of the gastrointestinal tract, but also faces absorption limitations. Due to proteases, opsonization and agglutination, free peptides are not systemically stable without modifications. This review discusses oral and transdermal peptide drug delivery, focusing on barriers and solutions to absorption and stability issues. Methods to increase systemic stability and site-specific delivery are also discussed. PMID:24228993

  7. Determination of chemotherapeutic drugs in human urine by capillary electrophoresis with UV and fluorimetric detection using solid-supported liquid-liquid extraction for sample clean-up.

    PubMed

    Hurtado-Sánchez, María del Carmen; Acedo-Valenzuela, María Isabel; Durán-Merás, Isabel; Rodríguez-Cáceres, María Isabel

    2015-06-01

    Capillary electrophoresis was used for the rapid determination of three chemotherapeutic drugs employed to treat colorectal cancer: irinotecan, tegafur, and leucovorin, and their main metabolites (7-ethyl-10-hydroxycamptothecin and 5-fluorouracil), in human urine samples. A phosphate buffer (pH 11.34; 20 mM) was selected as the background electrolyte. A hydrodynamic injection (9 s, 30 mbar) was applied and the separation was carried out using a separation temperature and voltage of 25°C and 25 kV, respectively. A capillary with two detection windows for serial online UV and fluorescence detection was satisfactorily employed. A solid-supported liquid-liquid extraction procedure was optimized for the clean-up of the urine samples and the extraction of the analytes. Matrix effects were assessed and signal suppression was observed for three of the analytes, thus, matrix-matched calibration was used for compensating residual matrix effects on these analytes. The proposed method allows the separation and quantification of the chemotherapeutics in less than 6 min. Detection limits range between 0.01 and 0.30 mg/L. The method was satisfactorily applied to the determination of the target compounds in human urine samples, with recoveries of 92.4-107.7%. PMID:25820908

  8. Strategies for Enhanced Drug Delivery to the Central Nervous System

    PubMed Central

    Dwibhashyam, V. S. N. M.; Nagappa, A. N.

    2008-01-01

    Treating central nervous system diseases is very challenging because of the presence of a variety of formidable obstacles that impede drug delivery. Physiological barriers like the blood-brain barrier and blood-cerebrospinal fluid barrier as well as various efflux transporter proteins make the entry of drugs into the central nervous system very difficult. The present review provides a brief account of the blood brain barrier, the P-glycoprotein efflux and various strategies for enhancing drug delivery to the central nervous system. PMID:20046703

  9. Stabilized Heptapeptide A7R for Enhanced Multifunctional Liposome-Based Tumor-Targeted Drug Delivery.

    PubMed

    Ying, Man; Shen, Qing; Liu, Yu; Yan, Zhiqiang; Wei, Xiaoli; Zhan, Changyou; Gao, Jie; Xie, Cao; Yao, Bingxin; Lu, Weiyue

    2016-06-01

    (L)A7R (ATWLPPR) is a heptapeptide with high binding affinity in vitro to vascular endothelial growth factor receptor 2 (VEGFR2) and neuropilin-1 (NRP-1) overexpressed on glioma, glioma vasculogenic mimicry and neovasculature. However, its tumor targeting efficacy is significantly reduced in vivo due to proteolysis in blood circulation. To improve the in vivo stability and targeting efficacy, the retro inverso isomer of (L)A7R ((D)A7R) was developed for glioma-targeted drug delivery. (D)A7R was expected to have a similar binding affinity to its receptors in vitro (VEGFR2 and NRP-1), which was experimentally confirmed. In vivo, (D)A7R-modified liposomes achieved improved glioma-targeted efficiency than did (L)A7R-modified liposomes. After loading a chemotherapeutic agent (doxorubicin), (D)A7R-modified liposomes significantly inhibited subcutaneous model tumor in comparison to free doxorubicin, plain liposomes and (L)A7R-modified liposomes. In summary, the present study presented the potential of a proteolytically stable d-peptide ligand for in vivo tumor-targeted drug delivery. PMID:27195531

  10. Effect of Chemotherapeutic Drugs on Caspase-3 Activity, as a Key Biomarker for Apoptosis in Ovarian Tumor Cell Cultured as Monolayer. A Pilot Study

    PubMed Central

    Gregoraszczuk, Ewa L; Rak-Mardyła, Agnieszka; Ryś, Janusz; Jakubowicz, Jerzy; Urbański, Krzysztof

    2015-01-01

    We aimed to develop a cost-effective and robust method to predict drug resistance in individual patients. Representative tissue fragments were obtained from tumors removed from female patients, aged 24-74 years old. The tumor tissue was taken by a histopathology’s or a surgeon under sterile conditions. Cells obtained by enzymatic dissociation from tumor after surgery, were cultured as a monolayer for 6 days. Paclitaxel, doxorubicin, carboplatin and endoxan alone or in combination were added at the beginning of culture and after 6 days, Alamar blue test was used for showing action on cell proliferation why caspase- 3 activity assays for verifying action on apoptosis. Inhibitory action on cell proliferation was noted in 2 of 12 patients tumor treated with both single and combined drugs. Using caspase-3 assay we showed that 50% of tumor cells was resistant to single chemotherapeutic drugs and 40% for combined. In 2 of 12 tumors, which did not reacted on single drugs, positive synergistic action on cell proliferation was observed in combination of D + E and C + E. This pilot study suggests: 1) monolayer culture of tumor cells, derived from individual patients, before chemotherapy could provide a suitable model for studying resistance for drugs; 2) caspase-3 activity is cheap and useful methods; 3) Alamar blue test should be taken into consideration for measuring cell proliferation. PMID:26664382

  11. Recent advances in liposome surface modification for oral drug delivery.

    PubMed

    Nguyen, Thanh Xuan; Huang, Lin; Gauthier, Mario; Yang, Guang; Wang, Qun

    2016-05-01

    Oral delivery via the gastrointestinal (GI) tract is the dominant route for drug administration. Orally delivered liposomal carriers can enhance drug solubility and protect the encapsulated theraputic agents from the extreme conditions found in the GI tract. Liposomes, with their fluid lipid bilayer membrane and their nanoscale size, can significantly improve oral absorption. Unfortunately, the clinical applications of conventional liposomes have been hindered due to their poor stability and availability under the harsh conditions typically presented in the GI tract. To overcome this problem, the surface modification of liposomes has been investigated. Although liposome surface modification has been extensively studied for oral drug delivery, no review exists so far that adequately covers this topic. The purpose of this paper is to summarize and critically analyze emerging trends in liposome surface modification for oral drug delivery. PMID:27074098

  12. Micro and nanoparticle drug delivery systems for preventing allotransplant rejection.

    PubMed

    Fisher, James D; Acharya, Abhinav P; Little, Steven R

    2015-09-01

    Despite decades of advances in transplant immunology, tissue damage caused by acute allograft rejection remains the primary cause of morbidity and mortality in the transplant recipient. Moreover, the long-term sequelae of lifelong immunosuppression leaves patients at risk for developing a host of other deleterious conditions. Controlled drug delivery using micro- and nanoparticles (MNPs) is an effective way to deliver higher local doses of a given drug to specific tissues and cells while mitigating systemic effects. Herein, we review several descriptions of MNP immunotherapies aimed at prolonging allograft survival. We also discuss developments in the field of biomimetic drug delivery that use MNP constructs to induce and recruit our bodies' own suppressive immune cells. Finally, we comment on the regulatory pathway associated with these drug delivery systems. Collectively, it is our hope the studies described in this review will help to usher in a new era of immunotherapy in organ transplantation. PMID:25937032

  13. Design of Nanoparticle-Based Carriers for Targeted Drug Delivery

    PubMed Central

    Ren, Muqing; Duval, Kayla; Guo, Xing; Chen, Zi

    2016-01-01

    Nanoparticles have shown promise as both drug delivery vehicles and direct antitumor systems, but they must be properly designed in order to maximize efficacy. Computational modeling is often used both to design new nanoparticles and to better understand existing ones. Modeled processes include the release of drugs at the tumor site and the physical interaction between the nanoparticle and cancer cells. In this article, we provide an overview of three different targeted drug delivery methods (passive targeting, active targeting and physical targeting), compare methods of action, advantages, limitations, and the current stage of research. For the most commonly used nanoparticle carriers, fabrication methods are also reviewed. This is followed by a review of computational simulations and models on nanoparticle-based drug delivery. PMID:27398083

  14. Tissue Bioeffects during Ultrasound-mediated Drug Delivery

    NASA Astrophysics Data System (ADS)

    Sutton, Jonathan

    Ultrasound has been developed as both a valuable diagnostic tool and a potent promoter of beneficial tissue bioeffects for the treatment of cardiovascular disease. Vascular effects can be mediated by mechanical oscillations of circulating microbubbles, or ultrasound contrast agents, which may also encapsulate and shield a therapeutic agent in the bloodstream. Oscillating microbubbles can create stresses directly on nearby tissue or induce fluid effects that effect drug penetration into vascular tissue, lyse thrombi, or direct drugs to optimal locations for delivery. These investigations have spurred continued research into alternative therapeutic applications, such as bioactive gas delivery. This dissertation addresses a fundamental hypothesis in biomedical ultrasound: ultrasound-mediated drug delivery is capable of increasing the penetration of drugs across different physiologic barriers within the cardiovascular system, such as the vascular endothelium, blood clots, and smooth muscle cells.

  15. Crystallization Methods for Preparation of Nanocrystals for Drug Delivery System.

    PubMed

    Gao, Yuan; Wang, Jingkang; Wang, Yongli; Yin, Qiuxiang; Glennon, Brian; Zhong, Jian; Ouyang, Jinbo; Huang, Xin; Hao, Hongxun

    2015-01-01

    Low water solubility of drug products causes delivery problems such as low bioavailability. The reduced particle size and increased surface area of nanocrystals lead to the increasing of the dissolution rate. The formulation of drug nanocrystals is a robust approach and has been widely applied to drug delivery system (DDS) due to the significant development of nanoscience and nanotechnology. It can be used to improve drug efficacy, provide targeted delivery and minimize side-effects. Crystallization is the main and efficient unit operation to produce nanocrystals. Both traditional crystallization methods such as reactive crystallization, anti-solvent crystallization and new crystallization methods such as supercritical fluid crystallization, high-gravity controlled precipitation can be used to produce nanocrystals. The current mini-review outlines the main crystallization methods addressed in literature. The advantages and disadvantages of each method were summarized and compared. PMID:26027573

  16. Biodegradation-tunable mesoporous silica nanorods for controlled drug delivery.

    PubMed

    Park, Sung Bum; Joo, Young-Ho; Kim, Hyunryung; Ryu, WonHyoung; Park, Yong-il

    2015-05-01

    Mesoporous silica in the forms of micro- or nanoparticles showed great potentials in the field of controlled drug delivery. However, for precision control of drug release from mesoporous silica-based delivery systems, it is critical to control the rate of biodegradation. Thus, in this study, we demonstrate a simple and robust method to fabricate "biodegradation-tunable" mesoporous silica nanorods based on capillary wetting of anodic aluminum oxide (AAO) template with an aqueous alkoxide precursor solution. The porosity and nanostructure of silica nanorods were conveniently controlled by adjusting the water/alkoxide molar ratio of precursor solutions, heat-treatment temperature, and Na addition. The porosity and biodegradation kinetics of the fabricated mesoporous nanorods were analyzed using N2 adsorption/desorption isotherm, TGA, DTA, and XRD. Finally, the performance of the mesoporous silica nanorods as drug delivery carrier was demonstrated with initial burst and subsequent "zero-order" release of anti-cancer drug, doxorubicin. PMID:25746247

  17. Smart surface-enhanced Raman scattering traceable drug delivery systems.

    PubMed

    Liu, Lei; Tang, Yonghong; Dai, Sheng; Kleitz, Freddy; Qiao, Shi Zhang

    2016-07-01

    A novel smart nanoparticle-based system has been developed for tracking intracellular drug delivery through surface-enhanced Raman scattering (SERS). This new drug delivery system (DDS) shows targeted cytotoxicity towards cancer cells via pH-cleavable covalent carboxylic hydrazone links and the SERS tracing capability based on gold@silica nanocarriers. Doxorubicin, as a model anticancer drug, was employed to compare SERS with conventional fluorescence tracing approaches. It is evident that SERS demonstrates higher sensitivity and resolution, revealing intracellular details, as the strengths of the original Raman signals can be amplified by SERS. Importantly, non-destructive SERS will provide the designed DDS with great autonomy and potential to study the dynamic procedures of non-fluorescent drug delivery into living cells. PMID:27297745

  18. Numerical simulation of iontophoresis in the drug delivery system.

    PubMed

    Filipovic, Nenad; Zivanovic, Marko; Savic, Andrej; Bijelic, Goran

    2016-01-01

    The architecture and composition of stratum corneum act as barriers and limit the diffusion of most drug molecules and ions. Much effort has been made to overcome this barrier and it can be seen that iontophoresis has shown a good effect. Iontophoresis represents the application of low electrical potential to increase the transport of drugs into and across the skin or tissue. Iontophoresis is a noninvasive drug delivery system, and therefore, it is a useful alternative to drug transportation by injection. In this study, we present a numerical model and effects of electrical potential on the drug diffusion in the buccal tissue and the stratum corneum. The initial numerical results are in good comparison with experimental observation. We demonstrate that the application of an applied voltage can greatly improve the efficacy of localized drug delivery as compared to diffusion alone. PMID:26592537

  19. Targeting tumor metastases: drug delivery mechanisms and technologies

    PubMed Central

    Ganapathy, Vidya; Moghe, Prabhas V.; Roth, Charles M.

    2016-01-01

    Primary sites of tumor are the focal triggers of cancers, yet it is the subsequent metastasis events that cause the majority of the morbidity and mortality. Metastatic tumor cells exhibit a phenotype that differs from that of the parent cells, as they represent a resistant, invasive subpopulation of the original tumor, may have acquired additional genetic or epigenetic alterations under exposure to prior chemotherapeutic or radiotherapeutic treatments, and reside in a microenvironment differing from that of its origin. This combination of resistant phenotype and distal location make tracking and treating metastases particularly challenging. In this review, we highlight some of the unique biological traits of metastasis, which in turn, inspire emerging strategies for targeted imaging of metastasized tumors and metastasis-directed delivery of therapeutics. PMID:26409123

  20. Smart surface-enhanced Raman scattering traceable drug delivery systems

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Tang, Yonghong; Dai, Sheng; Kleitz, Freddy; Qiao, Shi Zhang

    2016-06-01

    A novel smart nanoparticle-based system has been developed for tracking intracellular drug delivery through surface-enhanced Raman scattering (SERS). This new drug delivery system (DDS) shows targeted cytotoxicity towards cancer cells via pH-cleavable covalent carboxylic hydrazone links and the SERS tracing capability based on gold@silica nanocarriers. Doxorubicin, as a model anticancer drug, was employed to compare SERS with conventional fluorescence tracing approaches. It is evident that SERS demonstrates higher sensitivity and resolution, revealing intracellular details, as the strengths of the original Raman signals can be amplified by SERS. Importantly, non-destructive SERS will provide the designed DDS with great autonomy and potential to study the dynamic procedures of non-fluorescent drug delivery into living cells.A novel smart nanoparticle-based system has been developed for tracking intracellular drug delivery through surface-enhanced Raman scattering (SERS). This new drug delivery system (DDS) shows targeted cytotoxicity towards cancer cells via pH-cleavable covalent carboxylic hydrazone links and the SERS tracing capability based on gold@silica nanocarriers. Doxorubicin, as a model anticancer drug, was employed to compare SERS with conventional fluorescence tracing approaches. It is evident that SERS demonstrates higher sensitivity and resolution, revealing intracellular details, as the strengths of the original Raman signals can be amplified by SERS. Importantly, non-destructive SERS will provide the designed DDS with great autonomy and potential to study the dynamic procedures of non-fluorescent drug delivery into living cells. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr03869g

  1. Current pharmaceutical design on adhesive based transdermal drug delivery systems.

    PubMed

    Ghosh, Animesh; Banerjee, Subham; Kaity, Santanu; Wong, Tin W

    2015-01-01

    Drug-in-adhesive transdermal drug delivery matrix exploits intimate contact of the carrier with stratum corneum, the principal skin barrier to drug transport, to deliver the actives across the skin and into the systemic circulation. The main application challenges of drug-in-adhesive matrix lie in the physicochemical properties of skin varying with age, gender, ethnicity, health and environmental condition of patients. This in turn poses difficulty to design a universal formulation to meet the intended adhesiveness, drug release and drug permeation performances. This review focuses on pressure-sensitive adhesives, and their adhesiveness and drug release/permeation modulation mechanisms as a function of adhesive molecular structure and formulation attributes. It discusses approaches to modulate adhesive tackiness, strength, elasticity, hydrophilicity, molecular suspension capability and swelling capacity, which contribute to the net effect of adhesive on skin bonding, drug release and drug permeation. PMID:25925119

  2. Silk Fibroin-Based Nanoparticles for Drug Delivery

    PubMed Central

    Zhao, Zheng; Li, Yi; Xie, Mao-Bin

    2015-01-01

    Silk fibroin (SF) is a protein-based biomacromolecule with excellent biocompatibility, biodegradability and low immunogenicity. The development of SF-based nanoparticles for drug delivery have received considerable attention due to high binding capacity for various drugs, controlled drug release properties and mild preparation conditions. By adjusting the particle size, the chemical structure and properties, the modified or recombinant SF-based nanoparticles can be designed to improve the therapeutic efficiency of drugs encapsulated into these nanoparticles. Therefore, they can be used to deliver small molecule drugs (e.g., anti-cancer drugs), protein and growth factor drugs, gene drugs, etc. This paper reviews recent progress on SF-based nanoparticles, including chemical structure, properties, and preparation methods. In addition, the applications of SF-based nanoparticles as carriers for therapeutic drugs are also reviewed. PMID:25749470

  3. Insights into drug delivery across the nail plate barrier.

    PubMed

    Saner, Manish V; Kulkarni, Abhijeet D; Pardeshi, Chandrakantsing V

    2014-11-01

    Topical therapy is at the forefront in treating nail ailments (especially onychomycosis and nail psoriasis) due to its local effects, which circumvents systemic adverse events, improves patient compliance and reduces treatment cost. However, the success of topical therapy has been hindered due to poor penetration of topical therapeutics across densely keratinized nail plate barrier. For effective topical therapy across nail plate, ungual drug permeation must be enhanced. Present review is designed to provide an insight into prime aspects of transungual drug delivery viz. nail structure and physiology, various onychopathies, techniques of nail permeation enhancement and in vitro models for trans-nail drug permeation studies. Updated list of drug molecules studied across the nail plate and key commercial products have been furnished with sufficient depth. Patents pertinent to, and current clinical status of transungual drug delivery have also been comprehensively reviewed. This is the first systematic critique encompassing the detailed aspects of transungual drug delivery. In our opinion, transungual drug delivery is a promising avenue for researchers to develop novel formulations, augmenting pharmaceutical industries to commercialize the products for nail disorders. PMID:24964054

  4. Using DNA nanotechnology to produce a drug delivery system

    NASA Astrophysics Data System (ADS)

    Huyen La, Thi; Thu Thuy Nguyen, Thi; Phuc Pham, Van; Huyen Nguyen, Thi Minh; Huan Le, Quang

    2013-03-01

    Drug delivery to cancer cells in chemotherapy is one of the most advanced research topics. The effectiveness of the current cancer treatment drugs is limited because they are not capable of distinguishing between cancer cells and normal cells so that they kill not only cancer cells but also normal ones. To overcome this disadvantage by profiting from the differences in physical and chemical properties between cancer and normal cells, nanoparticles (NPs) delivering a drug are designed in a specific manner such that they can distinguish the cancer cells from the normal ones and are targeted only to the cancer cells. Currently, there are various drug delivery systems with many advantages, but sharing some common disadvantages such as difficulty with controlling the size, low encapsulation capacity and low stability. With the development and success of DNA nanotechnology, DNA strands are used to create effective drug delivery NPs with precisely controlled size and structure, safety and high stability. This article presents our study on drug encapsulation in DNA nanostructure which loaded docetaxel and curcumin in a desire to create a new and effective drug delivery system with high biological compatibility. Invited talk at the 6th International Workshop on Advanced Materials Science and Nanotechnology, 30 October-2 November, 2012, Ha Long, Vietnam.

  5. An emerging platform for drug delivery: aerogel based systems.

    PubMed

    Ulker, Zeynep; Erkey, Can

    2014-03-10

    Over the past few decades, advances in "aerogel science" have provoked an increasing interest for these materials in pharmaceutical sciences for drug delivery applications. Because of their high surface areas, high porosities and open pore structures which can be tuned and controlled by manipulation of synthesis conditions, nanostructured aerogels represent a promising class of materials for delivery of various drugs as well as enzymes and proteins. Along with biocompatible inorganic aerogels and biodegradable organic aerogels, more complex systems such as surface functionalized aerogels, composite aerogels and layered aerogels have also been under development and possess huge potential. Emphasis is given to the details of the aerogel synthesis and drug loading methods as well as the influence of synthesis parameters and loading methods on the adsorption and release of the drugs. Owing to their ability to increase the bioavailability of low solubility drugs, to improve both their stability and their release kinetics, there are an increasing number of research articles concerning aerogels in different drug delivery applications. This review presents an up to date overview of the advances in all kinds of aerogel based drug delivery systems which are currently under investigation. PMID:24394377

  6. Dissolving microneedles for transdermal drug delivery.

    PubMed

    Lee, Jeong W; Park, Jung-Hwan; Prausnitz, Mark R

    2008-05-01

    Microfabrication technology has been adapted to produce micron-scale needles as a safer and painless alternative to hypodermic needle injection, especially for protein biotherapeutics and vaccines. This study presents a design that encapsulates molecules within microneedles that dissolve within the skin for bolus or sustained delivery and leave behind no biohazardous sharp medical waste. A fabrication process was developed based on casting a viscous aqueous solution during centrifugation to fill a micro-fabricated mold with biocompatible carboxymethylcellulose or amylopectin formulations. This process encapsulated sulforhodamine B, bovine serum albumin, and lysozyme; lysozyme was shown to retain full enzymatic activity after encapsulation and to remain 96% active after storage for 2 months at room temperature. Microneedles were also shown to be strong enough to insert into cadaver skin and then to dissolve within minutes. Bolus delivery was achieved by encapsulating molecules just within microneedle shafts. For the first time, sustained delivery over hours to days was achieved by encapsulating molecules within the microneedle backing, which served as a controlled release reservoir that delivered molecules by a combination of swelling the backing with interstitial fluid drawn out of the skin and molecule diffusion into the skin via channels formed by dissolved microneedles. We conclude that dissolving microneedles can be designed to gently encapsulate molecules, insert into skin, and enable bolus or sustained release delivery. PMID:18261792

  7. A look at emerging delivery systems for topical drug products.

    PubMed

    Fireman, Sharon; Toledano, Ofer; Neimann, Karine; Loboda, Natalia; Dayan, Nava

    2011-01-01

    The introduction of new topical drugs based on new chemical entities has become a rare event. Instead, pharmaceutical companies have been focused on reformulating existing drugs resulting in an ever-growing number of topical drug products for every approved drug substance. In light of this trend, soon reformulations may not be as rewarding to their sponsors as they are today unless they offer a substantial improvement over other formulations of the same drug substance and the same indication, namely improved efficacy over existing drugs, reduced side effects, unique drug combinations, or applicability for new indications. This article reviews and compares topical drug delivery systems currently under active research that are designed to offer such advantages in the coming years. The reviewed delivery systems are: liposomes, niosomes, transferosomes, ethosomes, solid lipid nanoparticles, nanostructured lipid carriers, cyclodextrin, and sol-gel microcapsules. Among all the topical drug delivery systems currently undergoing active research, only the sol-gel microencapsulation is at clinical stages. PMID:22353154

  8. Targeted Cellular Drug Delivery using Tailored Dendritic Nanostructures

    NASA Astrophysics Data System (ADS)

    Kannan, Rangaramanujam; Kolhe, Parag; Kannan, Sujatha; Lieh-Lai, Mary

    2002-03-01

    Dendrimers and hyperbranched polymers possess highly branched architectures, with a large number of controllable, tailorble, ‘peripheral’ functionalities. Since the surface chemistry of these materials can be modified with relative ease, these materials have tremendous potential in targeted drug and gene delivery. The large number of end groups can also be tailored to create special affinity to targeted cells, and can also encapsulate drugs and deliver them in a controlled manner. We are developing tailor-modified dendritic systems for drug delivery. Synthesis, in-vitro drug loading, in-vitro drug delivery, and the targeting efficiency to the cell are being studied systematically using a wide variety of experimental tools. Polyamidoamine and Polyol dendrimers, with different generations and end-groups are studied, with drugs such as Ibuprofen and Methotrexate. Our results indicate that a large number of drug molecules can be encapsulated/attached to the dendrimers, depending on the end groups. The drug-encapsulated dendrimer is able to enter the cells rapidly and deliver the drug. Targeting strategies being explored

  9. Novel non-invasive protein and peptide drug delivery approaches.

    PubMed

    Wallis, L; Kleynhans, E; Toit, T Du; Gouws, C; Steyn, D; Steenekamp, J; Viljoen, J; Hamman, J

    2014-01-01

    Protein and peptide based therapeutics are typically administered by injection due to their poor uptake when administered via enteral routes of drug administration. Unfortunately, chronic administration of these drugs through multiple injections presents certain patient related problems and it is difficult to mimic the normal physiological release patterns via this mode of drug administration. A need therefore exists to non-invasively deliver these drugs by means of alternative ways such as via the oral, pulmonary, nasal, transdermal and buccal administration routes. Although some attempts of needle free peptide and protein drug delivery have progressed to the clinical stage, relatively limited success has been achieved in terms of commercially available products. Despite the low frequency of clinical breakthroughs with noninvasive protein drug delivery this far, it remains an active research area with renewed interest not only due to its improved therapeutic potential, but also due to the attractive commercial outcomes it offers. It is the aim of this review article to reflect on the main strategies investigated to overcome the barriers against effective systemic protein drug delivery in different routes of drug administration. Approaches based on chemical modifications and pharmaceutical technologies are discussed with reference to examples of drugs and devices that have shown potential, while attempts that have failed are also briefly outlined. PMID:25106909

  10. Nanocrystal technology, drug delivery and clinical applications

    PubMed Central

    Junghanns, Jens-Uwe A H; Müller, Rainer H

    2008-01-01

    Nanotechnology will affect our lives tremendously over the next decade in very different fields, including medicine and pharmacy. Transfer of materials into the nanodimension changes their physical properties which were used in pharmaceutics to develop a new innovative formulation principle for poorly soluble drugs: the drug nanocrystals. The drug nanocrystals do not belong to the future; the first products are already on the market. The industrially relevant production technologies, pearl milling and high pressure homogenization, are reviewed. The physics behind the drug nanocrystals and changes of their physical properties are discussed. The marketed products are presented and the special physical effects of nanocrystals explained which are utilized in each market product. Examples of products in the development pipelines (clinical phases) are presented and the benefits for in vivo administration of drug nanocrystals are summarized in an overview. PMID:18990939

  11. Conundrum and therapeutic potential of curcumin in drug delivery.

    PubMed

    Kumar, Anil; Ahuja, Alka; Ali, Javed; Baboota, Sanjula

    2010-01-01

    Turmeric, the source of the polyphenolic active compound curcumin (diferuloylmethane), has been used extensively in traditional medicine since ancient times as a household remedy against various diseases, including hepatic disorders, cough, sinusitis, rheumatism, and biliary disorders. In the past few decades, a number of studies have been done on curcumin showing its potential role in treating inflammatory disorders, cardiovascular disease, cancer, AIDS, and neurological disorders. However, the main drawback associated with curcumin is its poor aqueous solubility and stability in gastrointestinal fluids, which leads to poor bioavailability. Multifarious novel drug-delivery approaches, including microemulsions, nanoemulsions, liposomes, solid lipid nanoparticles, microspheres, solid dispersion, polymeric nanoparticles, and self-microemulsifying drug-delivery systems have been used to enhance the bioavailability and tissue-targeting ability of curcumin. These attempts have revealed promising results for enhanced bioavailability and targeting to disease such as cancer, but more extensive research on tissue-targeting and stability-related issues is needed. Tissue targeting and enhanced bioavailability of curcumin using novel drug-delivery methods with minimum side effects will