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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.

  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. 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

  4. 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

  5. Nanoengineered drug-releasing Ti wires as an alternative for local delivery of chemotherapeutics in the brain.

    PubMed

    Gulati, Karan; Aw, Moom Sinn; Losic, Dusan

    2012-01-01

    The blood-brain barrier (BBB) blocks the passage of active molecules from the blood which makes drug delivery to the brain a challenging problem. Oral drug delivery using chemically modified drugs to enhance their transport properties or remove the blocking of drug transport across the BBB is explored as a common approach to address these problems, but with limited success. Local delivery of drugs directly to the brain interstitium using implants such as polymeric wafers, gels, and catheters has been recognized as a promising alternative particularly for the treatment of brain cancer (glioma) and neurodegenerative disorders. The aim of this study was to introduce a new solution by engineering a drug-releasing implant for local drug delivery in the brain, based on titanium (Ti) wires with titania nanotube (TNT) arrays on their surfaces. Drug loading and drug release characteristics of this system were explored using two drugs commonly used in oral brain therapy: dopamine (DOPA), a neurotransmitter agent; and doxorubicin (DOXO), an anticancer drug. Results showed that TNT/Ti wires could provide a considerable amount of drugs (>170 μg to 1000 μg) with desirable release kinetics and controllable release time (1 to several weeks) and proved their feasibility for use as drug-releasing implants for local drug delivery in the brain. In this report, a new drug-releasing platform in the form of nanoengineered Ti wires with TNT arrays is proposed as an alternative for local delivery of chemotherapeutics in the brain to bypass the BBB. To prove this concept, drug loading and release characteristics of two drugs important for brain therapy (the neurotransmitter DOPA and the anticancer drug DOXO) were explored. Titania nanotube arrays on the surface of Ti wires (TNT/Ti) were fabricated using a simple anodization process, followed by separate loading of two drugs (DOPA and DOXO) inside the nanotube structures. The loading and in vitro release characteristics of prepared TNT

  6. 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.

  7. 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.

  8. Formulation development of smart gel periodontal drug delivery system for local delivery of chemotherapeutic agents with application of experimental design.

    PubMed

    Dabhi, Mahesh R; Nagori, Stavan A; Gohel, Mukesh C; Parikh, Rajesh K; Sheth, Navin R

    2010-01-01

    Smart gel periodontal drug delivery systems (SGPDDS) containing gellan gum (0.1-0.8% w/v), lutrol F127 (14, 16, and 18% w/v), and ornidazole (1% w/v) were designed for the treatment of periodontal diseases. Each formulation was characterized in terms of in vitro gelling capacity, viscosity, rheology, content uniformity, in vitro drug release, and syringeability. In vitro gelation time and the nature of the gel formed in simulated saliva for prepared formulations showed polymeric concentration dependency. Drug release data from all formulations was fitted to different kinetic models and the Korsemeyer-Peppas model was the best fit model. Drug release was significantly decreased as the concentration of each polymer component was increased. Increasing the concentration of each polymeric component significantly increased viscosity, syringeability, and time for 50%, 70%, and 90% drug release. In conclusion, the formulations described offer a wide range of physical and drug release characteristics. The formulation containing 0.8% w/v of gellan gum and 16% w/v of lutrol F127 exhibited superior physical characteristics.

  9. Targeted concurrent and sequential delivery of chemotherapeutic and antiangiogenic agents to the brain by using drug-loaded nanofibrous membranes

    PubMed Central

    Tseng, Yuan-Yun; Yang, Tao-Chieh; Wang, Yi-Chuan; Lee, Wei-Hwa; Chang, Tzu-Min; Kau, Yi-Chuan; Liu, Shih-Jung

    2017-01-01

    Glioblastoma is the most frequent and devastating primary brain tumor. Surgery followed by radiotherapy with concomitant and adjuvant chemotherapy is the standard of care for patients with glioblastoma. Chemotherapy is ineffective, because of the low therapeutic levels of pharmaceuticals in tumor tissues and the well-known tumor-cell resistance to chemotherapy. Therefore, we developed bilayered poly(d,l)-lactide-co-glycolide nanofibrous membranes that enabled the sequential and sustained release of chemotherapeutic and antiangiogenic agents by employing an electrospinning technique. The release characteristics of embedded drugs were determined by employing an in vitro elution technique and high-performance liquid chromatography. The experimental results showed that the fabricated nanofibers showed a sequential drug-eluting behavior, with the release of high drug levels of chemotherapeutic carmustine, irinotecan, and cisplatin from day 3, followed by the release of high concentrations of the antiangiogenic combretastatin from day 21. Biodegradable multidrug-eluting nanofibrous membranes were then dispersed into the cerebral cavity of rats by craniectomy, and the in vivo release characteristics of the pharmaceuticals from the membranes were investigated. The results suggested that the nanofibrous membranes released high concentrations of pharmaceuticals for more than 8 weeks in the cerebral parenchyma of rats. The result of histological analysis demonstrated developmental atrophy of brains with no inflammation. Biodegradable nanofibrous membranes can be manufactured for long-term sequential transport of different chemotherapeutic and anti-angiogenic agents in the brain, which can potentially improve the treatment of glioblastoma multiforme and prevent toxic effects due to systemic administration. PMID:28243088

  10. 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

  11. 131I-Traced PLGA-Lipid Nanoparticles as Drug Delivery Carriers for the Targeted Chemotherapeutic Treatment of Melanoma

    NASA Astrophysics Data System (ADS)

    Wang, Haiyan; Sheng, Weizhong

    2017-05-01

    Herein, folic acid (FA) conjugated Poly(d,l-lactide-co-glycolide) (PLGA)-lipid composites (FA-PL) were developed as nanocarriers for the targeted delivery of insoluble anti-cancer drug paclitaxel (PTX), resulting FA-PLP nanoparticles. Furthermore, 131I, as a radioactive tracer, was used to label FA-PLP nanoparticles (FA-PLP-131I) to evaluate their cell uptake activity, in vivo blood circulation, and biodistribution. The FA-PLP-131I nanoparticles had a spherical morphology with great stability, a narrow size distribution (165.6 and 181.2 nm), and -22.1 mV in average zeta potential. Confocal laser scanning microscopy indicated that the targeting molecule FA promotes PLP-131I uptake by melanoma B16F10 cells, which was further confirmed by the cell incorporation rate via 131I activity detection as measured by a gamma counter. FA-PLP-131I without PTX (FA-PL-131I) shows minor cytotoxicity, good biocompatibility, while FA-PLP-131I was demonstrated to have efficient cell viability suppression compared to free PTX and PLP-131I. Following intravenous injection, the blood circulation half-life of free PTX ( t 1/2 = 5.4 ± 0.23 h) was prolonged to 18.5 ± 0.5 h by FA-PLP-131I. Through FA targeting, the tumor uptake of FA-PLP-131I was approximately 4.41- and 12.8-fold higher compared to that of PLP-131I and free PTX-131I, respectively. Moreover, following 40 days of treatment, FA-PLP-131I showed an improved tumor inhibition effect compared to free PTX and PLP-131I, with no relapse and no remarkable systemic in vivo toxicity. The results demonstrate that the 131I-labeled PLGA-lipid nanoparticle can be simultaneously applied for targeted drug delivery and reliable tracking of drugs in vivo.

  12. Cisplatin@US-tube carbon nanocapsules for enhanced chemotherapeutic delivery.

    PubMed

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

    2012-02-01

    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 h. These studies have laid the foundation for developing US-tube-based delivery of chemotherapeutics, with drug release mainly limited to within cancer cells only. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Analysis of Chemotherapeutic Drug Delivery at the Single Cell Level Using 3D-MSI-TOF-SIMS.

    PubMed

    Vanbellingen, Quentin P; Castellanos, Anthony; Rodriguez-Silva, Monica; Paudel, Iru; Chambers, Jeremy W; Fernandez-Lima, Francisco A

    2016-12-01

    In this work, we show the advantages of label-free, tridimensional mass spectrometry imaging using dual beam analysis (25 keV Bi3(+)) and depth profiling (20 keV with a distribution centered at Ar1500(+)) coupled to time of flight secondary ion mass spectrometry (3D-MSI-TOF-SIMS) for the study of A-172 human glioblastoma cell line treated with B-cell lymphoma 2 (Bcl-2) inhibitor ABT-737. The high spatial (~250 nm) and high mass resolution (m/Δm ~10,000) of TOF-SIMS permitted the localization and identification of the intact, unlabeled drug molecular ion (m/z 811.26 C42H44ClN6O5S2(-) [M - H](-)) as well as characteristic fragment ions. We propose a novel approach based on the inspection of the drug secondary ion yield, which showed a good correlation with the drug concentration during cell treatment at therapeutic dosages (0-200 μM with 4 h incubation). Chemical maps using endogenous molecular markers showed that the ABT-737 is mainly localized in subsurface regions and absent in the nucleus. A semiquantitative workflow is proposed to account for the biological cell diversity based on the spatial distribution of endogenous molecular markers (e.g., nuclei and cytoplasm) and secondary ion confirmation based on the ratio of drug-specific fragments to molecular ion as a function of the therapeutic dosage. Graphical Abstract ᅟ.

  14. Analysis of Chemotherapeutic Drug Delivery at the Single Cell Level Using 3D-MSI-TOF-SIMS

    NASA Astrophysics Data System (ADS)

    Vanbellingen, Quentin P.; Castellanos, Anthony; Rodriguez-Silva, Monica; Paudel, Iru; Chambers, Jeremy W.; Fernandez-Lima, Francisco A.

    2016-12-01

    In this work, we show the advantages of label-free, tridimensional mass spectrometry imaging using dual beam analysis (25 keV Bi3 +) and depth profiling (20 keV with a distribution centered at Ar1500 +) coupled to time of flight secondary ion mass spectrometry (3D-MSI-TOF-SIMS) for the study of A-172 human glioblastoma cell line treated with B-cell lymphoma 2 (Bcl-2) inhibitor ABT-737. The high spatial ( 250 nm) and high mass resolution (m/Δm 10,000) of TOF-SIMS permitted the localization and identification of the intact, unlabeled drug molecular ion ( m/z 811.26 C42H44ClN6O5S2 - [M - H]-) as well as characteristic fragment ions. We propose a novel approach based on the inspection of the drug secondary ion yield, which showed a good correlation with the drug concentration during cell treatment at therapeutic dosages (0-200 μM with 4 h incubation). Chemical maps using endogenous molecular markers showed that the ABT-737 is mainly localized in subsurface regions and absent in the nucleus. A semiquantitative workflow is proposed to account for the biological cell diversity based on the spatial distribution of endogenous molecular markers (e.g., nuclei and cytoplasm) and secondary ion confirmation based on the ratio of drug-specific fragments to molecular ion as a function of the therapeutic dosage.

  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. 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

  17. 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.

  18. Heat Shock Protein translocation induced by membrane fluidization increases tumor-cell sensitivity to chemotherapeutic drugs.

    PubMed

    Dempsey, Nina C; Ireland, H Elyse; Smith, Carly M; Hoyle, Christine F; Williams, John H H

    2010-10-28

    Treatment of chronic lymphocytic leukemia (CLL) remains a challenge due to the frequency of drug resistance amongst patients. Improving the delivery of chemotherapeutic agents while reducing the expression of anti-apoptotic Heat Shock Proteins (HSPs) within the cancer cells may facilitate in overcoming this drug resistance. We demonstrate for the first time that sub-lethal doses of chemotherapeutic agents can be combined with membrane fluidizing treatments to produce a significant increase in drug efficacy and apoptosis in vitro. We show that fluidizers result in a transient decrease in intracellular HSPs, resulting in increased tumor-cell sensitivity and a membrane-associated induction of HSP gene expression.

  19. Intelligent hydrogels for the oral delivery of chemotherapeutics.

    PubMed

    Bromberg, Lev

    2005-11-01

    A novel approach toward improvements of oral chemotherapeutic formulations has evolved, which combines solubilisation (molecular dispersion) of the hydrophobic anticancer drugs in micelles attached to large macromolecules or microparticles. The large size of the macromolecules or microgels prevents the gel components from being transported into the systemic circulation. The discussed gels comprise copolymers of poly(acrylic acid) (PAA) and Pluronic surfactants, linked via C-C bonds. The Pluronic-PAA copolymers are non-irritating when administered orally. The micelles formed in the Pluronic-PAA solutions and in crosslinked microgels can be loaded with chemotherapeutic drugs and then released in contact with the intestine. The microgels are collapsed at the acidic pH of the stomach and expand, thus releasing the loaded drugs at the pH of the lower gastrointestinal tract. Yet the microgels are mucoadhesive and enable longer retention time and prolonged release in the colon. Ease of preparation and formulation of the drugs with the Pluronic-PAA polymers and gels may enable the wider use of oral chemotherapy, resulting in a better patient compliance and improved quality of life of the patients.

  20. Liposomal chemotherapeutics.

    PubMed

    Gentile, Emanuela; Cilurzo, Felisa; Di Marzio, Luisa; Carafa, Maria; Ventura, Cinzia Anna; Wolfram, Joy; Paolino, Donatella; Celia, Christian

    2013-12-01

    Currently, six liposomal chemotherapeutics have received clinical approval and many more are in clinical trials or undergoing preclinical evaluation. Liposomes exhibit low toxicity and improve the biopharmaceutical features and therapeutic index of drugs, thereby increasing efficacy and reducing side effects. In this review we discuss the advantages of using liposomes for the delivery of chemotherapeutics. Gemcitabine and paclitaxel have been chosen as examples to illustrate how the performance of a metabolically unstable or poorly water-soluble drug can be greatly improved by liposomal incorporation. We look at the beneficial effects of liposomes in a variety of solid and blood-borne tumors, including thyroid cancer, pancreatic cancer, breast cancer and multiple myeloma.

  1. 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

  2. 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

  3. 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

  4. PHB-Based Gels as Delivery Agents of Chemotherapeutics for the Effective Shrinkage of Tumors.

    PubMed

    Wu, Yun-Long; Wang, Han; Qiu, Ying-Kun; Liow, Sing Shy; Li, Zibiao; Loh, Xian Jun

    2016-10-01

    Injectable thermogel to deliver chemotherapeutics in a minimally invasive manner and to achieve their long term sustained release at tumor sites to minimize side effects is attractive for chemotherapy and precision medicine, but its rational design remains a challenge. In this work, a copolymer with natural biodegradable poly[(R)-3-hydroxybutyrate] (PHB), hydrophilic poly(ethylene glycol), and temperature sensitive poly(propylene glycol) blocks linked by urethane linkages is designed to show thermogelling characteristics which are beneficial for minimally invasive injection and safe degradation. This thermogelling polymer possesses in vitro biocompatibility with very low cyto-toxicity in HEK293 cells. Furthermore, it is able to form the gel to achieve the controllable release of paclitaxel (PTX) and doxorubicin (DOX) by adjusting polymer concentrations. A rodent model of hepatocarcinoma has been performed to demonstrate the in vivo applications of this PHB-based thermogel. The drug-loaded thermogel has been intratumorally injected and both PTX-loaded and DOX-loaded thermogel have significantly slowed down tumor growth. This work represents the first time that injectable PHB thermogels have possessed good controllable release effect of chemotherapeutics against the in vivo model of tumors and will benefit various applications, including on-demand drug delivery and personalized medicine.

  5. Recent advances in biocompatible nanocarriers for delivery of chemotherapeutic cargoes towards cancer therapy.

    PubMed

    Ang, Chung Yen; Tan, Si Yu; Zhao, Yanli

    2014-07-21

    Cancer is currently one of the major diseases that has gained a lot of scientific attention. Conventional cancer therapeutics involve surgical removal of tumors from patients followed by chemotherapeutic treatment. In the use of anticancer drugs during the chemotherapy process, patients often suffer from a variety of undesirable side effects including damage to normal organs. Thus, there is an urgent need for the development of novel strategies to overcome these side effect issues. Among several strategies, the utilization of nanocarriers for anticancer drug delivery has shown improved therapeutic efficiency of the drugs with minimization of the undesirable side effects. In this review, we discuss various types of nanocarriers recently reported in the literature for application in cancer therapy. We introduce some targeting ligands that have been functionalized on nanocarriers in order to impart specificity to the nanocarriers for targeted drug delivery. We also highlight some therapeutic cargoes that are commonly used and their therapeutic mechanisms in cancer treatment. Finally, we summarize some interesting stimulus strategies for controlled release of therapeutic cargoes at tumor sites. This review is expected to inspire new ideas and create novel strategies in advancing efficient cancer therapy using nanomedicine approaches.

  6. Combination of metformin with chemotherapeutic drugs via different molecular mechanisms.

    PubMed

    Peng, Mei; Darko, Kwame Oteng; Tao, Ting; Huang, Yanjun; Su, Qiongli; He, Caimei; Yin, Tao; Liu, Zhaoqian; Yang, Xiaoping

    2017-03-01

    Metformin, a widely prescribed drug for treating type II diabetes, is one of the most extensively recognized metabolic modulators which has shown an important anti-cancer property. However, fairly amount of clinical trials on its single administration have not demonstrated a convincing efficiency yet. Thus, recent studies tend to combine metformin with clinical commonly used chemotherapeutic drugs to decrease their toxicity and attenuate their tumor resistance. These strategies have displayed promising clinical benefits. Interestingly, metformin experiences a diversity of molecular mechanisms when it combines different chemotherapeutic drugs. For example, AMPK/mTOR signaling pathway activation plays a major role when it combines with hormone modulating drugs. In contrast, suppression of HIF-1, p-gp and MRP1 protein expression is its main mechanism when metformin combines with anti-metabolites. Furthermore, when combining of metformin with antibiotics, inhibition of oxidative stress and inflammatory signaling pathway becomes a novel pharmaceutical mechanism for its cardio-protective effect. Induction of apoptotic mitochondria and nucleus could be the major player for the synergistic effect of its combination with cisplatin. In contrast, down-regulation of lipoprotein or cholesterol synthesis might be the undefined molecular base when metformin combines with taxane. Thus, deep exploration of molecular mechanisms of metformin with these different drugs is critical to understand its synergistic effect and help for personalized administration. In this mini-review, detailed molecular mechanisms of these combinations are discussed and summarized. This work will promote better understanding of molecular mechanisms of metformin and provide precise targets to identify specific patient groups to achieve satisfactory treatment efficacy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. 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

  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. Plasma and cerebrospinal fluid pharmacokinetics of select chemotherapeutic agents following intranasal delivery in a non-human primate model.

    PubMed

    League-Pascual, James C; Lester-McCully, Cynthia M; Shandilya, Shaefali; Ronner, Lukas; Rodgers, Louis; Cruz, Rafael; Peer, Cody J; Figg, William D; Warren, Katherine E

    2017-03-13

    The blood-brain barrier (BBB) limits entry of most chemotherapeutic agents into the CNS, resulting in inadequate exposure within CNS tumor tissue. Intranasal administration is a proposed means of delivery that can bypass the BBB, potentially resulting in more effective chemotherapeutic exposure at the tumor site. The objective of this study was to evaluate the feasibility and pharmacokinetics (plasma and CSF) of intranasal delivery using select chemotherapeutic agents in a non-human primate (NHP) model. Three chemotherapeutic agents with known differences in CNS penetration were selected for intranasal administration in a NHP model to determine proof of principle of CNS delivery, assess tolerability and feasibility, and to evaluate whether certain drug characteristics were associated with increased CNS exposure. Intravenous (IV) temozolomide (TMZ), oral (PO) valproic acid, and PO perifosine were administered to adult male rhesus macaques. The animals received a single dose of each agent systemically and intranasally in separate experiments, with each animal acting as his own control. The dose of the agents administered systemically was the human equivalent of a clinically appropriate dose, while the intranasal dose was the maximum achievable dose based on the volume limitation of 1 mL. Multiple serial paired plasma and CSF samples were collected and quantified using a validated uHPLC/tandem mass spectrometry assay after each drug administration. Pharmacokinetic parameters were estimated using non-compartmental analysis. CSF penetration was calculated from the ratio of areas under the concentration-time curves for CSF and plasma (AUCCSF:plasma). Intranasal administration was feasible and tolerable for all agents with no significant toxicities observed. For TMZ, the degrees of CSF drug penetration after intranasal and IV administration were 36 (32-57) and 22 (20-41)%, respectively. Although maximum TMZ drug concentration in the CSF (Cmax) was lower after intranasal

  10. Oncolytic herpes viruses, chemotherapeutics, and other cancer drugs

    PubMed Central

    Braidwood, Lynne; Graham, Sheila V; Graham, Alex; Conner, Joe

    2013-01-01

    Oncolytic viruses are emerging as a potential new way of treating cancers. They are selectively replication-competent viruses that propagate only in actively dividing tumor cells but not in normal cells and, as a result, destroy the tumor cells by consequence of lytic infection. At least six different oncolytic herpes simplex viruses (oHSVs) have undergone clinical trials worldwide to date, and they have demonstrated an excellent safety profile and intimations of efficacy. The first pivotal Phase III trial with an oHSV, talimogene laherparepvec (T-Vec [OncoVexGM-CSF]), is almost complete, with extremely positive early results reported. Intuitively, therapeutically beneficial interactions between oHSV and chemotherapeutic and targeted therapeutic drugs would be limited as the virus requires actively dividing cells for maximum replication efficiency and most anticancer agents are cytotoxic or cytostatic. However, combinations of such agents display a range of responses, with antagonistic, additive, or, perhaps most surprisingly, synergistic enhancement of antitumor activity. When synergistic interactions in cancer cell killing are observed, chemotherapy dose reductions that achieve the same overall efficacy may be possible, resulting in a valuable reduction of adverse side effects. Therefore, the combination of an oHSV with “standard-of-care” drugs makes a logical and reasonable approach to improved therapy, and the addition of a targeted oncolytic therapy with “standard-of-care” drugs merits further investigation, both preclinically and in the clinic. Numerous publications report such studies of oncolytic HSV in combination with other drugs, and we review their findings here. Viral interactions with cellular hosts are complex and frequently involve intracellular signaling networks, thus creating diverse opportunities for synergistic or additive combinations with many anticancer drugs. We discuss potential mechanisms that may lead to synergistic interactions

  11. 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.

  12. 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

  13. 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

  14. Buccal drug delivery.

    PubMed

    Smart, John D

    2005-05-01

    Buccal formulations have been developed to allow prolonged localised therapy and enhanced systemic delivery. The buccal mucosa, however, while avoiding first-pass effects, is a formidable barrier to drug absorption, especially for biopharmaceutical products (proteins and oligonucleotides) arising from the recent advances in genomics and proteomics. The buccal route is typically used for extended drug delivery, so formulations that can be attached to the buccal mucosa are favoured. The bioadhesive polymers used in buccal drug delivery to retain a formulation are typically hydrophilic macro-molecules containing numerous hydrogen bonding groups. Newer second-generation bioadhesives have been developed and these include modified or new polymers that allow enhanced adhesion and/or drug delivery, in addition to site-specific ligands such as lectins. Over the last 20 years a wide range of formulations has been developed for buccal drug delivery (tablet, patch, liquids and semisolids) but comparatively few have found their way onto the market. Currently, this route is restricted to the delivery of a limited number of small lipophilic molecules that readily cross the buccal mucosa. However, this route could become a significant means for the delivery of a range of active agents in the coming years, if the barriers to buccal drug delivery are overcome. In particular, patient acceptability and the successful systemic delivery of large molecules (proteins, oligonucleotides and polysaccharides) via this route remains both a significant opportunity and challenge, and new/improved technologies may be required to address these.

  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. Nuclear drug delivery for cancer chemotherapy.

    PubMed

    Sui, Meihua; Liu, Wenwen; Shen, Youqing

    2011-10-30

    Nanosystems with unique physical and biological properties have been extensively explored for cancer targeted intracellular delivery of small-molecular chemotherapeutic drugs to increase their therapeutic efficacies and to minimize their side effects. A large number of anticancer drugs are DNA-toxins that bind nuclear DNA or its associated enzymes to exert their cytotoxicity to cancer cells. After entering tumor cells, they need to be further delivered to the nucleus for actions. Herein, we discuss the biological barriers and summarize recent progress of nuclear drug delivery for cancer chemotherapy, emphasizing strategies that appear useful for design of vehicles capable of delivering drugs to the nucleus, particularly for in vivo applications. The existing obstacles or problems that need to be overcome before successful applications of nuclear drug delivery for cancer chemotherapy are also discussed.

  18. Biomarker-Guided Repurposing of Chemotherapeutic Drugs for Cancer Therapy: A Novel Strategy in Drug Development

    PubMed Central

    Stenvang, Jan; Kümler, Iben; Nygård, Sune Boris; Smith, David Hersi; Nielsen, Dorte; Brünner, Nils; Moreira, José M. A.

    2013-01-01

    Cancer is a leading cause of mortality worldwide and matters are only set to worsen as its incidence continues to rise. Traditional approaches to combat cancer include improved prevention, early diagnosis, optimized surgery, development of novel drugs, and honing regimens of existing anti-cancer drugs. Although discovery and development of novel and effective anti-cancer drugs is a major research area, it is well known that oncology drug development is a lengthy process, extremely costly and with high attrition rates. Furthermore, those drugs that do make it through the drug development mill are often quite expensive, laden with severe side-effects and unfortunately, to date, have only demonstrated minimal increases in overall survival. Therefore, a strong interest has emerged to identify approved non-cancer drugs that possess anti-cancer activity, thus shortcutting the development process. This research strategy is commonly known as drug repurposing or drug repositioning and provides a faster path to the clinics. We have developed and implemented a modification of the standard drug repurposing strategy that we review here; rather than investigating target-promiscuous non-cancer drugs for possible anti-cancer activity, we focus on the discovery of novel cancer indications for already approved chemotherapeutic anti-cancer drugs. Clinical implementation of this strategy is normally commenced at clinical phase II trials and includes pre-treated patients. As the response rates to any non-standard chemotherapeutic drug will be relatively low in such a patient cohort it is a pre-requisite that such testing is based on predictive biomarkers. This review describes our strategy of biomarker-guided repurposing of chemotherapeutic drugs for cancer therapy, taking the repurposing of topoisomerase I (Top1) inhibitors and Top1 as a potential predictive biomarker as case in point. PMID:24400218

  19. Application of elastin-mimetic recombinant proteins in chemotherapeutics delivery, cellular engineering, and regenerative medicine.

    PubMed

    Jeon, Won Bae

    2013-01-01

    With the remarkable increase in the fields of biomedical engineering and regenerative medicine, biomaterial design has become an indispensable approach for developing the biocompatible carriers for drug or gene cargo and extracellular matrix (ECM) for cell survival, proliferation and differentiation. Native ECM materials derived from animal tissues were believed to be the best choices for tissue engineering. However, possible pathogen contamination by cellular remnants from foreign animal tissues is an unavoidable issue that has limited the use of native ECM for human benefit. Some synthetic polymers have been used as alternative materials for manufacturing native ECM because of the biodegradability and ease of large-scale production of the polymers. However, the inherent polydispersity of the polymers causes batch-to-batch variation in polymer composition and possible cytotoxic interactions between chemical matrices and neighboring cells or tissues have not yet been fully resolved. Elastin-like proteins (ELPs) are genetically engineered biopolymers modeled after the naturally occurring tropoelastin and have emerged as promising materials for biomedical applications because they are biocompatible, non-immunogenic and biodegradable, and their composition, mechanical stiffness and even fate within the cell can be controlled at the gene level. This commentary highlights the recent progresses in the development of the ELP-based recombinant proteins that are being increasingly used for the delivery of chemotherapeutics and to provide a cell-friendly ECM environment.

  20. Application of elastin-mimetic recombinant proteins in chemotherapeutics delivery, cellular engineering, and regenerative medicine

    PubMed Central

    Jeon, Won Bae

    2013-01-01

    With the remarkable increase in the fields of biomedical engineering and regenerative medicine, biomaterial design has become an indispensable approach for developing the biocompatible carriers for drug or gene cargo and extracellular matrix (ECM) for cell survival, proliferation and differentiation. Native ECM materials derived from animal tissues were believed to be the best choices for tissue engineering. However, possible pathogen contamination by cellular remnants from foreign animal tissues is an unavoidable issue that has limited the use of native ECM for human benefit. Some synthetic polymers have been used as alternative materials for manufacturing native ECM because of the biodegradability and ease of large-scale production of the polymers. However, the inherent polydispersity of the polymers causes batch-to-batch variation in polymer composition and possible cytotoxic interactions between chemical matrices and neighboring cells or tissues have not yet been fully resolved. Elastin-like proteins (ELPs) are genetically engineered biopolymers modeled after the naturally occurring tropoelastin and have emerged as promising materials for biomedical applications because they are biocompatible, non-immunogenic and biodegradable, and their composition, mechanical stiffness and even fate within the cell can be controlled at the gene level. This commentary highlights the recent progresses in the development of the ELP-based recombinant proteins that are being increasingly used for the delivery of chemotherapeutics and to provide a cell-friendly ECM environment. PMID:23475122

  1. Ultrasonic drug delivery--a general review.

    PubMed

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

    2004-11-01

    Ultrasound has an ever-increasing role in the delivery of therapeutic agents, including genetic material, protein 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 permeabilise cell membranes and disrupt the vesicles that carry drugs. Thus, the presence of microbubbles enormously enhances ultrasonic delivery of genetic material, proteins and smaller chemical agents. Numerous reports show that the most efficient delivery of genetic material occurs in the presence of cavitating microbubbles. Attaching the DNA directly to the microbubbles, or to gas-containing liposomes, enhances gene uptake even further. Ultrasonic-enhanced gene delivery has been studied in various tissues, including cardiac, vascular, skeletal muscle, tumour and even fetal tissue. Ultrasonic-assisted delivery of proteins has found most application in transdermal transport 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; and makes 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 on cells and drug-carrying vesicles.

  2. Sublingual drug delivery.

    PubMed

    Goswami, Tarun; Jasti, Bhaskara; Li, Xiaoling

    2008-01-01

    The sublingual route is one of the early modes of administration for systemic drug delivery. This route avoids first-pass metabolism and affords quick drug entry into the systemic circulation. Attempts have been made to deliver various pharmacologically active agents, such as cardiovascular drugs, analgesics, and peptides, across the sublingual mucosa. In this review, the anatomical structure, blood supply, biochemical composition, transport pathways, permeation enhancement strategies, in vitro/in vivo models, and clinical investigations for the sublingual route of drug delivery is discussed.

  3. Drug delivery approaches for breast cancer.

    PubMed

    Singh, Santosh Kumar; Singh, Shriti; Lillard, James W; Singh, Rajesh

    2017-01-01

    Breast cancer is one of the most common cancers affecting women worldwide. The controlled release of drugs to the precise site of the disease using a nanocarrier vehicle increases the therapeutic efficiency of the drugs. Nanotechnology-based approaches used to endorse clinical improvement from a disease also help to understand the interaction of malignant cells with their microenvironment. Receptor-based targeting is another approach for drug delivery which is undergoing clinical trials. Nanoparticles (NPs) delivery has been proven to promise high loading capacity, less toxicity, and stability of the drugs or biomolecules compared to traditional chemotherapeutic drugs. The goal of this review is to present the current problems of breast cancer therapy and discuss the NP-based targeting to overcome the hurdles of conventional drug therapy approach.

  4. From The Mine to Cancer Therapy: Natural and Biodegradable Theranostic Silicon Nanocarriers from Diatoms for Sustained Delivery of Chemotherapeutics.

    PubMed

    Maher, Shaheer; Kumeria, Tushar; Wang, Ye; Kaur, Gagandeep; Fathalla, Dina; Fetih, Gihan; Santos, Abel; Habib, Fawzia; Evdokiou, Andreas; Losic, Dusan

    2016-10-01

    Drug delivery using synthetic nanoparticles including porous silicon has been extensively used to overcome the limitations of chemotherapy. However, their synthesis has many challenges such as lack of scalability, high cost, and the use of toxic materials with concerning environmental impact. Nanoscale materials obtained from natural resources are an attractive option to address some of these disadvantages. In this paper, a new mesoporous biodegradable silicon nanoparticle (SiNP) drug carrier obtained from natural diatom silica mineral available from the mining industry is presented. Diatom silica structures are mechanically fragmented and converted into SiNPs by simple and scalable magnesiothermic reduction process. Results show that SiNPs have many desirable properties including high surface area, high drug loading capacity, strong luminescence, biodegradability, and no cytotoxicity. The in-vitro release results from SiNPs loaded with anticancer drugs (doxorubicin) demonstrate a pH-dependent and sustained drug release with enhanced cytotoxicity against cancer cells. The cells study using doxorubicin loaded SiNPs shows a significantly enhanced cytotoxicity against cancer cells compared with free drug, suggesting their considerable potential as theranostic nanocarriers for chemotherapy. Their low-cost manufacturing using abundant natural materials and outstanding chemotherapeutic performance has made them as a promising alternative to synthetic nanoparticles for drug delivery applications.

  5. Microfabrication for Drug Delivery

    PubMed Central

    Koch, Brendan; Rubino, Ilaria; Quan, Fu-Shi; Yoo, Bongyoung; Choi, Hyo-Jick

    2016-01-01

    This review is devoted to discussing the application of microfabrication technologies to target challenges encountered in life processes by the development of drug delivery systems. Recently, microfabrication has been largely applied to solve health and pharmaceutical science issues. In particular, fabrication methods along with compatible materials have been successfully designed to produce multifunctional, highly effective drug delivery systems. Microfabrication offers unique tools that can tackle problems in this field, such as ease of mass production with high quality control and low cost, complexity of architecture design and a broad range of materials. Presented is an overview of silicon- and polymer-based fabrication methods that are key in the production of microfabricated drug delivery systems. Moreover, the efforts focused on studying the biocompatibility of materials used in microfabrication are analyzed. Finally, this review discusses representative ways microfabrication has been employed to develop systems delivering drugs through the transdermal and oral route, and to improve drug eluting implants. Additionally, microfabricated vaccine delivery systems are presented due to the great impact they can have in obtaining a cold chain-free vaccine, with long-term stability. Microfabrication will continue to offer new, alternative solutions for the development of smart, advanced drug delivery systems. PMID:28773770

  6. 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.

  7. 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

  8. 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

  9. 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.

  10. New in vitro system to predict chemotherapeutic efficacy of drug combinations in fresh tumor samples

    PubMed Central

    Weidemüller, Paula; Krapfl, Jens; Yassin-Kelepir, Rauaa; Job, Laura; Fraefel, Marius; Braicu, Ioana; Kopp-Schneider, Annette; Sehouli, Jalid; De Wilde, Rudy Leon

    2017-01-01

    Background To find the best individual chemotherapy for cancer patients, the efficacy of different chemotherapeutic drugs can be predicted by pretesting tumor samples in vitro via the chemotherapy-resistance (CTR)-Test®. Although drug combinations are widely used among cancer therapy, so far only single drugs are tested by this and other tests. However, several first line chemotherapies are combining two or more chemotherapeutics, leading to the necessity of drug combination testing methods. Methods We established a system to measure and predict the efficacy of chemotherapeutic drug combinations with the help of the Loewe additivity concept in combination with the CTR-test. A combination is measured by using half of the monotherapy’s concentration of both drugs simultaneously. With this method, the efficacy of a combination can also be calculated based on single drug measurements. Results The established system was tested on a data set of ovarian carcinoma samples using the combination carboplatin and paclitaxel and confirmed by using other tumor species and chemotherapeutics. Comparing the measured and the calculated values of the combination testings revealed a high correlation. Additionally, in 70% of the cases the measured and the calculated values lead to the same chemotherapeutic resistance category of the tumor. Conclusion Our data suggest that the best drug combination consists of the most efficient single drugs and the worst drug combination of the least efficient single drugs. Our results showed that single measurements are sufficient to predict combinations in specific cases but there are exceptions in which it is necessary to measure combinations, which is possible with the presented system. PMID:28265509

  11. 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.

  12. 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

  13. 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.

  14. Strategy for chemotherapeutic delivery using a nanosized porous metal-organic framework with a central composite design

    PubMed Central

    Li, Yingpeng; Li, Xiuyan; Guan, Qingxia; Zhang, Chunjing; Xu, Ting; Dong, Yujing; Bai, Xinyu; Zhang, Weiping

    2017-01-01

    Background Enhancing drug delivery is an ongoing endeavor in pharmaceutics, especially when the efficacy of chemotherapy for cancer is concerned. In this study, we prepared and evaluated nanosized HKUST-1 (nanoHKUST-1), nanosized metal-organic drug delivery framework, loaded with 5-fluorouracil (5-FU) for potential use in cancer treatment. Materials and methods NanoHKUST-1 was prepared by reacting copper (II) acetate [Cu(OAc)2] and benzene-1,3,5-tricarboxylic acid (H3BTC) with benzoic acid (C6H5COOH) at room temperature (23.7°C±2.4°C). A central composite design was used to optimize 5-FU-loaded nanoHKUST-1. Contact time, ethanol concentration, and 5-FU:material ratios were the independent variables, and the entrapment efficiency of 5-FU was the response parameter measured. Powder X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nitrogen adsorption were used to determine the morphology of nanoHKUST-1. In addition, 5-FU release studies were conducted, and the in vitro cytotoxicity was evaluated. Results Entrapment efficiency and drug loading were 9.96% and 40.22%, respectively, while the small-angle X-ray diffraction patterns confirmed a regular porous structure. The SEM and TEM images of the nanoHKUST-1 confirmed the presence of round particles (diameter: approximately 100 nm) and regular polygon arrays of mesoporous channels of approximately 2–5 nm. The half-maximal lethal concentration (LC50) of the 5-FU-loaded nanoHKUST-1 was approximately 10 µg/mL. Conclusion The results indicated that nanoHKUST-1 is a potential vector worth developing as a cancer chemotherapeutic drug delivery system. PMID:28260892

  15. Nanomaterials for Drugs Delivery

    SciTech Connect

    Márquez, Francisco; Morant, Carmen

    2014-07-01

    Nanotechnology has revolutionized engineering, biology, chemistry, physics and medicine of today. These disciplines are evolving thanks to the ongoing development of new materials and applications. Nanomedicine, as application of nanotechnology in the field of health care, has undergone unprecedented development. Some of these changes have real applications as, for example, the use of nanoparticles in MRI imaging, in hyperthermia, in immunotherapy, or to improve the bioavailability of drugs, among others. Furthermore, when a drug is administered to a patient, the blood distributes it throughout the body. In the case of very localized diseases (i.e. tumors), only a small fraction of the drug reaches the target. Chemotherapy is one of the most aggressive treatment options used in some types of cancer, and is usually administered intravenously. The drug circulates throughout the body, reaching and destroying healthy and cancerous tissues, producing side effects throughout the body, sometimes with serious consequences for the health of the patient (nephrotoxicity, cardiotoxicity, peripheral neuropathy, anemia, etc.) in this type of therapy. Among the many applications of nanotechnology, the fabrication of nanostructures capable of safely transporting these drugs is seen as a strategy for reducing these side effects. Nanoparticles are able to carry and release the drug in the right place and with the required dose, greatly reducing the problems associated with direct treatment with these drugs. In recent years, there have been continuous improvements in the design and development of new tailor-made drug delivery systems, including hollow magnetic nanoparticles, liposomal structures, dendrimers, nanoporous silicon, etc. These structures can be obtained with different molecular weights (in the case of polymers), structures, shapes, and even with the appropriate functional groups for interaction at the desired positions. But, a great effort is still required to solve many

  16. Nanomaterials for Drugs Delivery

    DOE PAGES

    Márquez, Francisco; Morant, Carmen

    2014-07-01

    Nanotechnology has revolutionized engineering, biology, chemistry, physics and medicine of today. These disciplines are evolving thanks to the ongoing development of new materials and applications. Nanomedicine, as application of nanotechnology in the field of health care, has undergone unprecedented development. Some of these changes have real applications as, for example, the use of nanoparticles in MRI imaging, in hyperthermia, in immunotherapy, or to improve the bioavailability of drugs, among others. Furthermore, when a drug is administered to a patient, the blood distributes it throughout the body. In the case of very localized diseases (i.e. tumors), only a small fraction ofmore » the drug reaches the target. Chemotherapy is one of the most aggressive treatment options used in some types of cancer, and is usually administered intravenously. The drug circulates throughout the body, reaching and destroying healthy and cancerous tissues, producing side effects throughout the body, sometimes with serious consequences for the health of the patient (nephrotoxicity, cardiotoxicity, peripheral neuropathy, anemia, etc.) in this type of therapy. Among the many applications of nanotechnology, the fabrication of nanostructures capable of safely transporting these drugs is seen as a strategy for reducing these side effects. Nanoparticles are able to carry and release the drug in the right place and with the required dose, greatly reducing the problems associated with direct treatment with these drugs. In recent years, there have been continuous improvements in the design and development of new tailor-made drug delivery systems, including hollow magnetic nanoparticles, liposomal structures, dendrimers, nanoporous silicon, etc. These structures can be obtained with different molecular weights (in the case of polymers), structures, shapes, and even with the appropriate functional groups for interaction at the desired positions. But, a great effort is still required to

  17. Multifaceted Applications of Chitosan in Cancer Drug Delivery and Therapy.

    PubMed

    Babu, Anish; Ramesh, Rajagopal

    2017-03-27

    Chitosan is a versatile polysaccharide of biological origin. Due to the biocompatible and biodegradable nature of chitosan, it is intensively utilized in biomedical applications in scaffold engineering as an absorption enhancer, and for bioactive and controlled drug release. In cancer therapy, chitosan has multifaceted applications, such as assisting in gene delivery and chemotherapeutic delivery, and as an immunoadjuvant for vaccines. The present review highlights the recent applications of chitosan and chitosan derivatives in cancer therapy.

  18. 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. © 2015 Elsevier Inc. All rights reserved.

  19. Macrophages as drug delivery vehicles for photochemical internalization (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Madsen, Steen J.; Gonzalez, Jonathan; Molina, Stephanie; Kumar Nair, Rohit; Hirschberg, Henry

    2017-02-01

    Targeted delivery of chemotherapeutic drugs to tumor sites is a major challenge in cancer chemotherapy. Cell-based vectorization of therapeutic agents has great potential for cancer therapy in that it can target and maintain an elevated concentration of therapeutic agents at the tumor site and prevent their spread into healthy tissue. The use of circulating cells such as monocytes/macrophages (Ma) offers several advantages compared to nanoparticles as targeted drug delivery vehicles. Ma can be easily obtained from the patient, loaded in vitro with drugs and reinjected into the blood stream. Ma can selectively cross the partially compromised blood-brain barrier surrounding brain tumors and are known to actively migrate to tumors, drawn by chemotactic factors, including hypoxic regions where conventional chemo and radiation therapy are least effective. The utility of Ma as targeted drug delivery vehicles for photochemical internalization (PCI) of tumors was investigated in this study. In vitro studies were conducted using a mixture of F98 rat glioma cells and rat macrophages loaded with a variety of chemotherapeutic agents including bleomycin and 5-fluorouracil. Preliminary data show that macrophages are resistant to both chemotherapeutics while significant toxicity is observed for F98 cells exposed to both drugs. Co-incubation of F98 cells with loaded Ma results in significant F98 toxicity suggesting that Ma are releasing the drugs and, hence providing the rationale for their use as delivery vectors for cancer therapies such as PCI.

  20. 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

  1. Chemotherapeutic drugs and human tumor cells cytokine network

    PubMed Central

    Levina, Vera; Su, Yunyun; Nolen, Brian; Liu, Xiaoning; Gordin, Yuri; Lee, Melissa; Lokshin, Anna; Gorelik, Elieser

    2008-01-01

    The ability of human tumor cell lines to produce various cytokines, chemokines, angiogenic and growth factors was investigated using Luminex multiplex technology. Media conditioned by tumor cells protected tumor cells from drug-induced apoptosis and stimulated tumor cell proliferation. Antibodies neutralizing IL-6, CXCL8, CCL2 and CCL5 blocked this stimulation. Treatment of tumor cells with doxorubicin and cisplatin resulted in a substantial increase in the production of IL-6, CXCL8, CCL2, CCL5, BFGF, G-CSF, and VEGF. This stimulation was associated with drug-induced activation of NF-κB, AP-1, AP-2, CREB, HIF-1, STAT-1, STAT-3, STAT-5 and ATF-2 transcription factors and up-regulation of IL-6, CXCL8, FGF-2, CSF-3 and CCL5 gene expression. Treatment of tumor cells with doxorubicin and antibodies neutralizing G-CSF, CCL2 or CCL5 had higher inhibitory effects than each modality used alone. These results indicate that chemokines and growth factors produced by tumor by binding to the cognate receptors on tumor and stroma cells could provide proliferative and anti-apoptotic signals helping tumor to escape drug-mediated destruction. Clinical studies showed that antibodies neutralizing VEGF (Avastin/ Bevacizumab) or blocking HER2/neu signaling (Herceptin/ Trastuzumab) could increase the efficacy of chemotherapy although these beneficial effects have been limited. It is possible that drug-stimulated production of growth and pro-angiogenic factors could counterbalance the effects of antibody therapy. In addition, numerous growth factors and chemokines share angiogenic and growth-stimulating properties, and thus reduction of a single factor is insufficient to completely block tumor growth. Thus, a broad disruption of tumor cytokine network is needed to further increase the efficacy of cancer therapy. PMID:18697197

  2. Towards magnetic-enhanced cellular uptake, MRI and chemotherapeutics delivery by magnetic mesoporous silica nanoparticles.

    PubMed

    Liu, Qian; Zhang, Jixi; Xia, Weiliang; Gu, Hongchen

    2012-10-01

    A type of nanoparticle with three functional modalities was prepared with the aim of providing a multifunctional drug delivery system. The nanoparticle was 50 nm in size, with 2.7 nm mesopores and a magnetic nanocrystal core, which was further doped with FITC to enable the tracking of cellular uptake. We demonstrated that the internalization of the nanoparticles in tumor cells could be enhanced by applying an external magnetic field and furthermore, this kind of nanoparticle could be used in magnetic targeted drug delivery. With high transverse relaxivity, the magnetic nanoparticles shortened proton relaxation time and induced high magnetic resonance imaging contrast in tumor cells. Studies on anticancer drug loading and delivery capacity of anticancer drugs also showed that this type of nanoparticles could load water-soluble doxorubicin, and produce a prominent inhibitive effect against tumor cells. Taken together, the presented nanoparticles could become a promising agent in cancer theranostics.

  3. Prodrug-based nanoparticulate drug delivery strategies for cancer therapy.

    PubMed

    Luo, Cong; Sun, Jin; Sun, Bingjun; He, Zhonggui

    2014-11-01

    Despite the rapid developments in nanotechnology and biomaterials, the efficient delivery of chemotherapeutic agents is still challenging. Prodrug-based nanoassemblies have many advantages as a potent platform for anticancer drug delivery, such as improved drug availability, high drug loading efficiency, resistance to recrystallization upon encapsulation, and spatially and temporally controllable drug release. In this review, we discuss prodrug-based nanocarriers for cancer therapy, including nanosystems based on polymer-drug conjugates, self-assembling small molecular weight prodrugs and prodrug-encapsulated nanoparticles (NPs). In addition, we discuss new trends in the field of prodrug-based nanoassemblies that enhance the delivery efficiency of anticancer drugs, with special emphasis on smart stimuli-triggered drug release, hybrid nanoassemblies, and combination drug therapy.

  4. 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

  5. Optimizing drugs for local delivery.

    PubMed

    Collingwood, S; Lock, R; Searcey, M

    2009-12-01

    An international panel of speakers together with approximately 70 delegates were brought together by The Society for Medicines Research's symposium on Optimising Drugs for Local Delivery, held on June 11, 2009 at the Novartis Institutes for Biomedical Research, Horsham, UK. The focus of the conference was on the delivery of drugs direct to the site of action and the consequences of this delivery route on delivery technologies, formulation science and molecular design.

  6. Microprocessor controlled transdermal drug delivery.

    PubMed

    Subramony, J Anand; Sharma, Ashutosh; Phipps, J B

    2006-07-06

    Transdermal drug delivery via iontophoresis is reviewed with special focus on the delivery of lidocaine for local anesthesia and fentanyl for patient controlled acute therapy such as postoperative pain. The role of the microprocessor controller in achieving dosimetry, alternating/reverse polarity, pre-programmed, and sensor-based delivery is highlighted. Unique features such as the use of tactile signaling, telemetry control, and pulsatile waveforms in iontophoretic drug delivery are described briefly.

  7. Controlled Drug Delivery Using Microdevices

    PubMed Central

    Sanjay, Sharma T.; Dou, Maowei; Fu, Guanglei; Xu, Feng; Li, XiuJun

    2016-01-01

    Therapeutic drugs administered systematically are evenly distributed to the whole body through blood circulation and have to cross many biological barriers before reaching the pathological site. Conventional drug delivery may make drugs inactive or reduce their potency as they may be hydrolyzed or degraded enzymatically and are rapidly excreted through the urinary system resulting in suboptimal concentration of drugs at the desired site. Controlled drug delivery aims to localize the pharmacological activity of the drug to the desired site at desired release rates. The advances made by micro/nanofluidic technologies have provided new opportunities for better-controlled drug delivery. Various components of a drug delivery system can be integrated within a single tiny micro/nanofluidic chip. This article reviews recent advances of controlled drug delivery made by microfluidic/nanofluidic technologies. We first discuss microreservoir-based drug delivery systems. Then we highlight different kinds of microneedles used for controlled drug delivery, followed with a brief discussion about the current limitations and the future prospects of controlled drug delivery systems. PMID:26813304

  8. Sonophoresis in transdermal drug deliverys.

    PubMed

    Park, Donghee; Park, Hyunjin; Seo, Jongbum; Lee, Seunghun

    2014-01-01

    Transdermal drug delivery (TDD) has several significant advantages compared to oral drug delivery, including elimination of pain and sustained drug release. However, the use of TDD is limited by low skin permeability due to the stratum corneum (SC), the outermost layer of the skin. Sonophoresis is a technique that temporarily increases skin permeability such that various medications can be delivered noninvasively. For the past several decades, various studies of sonophoresis in TDD have been performed focusing on parameter optimization, delivery mechanism, transport pathway, or delivery of several drug categories including hydrophilic and high molecular weight compounds. Based on these various studies, several possible mechanisms of sonophoresis have been suggested. For example, cavitation is believed to be the predominant mechanism responsible for drug delivery in sonophoresis. This review presents details of various studies on sonophoresis including the latest trends, delivery of various therapeutic drugs, sonophoresis pathways and mechanisms, and outlook of future studies.

  9. Nanocarrier mediated delivery of siRNA/miRNA in combination with chemotherapeutic agents for cancer therapy: current progress and advances.

    PubMed

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

    2014-11-28

    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 exhibit 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. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. 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

  11. 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.

  12. MRI in ocular drug delivery.

    PubMed

    Li, S Kevin; Lizak, Martin J; Jeong, Eun-Kee

    2008-11-01

    Conventional pharmacokinetic methods for studying ocular drug delivery are invasive and cannot be conveniently applied to humans. The advancement of MRI technology has provided new opportunities in ocular drug-delivery research. MRI provides a means to non-invasively and continuously monitor ocular drug-delivery systems with a contrast agent or compound labeled with a contrast agent. It is a useful technique in pharmacokinetic studies, evaluation of drug-delivery methods, and drug-delivery device testing. Although the current status of the technology presents some major challenges to pharmaceutical research using MRI, it has a lot of potential. In the past decade, MRI has been used to examine ocular drug delivery via the subconjunctival route, intravitreal injection, intrascleral injection to the suprachoroidal space, episcleral and intravitreal implants, periocular injections, and ocular iontophoresis. In this review, the advantages and limitations of MRI in the study of ocular drug delivery are discussed. Different MR contrast agents and MRI techniques for ocular drug-delivery research are compared. Ocular drug-delivery studies using MRI are reviewed.

  13. MRI in ocular drug delivery

    PubMed Central

    Li, S. Kevin; Lizak, Martin J.; Jeong, Eun-Kee

    2008-01-01

    Conventional pharmacokinetic methods for studying ocular drug delivery are invasive and cannot be conveniently applied to humans. The advancement of MRI technology has provided new opportunities in ocular drug-delivery research. MRI provides a means to non-invasively and continuously monitor ocular drug-delivery systems with a contrast agent or compound labeled with a contrast agent. It is a useful technique in pharmacokinetic studies, evaluation of drug-delivery methods, and drug-delivery device testing. Although the current status of the technology presents some major challenges to pharmaceutical research using MRI, it has a lot of potential. In the past decade, MRI has been used to examine ocular drug delivery via the subconjunctival route, intravitreal injection, intrascleral injection to the suprachoroidal space, episcleral and intravitreal implants, periocular injections, and ocular iontophoresis. In this review, the advantages and limitations of MRI in the study of ocular drug delivery are discussed. Different MR contrast agents and MRI techniques for ocular drug-delivery research are compared. Ocular drug-delivery studies using MRI are reviewed. PMID:18186077

  14. Recent Advances of Cocktail Chemotherapy by Combination Drug Delivery Systems

    PubMed Central

    Hu, Quanyin; Sun, Wujin; Wang, Chao; Gu, Zhen

    2016-01-01

    Combination chemotherapy is widely exploited for enhanced cancer treatment in clinic. However, the traditional cocktail administration of combination regimens often suffers from varying pharmacokinetics among different drugs. The emergence of nanotechnology offers an unparalleled opportunity for developing advanced combination drug delivery strategies with the ability to encapsulate various drugs simultaneously and unify the pharmacokinetics of each drug. This review surveys the most recent advances in combination delivery of multiple small molecule chemotherapeutics using nanocarriers. The mechanisms underlying combination chemotherapy, including the synergistic, additive and potentiation effects, are also discussed with typical examples. We further highlight the sequential and site-specific co-delivery strategies, which provide new guidelines for development of programmable combination drug delivery systems. Clinical outlook and challenges are also discussed in the end. PMID:26546751

  15. Recent advances of cocktail chemotherapy by combination drug delivery systems.

    PubMed

    Hu, Quanyin; Sun, Wujin; Wang, Chao; Gu, Zhen

    2016-03-01

    Combination chemotherapy is widely exploited for enhanced cancer treatment in the clinic. However, the traditional cocktail administration of combination regimens often suffers from varying pharmacokinetics among different drugs. The emergence of nanotechnology offers an unparalleled opportunity for developing advanced combination drug delivery strategies with the ability to encapsulate various drugs simultaneously and unify the pharmacokinetics of each drug. This review surveys the most recent advances in combination delivery of multiple small molecule chemotherapeutics using nanocarriers. The mechanisms underlying combination chemotherapy, including the synergistic, additive and potentiation effects, are also discussed with typical examples. We further highlight the sequential and site-specific co-delivery strategies, which provide new guidelines for development of programmable combination drug delivery systems. Clinical outlook and challenges are also discussed in the end.

  16. Cell-Mediated Drugs Delivery

    PubMed Central

    Batrakova, Elena V.; Gendelman, Howard E.; Kabanov, Alexander V.

    2011-01-01

    INTRODUCTION Drug targeting to sites of tissue injury, tumor or infection with limited toxicity is the goal for successful pharmaceutics. Immunocytes (including mononuclear phagocytes (dendritic cells, monocytes and macrophages), neutrophils, and lymphocytes) are highly mobile; they can migrate across impermeable barriers and release their drug cargo at sites of infection or tissue injury. Thus immune cells can be exploited as trojan horses for drug delivery. AREAS COVERED IN THIS REVIEW This paper reviews how immunocytes laden with drugs can cross the blood brain or blood tumor barriers, to facilitate treatments for infectious diseases, injury, cancer, or inflammatory diseases. The promises and perils of cell-mediated drug delivery are reviewed, with examples of how immunocytes can be harnessed to improve therapeutic end points. EXPERT OPINION Using cells as delivery vehicles enables targeted drug transport, and prolonged circulation times, along with reductions in cell and tissue toxicities. Such systems for drug carriage and targeted release represent a novel disease combating strategy being applied to a spectrum of human disorders. The design of nanocarriers for cell-mediated drug delivery may differ from those used for conventional drug delivery systems; nevertheless, engaging different defense mechanisms into drug delivery may open new perspectives for the active delivery of drugs. PMID:21348773

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

    PubMed Central

    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

  18. Ultrasound mediated transdermal drug delivery.

    PubMed

    Azagury, Aharon; Khoury, Luai; Enden, Giora; Kost, Joseph

    2014-06-01

    Transdermal drug delivery offers an attractive alternative to the conventional drug delivery methods of oral administration and injections. However, the stratum corneum serves as a barrier that limits the penetration of substances to the skin. Application of ultrasound (US) irradiation to the skin increases its permeability (sonophoresis) and enables the delivery of various substances into and through the skin. This review presents the main findings in the field of sonophoresis in transdermal drug delivery as well as transdermal monitoring and the mathematical models associated with this field. Particular attention is paid to the proposed enhancement mechanisms and future trends in the fields of cutaneous vaccination and gene therapy.

  19. Cinnamaldehyde/chemotherapeutic agents interaction and drug-metabolizing genes in colorectal cancer.

    PubMed

    Yu, Chen; Liu, Shen-Lin; Qi, Ming-Hao; Zou, Xi

    2014-02-01

    Cinnamaldehyde is an active monomer isolated from the stem bark of Cinnamomum cassia, a traditional oriental medicinal herb, which is known to possess marked antitumor effects in vitro and in vivo. The aim of the present study was to examine the potential advantages of using cinnamaldehyde in combination with chemotherapeutic agents commonly used in colorectal carcinoma (CRC) therapy, as well as to investigate the effect of cinnamaldehyde on chemotherapeutic-associated gene expression. The synergistic interaction of cinnamaldehyde and chemotherapeutic agents on human CRC HT-29 and LoVo cells was evaluated using the combination index (CI) method. The double staining with Annexin V conjugated to fluorescein-isothiocyanate and phosphatidylserine was employed for apoptosis detection. The expression of drug-metabolizing genes, including excision repair cross‑complementing 1 (ERCC1), orotate phosphoribosyltransferase (OPRT), thymidylate synthase (TS), breast cancer susceptibility gene 1 (BRCA1) and topoisomerase 1 (TOPO1), all in HT-29 and LoVo cells, with or without the addition of cinnamaldehyde, was examined by quantitative polymerase chain reaction (PCR). Cinnamaldehyde had a synergistic effect on the chemotherapeutic agents cytotoxicity in HT-29 and LoVo cells. In addition, cinnamaldehyde suppressed BRCA1, TOPO1, ERCC1 and TS mRNA expression, except for OPRT expression, which was markedly upregulated. Our findings indicate that cinnamaldehyde appears to be a promising candidate as an adjuvant in combination therapy with 5-fluorouracil (5-FU) and oxaliplatin (OXA), two chemotherapeutic agents used in CRC treatment. The possible mechanisms of its action may involve the regulation of drug‑metabolizing genes.

  20. Drug delivery to the ear.

    PubMed

    Hoskison, E; Daniel, M; Al-Zahid, S; Shakesheff, K M; Bayston, R; Birchall, J P

    2013-01-01

    Drug delivery to the ear is used to treat conditions of the middle and inner ear such as acute and chronic otitis media, Ménière's disease, sensorineural hearing loss and tinnitus. Drugs used include antibiotics, antifungals, steroids, local anesthetics and neuroprotective agents. A literature review was conducted searching Medline (1966-2012), Embase (1988-2012), the Cochrane Library and Ovid (1966-2012), using search terms 'drug delivery', 'middle ear', 'inner ear' and 'transtympanic'. There are numerous methods of drug delivery to the middle ear, which can be categorized as topical, systemic (intravenous), transtympanic and via the Eustachian tube. Localized treatments to the ear have the advantages of targeted drug delivery allowing higher therapeutic doses and minimizing systemic side effects. The ideal scenario would be a carrier system that could cross the intact tympanic membrane loaded with drugs or biochemical agents for the treatment of middle and inner ear conditions.

  1. Transmucosal macromolecular drug delivery.

    PubMed

    Prego, C; García, M; Torres, D; Alonso, M J

    2005-01-03

    Mucosal surfaces are the most common and convenient routes for delivering drugs to the body. However, macromolecular drugs such as peptides and proteins are unable to overcome the mucosal barriers and/or are degraded before reaching the blood stream. Among the approaches explored so far in order to optimize the transport of these macromolecules across mucosal barriers, the use of nanoparticulate carriers represents a challenging but promising strategy. The present paper aims to compare the characteristics and potential of nanostructures based on the mucoadhesive polysaccharide chitosan (CS). These are CS nanoparticles, CS-coated oil nanodroplets (nanocapsules) and CS-coated lipid nanoparticles. The characteristics and behavior of CS nanoparticles and CS-coated lipid nanoparticles already reported [A. Vila, A. Sanchez, M. Tobio, P. Calvo, M.J. Alonso, Design of biodegradable particles for protein delivery, J. Control. Rel. 78 (2002) 15-24; R. Fernandez-Urrusuno, P. Calvo, C. Remunan-Lopez, J.L. Vila-Jato, M.J. Alonso, Enhancement of nasal absorption of insulin using chitosan nanoparticles, Pharm. Res. 16 (1999) 1576-1581; M. Garcia-Fuentes, D. Torres, M.J. Alonso, New surface-modified lipid nanoparticles as delivery vehicles for salmon calcitonin (submitted for publication).] are compared with those of CS nanocapsules originally reported here. The three types of systems have a size in the nanometer range and a positive zeta potential that was attributed to the presence of CS on their surface. They showed an important capacity for the association of peptides such as insulin, salmon calcitonin and proteins, such as tetanus toxoid. Their mechanism of interaction with epithelia was investigated using the Caco-2 model cell line. The results showed that CS-coated systems caused a concentration-dependent reduction in the transepithelial resistance of the cell monolayer. Moreover, within the range of concentrations investigated, these systems were internalized in the

  2. Intranasal delivery of antipsychotic drugs.

    PubMed

    Katare, Yogesh K; Piazza, Justin E; Bhandari, Jayant; Daya, Ritesh P; Akilan, Kosalan; Simpson, Madeline J; Hoare, Todd; Mishra, Ram K

    2016-11-29

    Antipsychotic drugs are used to treat psychotic disorders that afflict millions globally and cause tremendous emotional, economic and healthcare burdens. However, the potential of intranasal delivery to improve brain-specific targeting remains unrealized. In this article, we review the mechanisms and methods used for brain targeting via the intranasal (IN) route as well as the potential advantages of improving this type of delivery. We extensively review experimental studies relevant to intranasal delivery of therapeutic agents for the treatment of psychosis and mental illnesses. We also review clinical studies in which intranasal delivery of peptides, like oxytocin (7 studies) and desmopressin (1), were used as an adjuvant to antipsychotic treatment with promising results. Experimental animal studies (17) investigating intranasal delivery of mainstream antipsychotic drugs have revealed successful targeting to the brain as suggested by pharmacokinetic parameters and behavioral effects. To improve delivery to the brain, nanotechnology-based carriers like nanoparticles and nanoemulsions have been used in several studies. However, human studies assessing intranasal delivery of mainstream antipsychotic drugs are lacking, and the potential toxicity of nanoformulations used in animal studies has not been explored. A brief discussion of future directions anticipates that if limitations of low aqueous solubility of antipsychotic drugs can be overcome and non-toxic formulations used, IN delivery (particularly targeting specific tissues within the brain) will gain more importance moving forward given the inherent benefits of IN delivery in comparison to other methods.

  3. 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

  4. Featured Article: Delivery of chemotherapeutic vcMMAE using tobacco mosaic virus nanoparticles.

    PubMed

    Kernan, Daniel L; Wen, Amy M; Pitek, Andrzej S; Steinmetz, Nicole F

    2017-08-01

    The first-line treatment for non-Hodgkin's lymphoma is chemotherapy. While generally well tolerated, off-target effects and chemotherapy-associated complications are still of concern. To overcome the challenges associated with systemic chemotherapy, we developed a biology-inspired, nanoparticle drug delivery system (nanoDDS) making use of the nucleoprotein components of the tobacco mosaic virus (TMV). Virus-based nanoparticles, including the high-aspect ratio soft nanorods formed by TMV, are growing in popularity as nanoDDS due to their simple genetic and chemical engineerability, size and shape tunability, and biocompatibility. In this study, we used bioconjugation to modify TMV as a multivalent carrier for delivery of the antimitotic drug valine-citrulline monomethyl auristatin E (vcMMAE) targeting non-Hodgkin's lymphoma. We demonstrate successful synthesis of the TMV-vcMMAE; data indicate that the TMV-vcMMAE particles remained structurally sound with all of the 2130 identical TMV coat proteins modified to carry the therapeutic payload vcMMAE. Cell uptake using Karpas 299 cells was confirmed with TMV particles trafficking to the endolysosomal compartment, likely allowing for protease-mediated cleavage of the valine-citrulline linker for the release of the active monomethyl auristatin E component. Indeed, effective cell killing of non-Hodgkin's lymphoma in vitro was demonstrated; TMV-vcMMAE was shown to exhibit an IC50 of ∼250 nM. This study contributes to the development of viral nanoDDS. Impact statement Due to side effects associated with systemic chemotherapy, there is an urgent need for the development of novel drug delivery systems. We focus on the high-aspect ratio nanotubes formed by tobacco mosaic virus (TMV) to deliver antimitotic drugs targeted to non-Hodgkin's lymphoma. Many synthetic and biologic nanocarriers are in the development pipeline; the majority of systems are spherical in shape. This may not be optimal, because high-aspect ratio

  5. Drug Delivery Systems for Platinum Drugs

    NASA Astrophysics Data System (ADS)

    Huynh, Vien T.; Scarano, Wei; Stenzel, Martina H.

    2013-09-01

    Since the discovery of cisplatin, drugs based on platinum, have made a significant impact on the treatment of various cancers. The administration of platinum drugs is however accompanied by significant side effects. This chapter discusses the types of drug delivery systems that have been developed in order to enable the targeted delivery while maintaining controlled temporal supply of the drug. The sizes of carriers range from nanometer to micrometer sized particles. The most common types of drug carriers are micelles, liposomes, nanoparticles, and dendrimers, but also a few microspheres have been developed. Most striking aspect of the delivery of platinum drugs is the possibility of physical encapsulation but also the binding of the drug to the polymer carrier coordinate covalent bond. Since platinum drugs have typically two permanent and two leaving ligands, the polymer can be part of either ligand. As the leaving ligand, the platinum drug is released often as cisplatin. If the polymer provides the functionality for the permanent ligand, a new macromolecular drug has been formed. In addition to the attachment of pt(II) drugs, recent offorts are devoted to the conjugation via the Pt((IV) prodrug.

  6. Design, synthesis, and functionalization of nanomaterials for therapeutic drug delivery.

    PubMed

    Grandhi, Taraka Sai Pavan; Rege, Kaushal

    2014-01-01

    Nanomaterials have the potential to solve some of the toughest challenges facing modern medicine. Their unique optical, magnetic and chemical properties at the nanoscale make them different from their macroscale counterparts. Successful application of nanomaterials can revolutionize therapeutics, diagnostics and imaging in several biomedical applications. Self-assembled amphiphilic polymeric nanoparticles have been employed to carry poorly soluble chemotherapeutic drugs. Loading of anticancer chemotherapeutic drugs into self assembled polymeric nanoparticles have shown to increase their circulation time, tumor localization and therapeutic potential. This book chapter provides an introductory discussion to organic nanotechnologies for drug delivery. Promising advances in the field of nanomedicine will be discussed and an outlook to the future will be provided.

  7. 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

  8. Characterization and aerosol dispersion performance of advanced spray-dried chemotherapeutic PEGylated phospholipid particles for dry powder inhalation delivery in lung cancer.

    PubMed

    Meenach, Samantha A; Anderson, Kimberly W; Zach Hilt, J; McGarry, Ronald C; Mansour, Heidi M

    2013-07-16

    Pulmonary inhalation chemotherapeutic drug delivery offers many advantages for lung cancer patients in comparison to conventional systemic chemotherapy. Inhalable particles are advantageous in their ability to deliver drug deep in the lung by utilizing optimally sized particles and higher local drug dose delivery. In this work, spray-dried and co-spray dried inhalable lung surfactant-mimic PEGylated lipopolymers as microparticulate/nanoparticulate dry powders containing paclitaxel were rationally designed via organic solution advanced spray drying (no water) in closed-mode from dilute concentration feed solution. Dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylethanolamine poly(ethylene glycol) (DPPE-PEG) with varying PEG chain length were mixed with varying amounts of paclitaxel in methanol to produce co-spray dried microparticles and nanoparticles. Scanning electron microscopy showed the spherical particle morphology of the inhalable particles. Thermal analysis and X-ray powder diffraction confirmed the retention of the phospholipid bilayer structure in the solid-state following spray drying, the degree of solid-state molecular order, and solid-state phase transition behavior. The residual water content of the particles was very low as quantified analytically Karl Fisher titration. The amount of paclitaxel loaded into the particles was quantified which indicated high encapsulation efficiencies (43-99%). Dry powder aerosol dispersion performance was measured in vitro using the Next Generation Impactor (NGI) coupled with the Handihaler dry powder inhaler device and showed mass median aerodynamic diameters in the range of 3.4-7 μm. These results demonstrate that this novel microparticulate/nanoparticulate chemotherapeutic PEGylated phospholipid dry powder inhalation aerosol platform has great potential in lung cancer drug delivery.

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

    PubMed

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

    2013-12-09

    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.

  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. Phototriggered multifunctional drug delivery device

    NASA Astrophysics Data System (ADS)

    Härtner, S.; Kim, H.-C.; Hampp, N.

    2006-02-01

    Although phototriggered cleavage of chemical bonds induced by single-photon or two-photon-absorption provides attractive tools for controlled drug delivery, the choice of drugs is still limited by the linker system to which the therapeutic molecules need to be bound covalently. The use of a multifunctional linker system suitable for coupling a broad spectrum of drugs to the polymeric carrier will open a new field for drug delivery. We have developed a novel photocleavable multifunctional linker system based on coumarin dimers, whose unique photochemical behavior are well characterized. As a first example, an acrylic polymer-drug conjugate with antimetabolites is explored. The cleavage of the link between the drug and the polymer backbone is triggered by both single- as well as two-photon absorption. The release of the drug is investigated. It is possible to manufacture a polymeric drug delivery device with several drugs in different areas. In particular the two-photon-absorption induced process offers the possibility to address the drug of interest owing to the superior spatial resolution. The key to such devices is a versatile linker-system which can be adopted to work with various drug compounds.

  12. Biodegradable polymers for targeted delivery of anti-cancer drugs.

    PubMed

    Doppalapudi, Sindhu; Jain, Anjali; Domb, Abraham J; Khan, Wahid

    2016-06-01

    Biodegradable polymers have been used for more than three decades in cancer treatment and have received increased interest in recent years. A range of biodegradable polymeric drug delivery systems designed for localized and systemic administration of therapeutic agents as well as tumor-targeting macromolecules has entered into the clinical phase of development, indicating the significance of biodegradable polymers in cancer therapy. This review elaborates upon applications of biodegradable polymers in the delivery and targeting of anti-cancer agents. Design of various drug delivery systems based on biodegradable polymers has been described. Moreover, the indication of polymers in the targeted delivery of chemotherapeutic drugs via passive, active targeting, and localized drug delivery are also covered. Biodegradable polymer-based drug delivery systems have the potential to deliver the payload to the target and can enhance drug availability at desired sites. Systemic toxicity and serious side effects observed with conventional cancer therapeutics can be significantly reduced with targeted polymeric systems. Still, there are many challenges that need to be met with respect to the degradation kinetics of the system, diffusion of drug payload within solid tumors, targeting tumoral tissue and tumor heterogeneity.

  13. Antinuclear antibodies with nucleosome-restricted specificity for targeted delivery of chemotherapeutic agents.

    PubMed

    Torchilin, Vladimir P

    2010-08-01

    Circulating antinuclear autoantibodies (ANAs) are well known to accompany various pathological conditions and can be artificially induced by immunization. Research and clinical data permit us to hypothesize a definite connection between cancer and ANAs. Based on the available data, my group's research suggested that exogenous ANAs may be used as anticancer therapeutics. Among these ANAs, nucleosome-specific ANAs may be particularly useful. Advances in cancer immunotherapy with monoclonal antibodies re-emphasized the role of humoral immunity in neoplasia control. The development of a universal antibody targeting diverse cancers is of clear importance. We showed that certain natural ANAs recognize the surface of numerous tumor cells but not normal cells via cell surface-bound nucleosomes originating from the apoptotically dying neighboring tumor cells, mediate antibody-dependent cellular cytotoxicity of tumor cells in vitro and inhibit the development of murine tumor in syngeneic mice. A single monoclonal antinuclear nucleosome-specific autoantibody, mAb 2C5, specifically recognizes multiple unrelated human tumor cell lines and accumulates at a high tumor-to-normal cell ratio in various human tumors in nude mice. Immunotherapy with mAb 2C5 resulted in significant suppression of the growth of several human tumors. In addition, mAb 2C5, when used in subtherapeutic quantities, can serve as a highly efficient specific ligand to target various drug- or diagnostic agent-loaded pharmaceutical nanocarriers, such as liposomes and polymeric micelles, to various tumors. Here, the data (accumulated predominantly in our laboratory over several years) on mAb 2C5-mediated tumor targeting of chemotherapeutic agents is reviewed.

  14. P-glycoprotein Inhibition for Optimal Drug Delivery

    PubMed Central

    Amin, Md. Lutful

    2013-01-01

    P-glycoprotein (P-gp), an efflux membrane transporter, is widely distributed throughout the body and is responsible for limiting cellular uptake and the distribution of xenobiotics and toxic substances. Hundreds of structurally diverse therapeutic agents are substrates to it and it impedes the absorption, permeability, and retention of the drugs, extruding them out of the cells. It is overexpressed in cancer cells and accountable for obstructing cell internalization of chemotherapeutic agents and for developing transporter mediated resistance by cancer cells during anti-tumor treatments. As it jeopardizes the success of drug delivery and cancer targeting, strategies are being developed to overcome P-gp mediated drug transport. This concise review represents a brief discussion on P-gp mediated drug transport and how it hinders the success of various therapies. Its main focus is on various strategies used to tackle this curb in the field of drug delivery and targeting. PMID:24023511

  15. P-glycoprotein Inhibition for Optimal Drug Delivery.

    PubMed

    Amin, Md Lutful

    2013-08-19

    P-glycoprotein (P-gp), an efflux membrane transporter, is widely distributed throughout the body and is responsible for limiting cellular uptake and the distribution of xenobiotics and toxic substances. Hundreds of structurally diverse therapeutic agents are substrates to it and it impedes the absorption, permeability, and retention of the drugs, extruding them out of the cells. It is overexpressed in cancer cells and accountable for obstructing cell internalization of chemotherapeutic agents and for developing transporter mediated resistance by cancer cells during anti-tumor treatments. As it jeopardizes the success of drug delivery and cancer targeting, strategies are being developed to overcome P-gp mediated drug transport. This concise review represents a brief discussion on P-gp mediated drug transport and how it hinders the success of various therapies. Its main focus is on various strategies used to tackle this curb in the field of drug delivery and targeting.

  16. 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. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Mathematical modeling of drug delivery.

    PubMed

    Siepmann, J; Siepmann, F

    2008-12-08

    Due to the significant advances in information technology mathematical modeling of drug delivery is a field of steadily increasing academic and industrial importance with an enormous future potential. The in silico optimization of novel drug delivery systems can be expected to significantly increase in accuracy and easiness of application. Analogous to other scientific disciplines, computer simulations are likely to become an integral part of future research and development in pharmaceutical technology. Mathematical programs can be expected to be routinely used to help optimizing the design of novel dosage forms. Good estimates for the required composition, geometry, dimensions and preparation procedure of various types of delivery systems will be available, taking into account the desired administration route, drug dose and release profile. Thus, the number of required experimental studies during product development can be significantly reduced, saving time and reducing costs. In addition, the quantitative analysis of the physical, chemical and potentially biological phenomena, which are involved in the control of drug release, offers another fundamental advantage: The underlying drug release mechanisms can be elucidated, which is not only of academic interest, but a pre-requisite for an efficient improvement of the safety of the pharmaco-treatments and for effective trouble-shooting during production. This article gives an overview on the current state of the art of mathematical modeling of drug delivery, including empirical/semi-empirical and mechanistic realistic models. Analytical as well as numerical solutions are described and various practical examples are given. One of the major challenges to be addressed in the future is the combination of mechanistic theories describing drug release out of the delivery systems with mathematical models quantifying the subsequent drug transport within the human body in a realistic way. Ideally, the effects of the design

  18. 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

  19. Potential role of intratumor bacteria in mediating tumor resistance to the chemotherapeutic drug gemcitabine.

    PubMed

    Geller, Leore T; Barzily-Rokni, Michal; Danino, Tal; Jonas, Oliver H; Shental, Noam; Nejman, Deborah; Gavert, Nancy; Zwang, Yaara; Cooper, Zachary A; Shee, Kevin; Thaiss, Christoph A; Reuben, Alexandre; Livny, Jonathan; Avraham, Roi; Frederick, Dennie T; Ligorio, Matteo; Chatman, Kelly; Johnston, Stephen E; Mosher, Carrie M; Brandis, Alexander; Fuks, Garold; Gurbatri, Candice; Gopalakrishnan, Vancheswaran; Kim, Michael; Hurd, Mark W; Katz, Matthew; Fleming, Jason; Maitra, Anirban; Smith, David A; Skalak, Matt; Bu, Jeffrey; Michaud, Monia; Trauger, Sunia A; Barshack, Iris; Golan, Talia; Sandbank, Judith; Flaherty, Keith T; Mandinova, Anna; Garrett, Wendy S; Thayer, Sarah P; Ferrone, Cristina R; Huttenhower, Curtis; Bhatia, Sangeeta N; Gevers, Dirk; Wargo, Jennifer A; Golub, Todd R; Straussman, Ravid

    2017-09-15

    Growing evidence suggests that microbes can influence the efficacy of cancer therapies. By studying colon cancer models, we found that bacteria can metabolize the chemotherapeutic drug gemcitabine (2',2'-difluorodeoxycytidine) into its inactive form, 2',2'-difluorodeoxyuridine. Metabolism was dependent on the expression of a long isoform of the bacterial enzyme cytidine deaminase (CDDL), seen primarily in Gammaproteobacteria. In a colon cancer mouse model, gemcitabine resistance was induced by intratumor Gammaproteobacteria, dependent on bacterial CDDL expression, and abrogated by cotreatment with the antibiotic ciprofloxacin. Gemcitabine is commonly used to treat pancreatic ductal adenocarcinoma (PDAC), and we hypothesized that intratumor bacteria might contribute to drug resistance of these tumors. Consistent with this possibility, we found that of the 113 human PDACs that were tested, 86 (76%) were positive for bacteria, mainly Gammaproteobacteria. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  20. MEK inhibitor enhances sensitivity to chemotherapeutic drugs in multidrug resistant hepatocellular carcinoma cells.

    PubMed

    Meng, Qingliang; He, Xiaoqi; Xie, Guangwei; Tian, Qingzhong; Shu, Xiaogang; Li, Jin; Xiao, Yong

    2017-09-01

    The aim of the present study was to investigate the association between the mitogen-activated protein kinase (MAPK) signal transduction pathway and multidrug resistance in hepatocellular carcinoma cells. A Cell Counting Kit-8 assay was used to determine the drug sensitivity of HepG2 and HepG2/ADM hepatocellular carcinoma cell lines in combination with the MAPK/extracellular-signal-regulated kinase kinase (MEK) inhibitor U0126. Flow cytometry was used to analyze the rate of apoptosis. The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP1) mRNA expression following treatment with various concentrations of U0126. P-gp and MRP1 expression levels were measured using Western blot analysis. The half-maximal inhibitory concentration was markedly decreased in combination with U0126. RT-qPCR results demonstrated that the expression of multidrug resistance 1 (MDR1) and MRP1 in HepG2/ADM cells was increased 5.37- and 6-14-fold compared with that in HepG2 cells. Furthermore, the expression levels in HepG2/ADM cells were decreased following U0126 treatment in a dose-dependent manner. The expression of P-gp and MRP1 in HepG2/ADM cells was increased 2.68- and 2.76-fold compared with that in HepG2 cells. Furthermore, the expression levels in HepG/ADM cells were decreased following U0126 treatment in a dose-dependent manner. The results of the present study indicate that the MEK inhibitor U0126 enhances sensitivity to chemotherapeutic drugs by downregulating P-gp and MRP1 expression in resistant hepatocellular carcinoma cells. The combination of MEK inhibitor and conventional chemotherapeutic drugs may provide novel therapeutic prospects for the treatment of drug-resistant hepatocellular carcinoma.

  1. Evaluation of environmental contaminations and occupational exposures involved in preparation of chemotherapeutic drugs.

    PubMed

    Maeda, Shinichiro; Miyawaki, Koji; Matsumoto, Shoji; Oishi, Masako; Miwa, Yoshihiro; Kurokawa, Nobuo

    2010-06-01

    Many healthcare workers are concerned about the risk of occupational exposures to hazardous drugs. The Japanese Society of Hospital Pharmacists (JSHP) revised the "Guidelines for the Handling of Antineoplastic Drugs in Hospitals", however, the precautions and awareness of handling drugs varied in institutions. We assessed the levels of environmental contaminations in our hospital and urinary excretion of cyclophosphamide (CP) and ifosfamide (IF) in pharmacists and nurses. In environmental studies, we obtained samples by wiping the surfaces around two biological safety cabinets (BSCs) on eight days for four months. One BSC was equipped in hospital pharmacy and the other was equipped in an oncology ward, and used for preparing chemotherapeutic drugs for outpatients and for inpatients, respectively. We obtained the urine samples from 6 pharmacists and 2 nurses. We used solid phase extraction (SPE) as a convenient extraction procedure and liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) for the analysis of the samples. CP was detected on the working surfaces inside both BSCs, and detected at low levels on the back surfaces of the BSCs and at the working tables around the BSCs. IF over the LLOQ was not detected in both BSCs. CP and IF were not detected in all urine samples of pharmacists and nurses. Detection frequencies and amounts of these drugs were low levels, compared with previous reports in Japan, and our results showed that improving awareness about handling hazardous drugs could reduce the risk of the occupational exposures.

  2. Strategies for targeted drug delivery in treatment of colon cancer: current trends and future perspectives.

    PubMed

    Banerjee, Antara; Pathak, Surajit; Subramanium, Vimala Devi; G, Dharanivasan; Murugesan, Ramachandran; Verma, Rama S

    2017-08-01

    Despite advances in treatment modalities, colon cancer (CC) is the third most common cause of cancer-related death worldwide. Subsequent unfavorable effects owing to toxicity of conventional drugs are a challenging problem associated with chemotherapy. There is noticeable concern toward site-specific/targeted delivery of chemotherapeutic drugs specifically to the affected site of the colon in a predictable and reproducible manner. However, the biggest challenge in successful drug targeting for the colon is avoidance of drug absorption and/or degradation in the upper gastrointestinal tract before the drug reaches the colon. Nanoparticles endowed with targeting abilities offer a novel approach for site-specific delivery of chemotherapeutic agents. The present review focuses on recent approaches for colon-specific drug delivery (CDDS) and aims to unveil the emerging possibilities and advances in the treatment of CC with CDDS. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. 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

    2015-11-10

    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.

  4. Implantable drug-delivery systems.

    PubMed

    Blackshear, P J

    1979-12-01

    Implantable drug-delivery systems are being developed to release drugs to the bloodstream continuously as well as free patients from being hospitalized to receive intravenous infusions or frequent injections. One technique is implantation of a pellet in the subcutaneous tissue so the pellet may be released by erosion. Drugs are also diffused through silicone rubber capsules but only polyacrylamide is able to release large molecules. Contraceptive rings containing progesterone and placed in the uterus or vagina and implanted silicone-rubber capsules use these principles. Disadvantages to the subcutaneous delivery of drugs include: 1) release of the drug in subcutaneous tissue rather than in the bloodstream directly; 2) entry into the circulatory system is controlled by surrounding blood supplies which vary with fat; 3) diffusion may be difficult due to dense layers of fibrous tissue; and 4) drug amounts cannot be readily regulated. The Ommaya reservoir uses a container with a self-sealing membrane implanted in the scalp and connected to a cerebral ventricle to treat forms of leukemia and fungal meningitis. Another development is an implantable disk-shaped infusion pump with 2 compartments, the outer one containing a propellant and the inner chamber containing the drug, holds 45 milliliters and releases about 1 milliliter/day. In the future these systems may release drugs in response to biochemical feedback or deliver a drug to 1 specific area.

  5. 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. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. 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. ©2011 AACR.

  7. 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

  8. 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

  9. Mathematical models of the steps involved in the systemic delivery of a chemotherapeutic to a solid tumor: From circulation to survival.

    PubMed

    Ulmschneider, Martin B; Searson, Peter C

    2015-08-28

    The efficacy of an intravenously administered chemotherapeutic for treatment of a solid tumor is dependent on a sequence of steps, including circulation, extravasation by the enhanced permeability and retention effect, transport in the tumor microenvironment, the mechanism of cellular uptake and trafficking, and the mechanism of drug action. These steps are coupled since the time dependent concentration in circulation determines the concentration and distribution in the tumor microenvironment, and hence the amount taken up by individual cells within the tumor. Models have been developed for each of the steps in the delivery process although their predictive power remains limited. Advances in our understanding of the steps in the delivery process will result in refined models with improvements in predictive power and ultimately allow the development of integrated models that link systemic administration of a drug to the probability of survival. Integrated models that predict outcomes based on patient specific data could be used to select the optimum therapeutic regimens. Here we present an overview of current models for the steps in the delivery process and highlight knowledge gaps that are key to developing integrated models.

  10. [Development of drug resistance and the cross resistance in Shigella to certain chemotherapeutic preparations in vitro].

    PubMed

    Chernomordik, A B; Bass, T M; Ozerianskaia, N M; Mukhorskaia, V A; Rzhanova, V I

    1976-09-01

    A total of 700 Shigella cultures isolated in different regions of the Ukraine in 1974 and occasionally in 1971-1973 were studied. No cultures resistant to furazolidone or enteroseptol were found. Under the experimental conditions resistance to nitrofuran and especially oxycholine preparations in Shigella developed slowly when the cultures were passaged in broths with increasing concentrations of the drugs. Cross resistance in Shigella was observed with respect to (a) various nitrofuran preparations, less pronounced with respect to furacryline and (b) enteroseptol and 5-NOK. No cross resistance was noted between the above groups of the chemotherapeutics and levomycetin and tetracycline. 5-NOK inhibited the resistance development to streptomycin, while enteroseptol inhibited the development of resistance to furazolidone in Shigella. The studies showed that in the near future there will be observed no mass development of resistance to furazolidone and enteroseptol in Shigella.

  11. Trypanothione Reductase: A Viable Chemotherapeutic Target for Antitrypanosomal and Antileishmanial Drug Design

    PubMed Central

    Khan, M. Omar F.

    2007-01-01

    Trypanosomiasis and leishmaniasis are two debilitating disease groups caused by parasites of Trypanosoma and Leishmania spp. and affecting millions of people worldwide. A brief outline of the potential targets for rational drug design against these diseases are presented, with an emphasis placed on the enzyme trypanothione reductase. Trypanothione reductase was identified as unique to parasites and proposed to be an effective target against trypanosomiasis and leishmaniasis. The biochemical basis of selecting this enzyme as a target, with reference to the simile and contrast to human analogous enzyme glutathione reductase, and the structural aspects of its active site are presented. The process of designing selective inhibitors for the enzyme trypanothione reductase has been discussed. An overview of the different chemical classes of inhibitors of trypanothione reductase with their inhibitory activities against the parasites and their prospects as future chemotherapeutic agents are briefly revealed. PMID:21901070

  12. Drug-induced histone eviction from open chromatin contributes to the chemotherapeutic effects of doxorubicin

    PubMed Central

    Pang, Baoxu; Qiao, Xiaohang; Janssen, Lennert; Velds, Arno; Groothuis, Tom; Kerkhoven, Ron; Nieuwland, Marja; Ovaa, Huib; Rottenberg, Sven; van Tellingen, Olaf; Janssen, Jeroen; Huijgens, Peter; Zwart, Wilbert; Neefjes, Jacques

    2013-01-01

    DNA topoisomerase II inhibitors are a major class of cancer chemotherapeutics, which are thought to eliminate cancer cells by inducing DNA double-strand breaks. Here we identify a novel activity for the anthracycline class of DNA topoisomerase II inhibitors: histone eviction from open chromosomal areas. We show that anthracyclines promote histone eviction irrespective of their ability to induce DNA double-strand breaks. The histone variant H2AX, which is a key component of the DNA damage response, is also evicted by anthracyclines, and H2AX eviction is associated with attenuated DNA repair. Histone eviction deregulates the transcriptome in cancer cells and organs such as the heart, and can drive apoptosis of topoisomerase-negative acute myeloid leukaemia blasts in patients. We define a novel mechanism of action of anthracycline anticancer drugs doxorubicin and daunorubicin on chromatin biology, with important consequences for DNA damage responses, epigenetics, transcription, side effects and cancer therapy. PMID:23715267

  13. 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

  14. Potential chemotherapeutic targets for Japanese encephalitis: current status of antiviral drug development and future challenges.

    PubMed

    Ishikawa, Tomohiro; Konishi, Eiji

    2015-01-01

    Japanese encephalitis (JE) remains a public health threat in Asia. Although several vaccines have been licensed, ∼ 67,900 cases of the disease are estimated to occur annually, probably because the vaccine coverage is low. Therefore, effective antiviral drugs are required to control JE. However, no licensed anti-JE drugs are available, despite extensive efforts to develop them. We provide a general overview of JE and JE virus, including its transmission cycle, distribution, structure, replication machinery, immune evasion mechanisms and vaccines. The current situation in antiviral drug development is then reviewed and future perspectives are discussed. Although the development of effective anti-JE drugs is an urgent issue, only supportive care is currently available. Recent progress in our understanding of the viral replication machinery and immune evasion strategies has identified new targets for anti-JE drug development. To date, most candidate drugs have only been evaluated in single-drug formulations, and efficient drug delivery to the CNS has virtually not been considered. However, an effective anti-JE treatment is expected to be achieved with multiple-drug formulations and a targeted drug delivery system in the near future.

  15. Transgenic plants as low-cost platform for chemotherapeutic drugs screening.

    PubMed

    Vergara, Daniele; de Domenico, Stefania; Maffia, Michele; Piro, Gabriella; Di Sansebastiano, Gian-Pietro

    2015-01-20

    In this work we explored the possibility of using genetically modified Arabidopsis thaliana plants as a rapid and low-cost screening tool for evaluating human anticancer drugs action and efficacy. Here, four different inhibitors with a validated anticancer effect in humans and distinct mechanism of action were screened in the plant model for their ability to interfere with the cytoskeletal and endomembrane networks. We used plants expressing a green fluorescent protein (GFP) tagged microtubule-protein (TUA6-GFP), and three soluble GFPs differently sorted to reside in the endoplasmic reticulum (GFPKDEL) or to accumulate in the vacuole through a COPII dependent (AleuGFP) or independent (GFPChi) mechanism. Our results demonstrated that drugs tested alone or in combination differentially influenced the monitored cellular processes including cytoskeletal organization and endomembrane trafficking. In conclusion, we demonstrated that A. thaliana plants are sensitive to the action of human chemotherapeutics and can be used for preliminary screening of drugs efficacy. The cost-effective subcellular imaging in plant cell may contribute to better clarify drugs subcellular targets and their anticancer effects.

  16. Drug delivery by lipid cochleates.

    PubMed

    Zarif, Leila

    2005-01-01

    Drug delivery technology has brought additional benefits to pharmaceuticals such as reduction in dosing frequency and side effects, as well as the extension of patient life. To address this need, cochleates, a precipitate obtained as a result of the interaction between phosphatidylserine and calcium, have been developed and proved to have potential in encapsulating and delivering small molecule drugs. This chapter discusses the molecules that can be encapsulated in a cochleate system and describes in detail the methodology that can be used to encapsulate and characterize hydrophobic drugs such as amphotericin B, a potent antifungal agent. Some efficacy data in animal models infected with candidiasis or aspergillosis are described as well.

  17. 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.

  18. 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.

  19. Cell cycle arrest and clonogenic tumor cell kill by divergent chemotherapeutic drugs.

    PubMed

    Mastbergen, S C; Duivenvoorden, I; Versteegh, R T; Geldof, A A

    2000-01-01

    Regulators of cell cycle phase transitions could be important targets for cancer treatment using cytostatic chemotherapy. Therefore, the extent of cell cycle arrest induced by different cytostatic agents has to be correlated with ultimate clonogenic tumor cell death. Especially the value of early cell cycle perturbations as indicators for the clinical efficacy of drugs should be a matter of investigation. In vitro PC-3 human prostate carcinoma cells were incubated for 24 hours with a panel of six different chemotherapeutic drugs in various concentrations (Aplidine, Cisplatin, Isohomohalichondrin B (IHB), Taxol, Vincristine and Vinorelbine). The short term effects on the cell cycle distribution were determined by DNA flowcytometry while the clonogenic capacity of these cells was quantitated to measure the cytotoxic treatment efficacy. Significant decreases of clonogenic survival proved to be strongly correlated with cell cycle perturbations. IHB, Taxol, Vincristine and Vinorelbine resulted in accumulation (up to 87-92%) in the G2M phase, while Cisplatin and Aplidine led to increases in the S-phase fraction and in both G2M- as well as S-phase fractions, respectively. Cell cycle phase perturbations appear to be suitable, early markers for cytotoxic drug efficacy.

  20. Enhancing chemotherapeutic drug inhibition on tumor growth by ultrasound: an in vivo experiment.

    PubMed

    Zhao, Ying-Zheng; Lu, Cui-Tao; Zhou, Zhi-Cai; Jin, Zhuo; Zhang, Lu; Sun, Chang-Zheng; Xu, Yan-Yan; Gao, Hui-Sheng; Tian, Ji-Lai; Gao, Feng-Hou; Tang, Qin-Qin; Li, Wei; Xiang, Qi; Li, Xiao-Kun; Li, Wen-Feng

    2011-02-01

    An in vivo study on enhancing epirubicin hydrochloride (EPI) inhibition on tumor growth by ultrasound (US) was reported. Five-week-old male nude mice were used and HL-60 cells were s.c. (subcutaneous injection) inoculated in axilla of these mice. Six groups were designed and five consecutive treatments were applied to investigate the inhibition on tumor growth and body weight growth. US applied locally to the tumor resulted in a substantially increased drug uptake in tumor cells. The inhibition on tumor growth depended on the position of drug injection and phospholipid-based microbubble (PMB) application. Tumor growth rate under group 1 (PMB+US) was similar to that of blank control. The order of the inhibition on tumor volume growth was: group 4 (s.c. EPI+PMB+US) > group 5 intraperitoneal (i.p. EPI+PMB+US) > group 2 (i.p. EPI) > group 3 (s.c. EPI+US) > group 1 (PMB+US). Similar conclusion was obtained from experimental measurements of tumor weight change. The order of animal survival status for EPI administration groups was: group 4 > group 5 > group 2 > group 3. Chemotherapeutic drug inhibition on tumor growth could be enhanced by local US combined with PMB, which might provide a potential application for US-mediated chemotherapy.

  1. Facile Generation of Tumor-pH-Labile Linkage-Bridged Block Copolymers for Chemotherapeutic Delivery.

    PubMed

    Sun, Chun-Yang; Liu, Yang; Du, Jin-Zhi; Cao, Zhi-Ting; Xu, Cong-Fei; Wang, Jun

    2016-01-18

    Successful bench-to-bedside translation of nanomedicine relies heavily on the development of nanocarriers with superior therapeutic efficacy and high biocompatibility. However, the optimal strategy for improving one aspect often conflicts with the other. Herein, we report a tactic of designing tumor-pH-labile linkage-bridged copolymers of clinically validated poly(D,L-lactide) and poly(ethylene glycol) (PEG-Dlink(m)-PDLLA) for safe and effective drug delivery. Upon arriving at the tumor site, PEG-Dlink(m)-PDLLA nanoparticles will lose the PEG layer and increase zeta potential by responding to tumor acidity, which significantly enhances cellular uptake and improves the in vivo tumor inhibition rate to 78.1% in comparison to 47.8% of the non-responsive control. Furthermore, PEG-Dlink(m)-PDLLA nanoparticles show comparable biocompatibility with the clinically used PEG-b-PDLLA micelle. The improved therapeutic efficacy and safety demonstrate great promise for our strategy in future translational studies.

  2. 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.

  3. 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

  4. Food, physiology and drug delivery.

    PubMed

    Varum, F J O; Hatton, G B; Basit, A W

    2013-12-05

    Gastrointestinal physiology is dynamic and complex at the best of times, and a multitude of known variables can affect the overall bioavailability of drugs delivered via the oral route. Yet while the influences of food and beverage intake as just two of these variables on oral drug delivery have been extensively documented in the wider literature, specific information on their effects remains sporadic, and is not so much contextually reviewed. Food co-ingestion with oral dosage forms can mediate several changes to drug bioavailability, yet the precise mechanisms underlying this have yet to be fully elucidated. Likewise, the often detrimental effects of alcohol (ethanol) on dosage form performance have been widely observed experimentally, but knowledge of which has only moderately impacted on clinical practice. Here, we attempt to piece together the available subject matter relating to the influences of both solid and liquid foodstuffs on the gastrointestinal milieu and the implications for oral drug delivery, with particular emphasis on the behaviour of modified-release dosage forms, formulation robustness and drug absorption. Providing better insight into these influences, and exemplifying cases where formulations have been developed or modified to circumvent their associated problems, can help to appropriately direct the design of future in vitro digestive modelling systems as well as oral dosage forms resilient to these effects. Moreover, this will help to better our understanding of the impact of food and alcohol intake on normal gut behaviour and function.

  5. Dacarbazine in melanoma: from a chemotherapeutic drug to an immunomodulating agent.

    PubMed

    Ugurel, Selma; Paschen, Annette; Becker, Jürgen C

    2013-02-01

    Chemotherapeutic drugs are clinically used to treat cancer because of their cytotoxic activities against tumor cells. Recently, however, evidence is accumulating-including the report of Hervieu et al. (2012) in the current issue of The Journal of Investigative Dermatology-indicating that at least some of these drugs have broader activities and that they should also be considered immunomodulatory agents. Indeed, Hervieu demonstrates that dacarbazine (DTIC) exerts immunostimulatory effects by inducing local activation of natural killer (NK) and T cells, suggesting that upon treatment with DTIC, the tumor participates in the initiation of an immune response: (i) DTIC treatment elicits the expression of ligands of the immunoreceptor NKG2D on melanoma cells; (ii) engagement of the ligands by NKG2D on NK cells leads to their activation, allowing enhanced tumor-cell killing and the release of IFN-γ; and (iii) IFN-γ in turn upregulates major histocompatibility complex class I expression on tumor cells, which favors their recognition by cytotoxic CD8+ T lymphocytes (CTLs).

  6. 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

  7. Repurposing the FDA-approved pinworm drug pyrvinium as a novel chemotherapeutic agent for intestinal polyposis.

    PubMed

    Li, Bin; Flaveny, Colin A; 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.

  8. Chemotherapeutic drug-induced ABCG2 promoter demethylation as a novel mechanism of acquired multidrug resistance.

    PubMed

    Bram, Eran E; Stark, Michal; Raz, Shachar; Assaraf, Yehuda G

    2009-12-01

    ABCG2 is an efflux transporter conferring multidrug resistance (MDR) on cancer cells. However, the initial molecular events leading to its up-regulation in MDR tumor cells are poorly understood. Herein, we explored the impact of drug treatment on the methylation status of the ABCG2 promoter and consequent reactivation of ABCG2 gene expression in parental tumor cell lines and their MDR sublines. We demonstrate that ABCG2 promoter methylation is common in T-cell acute lymphoblastic leukemia (T-ALL) lines, also present in primary T-ALL lymphoblast specimens. Furthermore, drug selection with sulfasalazine and topotecan induced a complete demethylation of the ABCG2 promoter in the T-ALL and ovarian carcinoma model cell lines CCRF-CEM and IGROV1, respectively. This resulted in a dramatic induction of ABCG2 messenger RNA levels (235- and 743-fold, respectively) and consequent acquisition of an ABCG2-dependent MDR phenotype. Quantitative genomic polymerase chain reaction and ABCG2 promoter-luciferase reporter assay did not reveal ABCG2 gene amplification or differential transcriptional trans-activation, which could account for ABCG2 up-regulation in these MDR cells. Remarkably, mimicking cytotoxic bolus drug treatment through 12- to 24-hour pulse exposure of ABCG2-silenced leukemia cells, to clinically relevant concentrations of the chemotherapeutic agents daunorubicin and mitoxantrone, resulted in a marked transcriptional up-regulation of ABCG2. Our findings establish that antitumor drug-induced epigenetic reactivation of ABCG2 gene expression in cancer cells is an early molecular event leading to MDR. These findings have important implications for the emergence, clonal selection, and expansion of malignant cells with the MDR phenotype during chemotherapy.

  9. 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

  10. Thermosensitive polymers for drug delivery

    SciTech Connect

    Gutowska, A.; Kim, Sung Wan

    1996-12-31

    Thermosensitive polymers (TSP) demonstrating temperature-dependent temperature-dependent swelling in water have been extensively studied in recent years. Their molecular and physical properties have been tailored for a variety of biomedical and engineering uses. This presentation will discuss TSP based on poly(N-isopropylacrylamide) and its crosslinked networks modified with hydrophobic or hydrophilic components by copolymerization blending and formation of interpenetrating polymer networks (IPNs). TSP designed for three different areas of drug delivery will be presented. First, heparin releasing temperature-sensitive polymers for the prevention of surface induced thrombosis will be presented as an example of a local macromolecular delivery from a surface of a medical device. Second, a new oral delivery device based on a novel mechanical squeezing concept, utilizing specific swelling-deswelling characteristics of temperature- and temperature/pH-sensitive hydrogels will be described. These hydrogels were synthesized to exhibit a controlled swelling-deswelling kinetics, hence a variety of release profiles may be generated: a delayed, a zero-order or an {open_quotes}on-off{close_quotes} release profile. Finally, thermally reversible polymeric gels as an extracellular matrix for the entrapment of pancreatic islet cells in biohybrid artificial pancreas for insulin delivery will be discussed.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. Enhancement of radiation and chemotherapeutic drug responses by 2-deoxy-D-glucose in animal tumors.

    PubMed

    Gupta, Seema; Farooque, Abdullah; Adhikari, J S; Singh, Saurabh; Dwarakanath, B S

    2009-09-01

    The development of an approach based on the energy-linked modification of DNA repair and cellular recovery processes using 2-deoxy-D-glucose (2-DG; inhibitor of glycolytic ATP production) has shown promising results in a number of model systems of cancer. Following encouraging results on the tolerance and toxicity (acute as well as late effects) of the combination (2-DG and hypofractionated radiotherapy) in Phase I and II clinical trials, its efficacy is currently under evaluation in Phase III clinical trials for glioma patients. Since heterogeneous physiologic and metabolic status in tumors as well as host-tumor interactions influence the local tumor control, which coupled with systemic disturbances could determine the cure (long-term tumor free survival), investigations on the in vivo responses of tumors to the combined treatment have received considerable attention. This communication provides a brief overview on the in vivo studies related to radio- and chemosensitization of tumors by 2-DG, besides the normal tissue toxicity induced by the combined treatment of 2-DG and radiation or chemotherapeutic drugs.

  16. 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.

  17. 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

  18. Methylseleninic acid potentiates apoptosis induced by chemotherapeutic drugs in androgen-independent prostate cancer cells.

    PubMed

    Hu, Hongbo; Jiang, Cheng; Ip, Clement; Rustum, Youcef M; Lü, Junxuan

    2005-03-15

    To test whether and how selenium enhances the apoptosis potency of selected chemotherapeutic drugs in prostate cancer (PCA) cells. DU145 and PC3 human androgen-independent PCA cells were exposed to minimal apoptotic doses of selenium and/or the topoisomerase I inhibitor 7-ethyl-10-hydroxycamptothecin (SN38), the topoisomerase II inhibitor etoposide or the microtubule inhibitor paclitaxel/taxol. Apoptosis was measured by ELISA for histone-associated DNA fragments, by flow cytometric analysis of sub-G(1) fraction, and by immunoblot analysis of cleaved poly(ADP-ribose)polymerase. Pharmacologic inhibitors were used to manipulate caspases and c-Jun-NH(2)-terminal kinases (JNK). The methylselenol precursor methylseleninic acid (MSeA) increased the apoptosis potency of SN38, etoposide, or paclitaxel by several folds higher than the expected sum of the apoptosis induced by MSeA and each drug alone. The combination treatment did not further enhance JNK1/2 phosphorylation that was induced by each drug in DU145 cells. The JNK inhibitor SP600125 substantially decreased the activation of caspases and apoptosis induced by MSeA combination with SN38 or etoposide and completely blocked these events induced by MSeA/paclitaxel. The caspase-8 inhibitor zIETDfmk completely abolished apoptosis and caspase-9 and caspase-3 cleavage, whereas the caspase-9 inhibitor zLEHDfmk significantly decreased caspase-3 cleavage and apoptosis but had no effect on caspase-8 cleavage. None of these caspase inhibitors abolished JNK1/2 phosphorylation. A JNK-independent suppression of survivin by SN38 and etoposide, but not by paclitaxel, was also observed. In contrast to MSeA, selenite did not show any enhancing effect on the apoptosis induced by these drugs. MSeA enhanced apoptosis induced by cancer therapeutic drugs in androgen-independent PCA cells. In DU145 cells, the enhancing effect was primarily through interactions between MSeA and JNK-dependent targets to amplify the caspase-8-initiated

  19. Reduced mtDNA copy number increases the sensitivity of tumor cells to chemotherapeutic drugs

    PubMed Central

    Mei, H; Sun, S; Bai, Y; Chen, Y; Chai, R; Li, H

    2015-01-01

    Many cancer drugs are toxic to cells by activating apoptotic pathways. Previous studies have shown that mitochondria have key roles in apoptosis in mammalian cells, but the role of mitochondrial DNA (mtDNA) copy number variation in the pathogenesis of tumor cell apoptosis remains largely unknown. We used the HEp-2, HNE2, and A549 tumor cell lines to explore the relationship between mtDNA copy number variation and cell apoptosis. We first induced apoptosis in three tumor cell lines and one normal adult human skin fibroblast cell line (HSF) with cisplatin (DDP) or doxorubicin (DOX) treatment and found that the mtDNA copy number significantly increased in apoptotic tumor cells, but not in HSF cells. We then downregulated the mtDNA copy number by transfection with shRNA-TFAM plasmids or treatment with ethidium bromide and found that the sensitivity of tumor cells to DDP or DOX was significantly increased. Furthermore, we observed that levels of reactive oxygen species (ROS) increased significantly in tumor cells with lower mtDNA copy numbers, and this might be related to a low level of antioxidant gene expression. Finally, we rescued the increase of ROS in tumor cells with lipoic acid or N-acetyl-L-cysteine and found that the apoptosis rate decreased. Our studies suggest that the increase of mtDNA copy number is a self-protective mechanism of tumor cells to prevent apoptosis and that reduced mtDNA copy number increases ROS levels in tumor cells, increases the tumor cells' sensitivity to chemotherapeutic drugs, and increases the rate of apoptosis. This research provides evidence that mtDNA copy number variation might be a promising new therapeutic target for the clinical treatment of tumors. PMID:25837486

  20. Drug delivery systems from nose to brain.

    PubMed

    Misra, Ambikanandan; Kher, Gitanjali

    2012-09-01

    The treatment of brain disorders is particularly challenging due to the presence of a variety of formidable obstacles to deliver drugs selectively and effectively to the brain. Blood-brain-barrier (BBB) constitutes the major obstacle to the uptake of drugs into the brain following systemic administration. Intranasal delivery offers a non-invasive and convenient method to bypass the BBB and delivery of therapeutics directly to the brain. The review discusses the potential of intranasal route to deliver drugs to the brain, the mechanisms and pathways of direct nose to brain drug transport, the various factors influencing transnasal drug absorption, the conventional and novel intranasal drug delivery systems, the various intranasal drug delivery techniques and devices, and examples of brain drug transport that have been feasible in treating various brain disorders. Moreover, products on the market, investigational drugs, and the author's perceptions about the prospect of intranasal delivery for treating brain disorders are also been discussed.

  1. 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

  2. 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

  3. Device-assisted transdermal drug delivery.

    PubMed

    Lee, Hyunjae; Song, Changyeong; Baik, Seungmin; Kim, Dokyoon; Hyeon, Taeghwan; Kim, Dae-Hyeong

    2017-09-01

    Transdermal drug delivery is a prospective drug delivery strategy to complement the limitations of conventional drug delivery systems including oral and injectable methods. This delivery route allows both convenient and painless drug delivery and a sustained release profile with reduced side effects. However, physiological barriers in the skin undermine the delivery efficiency of conventional patches, limiting drug candidates to small-molecules and lipophilic drugs. Recently, transdermal drug delivery technology has advanced from unsophisticated methods simply relying on natural diffusion to drug releasing systems that dynamically respond to external stimuli. Furthermore, physical barriers in the skin have been overcome using microneedles, and controlled delivery by wearable biosensors has been enabled ultimately. In this review, we classify the evolution of advanced drug delivery strategies based on generations and provide a comprehensive overview. Finally, the recent progress in advanced diagnosis and therapy through customized drug delivery systems based on real-time analysis of physiological cues is highlighted. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Colloidal drug delivery systems in vaccine delivery.

    PubMed

    Beg, Sarwar; Samad, Abdus; Nazish, Iram; Sultana, Ruksar; Rahman, Mahfoozur; Ahmad, Md Zaki; Akbar, Md

    2013-01-01

    Vaccines play a vital role in the field of community medicine to combat against several diseases of human existence. Vaccines primarily trigger the acquired immune system to develop long-lasting immunity against pathogens. Conventional approaches for vaccine delivery lacks potential to target a particular antigen to develop acquired immunity by specific antibodies. Recent advancements in vaccine delivery showed that inclusion of adjuvants in vaccine formulations or delivery of them in a carrier helps in achieving desired targeting ability, reducing the immunogenicity and significant augmentation in the immune response. Colloidal carriers (liposomes, niosomes, microspheres, proteosomes, virosomes and virus like particles (VLPs), antigen cochleates, dendrimers and carbon nanotubes) have been widely explored for vaccine delivery. Further, surface engineering of these carriers with ligands, functional moieties and monoclonal antibodies tend to enhance the immune recognition potential of vaccines by differentiation of antigen specific memory T-cells. The current review, therefore, provides an updated account on the recent advancements in various colloidal delivery systems in vaccine delivery, outlining the mechanism of immune response initiated by them along with potential applications and marketed instances in an explicit manner.

  5. Association between MDR1 gene of gastrointestinal tumors, the expression of P-glycoprotein and resistance to chemotherapeutic drugs.

    PubMed

    Su, Jian-Li; Wang, Cheng-Hong; Kang, Hong-Gang; Zhang, Jing; Wang, Bao-Zhong; Liu, Mei-Rong; Zhao, Jun; Liu, Lin

    2017-09-01

    The aim of the present study was to examine and discuss the association between multidrug resistance 1 gene (MDR1) of gastrointestinal tumors, the expression of P-glycoprotein and resistance to chemotherapeutic drugs. In this study, 126 cases of patients with gastrointestinal tumors admitted to hospital from February 2013 to February 2015 were selected. The expression levels of MDR1 gene were obsreved in the control population and patients before and after treatment by fluoresecent quantitative PCR. The protein expression level of P-glycoprotein was determined using western blotting and enzyme-linked immunosorbent assay. In addition, drug resistance was assessed by ATP-TCA chemosensitivity experiments. The results showed that before treatment, the expression of mRNA in MDR1 of tissues of gastrointestinal tract of the 126 cases was 108-fold larger than that of the gastrointestinal tract of the controls (p<0.05), P-glycoprotein was 87-fold larger than the expression level of the controls (p<0.05). The sensitivity of 126 tumor tissues to different chemotherapeutic drugs was determined, and the results showed that most of the tumor tissues were sensitive to chemotherapeutic drugs, and the sensitivity rate reached 96.4%. Following chemotherapy, the expression of mRNA in MDR1 of tumor tissues and the expression of P-glycoprotein decreased (p<0.05). In conclusion, the MDR1 gene and P-glycoprotein have a positive correlation with the occurrence of gastrointestinal tumors, and a negative correlation between the MDR1 gene and P-glycoprotein with resistance of chemotherapeutic drugs. Therefore, the MDR1 gene and P-glycoprotein can be used as references in the identification and diagnosis of gastrointestinal tumors.

  6. Integrated microsystems for controlled drug delivery.

    PubMed

    Razzacki, S Zafar; Thwar, Prasanna K; Yang, Ming; Ugaz, Victor M; Burns, Mark A

    2004-02-10

    Efficient drug delivery and administration are needed to realize the full potential of molecular therapeutics. Integrated microsystems that incorporate extremely fast sensory and actuation capabilities can fulfill this need for efficient drug delivery tools. Photolithographic technologies borrowed from the semiconductor industry enable mass production of such microsystems. Rapid prototyping allows for the quick development of customized devices that would accommodate for diverse therapeutic requirements. This paper reviews the capabilities of existing microfabrication and their applications in controlled drug delivery microsystems. The next generation of drug delivery systems--fully integrated and self-regulating--would not only improve drug administration, but also revolutionize the health-care industry.

  7. 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.

  8. 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

  9. Ligand-Targeted Drug Delivery.

    PubMed

    Srinivasarao, Madduri; Low, Philip S

    2017-09-12

    Safety and efficacy constitute the major criteria governing regulatory approval of any new drug. The best method to maximize safety and efficacy is to deliver a proven therapeutic agent with a targeting ligand that exhibits little affinity for healthy cells but high affinity for pathologic cells. The probability of regulatory approval can conceivably be further enhanced by exploiting the same targeting ligand, conjugated to an imaging agent, to select patients whose diseased tissues display sufficient targeted receptors for therapeutic efficacy. The focus of this Review is to summarize criteria that must be met during design of ligand-targeted drugs (LTDs) to achieve the required therapeutic potency with minimal toxicity. Because most LTDs are composed of a targeting ligand (e.g., organic molecule, aptamer, protein scaffold, or antibody), spacer, cleavable linker, and therapeutic warhead, criteria for successful design of each component will be described. Moreover, because obstacles to successful drug design can differ among human pathologies, limitations to drug delivery imposed by the unique characteristics of different diseases will be considered. With the explosion of genomic and transcriptomic data providing an ever-expanding selection of disease-specific targets, and with tools for high-throughput chemistry offering an escalating diversity of warheads, opportunities for innovating safe and effective LTDs has never been greater.

  10. Drug-eluting embolic microspheres for local drug delivery - State of the art.

    PubMed

    Fuchs, Katrin; Duran, Rafael; Denys, Alban; Bize, Pierre E; Borchard, Gerrit; Jordan, Olivier

    2017-09-28

    Embolic microspheres or beads used in transarterial chemoembolization are an established treatment method for hepatocellular carcinoma patients. The occlusion of the tumor-feeding vessels by intra-arterial injection of the beads results in tumor necrosis and shrinkage. In this short review, we describe the utility of using these beads as devices for local drug delivery. We review the latest advances in the development of non-biodegradable and biodegradable drug-eluting beads for transarterial chemoembolization. Their capability to load different drugs, such as chemotherapeutics and anti-angiogenic compounds with different physicochemical properties, like charge and hydrophilicity/hydrophobicity, are discussed. We specifically address controlled and sustained drug release from the microspheres, and the resulting in vivo pharmacokinetics in the plasma vs. drug distribution in the targeted tissue. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. 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

  12. Intelligent hydrogels for drug delivery system.

    PubMed

    He, Liumin; Zuo, Qinhua; Xie, Shasha; Huang, Yuexin; Xue, Wei

    2011-09-01

    Intelligent hydrogel, also known as smart hydrogels, are materials with great potential for development in drug delivery system. Intelligent hydrogel also has the ability to perceive as a signal structure change and stimulation. The review introduces the temperature-, pH-, electric signal-, biochemical molecule-, light- and pressure- sensitive hydrogels. Finally, we described the application of intelligent hydrogel in drug delivery system and the recent patents involved for hydrogel in drug delivery.

  13. 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.

  14. Ocular drug delivery system: a reference to natural polymers.

    PubMed

    Pahuja, Priyanka; Arora, Sandeep; Pawar, Pravin

    2012-07-01

    Ocular drug delivery is a very challenging endeavor due to the unique anatomical and physiological barriers. The low ocular bioavailability (<10%) obtained from conventional formulations has forced the scientists to develop new formulations to deliver drugs to ocular tissues at a controlled rate to reduce frequent instillations. The natural polymers have represented the potential to deliver drugs topically through the limited precorneal area and release over a prolonged time period. The important points to be considered during the fabrication of ophthalmic formulations for example, properties of drug molecule and polymer which affect the release rate are discussed. Novel polymers, like arabinogalactan, xyloglucan, gum cordia, locust bean gum, carrageenan and Bletilla striata polysaccharide, besides the conventional polymers like chitosan, starch, sodium alginate, sodium hyaluronate, xanthan gum, gelatin, gellan gum, guar gum, collagen and albumin, have demonstrated the potential to safely deliver drugs at a controlled rate in different ophthalmic formulations. The limitations of topical delivery of genes and chemotherapeutic drugs can be overcome by using natural polymers with characteristic properties. Despite the wide applicability, tremendous efforts are required to establish natural polymers in novel formulations on a commercial scale.

  15. 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.

  16. Magnetic Resonance-Guided Drug Delivery.

    PubMed

    Mikhail, Andrew S; Partanen, Ari; Yarmolenko, Pavel; Venkatesan, Aradhana M; Wood, Bradford J

    2015-11-01

    The use of clinical imaging modalities for the guidance of targeted drug delivery systems, known as image-guided drug delivery (IGDD), has emerged as a promising strategy for enhancing antitumor efficacy. MR imaging is particularly well suited for IGDD applications because of its ability to acquire images and quantitative measurements with high spatiotemporal resolution. The goal of IGDD strategies is to improve treatment outcomes by facilitating planning, real-time guidance, and personalization of pharmacologic interventions. This article reviews basic principles of targeted drug delivery and highlights the current status, emerging applications, and future paradigms of MR-guided drug delivery.

  17. Use of body surface area to calculate chemotherapeutic drug dose in dogs: II. Limitations imposed by pharmacokinetic factors.

    PubMed

    Frazier, D L; Price, G S

    1998-01-01

    Anticancer drug dosages that specify the maximum dose and minimum dosing interval that are tolerated in a population of dogs are commonly recommended. Because the differences between the effective and toxic doses of most cancer chemotherapeutics is slight, it is important to achieve therapeutic concentrations in tumor tissues at the same time that concentrations in nontarget tissues are minimized. In order to determine the dosage regimen that will most likely accomplish these goals, similar drug concentrations must be achieved in all patients dosed according to a specific regimen. Dosing based on body surface area (BSA) is generally used in an effort to normalize drug concentrations. This is because it is well recognized that measures of many physiologic parameters that are responsible for drug disposition, including renal function and energy expenditure, can be normalized by use of BSA. However, there is substantial evidence that drug disposition is not always proportional to BSA. Differences in distribution, metabolism, and excretion pathways may preclude dose extrapolation among species or among individuals within a species based on BSA. Moreover, genetic differences in drug metabolism are well recognized in humans and in laboratory animals, and it is likely that similar differences exist among breeds of dogs. A review of the pharmacokinetic disposition of several cancer chemotherapeutics suggests that studies are needed to determine the most effective method to achieve equivalent anticancer drug concentrations in diverse veterinary patients.

  18. Collagen macromolecular drug delivery systems

    SciTech Connect

    Gilbert, D.L.

    1988-01-01

    The objective of this study was to examine collagen for use as a macromolecular drug delivery system by determining the mechanism of release through a matrix. Collagen membranes varying in porosity, crosslinking density, structure and crosslinker were fabricated. Collagen characterized by infrared spectroscopy and solution viscosity was determined to be pure and native. The collagen membranes were determined to possess native vs. non-native quaternary structure and porous vs. dense aggregate membranes by electron microscopy. Collagen monolithic devices containing a model macromolecule (inulin) were fabricated. In vitro release rates were found to be linear with respect to t{sup {1/2}} and were affected by crosslinking density, crosslinker and structure. The biodegradation of the collagen matrix was also examined. In vivo biocompatibility, degradation and {sup 14}C-inulin release rates were evaluated subcutaneously in rats.

  19. 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

  20. 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.

  1. Optimal stent design for drug delivery.

    PubMed

    Rogers, Campbell D K

    2004-01-01

    The efficacy and safety of drug-eluting coronary stents might differ depending on the pharmacologic agents and stent delivery systems used. Recent research has focused on the various constituents of drug-delivery stents, including the stent backbone, materials used as drug-delivery vehicles, and the physicochemical properties of the pharmacotherapeutic agents themselves. Metal stents coated with an outer layer of polymer (bioabsorbable or non-bioabsorbable) can be drug-loaded, thus providing more controlled and sustained drug delivery and allowing more optimal drug-tissue interactions. Among the next generation of drug-eluting stents will be a stent that uses the non-bioabsorbable polymer phosphorylcholine to release the sirolimus analogue ABT-578; another stent will use a highly deliverable cobalt-chromium metal alloy stent platform and, for the first time, a bioabsorbable polymeric coating (thin-film polylactic acid) for drug encapsulation and release.

  2. Refilling drug delivery depots through the blood.

    PubMed

    Brudno, Yevgeny; Silva, Eduardo A; Kearney, Cathal J; Lewin, Sarah A; Miller, Alex; Martinick, Kathleen D; Aizenberg, Michael; Mooney, David J

    2014-09-02

    Local drug delivery depots have significant clinical utility, but there is currently no noninvasive technique to refill these systems once their payload is exhausted. Inspired by the ability of nanotherapeutics to target specific tissues, we hypothesized that blood-borne drug payloads could be modified to home to and refill hydrogel drug delivery systems. To address this possibility, hydrogels were modified with oligodeoxynucleotides (ODNs) that provide a target for drug payloads in the form of free alginate strands carrying complementary ODNs. Coupling ODNs to alginate strands led to specific binding to complementary-ODN-carrying alginate gels in vitro and to injected gels in vivo. When coupled to a drug payload, sequence-targeted refilling of a delivery depot consisting of intratumor hydrogels completely abrogated tumor growth. These results suggest a new paradigm for nanotherapeutic drug delivery, and this concept is expected to have applications in refilling drug depots in cancer therapy, wound healing, and drug-eluting vascular grafts and stents.

  3. 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

  4. Exploiting EPR in polymer drug conjugate delivery for tumor targeting.

    PubMed

    Modi, Sweta; Prakash Jain, Jay; Domb, A J; Kumar, Neeraj

    2006-01-01

    Treatment of tumor tissue without affecting normal cells has always been formidable task for drug delivery scientists and this task is effectively executed by polymer drug conjugate (PDC) delivery. The novelty of this concept lies in the utilization of a physical mechanism called enhanced permeability and retention (EPR) for targeting tumors. EPR is a physiological phenomenon that is customary for fast growing tumor and solves the problem of targeting the miscreant tissue. PDCs offer added advantages of reduced deleterious effects of anticancer drugs and augmentation of its formulation capability (e.g. Solubility). There are now at least eleven PDCs that have entered phase I/II/III clinical trial as anticancer drugs. PDCs once entered into the tumor tissue, taking advantage of EPR, are endocytosed into the cell either by simple or receptor mediated endocytosis. Various polymeric carriers have been used with hydrolyzable linker arm for conjugation with bioactive moiety. The hydrolyzable linkages of PDC are broken down by acid hydrolyses of lysosomes and releases the drug. High concentrations of the chemotherapeutic agent are maintained near the nucleus, the target site. Passive targeting by PDCs is due to the physiological event of EPR, which is becoming one of the major thrust areas for targeting solid tumors.

  5. 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.

  6. 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

  7. Efficient co-delivery of immiscible hydrophilic/hydrophobic chemotherapeutics by lipid emulsions for improved treatment of cancer.

    PubMed

    Zhang, Bo; Song, Yunmei; Wang, Tianqi; Yang, Shaomei; Zhang, Jing; Liu, Yongjun; Zhang, Na; Garg, Sanjay

    2017-01-01

    Combinational nanomedicine is becoming a topic of much interest in cancer therapy, although its translation into the clinic remains extremely challenging. One of the main obstacles lies in the difficulty to efficiently co-deliver immiscible hydrophilic/hydrophobic drugs into tumor sites. The aim of this study was to develop co-loaded lipid emulsions (LEs) to co-deliver immiscible hydrophilic/hydrophobic drugs to improve cancer therapy and to explore the co-delivery abilities between co-loaded LEs and mixture formulation. Multiple oxaliplatin/irinotecan drug-phospholipid complexes (DPCs) were formulated. Co-loaded LEs were prepared using DPC technique to efficiently encapsulate both drugs. Co-loaded LEs exhibited uniform particle size distribution, desired stability and synchronous release profiles in both drugs. Co-loaded LEs demonstrated superior anti-tumor activity compared with the simple solution mixture and the mixture of single-loaded LEs. Furthermore, co-loaded nanocarriers could co-deliver both drugs into the same cells more efficiently and exhibited the optimized synergistic effect. These results indicate that co-loaded LEs could be a desired formulation for enhanced cancer therapy with potential application prospects. The comparison between co-loaded LEs and mixture formulation is significant for pharmaceutical designs aimed at co-delivery of multiple drugs.

  8. Experiment on the factors for enhancing the susceptibility of cancer cells to chemotherapeutic drug by ultrasound microbubbles.

    PubMed

    Zhao, Ying-Zheng; Gao, Hui-Sheng; Zhou, Zhi-Cai; Tang, Qin-Qin; Lu, Cui-Tao; Jin, Zhuo; Tian, Ji-Lai; Xu, Yan-Yan; Tian, Xin-Qiao; Wang, Lee; Kong, Fan-Lei; Li, Xiao-Kun; Huang, Pin-Tong; He, Hui-Liao; Wu, Yan

    2010-07-01

    The objective of this study was to investigate the factors for enhancing the susceptibility of cancer cells to chemotherapeutic drug by ultrasound microbubbles. Ultrasound (US) combined with phospholipid-based microbubbles (MB) was used to enhance the susceptibility of colon cancer cell line SWD-620 to anticancer drugs Topotecan hydrochloride (TOP). Experiments were designed to investigate the influence of main factors on cell viability and cell inhibition, such as US intensity, MB concentration, drug combination with MB, asynchronous action between US triggered cavitation and drug entering cell, MB particle size. US exposure for 10 sec with US probe power at 0.6 W/cm(2) had satisfied cell viability. Treated with US combined with 15% MB, cell viability maintained more than 85% and cell inhibition 86.16%. Under optimal US combined with MB, TOP showed much higher cell inhibition than that of only TOP group. Cell inhibition under short delayed time (<2 h) for TOP addition did not show obvious difference. In terms of MB particle size, the order of cell inhibition was: Mixture > Micron bubble part > Nanometer bubble part. US combined with MB can enhance the susceptibility of cancer cells to chemotherapeutic drug, which may provide a potential method for US-mediated tumor chemotherapy.

  9. Prodrug Strategies in Ocular Drug Delivery

    PubMed Central

    Barot, Megha; Bagui, Mahuya; Gokulgandhi, Mitan R.; Mitra, Ashim K.

    2015-01-01

    Poor bioavailability of topically instilled drug is the major concern in the field of ocular drug delivery. Efflux transporters, static and dynamic ocular barriers often possess rate limiting factors for ocular drug therapy. Different formulation strategies like suspension, ointment, gels, nanoparticles, implants, dendrimers and liposomes have been employed in order to improve drug permeation and retention by evading rate limiting factors at the site of absorption. Chemical modification such as prodrug targeting various nutrient transporters (amino acids, peptide and vitamin) has evolved a great deal ofintereSt to improve ocular drug delivery. In this review, we have discussed various prodrug strategies which have been widely applied for enhancing therapeutic efficacy of ophthalmic drugs. The purpose of this review is to provide an update on the utilization of prodrug concept in ocular drug delivery. In addition, this review will highlight ongoing academic and industrial research and development in terms of ocular prodrug design and delivery. PMID:22530907

  10. 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.

  11. Microneedles: an emerging transdermal drug delivery system.

    PubMed

    Bariya, Shital H; Gohel, Mukesh C; Mehta, Tejal A; Sharma, Om Prakash

    2012-01-01

    One of the thrust areas in drug delivery research is transdermal drug delivery systems (TDDS) due to their characteristic advantages over oral and parenteral drug delivery systems. Researchers have focused their attention on the use of microneedles to overcome the barrier of the stratum corneum. Microneedles deliver the drug into the epidermis without disruption of nerve endings. Recent advances in the development of microneedles are discussed in this review for the benefit of young scientists and to promote research in the area. Microneedles are fabricated using a microelectromechanical system employing silicon, metals, polymers or polysaccharides. Solid coated microneedles can be used to pierce the superficial skin layer followed by delivery of the drug. Advances in microneedle research led to development of dissolvable/degradable and hollow microneedles to deliver drugs at a higher dose and to engineer drug release. Iontophoresis, sonophoresis and electrophoresis can be used to modify drug delivery when used in concern with hollow microneedles. Microneedles can be used to deliver macromolecules such as insulin, growth hormones, immunobiologicals, proteins and peptides. Microneedles containing 'cosmeceuticals' are currently available to treat acne, pigmentation, scars and wrinkles, as well as for skin tone improvement. Literature survey and patents filled revealed that microneedle-based drug delivery system can be explored as a potential tool for the delivery of a variety of macromolecules that are not effectively delivered by conventional transdermal techniques. © 2011 The Authors. JPP © 2011 Royal Pharmaceutical Society.

  12. [Site-specific drug delivery systems. I. Colon targeted delivery].

    PubMed

    Szente, Virág; Zelkó, Romána

    2007-01-01

    Colon specific drug delivery has gained increased importance not just for the delivery of the drugs for the treatment of local diseases associated with the colon like Chron's disease, ulcerative colitis, irritable bowel syndrome, cancer or infections, but also for the potential it holds for the systemic delivery of proteins (e.g. insulin) and therapeutic peptides. These systems enable the protection of healthy tissues from the side effects of drugs and the drug intake of targeted cells, as well. The formulation of colon specific drug delivery systems is of great impact in the case of diseases having circadian rhythm (midnight gerd). Such circadian rhythm release drug delivery systems are designed to provide a plasma concentration--time profile, which varies according to physiological need at different times during the dosing period, i.e., mimicking the circadian rhythm and severity/manifestation of gastric acid secretion (and/or midnight gerd). In general four primary approaches have been proposed for colon targeted delivery namely pH-dependent systems, time dependent systems, colonic microflora activated systems and prodrugs.

  13. Mechanisms Underlying Drug Delivery to Peripheral Arteries.

    PubMed

    Li, Jun; Tzafriri, Rami; Patel, Sandeep M; Parikh, Sahil A

    2017-04-01

    Delivery of drugs onto arterial targets via endovascular devices commands several principles: dissolution, diffusion, convection, drug binding, barriers to absorption, and interaction between the drug, delivery vehicle, and accepting arterial wall. The understanding of drug delivery in the coronary vasculature is vast; there is ongoing work needed in the peripheral arteries. There are differences that account for some failures of application of coronary technology into the peripheral vascular space. Breakthroughs in peripheral vascular interventional techniques building on current technologies require investigators willing to acknowledge the similarities and differences between these different vascular territories, while developing technologies adapted for peripheral arteries.

  14. Potential applications for halloysite nanotubes based drug delivery systems

    NASA Astrophysics Data System (ADS)

    Sun, Lin

    Drug delivery refers to approaches, formulations, technologies, and systems for transporting a drug in the body. The purpose is to enhance the drug efficacy and to reduce side reactions, which can significantly improve treatment outcomes. Halloysite is a naturally occurred alumino-silicate clay with a tubular structure. It is a biocompatible material with a big surface area which can be used for attachment of targeted molecules. Besides, loaded molecules can present a sustained release manner in solution. These properties make halloysite nanotubes (HNTs) a good option for drug delivery. In this study, a drug delivery system was built based on halloysite via three different fabrication methods: physical adsorption, vacuum loading and layer-by-layer coating. Methotrexate was used as the model drug. Factors that may affect performance in both drug loading and release were tested. Results showed that methotrexate could be incorporated within the HNTs system and released in a sustained manner. Layer-by-layer coating showed a better potential than the other two methods in both MTX loading and release. Besides, lower pH could greatly improve MTX loading and release while the increased number of polyelectrolytes bilayers had a limited impact. Osteosarcoma is the most common primary bone malignancy in children and adolescents. Postoperative recurrence and metastasis has become one of the leading causes for patient death after surgical remove of the tumor mass. A strategy could be a sustained release of chemotherapeutics directly at the primary tumor sites where recurrence would mostly occur. Then, this HNTs based system was tested with osteosarcoma cells in vitro to show the potential of delivering chemotherapeutics in the treatment of osteosarcoma. Methotrexate was incorporated within HNTs with a layer-bylayer coating technique, and drug coated HNTs were filled into nylon-6 which is a common material for surgical sutures in industry. Results showed that (1) methotrexate

  15. 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

  16. 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.

  17. Polysaccharides in colon-specific drug delivery.

    PubMed

    Sinha, V R; Kumria, R

    2001-08-14

    Natural polysaccharides are now extensively used for the development of solid dosage forms for delivery of drug to the colon. The rationale for the development of a polysaccharide based delivery system for colon is the presence of large amounts of polysaccharidases in the human colon as the colon is inhabited by a large number and variety of bacteria which secrete many enzymes e.g. beta-D-glucosidase, beta-D-galactosidase, amylase, pectinase, xylanase, beta-D-xylosidase, dextranase, etc. Various major approaches utilizing polysaccharides for colon-specific delivery are fermentable coating of the drug core, embedding of the drug in biodegradable matrix, formulation of drug-saccharide conjugate (prodrugs). A large number of polysaccharides have already been studied for their potential as colon-specific drug carrier systems, such as chitosan, pectin, chondroitin sulphate, cyclodextrin, dextrans, guar gum, inulin, amylose and locust bean gum. Recent efforts and approaches exploiting these polysaccharides in colon-specific drug delivery are discussed.

  18. Colloidal microgels in drug delivery applications

    PubMed Central

    Vinogradov, Serguei V.

    2005-01-01

    Colloidal microgels have recently received attention as environmentally responsive systems and now are increasingly used in applications as carriers for therapeutic drugs and diagnostic agents. Synthetic microgels consist of a crosslinked polymer network that provides a depot for loaded drugs, protection against environmental hazards and template for post-synthetic modification or vectorization of the drug carriers. The aim of this manuscript is to review recent attempts to develop new microgel formulations for oral drug delivery, to design metal-containing microgels for diagnostic and therapeutic applications, and to advance approaches including the systemic administration of microgels. Novel nanogel drug delivery systems developed in the authors’ laboratory are discussed in details including aspects of their synthesis, vectorization and recent applications for encapsulation of low molecular weight drugs or formulation of biological macromolecules. The findings reviewed here are encouraging for further development of the nanogels as intelligent drug carriers with such features as targeted delivery and triggered drug release. PMID:17168773

  19. Intravenous drug delivery in neonates: lessons learnt.

    PubMed

    Sherwin, Catherine M T; Medlicott, Natalie J; Reith, David M; Broadbent, Roland S

    2014-06-01

    Intravenous drug administration presents a series of challenges that relate to the pathophysiology of the neonate and intravenous infusion systems in neonates. These challenges arise from slow intravenous flow rates, small drug volume, dead space volume and limitations on the flush volume in neonates. While there is a reasonable understanding of newborn pharmacokinetics, an appreciation of the substantial delay and variability in the rate of drug delivery from the intravenous line is often lacking. This can lead to difficulties in accurately determining the pharmacokinetic and pharmacodynamic relationship of drugs in the smallest patients. The physical variables that affect the passage of drugs through neonatal lines need to be further explored in order to improve our understanding of their impact on the delivery of drugs by this route in neonates. Through careful investigation, the underlying causes of delayed drug delivery may be identified and administration protocols can then be modified to ensure predictable, appropriate drug input kinetics.

  20. Recent advances in delivery of drug-nucleic acid combinations for cancer treatment.

    PubMed

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

    2013-12-10

    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.

  1. Nanomedicine and drug delivery: a mini review

    NASA Astrophysics Data System (ADS)

    Mirza, Agha Zeeshan; Siddiqui, Farhan Ahmed

    2014-02-01

    The field of nanotechnology now has pivotal roles in electronics, biology and medicine. Its application can be appraised, as it involves the materials to be designed at atomic and molecular level. Due to the advantage of their size, nanospheres have been shown to be robust drug delivery systems and may be useful for encapsulating drugs and enabling more precise targeting with a controlled release. In this review specifically, we highlight the recent advances of this technology for medicine and drug delivery systems.

  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. Synthetic Lipoproteins as Carriers for Drug Delivery.

    PubMed

    Huang, Gangliang; Liu, Yang; Huang, Hualiang

    2016-01-01

    Synthetic lipoprotein is an effective carrier of targeted delivery for drugs. It has the very small size, good biocompatibility, suitable half-life, and specific lipoprotein receptorbinding capacity. Compared with the traditional natural lipoprotein, synthetic lipoprotein not only retains the original biological characteristics and functions, but also exhibits the excellent characteristics in drug delivery. Herein, the advantages, development, applications, and prospect of synthetic lipoproteins as drug carriers were summarized.

  4. Analysis of high-throughput RNAi screening data in identifying genes mediating sensitivity to chemotherapeutic drugs: statistical approaches and perspectives.

    PubMed

    Ye, Fei; Bauer, Joshua A; Pietenpol, Jennifer A; Shyr, Yu

    2012-01-01

    High-throughput RNA interference (RNAi) screens have been used to find genes that, when silenced, result in sensitivity to certain chemotherapy drugs. Researchers therefore can further identify drug-sensitive targets and novel drug combinations that sensitize cancer cells to chemotherapeutic drugs. Considerable uncertainty exists about the efficiency and accuracy of statistical approaches used for RNAi hit selection in drug sensitivity studies. Researchers require statistical methods suitable for analyzing high-throughput RNAi screening data that will reduce false-positive and false-negative rates. In this study, we carried out a simulation study to evaluate four types of statistical approaches (fold-change/ratio, parametric tests/statistics, sensitivity index, and linear models) with different scenarios of RNAi screenings for drug sensitivity studies. With the simulated datasets, the linear model resulted in significantly lower false-negative and false-positive rates. Based on the results of the simulation study, we then make recommendations of statistical analysis methods for high-throughput RNAi screening data in different scenarios. We assessed promising methods using real data from a loss-of-function RNAi screen to identify hits that modulate paclitaxel sensitivity in breast cancer cells. High-confidence hits with specific inhibitors were further analyzed for their ability to inhibit breast cancer cell growth. Our analysis identified a number of gene targets with inhibitors known to enhance paclitaxel sensitivity, suggesting other genes identified may merit further investigation. RNAi screening can identify druggable targets and novel drug combinations that can sensitize cancer cells to chemotherapeutic drugs. However, applying an inappropriate statistical method or model to the RNAi screening data will result in decreased power to detect the true hits and increase false positive and false negative rates, leading researchers to draw incorrect conclusions. In

  5. 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

  6. Thiolated polymers as mucoadhesive drug delivery systems.

    PubMed

    Duggan, Sarah; Cummins, Wayne; O' Donovan, Orla; Hughes, Helen; Owens, Eleanor

    2017-03-30

    Mucoadhesion is the process of binding a material to the mucosal layer of the body. Utilising both natural and synthetic polymers, mucoadhesive drug delivery is a method of controlled drug release which allows for intimate contact between the polymer and a target tissue. It has the potential to increase bioavailability, decrease potential side effects and offer protection to more sensitive drugs such as proteins and peptide based drugs. The thiolation of polymers has, in the last number of years, come to the fore of mucoadhesive drug delivery, markedly improving mucoadhesion due to the introduction of free thiol groups onto the polymer backbone while also offering a more cohesive polymeric matrix for the slower and more controlled release of drug. This review explores the concept of mucoadhesion and the recent advances in both the polymers and the methods of thiolation used in the synthesis of mucoadhesive drug delivery devices.

  7. 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.

  8. Mucosal drug delivery: membranes, methodologies, and applications.

    PubMed

    Song, Yifan; Wang, Yiping; Thakur, Rashmi; Meidan, Victor M; Michniak, Bozena

    2004-01-01

    In recent years, extensive research into novel forms of drug delivery has suggested that mucosal approaches offer a promising therapeutic alternative, especially for systemically acting drugs. Transmucosal drug delivery offers many benefits, including noninvasive administration, convenience, rapid onset, as well as elimination of hepatic first-pass metabolism. The investigated absorptive surfaces consist of the nasal, buccal, ocular, vaginal, and rectal mucosae. Among these, the nasal and buccal routes have proved the most promising to date. The bioavailability achieved mainly depends upon the pathophysiological state of the mucosa and the properties of both the drug and delivery systems. Various agents can increase the efficacy of transmucosal drug delivery. These include cyclodextrins, bile salts, surfactants, fusidic acid derivatives, microspheres, liposomes, and bioadhesive agents. The mechanisms of action, effectiveness, and toxicity profiles of these enhancers have been investigated extensively in both animal and human models.

  9. 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

  10. Radiation sterilization of new drug delivery systems.

    PubMed

    Abuhanoğlu, Gürhan; Ozer, A Yekta

    2014-06-01

    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.

  11. 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.

  12. Polypeptides and polyaminoacids in drug delivery.

    PubMed

    González-Aramundiz, José Vicente; Lozano, María Victoria; Sousa-Herves, Ana; Fernandez-Megia, Eduardo; Csaba, Noemi

    2012-02-01

    Advances achieved over the last few years in drug delivery have provided novel and versatile possibilities for the treatment of various diseases. Among the biomaterials applied in this field, it is worth highlighting the increasing importance of polyaminoacids and polypeptides. The appealing properties of these polymers are very promising for the design of novel compositions in a variety of drug delivery applications. This review provides an overview on the general characteristics of polyaminoacids and polypeptides and briefly discusses different synthetic pathways for their production. This is followed by a detailed description of different drug delivery applications of these polymers, emphasizing those examples that already reached advanced preclinical development or have entered clinical trials. Polyaminoacids and polypeptides are gaining much attention in drug delivery due to their exceptional properties. Their application as polymers for drug delivery purposes has been sped up by the significant achievements related to their synthesis. Certainly, cancer therapy has benefited the most from these advances, although other fields such as vaccine delivery and alternative administration routes are also being successfully explored. The design of new entities based on polyaminoacids and polypeptides and the improved insight gained in drug delivery guarantee exciting findings in the near future.

  13. 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

  14. Protein-Based Drug-Delivery Materials

    PubMed Central

    Jao, Dave; Xue, Ye; Medina, Jethro; Hu, Xiao

    2017-01-01

    There is a pressing need for long-term, controlled drug release for sustained treatment of chronic or persistent medical conditions and diseases. Guided drug delivery is difficult because therapeutic compounds need to survive numerous transport barriers and binding targets throughout the body. Nanoscale protein-based polymers are increasingly used for drug and vaccine delivery to cross these biological barriers and through blood circulation to their molecular site of action. Protein-based polymers compared to synthetic polymers have the advantages of good biocompatibility, biodegradability, environmental sustainability, cost effectiveness and availability. This review addresses the sources of protein-based polymers, compares the similarity and differences, and highlights characteristic properties and functionality of these protein materials for sustained and controlled drug release. Targeted drug delivery using highly functional multicomponent protein composites to guide active drugs to the site of interest will also be discussed. A systematical elucidation of drug-delivery efficiency in the case of molecular weight, particle size, shape, morphology, and porosity of materials will then be demonstrated to achieve increased drug absorption. Finally, several important biomedical applications of protein-based materials with drug-delivery function—including bone healing, antibiotic release, wound healing, and corneal regeneration, as well as diabetes, neuroinflammation and cancer treatments—are summarized at the end of this review. PMID:28772877

  15. 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

  16. 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

  17. Inner Ear Drug Delivery for Auditory Applications

    PubMed Central

    Swan, Erin E. Leary; Mescher, Mark J.; Sewell, William F.; Tao, Sarah L.; Borenstein, Jeffrey T.

    2008-01-01

    Many inner ear disorders cannot be adequately treated by systemic drug delivery. A blood-cochlear barrier exists, similar physiologically to the blood-brain barrier, which limits the concentration and size of molecules able to leave the circulation and gain access to the cells of the inner ear. However, research in novel therapeutics and delivery systems has led to significant progress in the development of local methods of drug delivery to the inner ear. Intratympanic approaches, which deliver therapeutics to the middle ear, rely on permeation through tissue for access to the structures of the inner ear, whereas intracochlear methods are able to directly insert drugs into the inner ear. Innovative drug delivery systems to treat various inner ear ailments such as ototoxicity, sudden sensorineural hearing loss, autoimmune inner ear disease, and for preserving neurons and regenerating sensory cells are being explored. PMID:18848590

  18. 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

  19. Transpapillary drug delivery to the breast.

    PubMed

    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.

  20. Colloidal polymeric nanoparticles and brain drug delivery.

    PubMed

    Khalil, Najeh Maissar; Mainardes, Rubiana Mara

    2009-07-01

    The blood brain barrier protects the brain from harmful substances in the blood stream and has stopped the development of many powerful and interesting drugs candidates for central nervous system due to the low poor distribution and by efflux mechanisms. Many different approaches have been developed in order to overcome this barrier and the drug gain access to the brain. The polymeric nanoparticles are efficient colloidal systems that have been investigated to the brain drug delivery. This review will focus on the current strategies for brain drug delivery emphasizing the properties and characteristics of polymeric nanoparticles for this purpose.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Use of body surface area (BSA)-based dosages to calculate chemotherapeutic drug dose in dogs: I. Potential problems with current BSA formulae.

    PubMed

    Price, G S; Frazier, D L

    1998-01-01

    The dose of most cancer chemotherapeutic drugs administered to dogs is calculated on the basis of estimated body surface area (BSA); however results of some chemotherapy trials have revealed that this dosing method increases toxicosis in small dogs. The current formula used to estimate BSA in dogs may be inaccurate or the assumption that BSA correlates with chemotherapeutic drug exposure may be unfounded. Results presented in this review suggest that canine BSA estimates may be inaccurate because the values for the constant (K) and exponent (a) in the formulae (BSA = K.Wa) are incorrect or because a linear parameter such as body length is lacking from the formulae. Results that suggest the relationship between BSA and the physiologic/pharmacologic factors that influence drug exposure may not be closely correlated are also presented. Studies are warranted to determine whether there are dosing methods that normalize chemotherapeutic drug toxicity in dogs.

  6. Well-Defined Poly(Ortho Ester Amides) for Potential Drug Carriers: Probing the Effect of Extra- and Intracellular Drug Release on Chemotherapeutic Efficacy.

    PubMed

    Yan, Guoqing; Wang, Jun; Qin, Jiejie; Hu, Liefeng; Zhang, Panpan; Wang, Xin; Tang, Rupei

    2017-03-29

    To compare the chemotherapeutic efficacy determined by extra- and intracellular drug release strategies, poly(ortho ester amide)-based drug carriers (POEAd-C) with well-defined main-chain lengths, are successfully constructed by a facile method. POEAd-C3-doxorubicin (DOX) can be rapidly dissolved to release drug at tumoral extracellular pH (6.5-7.2), while POEAd-C6-DOX can rapidly release drug following gradual swelling at intracellular pH (5.0-6.0). In vitro cytotoxicity shows that POEAd-C3-DOX exhibits more toxic effect on tumor cells than POEAd-C6-DOX at extracellular pH, but POEAd-C6-DOX has stronger tumor penetration and inhibition in vitro and in vivo tumor models. So, POEAd-C6-DOX with the intracellular drug release strategy has stronger overall chemotherapeutic efficacy than POEAd-C3-DOX with extracellular drug release strategy. It is envisioned that these poly(ortho ester amides) can have great potential as drug carriers for efficient chemotherapy with further optimization.

  7. Molecular imprinted polymers as drug delivery vehicles.

    PubMed

    Zaidi, Shabi Abbas

    2016-09-01

    This review is aimed to discuss the molecular imprinted polymer (MIP)-based drug delivery systems (DDS). Molecular imprinted polymers have proved to possess the potential and also as a suitable material in several areas over a long period of time. However, only recently it has been employed for pharmaceuticals and biomedical applications, particularly as drug delivery vehicles due to properties including selective recognition generated from imprinting the desired analyte, favorable in harsh experimental conditions, and feedback-controlled recognitive drug release. Hence, this review will discuss their synthesis, the reason they are selected as drug delivery vehicles and for their applications in several drug administration routes (i.e. transdermal, ocular and gastrointestinal or stimuli-reactive routes).

  8. Learning from biology: synthetic lipoproteins for drug delivery.

    PubMed

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

    2015-01-01

    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 for drugs delivery over their native counterparts while retaining their natural characteristics and biological functions. Their ultra-small size (<30 nm), 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 with 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 approaches employed 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. © 2014 Wiley Periodicals, Inc.

  9. 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

  10. 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.

  11. 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

  12. Designing hydrogels for controlled drug delivery

    NASA Astrophysics Data System (ADS)

    Li, Jianyu; Mooney, David J.

    2016-12-01

    Hydrogel delivery systems can leverage therapeutically beneficial outcomes of drug delivery and have found clinical use. Hydrogels can provide spatial and temporal control over the release of various therapeutic agents, including small-molecule drugs, macromolecular drugs and cells. Owing to their tunable physical properties, controllable degradability and capability to protect labile drugs from degradation, hydrogels serve as a platform on which various physiochemical interactions with the encapsulated drugs occur to control drug release. In this Review, we cover multiscale mechanisms underlying the design of hydrogel drug delivery systems, focusing on physical and chemical properties of the hydrogel network and the hydrogel-drug interactions across the network, mesh and molecular (or atomistic) scales. We discuss how different mechanisms interact and can be integrated to exert fine control in time and space over drug presentation. We also collect experimental release data from the literature, review clinical translation to date of these systems and present quantitative comparisons between different systems to provide guidelines for the rational design of hydrogel delivery systems.

  13. Polymethacrylate microparticles gel for topical drug delivery.

    PubMed

    Labouta, Hagar Ibrahim; El-Khordagui, Labiba K

    2010-10-01

    Evaluating the potentials of particulate delivery systems in topical drug delivery. Polymethacrylate microparticles (MPs) incorporating verapamil hydrochloride (VRP) as a model hydrophilic drug with potential topical clinical uses, using Eudragit RS100 and Eudragit L100 were prepared for the formulation of a composite topical gel. The effect of initial drug loading, polymer composition, particularly the proportion of Eudragit L100 as an interacting polymer component and the HLB of the dispersing agent on MPs characteristics was investigated. A test MPs formulation was incorporated in gel and evaluated for drug release and human skin permeation. MPs showed high % incorporation efficiency and % yield. Composition of the hybrid polymer matrix was a main determinant of MPs characteristics, particularly drug release. Factors known to influence drug release such as MPs size and high drug solubility were outweighed by strong VRP-Eudragit L100 interaction. The developed MPs gel showed controlled VRP release and reduced skin retention compared to a free drug gel. Topical drug delivery and skin retention could be modulated using particulate delivery systems. From a practical standpoint, the VRP gel developed may offer advantage in a range of dermatological conditions, in response to the growing off-label topical use of VRP.

  14. 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

  15. Hydrogen peroxide mediated transvaginal drug delivery.

    PubMed

    Fatakdawala, Hussain; Uhland, Scott A

    2011-05-16

    Simple, safe and effective permeability enhancers are crucial for successful non-invasive drug delivery methods. We seek local permeability augmentation mechanisms for integration into passive or active architectures in order to enable novel therapeutic delivery routes of the target drug while minimizing drug formulation challenges. This study explores the efficacy of hydrogen peroxide (HP) as a permeability enhancer for transmucosal delivery of macromolecules. HP at low concentrations (2–8 mM) is an effective permeability enhancer that is locally metabolized and safe. HP improves drug permeation through mucosa by altering tight junctions (TJ) between cells and oxidizing enzymes that function to degrade the foreign species. Results from trans-epithelial electrical resistance measurements and cell viability assay show reversible disassembly of TJ with minimal cell damage demonstrating the feasibility of HP as a safe permeability enhancer for drug delivery. Permeation studies show that HP treatment of cell cultured vaginal mucosa significantly enhances the permeability to insulin by more than an order of magnitude. This work lays foundation for the development of a drug delivery platform that administers drug doses by enhancing the permeability of local epithelial tissue via a separate HP treatment step.

  16. 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

  17. 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

  18. 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.

  19. Tumor Penetrating Theranostic Nanoparticles for Enhancement of Targeted and Image-guided Drug Delivery into Peritoneal Tumors following Intraperitoneal Delivery.

    PubMed

    Gao, Ning; Bozeman, Erica N; Qian, Weiping; Wang, Liya; Chen, Hongyu; Lipowska, Malgorzata; Staley, Charles A; Wang, Y Andrew; Mao, Hui; Yang, Lily

    2017-01-01

    The major obstacles in intraperitoneal (i.p.) chemotherapy of peritoneal tumors are fast absorption of drugs into the blood circulation, local and systemic toxicities, inadequate drug penetration into large tumors, and drug resistance. Targeted theranostic nanoparticles offer an opportunity to enhance the efficacy of i.p. therapy by increasing intratumoral drug delivery to overcome resistance, mediating image-guided drug delivery, and reducing systemic toxicity. Herein we report that i.p. delivery of urokinase plasminogen activator receptor (uPAR) targeted magnetic iron oxide nanoparticles (IONPs) led to intratumoral accumulation of 17% of total injected nanoparticles in an orthotopic mouse pancreatic cancer model, which was three-fold higher compared with intravenous delivery. Targeted delivery of near infrared dye labeled IONPs into orthotopic tumors could be detected by non-invasive optical and magnetic resonance imaging. Histological analysis revealed that a high level of uPAR targeted, PEGylated IONPs efficiently penetrated into both the peripheral and central tumor areas in the primary tumor as well as peritoneal metastatic tumor. Improved theranostic IONP delivery into the tumor center was not mediated by nonspecific macrophage uptake and was independent from tumor blood vessel locations. Importantly, i.p. delivery of uPAR targeted theranostic IONPs carrying chemotherapeutics, cisplatin or doxorubicin, significantly inhibited the growth of pancreatic tumors without apparent systemic toxicity. The levels of proliferating tumor cells and tumor vessels in tumors treated with the above theranostic IONPs were also markedly decreased. The detection of strong optical signals in residual tumors following i.p. therapy suggested the feasibility of image-guided surgery to remove drug-resistant tumors. Therefore, our results support the translational development of i.p. delivery of uPAR-targeted theranostic IONPs for image-guided treatment of peritoneal tumors.

  20. Tumor Penetrating Theranostic Nanoparticles for Enhancement of Targeted and Image-guided Drug Delivery into Peritoneal Tumors following Intraperitoneal Delivery

    PubMed Central

    Gao, Ning; Bozeman, Erica N.; Qian, Weiping; Wang, Liya; Chen, Hongyu; Lipowska, Malgorzata; Staley, Charles A; Wang, Y. Andrew; Mao, Hui; Yang, Lily

    2017-01-01

    The major obstacles in intraperitoneal (i.p.) chemotherapy of peritoneal tumors are fast absorption of drugs into the blood circulation, local and systemic toxicities, inadequate drug penetration into large tumors, and drug resistance. Targeted theranostic nanoparticles offer an opportunity to enhance the efficacy of i.p. therapy by increasing intratumoral drug delivery to overcome resistance, mediating image-guided drug delivery, and reducing systemic toxicity. Herein we report that i.p. delivery of urokinase plasminogen activator receptor (uPAR) targeted magnetic iron oxide nanoparticles (IONPs) led to intratumoral accumulation of 17% of total injected nanoparticles in an orthotopic mouse pancreatic cancer model, which was three-fold higher compared with intravenous delivery. Targeted delivery of near infrared dye labeled IONPs into orthotopic tumors could be detected by non-invasive optical and magnetic resonance imaging. Histological analysis revealed that a high level of uPAR targeted, PEGylated IONPs efficiently penetrated into both the peripheral and central tumor areas in the primary tumor as well as peritoneal metastatic tumor. Improved theranostic IONP delivery into the tumor center was not mediated by nonspecific macrophage uptake and was independent from tumor blood vessel locations. Importantly, i.p. delivery of uPAR targeted theranostic IONPs carrying chemotherapeutics, cisplatin or doxorubicin, significantly inhibited the growth of pancreatic tumors without apparent systemic toxicity. The levels of proliferating tumor cells and tumor vessels in tumors treated with the above theranostic IONPs were also markedly decreased. The detection of strong optical signals in residual tumors following i.p. therapy suggested the feasibility of image-guided surgery to remove drug-resistant tumors. Therefore, our results support the translational development of i.p. delivery of uPAR-targeted theranostic IONPs for image-guided treatment of peritoneal tumors. PMID

  1. Novel biodegradable nanocarriers for enhanced drug delivery.

    PubMed

    Gagliardi, Mariacristina

    2016-12-01

    With the refinement of functional properties, the interest around biodegradable materials, in biorelated applications and, in particular, in their use as controlled drug-delivery systems, increased in the last decades. Biodegradable materials are an ideal platform to obtain nanoparticles for spatiotemporal controlled drug delivery for the in vivo administration, thanks to their biocompatibility, functionalizability, the control exerted on delivery rates and the complete degradation. Their application in systems for cancer treatment, brain and cardiovascular diseases is already a consolidated practice in research, while the bench-to-bedside translation is still late. This review aims at summarizing reported applications of biodegradable materials to obtain drug-delivery nanoparticles in the last few years, giving a complete overview of pros and cons related to degradable nanomedicaments.

  2. Intelligent, self-powered, drug delivery systems.

    PubMed

    Patra, Debabrata; Sengupta, Samudra; Duan, Wentao; Zhang, Hua; Pavlick, Ryan; Sen, Ayusman

    2013-02-21

    Self-propelled nano/micromotors and pumps are considered to be next generation drug delivery systems since the carriers can either propel themselves ("motor"-based drug delivery) or be delivered ("pump"-based drug delivery) to the target in response to specific biomarkers. Recently, there has been significant advancement towards developing nano/microtransporters into proof-of-concept tools for biomedical applications. This review encompasses the progress made to date on the design of synthetic nano/micromotors and pumps with respect to transportation and delivery of cargo at specific locations. Looking ahead, it is possible to imagine a day when intelligent machines navigate through the human body and perform challenging tasks.

  3. 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

  4. Brain Mitochondrial Drug Delivery: Influence of Drug Physicochemical Properties

    PubMed Central

    Durazo, Shelley A.; Kadam, Rajendra S.; Drechsel, Derek; Patel, Manisha

    2017-01-01

    Purpose To determine the influence of drug physicochemical properties on brain mitochondrial delivery of 20 drugs at physiological pH. Methods The delivery of 8 cationic drugs (beta-blockers), 6 neutral drugs (corticosteroids), and 6 anionic drugs (non-steroidal anti-inflammatory drugs, NSAIDs) to isolated rat brain mitochondria was determined with and without membrane depolarization. Multiple linear regression was used to determine whether lipophilicity (Log D), charge, polarizability, polar surface area (PSA), and molecular weight influence mitochondrial delivery. Results The Log D for beta-blockers, corticosteroids, and NSAIDs was in the range of −1.41 to 1.37, 0.72 to 2.97, and −0.98 to 2, respectively. The % mitochondrial uptake increased exponentially with an increase in Log D for each class of drugs, with the uptake at a given lipophilicity obeying the rank order cationic>anionic>neutral. Valinomycin reduced membrane potential and the delivery of positively charged propranolol and betaxolol. The best equation for the combined data set was Log % Uptake=0.333 Log D+ 0.157 Charge – 0.887 Log PSA+2.032 (R2=0.738). Conclusions Drug lipopohilicity, charge, and polar surface area and membrane potential influence mitochondrial drug delivery, with the uptake of positively charged, lipophilic molecules being the most efficient. PMID:21796482

  5. Brain mitochondrial drug delivery: influence of drug physicochemical properties.

    PubMed

    Durazo, Shelley A; Kadam, Rajendra S; Drechsel, Derek; Patel, Manisha; Kompella, Uday B

    2011-11-01

    To determine the influence of drug physicochemical properties on brain mitochondrial delivery of 20 drugs at physiological pH. The delivery of 8 cationic drugs (beta-blockers), 6 neutral drugs (corticosteroids), and 6 anionic drugs (non-steroidal anti-inflammatory drugs, NSAIDs) to isolated rat brain mitochondria was determined with and without membrane depolarization. Multiple linear regression was used to determine whether lipophilicity (Log D), charge, polarizability, polar surface area (PSA), and molecular weight influence mitochondrial delivery. The Log D for beta-blockers, corticosteroids, and NSAIDs was in the range of -1.41 to 1.37, 0.72 to 2.97, and -0.98 to 2, respectively. The % mitochondrial uptake increased exponentially with an increase in Log D for each class of drugs, with the uptake at a given lipophilicity obeying the rank order cationic>anionic>neutral. Valinomycin reduced membrane potential and the delivery of positively charged propranolol and betaxolol. The best equation for the combined data set was Log % Uptake = 0.333 Log D + 0.157 Charge - 0.887 Log PSA + 2.032 (R(2) = 0.738). Drug lipopohilicity, charge, and polar surface area and membrane potential influence mitochondrial drug delivery, with the uptake of positively charged, lipophilic molecules being the most efficient.

  6. 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

  7. 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.

  8. Cellulose based polymeric systems in drug delivery

    USDA-ARS?s Scientific Manuscript database

    The pharmaceutical industry requires the development of biodegradable, biocompatible, non toxic, site specific drug delivery polymers, which can be easily coupled with drugs to be delivered orally, topically, locally, or parenterally. The use of the most abundant biopolymer, cellulose along with its...

  9. A Partnership Training Program: Studying Targeted Drug Delivery Using Nanoparticles In Breast Cancer Diagnosis and Therapy

    DTIC Science & Technology

    2015-12-01

    labeled with dye AF680 and the cell nuclei were stained with DAPI. The drug-delivery efficiency of scfbDb was also demonstrated with anti-tumor...effects of the targeted delivery, anti-angiogenics and chemotherapeutics in breast cancer animal models. Histological staining will be used to study the...was 200 mg/mL) for 24 h. Excess micelles were removed by washing three times with PBS, then cells were stained with 200 mL DAPI (20 mg/mL) for 1 min

  10. 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

  11. 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.

  12. Nanotech approaches to drug delivery and imaging.

    PubMed

    Sahoo, Sanjeeb K; Labhasetwar, Vinod

    2003-12-15

    Nanotechnology, a multidisciplinary scientific undertaking, involves creation and utilization of materials, devices or systems on the nanometer scale. The field of nanotechnology is currently undergoing explosive development on many fronts. The technology is expected to create innovations and play a critical role in various biomedical applications, not only in drug delivery, but also in molecular imaging, biomarkers and biosensors. Target-specific drug therapy and methods for early diagnosis of pathologies are the priority research areas where nanotechnology would play a vital role. This review considers different nanotechnology-based drug delivery and imaging approaches, and their economic impact on pharmaceutical and biomedical industries.

  13. 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

  14. 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.

  15. 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.

  16. Multicomponent high-performance liquid chromatography/tandem mass spectrometry analysis of ten chemotherapeutic drugs in wipe samples.

    PubMed

    Maeda, Shinichiro; Miwa, Yoshihiro

    2013-03-15

    Progress in chemotherapy leads to increased numbers and variety of chemotherapeutic drugs, and multicomponent analysis of these drugs is a necessary step. We used liquid chromatography-tandem mass spectrometry and developed a multicomponent analysis of ten drugs used in chemotherapy: vindesine, vincristine, vinblastine, doxorubicin, epirubicin, ifosfamide, cyclophosphamide, irinotecan, docetaxel, and paclitaxel. We selected five internal standards for each category of drug, because the ionization efficiencies of product ions varied widely. The total run time was 22min, applying a gradient elution of water and acetonitrile in the presence of 0.1% formic acid. The lower limit of quantification was 50ng/wipe samples for vindesine, vincristine, and vinblastine, and 5ng/wipe samples for the remaining seven drugs. Accuracy (88.6-112.9%, 85.2-111.7%) and precision (1.0-11.5%CV, 3.6-14.4%CV) in within-run and between-run assays of QC solutions were acceptable. Without outliers, in within-run and between-run assays of QC samples, accuracy was 90.6-113.9% and 91.1-130.4%, respectively, and precision was 2.2-19.0%CV and 4.8-14.9%CV, respectively. Accuracy and precision of High QC samples of irinotecan were deviated. Our analysis procedure has sufficient sensitivity and is convenient enough for regular monitoring.

  17. Emulsion forming drug delivery system for lipophilic drugs.

    PubMed

    Wadhwa, Jyoti; Nair, Anroop; Kumria, Rachna

    2012-01-01

    In the recent years, there is a growing interest in the lipid-based formulations for delivery of lipophilic drugs. Due to their potential as therapeutic agents, preferably these lipid soluble drugs are incorporated into inert lipid carriers such as oils, surfactant dispersions, emulsions, liposomes etc. Among them, emulsion forming drug delivery systems appear to be a unique and industrially feasible approach to overcome the problem of low oral bioavailability associated with the BCS class II drugs. Self-emulsifying formulations are ideally isotropic mixtures of oils, surfactants and co-solvents that emulsify to form fine oil in water emulsions when introduced in aqueous media. Fine oil droplets would pass rapidly from stomach and promote wide distribution of drug throughout the GI tract, thereby overcome the slow dissolution step typically observed with solid dosage forms. Recent advances in drug carrier technologies have promulgated the development of novel drug carriers such as control release self-emulsifying pellets, microspheres, tablets, capsules etc. that have boosted the use of "self-emulsification" in drug delivery. This article reviews the different types of formulations and excipients used in emulsion forming drug delivery system to enhance the bioavailability of lipophilic drugs.

  18. Classification of stimuli-responsive polymers as anticancer drug delivery systems.

    PubMed

    Taghizadeh, Bita; Taranejoo, Shahrouz; Monemian, Seyed Ali; Salehi Moghaddam, Zoha; Daliri, Karim; Derakhshankhah, Hossein; Derakhshani, Zaynab

    2015-02-01

    Although several anticancer drugs have been introduced as chemotherapeutic agents, the effective treatment of cancer remains a challenge. Major limitations in the application of anticancer drugs include their nonspecificity, wide biodistribution, short half-life, low concentration in tumor tissue and systemic toxicity. Drug delivery to the tumor site has become feasible in recent years, and recent advances in the development of new drug delivery systems for controlled drug release in tumor tissues with reduced side effects show great promise. In this field, the use of biodegradable polymers as drug carriers has attracted the most attention. However, drug release is still difficult to control even when a polymeric drug carrier is used. The design of pharmaceutical polymers that respond to external stimuli (known as stimuli-responsive polymers) such as temperature, pH, electric or magnetic field, enzymes, ultrasound waves, etc. appears to be a successful approach. In these systems, drug release is triggered by different stimuli. The purpose of this review is to summarize different types of polymeric drug carriers and stimuli, in addition to the combination use of stimuli in order to achieve a better controlled drug release, and it discusses their potential strengths and applications. A survey of the recent literature on various stimuli-responsive drug delivery systems is also provided and perspectives on possible future developments in controlled drug release at tumor site have been discussed.

  19. Drug Delivery Research: The Invention Cycle.

    PubMed

    Park, Kinam

    2016-07-05

    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.

  20. Characterization of particulate drug delivery systems for oral delivery of Peptide and protein drugs.

    PubMed

    Christophersen, Philip Carsten; Fano, Mathias; Saaby, Lasse; Yang, Mingshi; Nielsen, Hanne Mørck; Mu, Huiling

    2015-01-01

    Oral drug delivery is a preferred route because of good patient compliance. However, most peptide/ protein drugs are delivered via parenteral routes because of the absorption barriers in the gastrointestinal (GI) tract such as enzymatic degradation by proteases and low permeability acrossthe biological membranes. To overcome these barriers, different formulation strategies for oral delivery of biomacromolecules have been proposed, including lipid based formulations and polymer-based particulate drug delivery systems (DDS). The aim of this review is to summarize the existing knowledge about oral delivery of peptide/protein drugs and to provide an overview of formulationand characterization strategies. For a better understanding of the challenges in oral delivery of peptide/protein drugs, the composition of GI fluids and the digestion processes of different kinds of excipients in the GI tract are summarized. Additionally, the paper provides an overview of recent studies on characterization of solid drug carriers for peptide/protein drugs, drug distribution in particles, drug release and stability in simulated GI fluids, as well as the absorption of peptide/protein drugs in cell-based models. The use of biorelevant media when applicable can increase the knowledge about the quality of DDS for oral protein delivery. Hopefully, the knowledge provided in this review will aid the establishment of improved biorelevant models capable of forecasting the performance of particulate DDS for oral peptide/protein delivery.

  1. Drug delivery systems for brain tumor therapy.

    PubMed

    Rautioa, Jarkko; Chikhale, Prashant J

    2004-01-01

    Brain tumors are one of the most lethal forms of cancer. They are extremely difficult to treat. Although, the rate of brain tumor incidence is relatively low, the field clearly lacks therapeutic strategies capable of overcoming barriers for effective delivery of drugs to brain tumors. Clinical failure of many potentially effective therapeutics for the treatment of brain tumors is usually not due to a lack of drug potency, but rather can be attributed to shortcomings in the methods by which a drug is delivered to the brain and into brain tumors. In response to the lack of efficacy of conventional drug delivery methods, extensive efforts have been made to develop novel strategies to overcome the obstacles for brain tumor drug delivery. The challenge is to design therapeutic strategies that deliver drugs to brain tumors in a safe and effective manner. This review provides some insight into several potential techniques that have been developed to improve drug delivery to brain tumors, and it should be helpful to clinicians and research scientists as well.

  2. 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.

  3. Nanoparticles and microparticles for skin drug delivery.

    PubMed

    Prow, Tarl W; Grice, Jeffrey E; Lin, Lynlee L; Faye, Rokhaya; Butler, Margaret; Becker, Wolfgang; Wurm, Elisabeth M T; Yoong, Corinne; Robertson, Thomas A; Soyer, H Peter; Roberts, Michael S

    2011-05-30

    Skin is a widely used route of delivery for local and systemic drugs and is potentially a route for their delivery as nanoparticles. The skin provides a natural physical barrier against particle penetration, but there are opportunities to deliver therapeutic nanoparticles, especially in diseased skin and to the openings of hair follicles. Whilst nanoparticle drug delivery has been touted as an enabling technology, its potential in treating local skin and systemic diseases has yet to be realised. Most drug delivery particle technologies are based on lipid carriers, i.e. solid lipid nanoparticles and nanoemulsions of around 300 nm in diameter, which are now considered microparticles. Metal nanoparticles are now recognized for seemingly small drug-like characteristics, i.e. antimicrobial activity and skin cancer prevention. We present our unpublished clinical data on nanoparticle penetration and previously published reports that support the hypothesis that nanoparticles >10nm in diameter are unlikely to penetrate through the stratum corneum into viable human skin but will accumulate in the hair follicle openings, especially after massage. However, significant uptake does occur after damage and in certain diseased skin. Current chemistry limits both atom by atom construction of complex particulates and delineating their molecular interactions within biological systems. In this review we discuss the skin as a nanoparticle barrier, recent work in the field of nanoparticle drug delivery to the skin, and future directions currently being explored. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Lung surfactant as a drug delivery system.

    PubMed

    Vermehren, C; Frokjaer, S; Aurstad, T; Hansen, J

    2006-01-03

    Lung surfactant is a complex mixture of mainly phospholipids and proteins. The composition leads to a unique spreading effect of the surfactant as well as spontaneous vesicle formation, which may be favourable characteristics of a drug delivery system for pulmonary delivery. The aim of study was to investigate the potential use of the surfactant extract, HL10 (LeoPharma, DK) as a drug delivery system. Studies involved incorporation of hydrophilic- and amphipathic model drugs (sucrose and acylated peptides) into HL10 and elucidation of the influence of surfactant proteins on the HL10 behaviour. Results showed that HL10 vesicles did not retain sucrose indicating formation of leaky vesicles. Studying the influence of surfactant proteins on release from DPPC-liposomes showed tendencies toward a protein-induced release. Hence, the surfactant proteins may influence the membrane lipid packing and characteristics resulting in leakiness of the membranes. Incorporation of acylated peptides into HL10 depended on the chain length rendering a successful incorporation of the peptide acylated with C14-acyl chains. This study suggests that HL10 may be a promising drug delivery system for the pulmonary delivery of amphipathic drug substances, e.g. therapeutically active acylated peptides (e.g. acylated insulin).

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

    PubMed Central

    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

    2016-01-01

    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

  6. 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

  7. 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

  8. Functional Cyclodextrin Polyrotaxanes for Drug Delivery

    NASA Astrophysics Data System (ADS)

    Yui, Nobuhiko; Katoono, Ryo; Yamashita, Atsushi

    The mobility of cyclodextrins (CDs) threaded onto a linear polymeric chain and the dethreading of the CDs from the chain are the most fascinating features seen in polyrotaxanes. These structural characteristics are very promising for their possible applications in drug delivery. Enhanced multivalent interaction between ligand-receptor systems by using ligand-conjugated polyrotaxanes would be just one of the excellent properties related to the CD mobility. Gene delivery using cytocleavable polyrotaxanes is a more practical but highly crucial issue in drug delivery. Complexation of the polyrotaxanes with DNA and its intracellular DNA release ingeniously utilizes both CD mobility and polyrotaxane dissociation to achieve effective gene delivery. Such a supramolecular approach using CD-containing polyrotaxanes is expected to exploit a new paradigm of biomaterials.

  9. The interaction of the chemotherapeutic drug chlorambucil with human glutathione transferase A1-1: kinetic and structural analysis.

    PubMed

    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.

  10. 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

  11. Mechanisms of resistance to chemotherapeutic and anti-angiogenic drugs as novel targets for pancreatic cancer therapy

    PubMed Central

    Tamburrino, Anna; Piro, Geny; Carbone, Carmine; Tortora, Giampaolo; Melisi, Davide

    2013-01-01

    Pancreatic cancer remains one of the most lethal and poorly understood human malignancies and will continue to be a major unsolved health problem in the 21st century. Despite efforts over the past three decades to improve diagnosis and treatment, the prognosis for patients with pancreatic cancer is extremely poor with or without treatment, and incidence rates are virtually identical to mortality rates. Although advances have been made through the identification of relevant molecular pathways in pancreatic cancer, there is still a critical, unmet need for the translation of these findings into effective therapeutic strategies that could reduce the intrinsic drug resistance of this disease and for the integration of these molecularly targeted agents into established combination chemotherapy and radiotherapy regimens in order to improve patients’ survival. Tumors are heterogeneous cellular entities whose growth and progression depend on reciprocal interactions between genetically altered neoplastic cells and a non-neoplastic microenvironment. To date, most of the mechanisms of resistance studied have been related to tumor cell-autonomous signaling pathways. However, recent data suggest a putative important role of tumor microenvironment in the development and maintenance of resistance to classic chemotherapeutic and targeted therapies. This present review is meant to describe and discuss some of the most important advances in the comprehension of the tumor cell-autonomous and tumor microenvironment-related molecular mechanisms responsible for the resistance of pancreatic cancer to the proapoptotic activity of the classic chemotherapeutic agents and to the most novel anti-angiogenic drugs. We present some of the emerging therapeutic targets for the modulation of this resistant phenotype. PMID:23641216

  12. 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

  13. Nanoparticles and nanofibers for topical drug delivery

    PubMed Central

    Goyal, Ritu; Macri, Lauren K.; Kaplan, Hilton M.; Kohn, Joachim

    2016-01-01

    This review provides the first comprehensive overview of the use of both nanoparticles and nanofibers for topical drug delivery. Researchers have explored the use of nanotechnology, specifically nanoparticles and nanofibers, as drug delivery systems for topical and transdermal applications. This approach employs increased drug concentration in the carrier, in order to increase drug flux into and through the skin. Both nanoparticles and nanofibers can be used to deliver hydrophobic and hydrophilic drugs and are capable of controlled release for a prolonged period of time. The examples presented provide significant evidence that this area of research has—and will continue to have — a profound impact on both clinical outcomes and the development of new products. PMID:26518723

  14. 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

  15. 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

  16. 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.

  17. 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

  18. Collagen-coated microparticles in drug delivery.

    PubMed

    Sehgal, Praveen Kumar; Srinivasan, Aishwarya

    2009-07-01

    Advantages of drug-incorporated collagen particles have been described for the controlled delivery system for therapeutic actions. The attractiveness of collagen lies in its low immunogenicity and high biocompatibility. It is also recognized by the body as a natural constituent rather than a foreign body. Our research and development efforts are focused towards addressing some of the limitations of collagen, like the high viscosity of an aqueous phase, nondissolution in neutral pH buffers, thermal instability (denaturation) and biodegradability, to make it an ideal material for drug delivery with particular reference to microparticles. These limitations could be overcome by making collagen conjugates with other biomaterials or chemically modifying collagen monomer without affecting its triple helical conformation and maintaining its native properties. This article highlights collagen microparticles' present status as a carrier in drug delivery.

  19. Ultrasound-mediated gastrointestinal drug delivery.

    PubMed

    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

    2015-10-21

    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.

  20. 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

  1. The potentials of nanotechnology-based drug delivery system for treatment of ovarian cancer.

    PubMed

    Gidwani, Bina; Vyas, Amber

    2015-01-01

    Ovarian cancer is one of the leading causes for death of women. Every year the percentage of mortality rate is increasing day by day. Various chemotherapeutic agents are used to increase the survival rate of patients with ovarian cancer, but the available conventional dosage forms/marketed preparations are associated with several limitations. The use of nanotechnology in drug delivery contributes to their small size (10-100 nm), which improves the circulation and enables superior accumulation of therapeutic drugs at the tumor sites. In future, the use of nanotechnology will enable passive targeting and further improvements can be made using targeting moieties.

  2. Local Drug Delivery to Prevent Restenosis

    PubMed Central

    Seedial, Stephen M.; Ghosh, Soumojit; Saunders, R. Scott; Suwanabol, Pasithorn A.; Shi, Xudong; Liu, Bo; Kent, K. Craig

    2013-01-01

    Introduction Despite significant advances in vascular biology, bioengineering and pharmacology, restenosis remains a limitation to the overall efficacy of vascular reconstructions, both percutaneous and open. Although the pathophysiology of intimal hyperplasia is complex, a number of drugs and/or molecular tools have been identified that can prevent restenosis. Moreover, the focal nature of this process lends itself to treatment with local drug administration. In this article we provide a broad overview of current and future techniques for local drug delivery that have been developed to prevent restenosis following vascular intervention. Methods A systematic electronic literature search using PubMed was performed for all accessible published articles through September 2012. In an effort to remain current, additional searches were performed for abstracts presented at relevant societal meetings, filed patents, clinical trials and funded NIH awards. Results The efficacy of local drug delivery has been demonstrated in the coronary circulation with the current clinical use of drug-eluting stents (DES). Until recently, however, DES were not found to be efficacious in the peripheral circulation. Further pursuit of intraluminal devices has led to the development of balloon-based technologies with a recent surge in trials involving drug-eluting balloons. Early data appears encouraging, particularly for treatment of lesions in the superficial femoral artery, with several devices having recently received the CE mark in Europe. Investigators have also explored periadventitial application of biomaterials containing anti-restenotic drugs, an approach that could be particularly useful for surgical bypass or endarterectomy. In the past systemic drug delivery has been unsuccessful, however, there has been recent exploration of intravenous delivery of drugs designed specifically to target injured or reconstructed arteries. Our review revealed a multitude of additional interesting

  3. Light induced drug delivery into cancer cells.

    PubMed

    Shamay, Yosi; Adar, Lily; Ashkenasy, Gonen; David, Ayelet

    2011-02-01

    Cell-penetrating peptides (CPPs) can be used for intracellular delivery of a broad variety of cargoes, including various nanoparticulate pharmaceutical carriers. However, the cationic nature of all CPP sequences, and thus lack of cell specificity, limits their in vivo use for drug delivery applications. Here, we have devised and tested a strategy for site-specific delivery of dyes and drugs into cancer cells by using polymers bearing a light activated caged CPP (cCPP). The positive charge of Lys residues on the minimum sequence of the CPP penetratin ((52)RRMKWKK(58)) was masked with photo-cleavable groups to minimize non-specific adsorption and cellular uptake. Once illuminated by UV light, these protecting groups were cleaved, the positively charged CPP regained its activity and facilitated rapid intracellular delivery of the polymer-dye or polymer-drug conjugates into cancer cells. We have found that a 10-min light illumination time was sufficient to enhance the penetration of the polymer-CPP conjugates bearing the proapoptotic peptide, (D)(KLAKLAK)(2), into 80% of the target cells, and to promote a 'switch' like cytotoxic activity resulting a shift from 100% to 10% in cell viability after 2 h. This report provides an example for tumor targeting by means of light activation of cell-penetrating peptides for intracellular drug delivery.

  4. Cancer nanomedicine: from drug delivery to imaging.

    PubMed

    Chow, Edward Kai-Hua; Ho, Dean

    2013-12-18

    Nanotechnology-based chemotherapeutics and imaging agents represent a new era of "cancer nanomedicine" working to deliver versatile payloads with favorable pharmacokinetics and capitalize on molecular and cellular targeting for enhanced specificity, efficacy, and safety. Despite the versatility of many nanomedicine-based platforms, translating new drug or imaging agents to the clinic is costly and often hampered by regulatory hurdles. Therefore, translating cancer nanomedicine may largely be application-defined, where materials are adapted only toward specific indications where their properties confer unique advantages. This strategy may also realize therapies that can optimize clinical impact through combinatorial nanomedicine. In this review, we discuss how particular materials lend themselves to specific applications, the progress to date in clinical translation of nanomedicine, and promising approaches that may catalyze clinical acceptance of nano.

  5. 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.

  6. 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

  7. Shenmai injection enhances the cytotoxicity of chemotherapeutic drugs against colorectal cancers via improving their subcellular distribution.

    PubMed

    Liu, Wen-Yue; Zhang, Jing-Wei; Yao, Xue-Quan; Jiang, Chao; He, Ji-Chao; Ni, Pin; Liu, Jia-Li; Chen, Qian-Ying; Li, Qing-Ran; Zang, Xiao-Jie; Yao, Lan; Liu, Ya-Zhong; Wang, Mu-Lan; Shen, Pei-Qiang; Wang, Guang-Ji; Zhou, Fang

    2017-02-01

    Shenmai injection (SMI) is a Chinese patent-protected injection, which was mainly made of Red Ginseng and Radix Ophiopogonis and widely used for treating coronary heart disease and tumors by boosting Qi and nourishing Yin. In this study we examined whether SMI could produce direct synergetic effects on the cytoxicity of adriamycin (ADR) and paclitaxel (PTX) in colorectal cancers in vivo and in vitro, and explored the underlying pharmacokinetic mechanisms. BALB/c nude mice with LoVo colon cancer xenografts were intraperitoneally injected with ADR (2 mg·kg(-1)·3d(-1)) or PTX (7.5 mg·kg(-1)·3d(-1)) with or without SMI (0.01 mL·g(-1)·d(-1)) for 13 d. Co-administration of SMI significantly enhanced the chemotherapeutic efficacy of ADR and PTX, whereas administration of SMI alone at the given dosage did not produce visible anti-cancer effects, The chemosensitizing action of SMI was associated with increased concentrations of ADR and PTX in the plasma and tumors. In Caco-2 and LoVo cells in vitro, co-treatment with SMI (2 μL/mL) significantly enhanced the cytotoxicity of ADR and PTX, and resulted in some favorable pharmacokinetic changes in the subcellular distribution of ADR and PTX. In addition, SMI-induced intracellular accumulation of ADR was closely correlated with the increased expression levels of P-glycoprotein in 4 colon cancer cell lines (r(2)=+0.8558). SMI enhances the anti-cancer effects of ADR and PTX in colon cancers in vivo and in vitro by improving the subcellular distributions of ADR and PTX.

  8. Shenmai injection enhances the cytotoxicity of chemotherapeutic drugs against colorectal cancers via improving their subcellular distribution

    PubMed Central

    Liu, Wen-yue; Zhang, Jing-wei; Yao, Xue-quan; Jiang, Chao; He, Ji-chao; Ni, Pin; Liu, Jia-li; Chen, Qian-ying; Li, Qing-ran; Zang, Xiao-jie; Yao, Lan; Liu, Ya-zhong; Wang, Mu-lan; Shen, Pei-qiang; Wang, Guang-ji; Zhou, Fang

    2017-01-01

    Shenmai injection (SMI) is a Chinese patent-protected injection, which was mainly made of Red Ginseng and Radix Ophiopogonis and widely used for treating coronary heart disease and tumors by boosting Qi and nourishing Yin. In this study we examined whether SMI could produce direct synergetic effects on the cytoxicity of adriamycin (ADR) and paclitaxel (PTX) in colorectal cancers in vivo and in vitro, and explored the underlying pharmacokinetic mechanisms. BALB/c nude mice with LoVo colon cancer xenografts were intraperitoneally injected with ADR (2 mg·kg−1·3d−1) or PTX (7.5 mg·kg−1·3d−1) with or without SMI (0.01 mL·g−1·d−1) for 13 d. Co-administration of SMI significantly enhanced the chemotherapeutic efficacy of ADR and PTX, whereas administration of SMI alone at the given dosage did not produce visible anti-cancer effects, The chemosensitizing action of SMI was associated with increased concentrations of ADR and PTX in the plasma and tumors. In Caco-2 and LoVo cells in vitro, co-treatment with SMI (2 μL/mL) significantly enhanced the cytotoxicity of ADR and PTX, and resulted in some favorable pharmacokinetic changes in the subcellular distribution of ADR and PTX. In addition, SMI-induced intracellular accumulation of ADR was closely correlated with the increased expression levels of P-glycoprotein in 4 colon cancer cell lines (r2=+0.8558). SMI enhances the anti-cancer effects of ADR and PTX in colon cancers in vivo and in vitro by improving the subcellular distributions of ADR and PTX. PMID:27867186

  9. 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.

  10. 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.

  11. 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.

  12. Nano-chitosan particles in anticancer drug delivery: An up-to-date review.

    PubMed

    Kamath, Pooja R; Sunil, Dhanya

    2017-02-27

    Cancer is one of the most awful lethal diseases all over the world and the success of its current chemotherapeutic treatment strategies is limited due to several associated drawbacks. The exploration of cancer cell physiology and its microenvironment have exposed the potential of various classes of nanocarriers to deliver anticancer chemotherapeutic agents at the tumor target site. These nanocarriers must evade the immune surveillance system and achieve target selectivity. Besides, they must gain access in to the interior of cancerous cells, evade endosomal entrapment and discharge the drugs in a sustained manner. Chitosan, the second naturally abundant polysaccharide is a biocompatible, biodegradable and mucoadhesive cationic polymer which has been exploited extensively in the last few years in the effective delivery of anticancer chemotherapeutics to the target tumor cells. Therapeutic agent-loaded surface modified chitosan nanoparticles are established to be more stable, permeable and bioactive. This review will provide an up-to-date evidence-based background on recent pharmaceutical advancements in the transformation of chitosan nanoparticles for smart anticancer therapeutic drug delivery.

  13. Tuberculosis chemotherapy: current drug delivery approaches

    PubMed Central

    du Toit, Lisa Claire; Pillay, Viness; Danckwerts, Michael Paul

    2006-01-01

    Tuberculosis is a leading killer of young adults worldwide and the global scourge of multi-drug resistant tuberculosis is reaching epidemic proportions. It is endemic in most developing countries and resurgent in developed and developing countries with high rates of human immunodeficiency virus infection. This article reviews the current situation in terms of drug delivery approaches for tuberculosis chemotherapy. A number of novel implant-, microparticulate-, and various other carrier-based drug delivery systems incorporating the principal anti-tuberculosis agents have been fabricated that either target the site of tuberculosis infection or reduce the dosing frequency with the aim of improving patient outcomes. These developments in drug delivery represent attractive options with significant merit, however, there is a requisite to manufacture an oral system, which directly addresses issues of unacceptable rifampicin bioavailability in fixed-dose combinations. This is fostered by the need to deliver medications to patients more efficiently and with fewer side effects, especially in developing countries. The fabrication of a polymeric once-daily oral multiparticulate fixed-dose combination of the principal anti-tuberculosis drugs, which attains segregated delivery of rifampicin and isoniazid for improved rifampicin bioavailability, could be a step in the right direction in addressing issues of treatment failure due to patient non-compliance. PMID:16984627

  14. Chemotherapeutics-induced Oct4 expression contributes to drug resistance and tumor recurrence in bladder cancer

    PubMed Central

    Su, Bing-Hua; Su, Yu-Chu; Chen, Yi-Cheng; Su, Wu-Chou; Wu, Pensee; Yang, Wen-Horng; Shiau, Ai-Li; Wu, Chao-Liang

    2017-01-01

    Cancer cells initially characterized as sensitive to chemotherapy may acquire resistance to chemotherapy and lead to tumor recurrence through the expansion of drug-resistant population. Acquisition of drug resistance to conventional chemotherapy is a major obstacle in the treatment of recurrent cancer. Here we investigated whether anticancer drugs induced Oct4 expression, thereby contributing to acquired drug resistance and tumor recurrence in bladder cancer. We identified a positive correlation of Oct4 expression with tumor recurrence in 122 clinical specimens of superficial high-grade (stages T1-2) bladder transitional cell carcinoma (TCC). Increased Oct4 levels in bladder tumors were associated with short recurrence-free intervals in the patients. Chemotherapy induced Oct4 expression in bladder cancer cells. Notably, treatment with cisplatin increased CD44-positive bladder cancer cells expressing Oct4, representing cancer stem-like cell subpopulation. Forced expression of Oct4 reduced, whereas knockdown of Oct4 enhanced, drug sensitivity in bladder cancer cells. Furthermore, tumor cells overexpressing Oct4 responded poorly to cisplatin in vivo. In regard to clinical relevance, inhibition of Oct4 by all-trans retinoic acid (ATRA) synergistically increased sensitivity to cisplatin in bladder cancer cells. Furthermore, the combination of cisplatin and ATRA was superior to cisplatin alone in suppressing tumor growth. Therefore, our results provide evidence that Oct4 increases drug resistance and implicate that inhibition of Oct4 may be a therapeutic strategy to circumvent drug resistance. PMID:27244887

  15. SOX4 contributes to the progression of cervical cancer and the resistance to the chemotherapeutic drug through ABCG2

    PubMed Central

    Sun, R; Jiang, B; Qi, H; Zhang, X; Yang, J; Duan, J; Li, Y; Li, G

    2015-01-01

    SOX4, a member of the SOX (sex-determining region Y-related HMG box) transcription factor family, has been reported to be abnormally expressed in a wide variety of cancers, and to exert a pleiotropic function. However, its function in progression of cervical cancer (CC) remains unknown. In this study, we found that SOX4 was highly expressed in CC cells and tissues, and overexpression of SOX4 in CC CaSki cells enhanced tumor clone formation and cell proliferation, and accelerated cell cycle progress. Meanwhile, downregulation of SOX4 by shRNA in CaSki cells inhibited cell proliferation, and slowed cell cycle progress, indicating that SOX4 contributes to the development of CC. In addition, SOX4 overexpression by gene transfer reduced the sensitivity of CaSki cells in response to the chemotherapeutic drug cisplatin, and SOX4 downregulation by RNA interference increased the sensitivity of CaSki cells in response to cisplatin. Moreover, SOX4 overexpression upregulated multiple drug resistant gene ABCG2, and SOX4 downregulation inhibited ABCG2 expression. Taken together, these results suggested that SOX4 functions to modulate cancer proliferation by regulation of cell cycle, and inhibit cancer cell sensitivity to therapeutic drug via upregulation of ABCG2. Thus, SOX4 may be a target for CC chemotherapy. PMID:26583330

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

    PubMed Central

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

    2016-01-01

    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 Yb3+/Er3+ 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

  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

    2016-09-06

    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.

  18. Ingestion of drugs by "parachuting": a unique drug delivery technique.

    PubMed

    Kenerson, Katherine L; Lear-Kaul, Kelly C

    2012-06-01

    "Parachuting" is a technique of drug delivery where medications or illicit drugs are ingested by wrapping the drug of choice in a covering, which then will dissolve or unravel in the gastrointestinal tract, thereby releasing the drug for absorption. Parachuting of drugs can entail crushing of a pill prior to packaging to theoretically increase the surface area for absorption or may involve the packaging of a higher than usual dose of a drug in attempts to attain a sustained-release effect as the "parachute" dissolves or unravels. A case is presented in which a prescription drug abuser known to parachute his medications dies from obstruction of his airway by the inhaled packet. Risks of parachuting any drug would include overdose and fatal toxic effect from the drug itself and adverse effects from the packaging including bowel obstruction or perforation, or airway obstruction.

  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.

  20. Intracranial drug delivery for subarachnoid hemorrhage.

    PubMed

    Macdonald, Robert Loch; Leung, Ming; Tice, Tom

    2012-01-01

    Tice and colleagues pioneered site-specific, sustained-release drug delivery to the brain almost 30 years ago. Currently there is one drug approved for use in this manner. Clinical trials in subarachnoid hemorrhage have led to approval of nimodipine for oral and intravenous use, but other drugs, such as clazosentan, hydroxymethylglutaryl CoA reductase inhibitors (statins) and magnesium, have not shown consistent clinical efficacy. We propose that intracranial delivery of drugs such as nimodipine, formulated in sustained-release preparations, are good candidates for improving outcome after subarachnoid hemorrhage because they can be administered to patients that are already undergoing surgery and who have a self-limited condition from which full recovery is possible.

  1. Biodegradable Hybrid Stomatocyte Nanomotors for Drug Delivery.

    PubMed

    Tu, Yingfeng; Peng, Fei; André, Alain A M; Men, Yongjun; Srinivas, Mangala; Wilson, Daniela A

    2017-02-28

    We report the self-assembly of a biodegradable platinum nanoparticle-loaded stomatocyte nanomotor containing both PEG-b-PCL and PEG-b-PS as a potential candidate for anticancer drug delivery. Well-defined stomatocyte structures could be formed even after incorporation of 50% PEG-b-PCL polymer. Demixing of the two polymers was expected at high percentage of semicrystalline poly(ε-caprolactone) (PCL), resulting in PCL domain formation onto the membrane due to different properties of two polymers. The biodegradable motor system was further shown to move directionally with speeds up to 39 μm/s by converting chemical fuel, hydrogen peroxide, into mechanical motion as well as rapidly delivering the drug to the targeted cancer cell. Uptake by cancer cells and fast doxorubicin drug release was demonstrated during the degradation of the motor system. Such biodegradable nanomotors provide a convenient and efficient platform for the delivery and controlled release of therapeutic drugs.

  2. Biodegradable Hybrid Stomatocyte Nanomotors for Drug Delivery

    PubMed Central

    2017-01-01

    We report the self-assembly of a biodegradable platinum nanoparticle-loaded stomatocyte nanomotor containing both PEG-b-PCL and PEG-b-PS as a potential candidate for anticancer drug delivery. Well-defined stomatocyte structures could be formed even after incorporation of 50% PEG-b-PCL polymer. Demixing of the two polymers was expected at high percentage of semicrystalline poly(ε-caprolactone) (PCL), resulting in PCL domain formation onto the membrane due to different properties of two polymers. The biodegradable motor system was further shown to move directionally with speeds up to 39 μm/s by converting chemical fuel, hydrogen peroxide, into mechanical motion as well as rapidly delivering the drug to the targeted cancer cell. Uptake by cancer cells and fast doxorubicin drug release was demonstrated during the degradation of the motor system. Such biodegradable nanomotors provide a convenient and efficient platform for the delivery and controlled release of therapeutic drugs. PMID:28187254

  3. 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.

  4. Vaginal drug delivery systems for HIV prevention.

    PubMed

    Rohan, Lisa Cencia; Sassi, Alexandra B

    2009-03-01

    Microbicides have become a principal focus for HIV prevention strategies. The successful design of drug delivery systems for vaginal microbicide drug candidates brings with it a multitude of challenges. It is imperative that the chemical and physical characteristics of the drug candidate and its mechanism of action be clearly understood and considered to successfully deliver and target drug candidates efficiently. In addition, an understanding of the dynamic nature of the vaginal environment, the tissue and innate barriers present, as well as patient preferences are critical considerations in the design of effective microbicide products. Although the majority of drug candidates clinically evaluated to date have been delivered using conventional semisolid aqueous-based gel dosage forms, drug delivery system design has recently been extended to include advanced delivery systems such as vaginal rings, quick-dissolve films, and tablets. Ultimately, it may be necessary to develop multiple dosage platforms for a single active agent to provide users with options that can be used within the constraints of their social environment, personal choice, and environmental conditions.

  5. Pectin matrix as oral drug delivery vehicle for colon cancer treatment.

    PubMed

    Wong, Tin Wui; Colombo, Gaia; Sonvico, Fabio

    2011-03-01

    Colon cancer is the fourth most common cancer globally with 639,000 deaths reported annually. Typical chemotherapy is provided by injection route to reduce tumor growth and metastasis. Recent research investigates the oral delivery profiles of chemotherapeutic agents. In comparison to injection, oral administration of drugs in the form of a colon-specific delivery system is expected to increase drug bioavailability at target site, reduce drug dose and systemic adverse effects. Pectin is suitable for use as colon-specific drug delivery vehicle as it is selectively digested by colonic microflora to release drug with minimal degradation in upper gastrointestinal tract. The present review examines the physicochemical attributes of formulation needed to retard drug release of pectin matrix prior to its arrival at colon, and evaluate the therapeutic value of pectin matrix in association with colon cancer. The review suggests that multi-particulate calcium pectinate matrix is an ideal carrier to orally deliver drugs for site-specific treatment of colon cancer as (1) crosslinking of pectin by calcium ions in a matrix negates drug release in upper gastrointestinal tract, (2) multi-particulate carrier has a slower transit and a higher contact time for drug action in colon than single-unit dosage form, and (3) both pectin and calcium have an indication to reduce the severity of colon cancer from the implication of diet and molecular biology studies. Pectin matrix demonstrates dual advantages as drug carrier and therapeutic for use in treatment of colon cancer.

  6. A 3D-printed local drug delivery patch for pancreatic cancer growth suppression.

    PubMed

    Yi, Hee-Gyeong; Choi, Yeong-Jin; Kang, Kyung Shin; Hong, Jung Min; Pati, Ruby Gupta; Park, Moon Nyeo; Shim, In Kyong; Lee, Chan Mi; Kim, Song Cheol; Cho, Dong-Woo

    2016-09-28

    Since recurrence and metastasis of pancreatic cancer has a worse prognosis, chemotherapy has been typically performed to attack the remained malignant cells after resection. However, it is difficult to achieve the therapeutic concentration at the tumor site with systemic chemotherapy. Numerous local drug delivery systems have been studied to overcome the shortcomings of systemic delivery. However, because most systems involve dissolution of the drug within the carrier, the concentration of the drug is limited to the saturation solubility, and consequently cannot reach the sufficient drug dose. Therefore, we hypothesized that 3D printing of a biodegradable patch incorporated with a high drug concentration would provide a versatile shape to be administered at the exact tumor site as well as an appropriate therapeutic drug concentration with a controlled release. Here, we introduce the 3D-printed patches composed of a blend of poly(lactide-co-glycolide), polycaprolactone, and 5-fluorouracil for delivering the anti-cancer drug in a prolonged controlled manner and therapeutic dose. 3D printing technology can manipulate the geometry of the patch and the drug release kinetics. The patches were flexible, and released the drug over four weeks, and thereby suppressed growth of the subcutaneous pancreatic cancer xenografts in mice with minimized side effects. Our approach reveals that 3D printing of bioabsorbable implants containing anti-cancer drugs could be a powerful method for an effective local delivery of chemotherapeutic agents to treatment of cancers.

  7. 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

  8. Drug Delivery for Peripheral Nerve Regeneration

    DTIC Science & Technology

    2015-11-01

    Gale)(months 0-1) b. Optimize nanoporous membrane dimensions ......................(Gale...kinetics of NGF in vitro using our novel drug delivery conduit Material Fabrication The proposed device consists of two concentric tubes, a reservoir...suctioning of material into the conduits, any excess PLGA was allowed to drip out of the molds. The conduits were then placed vertically into a water

  9. Drug delivery strategies for poorly water-soluble drugs.

    PubMed

    Fahr, Alfred; Liu, Xiangli

    2007-07-01

    The drug candidates coming from combinatorial chemistry research and/or the drugs selected from biologically based high-throughput screening are quite often very lipophilic, as these drug candidates exert their pharmacological action at or in biological membranes or membrane-associated proteins. This challenges drug delivery institutions in industry or academia to develop carrier systems for the optimal oral and parenteral administration of these drugs. To mention only a few of the challenges for this class of drugs: their oral bioavailability is poor and highly variable, and carrier development for parenteral administration is faced with problems, including the massive use of surface-active excipients for solubilisation. Formulation specialists are confronted with an even higher level of difficulties when these drugs have to be delivered site specifically. This article addresses the emerging formulation designs for delivering of poorly water-soluble drugs.

  10. Bitter melon extracts enhance the activity of chemotherapeutic agents through the modulation of multiple drug resistance

    PubMed Central

    Kwatra, Deep; Venugopal, Anand; Standing, David; Ponnurangam, Sivapriya; Dhar, Animesh; Mitra, Ashim; Anant, Shrikant

    2014-01-01

    Recently we demonstrated that extracts of bitter melon (BME) can be used as a preventive/therapeutic agent in colon cancers. Here, we determined BME effects on anticancer activity and bioavailability of doxorubicin (DOX) in colon cancer cells. BME enhanced the effect of DOX on cell proliferation and sensitized the cells towards DOX upon pretreatment. Furthermore, there was both increased drug uptake and reduced drug efflux. We also observed a reduction in the expression of Multidrug resistance conferring proteins (MDRCP) P-glycoprotein, MRP-2 and BCRP. Further BME suppressed DOX efflux in MDCK cells overexpressing the three efflux proteins individually, suggesting that BME is a potent inhibitor of MDR function. Next, we determined the effect of BME on PXR, a xenobiotic sensing nuclear receptor and a transcription factor that controls the expression of the three MDR genes. BME suppressed PXR promoter activity thereby suppressing its expression. Finally, we determined the effect of AMPK pathway on drug efflux because we have previously demonstrated that BME affects the pathway. However, inhibiting AMPK did not affect drug resistance, suggesting that BME may use different pathways for the anticancer and MDR modulating activities. Together, these results suggest that BME can enhance the bioavailability and efficacy of conventional chemotherapy. PMID:24129966

  11. Degradation of P-glycoprotein by pristimerin contributes to overcoming ABCB1-mediated chemotherapeutic drug resistance in vitro

    PubMed Central

    Yan, Yan-Yan; Wang, Fang; Zhao, Xiao-Qin; Wang, Xiao-Kun; Chen, Yi-Fan; Liu, Hong; Xie, Yong; Fu, Li-Wu

    2016-01-01

    ABCB1 (P-glycoprotein, ABCB1/MDR1) is one of the major members of the ABC transporters linked to MDR in cancer cells. In this study, we observed that pristimerin, a natural triterpenoid, potently decreased P-gp in a dose-dependent manner in both drug-resistant KBv200 and stable transfected HEK293/ABCB1 cell lines. Moreover, pristimerin also inhibited cell proliferation and induced apoptosis in both cell lines. Intriguingly, reverse transcription-PCR, real-time PCR and protein turn-over assay revealed that the decrease of P-gp was independent of mRNA level but primarily owing to its protein stability. Furthermore, immunofluorescence study with anti-P-gp antibody showed that pristimerin disturbed the subcellular distribution of P-gp with decreased location in the plasma membrane. Taken together, these data suggest that subcellular distribution of P-gp and subsequent downregulation by pristimerin contribute to overcoming ABCB1-mediated chemotherapeutic drug resistance. Our findings suggested inducing the decrease of P-gp membrane protein could be a new promising alternative therapeutic strategy in ABCB1-mediated MDR. PMID:27840996

  12. Potential new methods for antiepileptic drug delivery.

    PubMed

    Fisher, Robert S; Ho, Jet

    2002-01-01

    Use of novel drug delivery methods could enhance the efficacy and reduce the toxicity of antiepileptic drugs (AEDs). Slow-release oral forms of medication or depot drugs such as skin patches might improve compliance and therefore seizure control. In emergency situations, administration via rectal, nasal or buccal mucosa can deliver the drug more quickly than can oral administration. Slow-release oral forms and rectal forms of AEDs are already approved for use, nasal and buccal administration is currently off-label and skin patches for AEDs are an attractive but currently hypothetical option. Therapies under development may result in the delivery of AEDs directly to the regions of the brain involved in seizures. Experimental protocols are underway to allow continuous infusion of potent excitatory amino acid antagonists into the CSF. In experiments with animal models of epilepsy, AEDs have been delivered successfully to seizure foci in the brain by programmed infusion pumps, acting in response to computerised EEG seizure detection. Inactive prodrugs can be given systemically and activated at the site of the seizure focus by locally released compounds. One such drug under development is DP-VPA (or DP16), which is cleaved to valproic acid (sodium valproate) by phospholipases at the seizure focus. Liposomes and nanoparticles are engineered micro-reservoirs of a drug, with attached antibodies or receptor-specific binding agents designed to target the particles to a specific region of the body. Liposomes in theory could deliver a high concentration of an AED to a seizure focus. Penetration of the blood-brain barrier can be accomplished by linking large particles to iron transferrin or biological toxins that can cross the barrier. In the near future, it is likely that cell transplants that generate neurotransmitters and neuromodulators will accomplish renewable endogenous drug delivery. However, the survival and viability of transplanted cells have yet to be demonstrated

  13. Mucoadhesive drug delivery system: An overview

    PubMed Central

    Boddupalli, Bindu M.; Mohammed, Zulkar N. K.; Nath, Ravinder A.; Banji, David

    2010-01-01

    Mucoadhesive drug delivery systems interact with the mucus layer covering the mucosal epithelial surface, and mucin molecules and increase the residence time of the dosage form at the site of absorption. The drugs which have local action or those which have maximum absorption in gastrointestinal tract (GIT) require increased duration of stay in GIT. Thus, mucoadhesive dosage forms are advantageous in increasing the drug plasma concentrations and also therapeutic activity. In this regard, this review covers the areas of mechanisms and theories of mucoadhesion, factors influencing the mucoadhesive devices and also various mucoadhesive dosage forms. PMID:22247877

  14. Implications of nanoscale based drug delivery systems in delivery and targeting tubulin binding agent, noscapine in cancer cells.

    PubMed

    Chandra, Ramesh; Madan, Jitender; Singh, Prashant; Chandra, Ankush; Kumar, Pradeep; Tomar, Vartika; Dass, Sujata K

    2012-12-01

    Noscapine, a tubulin binding anticancer agent undergoing Phase I/II clinical trials, inhibits tumor growth in nude mice bearing human xenografts of breast, lung, ovarian, brain, and prostrate origin. The analogues of noscapine like 9-bromonoscapine (EM011) are 5 to 10-fold more active than parent compound, noscapine. Noscapinoids inhibit the proliferation of cancer cells that are resistant to paclitaxel and epothilone. Noscapine also potentiated the anticancer activity of doxorubicin in a synergistic manner against triple negative breast cancer (TNBC). However, physicochemical and pharmacokinetic (ED50˜300-600 mg/kg bodyweight) limitations of noscapine present hurdle in development of commercial anticancer formulations. Therefore, objectives of the present review are to summarize the chemotherapeutic potential of noscapine and implications of nanoscale based drug delivery systems in enhancing the therapeutic efficacy of noscapine in cancer cells. We have constructed noscapine-enveloped gelatin nanoparticles, NPs and poly (ethylene glycol) grafted gelatin NPs as well as inclusion complex of noscapine in β-cyclodextrin (β-CD) and evaluated their physicochemical characteristics. The Fe3O4 NPs were also used to incorporate noscapine in its polymeric nanomatrix system where molecular weight of the polymer governed the encapsulation efficiency of drug. The enhanced noscapine delivery using μPAR-targeted optical-MR imaging trackable NPs offer a great potential for image directed targeted delivery of noscapine. Human Serum Albumin NPs (150-300 nm) as efficient noscapine drug delivery systems have also been developed for potential use in breast cancer.

  15. Advanced materials and nanotechnology for drug delivery.

    PubMed

    Yan, Li; Yang, Yang; Zhang, Wenjun; Chen, Xianfeng

    2014-08-20

    Many biological barriers are of great importance. For example, stratum corneum, the outmost layer of skin, effectively protects people from being invaded by external microorganisms such as bacteria and viruses. Cell membranes help organisms maintain homeostasis by controlling substances to enter and leave cells. However, on the other hand, these biological barriers seriously restrict drug delivery. For instance, stratum corneum has a very dense structure and only allows very small molecules with a molecular weight of below 500 Da to permeate whereas most drug molecules are much larger than that. A wide variety of drugs including genes needs to enter cells for proper functioning but cell membranes are not permeable to them. To overcome these biological barriers, many drug-delivery routes are being actively researched and developed. In this research news, we will focus on two advanced materials and nanotechnology approaches for delivering vaccines through the skin for painless and efficient immunization and transporting drug molecules to cross cell membranes for high-throughput intracellular delivery. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Structural DNA nanotechnology for intelligent drug delivery.

    PubMed

    Chao, Jie; Liu, Huajie; Su, Shao; Wang, Lianhui; Huang, Wei; Fan, Chunhai

    2014-11-01

    Drug delivery carriers have been popularly employed to improve solubility, stability, and efficacy of chemical and biomolecular drugs. Despite the rapid progress in this field, it remains a great challenge to develop an ideal carrier with minimal cytotoxicity, high biocompatibility and intelligence for targeted controlled release. The emergence of DNA nanotechnology offers unprecedented opportunities in this regard. Due to the unparalleled self-recognition properties of DNA molecules, it is possible to create numerous artificial DNA nanostructures with well-defined structures and DNA nanodevices with precisely controlled motions. More importantly, recent studies have proven that DNA nanostructures possess greater permeability to the membrane barrier of cells, which pave the way to developing new drug delivery carriers with nucleic acids, are summarized. In this Concept, recent advances on the design and fabrication of both static and dynamic DNA nanostructures, and the use of these nanostructures for the delivery of various types of drugs, are highlighted. It is also demonstrated that dynamic DNA nanostructures provide the required intelligence to realize logically controlled drug release. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Oral transmucosal drug delivery for pediatric use.

    PubMed

    Lam, Jenny K W; Xu, Yingying; Worsley, Alan; Wong, Ian C K

    2014-06-01

    The formulation of medicines for children remains a challenge. An ideal pediatric formulation must allow accurate dose administration and be in a dosage form that can be handled by the target age group. It is also important to consider the choices and the amount of excipients used in the formulation for this vulnerable age group. Although oral formulations are generally acceptable to most pediatric patients, they are not suitable for drugs with poor oral bioavailability or when a rapid clinical effect is required. In recent years, oral transmucosal delivery has emerged as an attractive route of administration for pediatric patients. With this route of administration, a drug is absorbed through the oral mucosa, therefore bypassing hepatic first pass metabolism and thus avoiding drug degradation or metabolism in the gastrointestinal tract. The high blood flow and relatively high permeability of the oral mucosa allow a quick onset of action to be achieved. It is a simple and non-invasive route of drug administration. However, there are several barriers that need to be overcome in the development of oral transmucosal products. This article aims to provide a comprehensive review of the current development of oral transmucosal delivery specifically for the pediatric population in order to achieve systemic drug delivery. The anatomical and physiological properties of the oral mucosa of infants and young children are carefully examined. The different dosage forms and formulation strategies that are suitable for young patients are discussed.

  18. Chitosan magnetic nanoparticles for drug delivery systems.

    PubMed

    Assa, Farnaz; Jafarizadeh-Malmiri, Hoda; Ajamein, Hossein; Vaghari, Hamideh; Anarjan, Navideh; Ahmadi, Omid; Berenjian, Aydin

    2017-06-01

    The potential of magnetic nanoparticles (MNPs) in drug delivery systems (DDSs) is mainly related to its magnetic core and surface coating. These coatings can eliminate or minimize their aggregation under physiological conditions. Also, they can provide functional groups for bioconjugation to anticancer drugs and/or targeted ligands. Chitosan, as a derivative of chitin, is an attractive natural biopolymer from renewable resources with the presence of reactive amino and hydroxyl functional groups in its structure. Chitosan nanoparticles (NPs), due to their huge surface to volume ratio as compared to the chitosan in its bulk form, have outstanding physico-chemical, antimicrobial and biological properties. These unique properties make chitosan NPs a promising biopolymer for the application of DDSs. In this review, the current state and challenges for the application magnetic chitosan NPs in drug delivery systems were investigated. The present review also revisits the limitations and commercial impediments to provide insight for future works.

  19. A minimum core outcome dataset for the reporting of preclinical chemotherapeutic drug studies: Lessons learned from multiple discordant methodologies in the setting of colorectal cancer.

    PubMed

    West, M A; Roman, A; Sayan, E; Primrose, J N; Wedge, S R; Underwood, T J; Mirnezami, A H

    2017-04-01

    In vivo studies in animal models are critical tools necessary to study the fundamental complexity of carcinogenesis. A constant strive to improve animal models in cancer exists, especially those investigating the use of chemotherapeutic effectiveness. In the present systematic review, colorectal cancer (CRC) is used as an example to highlight and critically evaluate the range of reporting strategies used when investigating chemotherapeutic agents in the preclinical setting. A systematic review examining the methodology and reporting of preclinical chemotherapeutic drug studies using CRC murine models was conducted. A total of 45 studies were included in this systematic review. The literature was found to be highly heterogeneous with various cell lines, animal strains, animal ages and chemotherapeutic compounds/regimens tested, proving difficult to compare outcomes between similar studies or indeed gain any significant insight into which chemotherapeutic regimen caused adverse events. From this analysis we propose a minimum core outcome dataset that could be regarded as a standardised way of reporting results from in vivo experimentation.

  20. Targeted Drug Delivery Systems Mediated by a Novel Peptide in Breast Cancer Therapy and Imaging

    PubMed Central

    Chiu, Chien-Yu; Lin, Wei-Chuan; Yan, Shin-Long; Wang, Yi-Ping; Kuo, Yuan-Sung; Yeh, Chen-Yun; Lo, Albert; Wu, Han-Chung

    2013-01-01

    Targeted delivery of drugs to tumors represents a significant advance in cancer diagnosis and therapy. Therefore, development of novel tumor-specific ligands or pharmaceutical nanocarriers is highly desirable. In this study, we utilized phage display to identify a new targeting peptide, SP90, which specifically binds to breast cancer cells, and recognizes tumor tissues from breast cancer patients. We used confocal and electron microscopy to reveal that conjugation of SP90 with liposomes enables efficient delivery of drugs into cancer cells through endocytosis. Furthermore, in vivo fluorescent imaging demonstrated that SP90-conjugated quantum dots possess tumor-targeting properties. In tumor xenograft and orthotopic models, SP90-conjugated liposomal doxorubicin was found to improve the therapeutic index of the chemotherapeutic drug by selectively increasing its accumulation in tumors. We conclude that the targeting peptide SP90 has significant potential in improving the clinical benefits of chemotherapy in the treatment and the diagnosis of breast cancer. PMID:23776619

  1. Current trends in the use of vitamin E-based micellar nanocarriers for anticancer drug delivery.

    PubMed

    Muddineti, Omkara Swami; Ghosh, Balaram; Biswas, Swati

    2017-06-01

    Owing to the complexity of cancer pathogenesis, conventional chemotherapy can be an inadequate method of killing cancer cells effectively. Nanoparticle-based drug delivery systems have been widely exploited pre-clinically in recent years. Areas covered: Incorporation of vitamin-E in nanocarriers have the advantage of (1) improving the hydrophobicity of the drug delivery system, thereby improving the solubility of the loaded poorly soluble anticancer drugs, (2) enhancing the biocompatibility of the polymeric drug carriers, and (3) improving the anticancer potential of the chemotherapeutic agents by reversing the cellular drug resistance via simultaneous administration. In addition to being a powerful antioxidant, vitamin E demonstrated its anticancer potential by inducing apoptosis in various cancer cell lines. Various vitamin E analogs have proven their ability to cause marked inhibition of drug efflux transporters. Expert opinion: The review discusses the potential of incorporating vitamin E in the polymeric micelles which are designed to carry poorly water-soluble anticancer drugs. Current applications of various vitamin E-based polymeric micelles with emphasis on the use of α-tocopherol, D-α-tocopheryl succinate (α-TOS) and its conjugates such as D-α-tocopheryl polyethylene glycol-succinate (TPGS) in micellar system is delineated. Advantages of utilizing polymeric micelles for drug delivery and the challenges to treat cancer, including multiple drug resistance have been discussed.

  2. [Dacarbazine, a chemotherapeutic against metastatic melanoma and a reference drug for new treatment modalities].

    PubMed

    Koprowska, Kamila; Czyż, Małgorzata

    2011-11-23

    Melanoma is a tumour derived from melanocytes, cells of neuroectodermal origin. Melanoma treatment represents a challenge to oncologists due to its aggressive course and early and multiple metastases. Surgical excision of lesions is a highly effective intervention, but only in early stages. In contrast, median survival of patients with metastatic melanoma is still below one year. In 2011 the FDA and EMA have approved new drugs, ipilimumab and vemurafenib, that might be a major breakthrough in treating patients with advanced melanoma. However, time is needed to conclude whether they replace dacarbazine, a drug used for over 30 years in the therapy of metastatic melanoma, even if the response rate was only 10-15%. The mechanism of dacarbazine action is not clear but it is probably based on methylation of purine bases in DNA. The low therapeutic efficacy of dacarbazine might be the consequence of rapid removal of DNA lesions by repair systems. A high melanoma chemoresistance is also driven by the extent and nature of alterations in signal transductions in tumour cells. None of the previously conducted trials proved superiority of any treatment modality over monotherapy with dacarbazine. Higher response rates did not correlate with survival benefit, and more intense adverse effects were frequently observed. There are some expectations for targeted therapy and immunotherapy, which have already demonstrated some efficacy in clinical studies. This review aims at providing the current knowledge on dacarbazine and its analogue, temozolomide, including the latest results of clinical studies combining these drugs with other treatment protocols.

  3. Mucoadhesive polymeric platforms for controlled drug delivery.

    PubMed

    Andrews, Gavin P; Laverty, Thomas P; Jones, David S

    2009-03-01

    The process of mucoadhesion involving a polymeric drug delivery platform is a complex one that includes wetting, adsorption and interpenetration of polymer chains amongst various other processes. The success and degree of mucoadhesion bonding is influenced by various polymer-based properties such as the degree of cross-linking, chain length and the presence of various functional groupings. The attractiveness of mucosal-targeted controlled drug delivery of active pharmaceutical ingredients (APIs), has led formulation scientists to engineer numerous polymeric systems for such tasks. Formulation scientists have at their disposal a range of in vitro and in vivo mucoadhesion testing setups in order to select candidate adhesive drug delivery platforms. As such, mucoadhesive systems have found wide use throughout many mucosal covered organelles for API delivery for local or systemic effect. Evolution of such mucoadhesive formulations has transgressed from first-generation charged hydrophilic polymer networks to more specific second-generation systems based on lectin, thiol and various other adhesive functional groups.

  4. Folic acid-conjugated amphiphilic alternating copolymer as a new active tumor targeting drug delivery platform

    PubMed Central

    Li, Xia; Szewczuk, Myron R; Malardier-Jugroot, Cecile

    2016-01-01

    Targeted drug delivery using polymeric nanostructures is an emerging cancer research area, engineered for safer, more efficient, and effective use of chemotherapeutic drugs. A pH-responsive, active targeting delivery system was designed using folic acid functionalized amphiphilic alternating copolymer poly(styrene-alt-maleic anhydride) (FA-DABA-SMA) via a biodegradable linker 2,4-diaminobutyric acid (DABA). The polymeric template is pH responsive, forming amphiphilic nanostructures at pH 7, allowing the encapsulation of hydrophobic drugs on its interior. Moreover, the structure is stable only at neutral pH and collapses in the acidic tumor microenvironment, releasing drugs on-site from its core. The delivery vehicle is investigated using human pancreatic PANC-1 cancer cells and RAW-Blue™ mouse macrophage reporter cell line, both of which have overly expression of folic acid receptors. To trace the cellular uptake by both cell lines, curcumin was selected as a dye and drug mimic owing to its fluorescence nature and hydrophobic properties. Fluorescent microscopy of FA-DABA-SMA loaded with curcumin revealed a significant internalization of the dye by human pancreatic PANC-1 cancer cells compared to those with unfunctionalized polymers (SMA). Moreover, the FA-DABA-SMA polymers exhibit rodlike association specific to the cells. Both empty SMA and FA-DABA-SMA show little toxicity to PANC-1 cells as characterized by WST-1 cell proliferation assay. These results clearly indicate that FA-DABA-SMA polymers show potential as an active tumor targeting drug delivery system with the ability to internalize hydrophobic chemotherapeutics after they specifically attach to cancer cells. PMID:28008233

  5. Drug delivery optimization through Bayesian networks.

    PubMed Central

    Bellazzi, R.

    1992-01-01

    This paper describes how Bayesian Networks can be used in combination with compartmental models to plan Recombinant Human Erythropoietin (r-HuEPO) delivery in the treatment of anemia of chronic uremic patients. Past measurements of hematocrit or hemoglobin concentration in a patient during the therapy can be exploited to adjust the parameters of a compartmental model of the erythropoiesis. This adaptive process allows more accurate patient-specific predictions, and hence a more rational dosage planning. We describe a drug delivery optimization protocol, based on our approach. Some results obtained on real data are presented. PMID:1482938

  6. Mucoadhesive in situ nasal gelling drug delivery systems for modulated drug delivery.

    PubMed

    Singh, Reena M P; Kumar, Anil; Pathak, Kamla

    2013-01-01

    The nasal route is an attractive target for administration of the drug of choice, particularly in overcoming disadvantages such as high first-pass metabolism and drug degradation in the gastrointestinal environment that are associated with the oral and other modes of administration. The major limitation associated is of rapid mucociliary clearance in the nasal delivery that results in low absorption and hence poor bioavailability. In order to overcome this, mucoadhesive in situ nasal gelling drug delivery systems have been explored to develop sustained/controlled delivery via nasal route. The present review critically evaluates the importance of in situ gel for the nasal delivery of drugs, and the polymers used in the formulation of in situ gel along with their mechanism of gelation. It also encompasses the research reports made in this arena of delivery system. The challenges of drug delivery through nose has led to development of in situ nasal gelling systems using a myriad of polymers to deliver the drugs, proteins, amino acids, hormones, vaccines and plasmid DNA for the local, systemic and central nervous system effects. Though a range of preclinical reports are available, clinical intricacies need to be critically worked out.

  7. Multifunctional High Drug Loading Nanocarriers for Cancer Drug Delivery

    NASA Astrophysics Data System (ADS)

    Jin, Erlei

    2011-12-01

    Most anticancer drugs have poor water-solubility, rapid blood clearance, low tumor-selectivity and severe systemic toxicity to healthy tissues. Thus, polymeric nanocarriers have been widely explored for anticancer drugs to solve these problems. However, polymer nanocarriers developed to date still suffer drawbacks including low drug loading contents, premature drug release, slow cellular internalization, slow intracellular drug release and thereby low therapeutic efficiency in cancer thermotherapy. Accordingly, in this dissertation, functional nanocapsules and nanoparticles including high drug loading liposome-like nanocapsules, high drug loading phospholipid-mimic nanocapsules with fast intracellular drug release, high drug loading charge-reversal nanocapsules, TAT based long blood circulation nanoparticles and charge-reversal nuclear targeted nanoparticles are designed and synthesized. These functional carriers have advantages such as high drug loading contents without premature drug release, fast cellular internalization and intracellular drug release, nuclear targeted delivery and long blood circulation. As a result, all these drug carriers show much higher in vitro and in vivo anti-cancer activities.

  8. Evaluation of Chemotherapeutic Agents Against Malaria, Drugs, Diet, and Biological Response Modifiers.

    DTIC Science & Technology

    1991-10-29

    In experiment 76 the antioxidant Coenzyme Q10 (ubiquinone 50) was tested to see if it would replace vitamin E as an antioxidant and influence the...low whether started at 3 weeks of age or 4 weeks of age. 49 In experiment 76 the antioxidant coenzyme Q10 (ubiquinone 50) administered PO at 100, 36 or...line has remained stable under drug pressure for this year. Co-enzyme Q10 did not act as an antioxidant like vitamin E during a malarial infection

  9. A new brain drug delivery strategy: focused ultrasound-enhanced intranasal drug delivery.

    PubMed

    Chen, Hong; Chen, Cherry C; Acosta, Camilo; Wu, Shih-Ying; Sun, Tao; Konofagou, Elisa E

    2014-01-01

    Central nervous system (CNS) diseases are difficult to treat because of the blood-brain barrier (BBB), which prevents most drugs from entering into the brain. Intranasal (i.n.) administration is a promising approach for drug delivery to the brain, bypassing the BBB; however, its application has been restricted to particularly potent substances and it does not offer localized delivery to specific brain sites. Focused ultrasound (FUS) in combination with microbubbles can deliver drugs to the brain at targeted locations. The present study proposed to combine these two different platform techniques (FUS+i.n.) for enhancing the delivery efficiency of intranasally administered drugs at a targeted location. After i.n. administration of 40 kDa fluorescently-labeled dextran as the model drug, FUS targeted at one region within the caudate putamen of mouse brains was applied in the presence of systemically administered microbubbles. To compare with the conventional FUS technique, in which intravenous (i.v.) drug injection is employed, FUS was also applied after i.v. injection of the same amount of dextran in another group of mice. Dextran delivery outcomes were evaluated using fluorescence imaging of brain slices. The results showed that FUS+i.n. enhanced drug delivery within the targeted region compared with that achieved by i.n. only. Despite the fact that the i.n. route has limited drug absorption across the nasal mucosa, the delivery efficiency of FUS+i.n. was not significantly different from that of FUS+i.v.. As a new drug delivery platform, the FUS+i.n. technique is potentially useful for treating CNS diseases.

  10. A New Brain Drug Delivery Strategy: Focused Ultrasound-Enhanced Intranasal Drug Delivery

    PubMed Central

    Chen, Hong; Chen, Cherry C.; Acosta, Camilo; Wu, Shih-Ying; Sun, Tao; Konofagou, Elisa E.

    2014-01-01

    Central nervous system (CNS) diseases are difficult to treat because of the blood-brain barrier (BBB), which prevents most drugs from entering into the brain. Intranasal (IN) administration is a promising approach for drug delivery to the brain, bypassing the BBB; however, its application has been restricted to particularly potent substances and it does not offer localized delivery to specific brain sites. Focused ultrasound (FUS) in combination with microbubbles can deliver drugs to the brain at targeted locations. The present study proposed to combine these two different platform techniques (FUS+IN) for enhancing the delivery efficiency of intranasally administered drugs at a targeted location. After IN administration of 40 kDa fluorescently-labeled dextran as the model drug, FUS targeted at one region within the caudate putamen of mouse brains was applied in the presence of systemically administered microbubbles. To compare with the conventional FUS technique, in which intravenous (IV) drug injection is employed, FUS was also applied after IV injection of the same amount of dextran in another group of mice. Dextran delivery outcomes were evaluated using fluorescence imaging of brain slices. The results showed that FUS+IN enhanced drug delivery within the targeted region compared with that achieved by IN only. Despite the fact that the IN route has limited drug absorption across the nasal mucosa, the delivery efficiency of FUS+IN was not significantly different from that of FUS+IV. As a new drug delivery platform, the FUS+IN technique is potentially useful for treating CNS diseases. PMID:25279463

  11. 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.

  12. 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

  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. The exciting potential of nanotherapy in brain-tumor targeted drug delivery approaches

    PubMed Central

    Agrahari, Vivek

    2017-01-01

    Delivering therapeutics to the central nervous system (CNS) and brain-tumor has been a major challenge. The current standard treatment approaches for the brain-tumor comprise of surgical resection followed by immunotherapy, radiotherapy, and chemotherapy. However, the current treatments are limited in providing significant benefits to the patients and despite recent technological advancements; brain-tumor is still challenging to treat. Brain-tumor therapy is limited by the lack of effective and targeted strategies to deliver chemotherapeutic agents across the blood-brain barrier (BBB). The BBB is the main obstacle that must be overcome to allow compounds to reach their targets in the brain. Recent advances have boosted the nanotherapeutic approaches in providing an attractive strategy in improving the drug delivery across the BBB and into the CNS. Compared to conventional formulations, nanoformulations offer significant advantages in CNS drug delivery approaches. Considering the above facts, in this review, the physiological/anatomical features of the brain-tumor and the BBB are briefly discussed. The drug transport mechanisms at the BBB are outlined. The approaches to deliver chemotherapeutic drugs across the CNS into the brain-tumor using nanocarriers are summarized. In addition, the challenges that need to be addressed in nanotherapeutic approaches for their enhanced clinical application in brain-tumor therapy are discussed. PMID:28400793

  15. Limited Efficiency of Drug Delivery to Specific Intracellular Organelles Using Subcellularly "Targeted" Drug Delivery Systems.

    PubMed

    Maity, Amit Ranjan; Stepensky, David

    2016-01-04

    Many drugs have been designed to act on intracellular targets and to affect intracellular processes inside target cells. For the desired effects to be exerted, these drugs should permeate target cells and reach specific intracellular organelles. This subcellular drug targeting approach has been proposed for enhancement of accumulation of these drugs in target organelles and improved efficiency. This approach is based on drug encapsulation in drug delivery systems (DDSs) and/or their decoration with specific targeting moieties that are intended to enhance the drug/DDS accumulation in the intracellular organelle of interest. During recent years, there has been a constant increase in interest in DDSs targeted to specific intracellular organelles, and many different approaches have been proposed for attaining efficient drug delivery to specific organelles of interest. However, it appears that in many studies insufficient efforts have been devoted to quantitative analysis of the major formulation parameters of the DDSs disposition (efficiency of DDS endocytosis and endosomal escape, intracellular trafficking, and efficiency of DDS delivery to the target organelle) and of the resulting pharmacological effects. Thus, in many cases, claims regarding efficient delivery of drug/DDS to a specific organelle and efficient subcellular targeting appear to be exaggerated. On the basis of the available experimental data, it appears that drugs/DDS decoration with specific targeting residues can affect their intracellular fate and result in preferential drug accumulation within an organelle of interest. However, it is not clear whether these approaches will be efficient in in vivo settings and be translated into preclinical and clinical applications. Studies that quantitatively assess the mechanisms, barriers, and efficiencies of subcellular drug delivery and of the associated toxic effects are required to determine the therapeutic potential of subcellular DDS targeting.

  16. Pharmacokinetics of the chemoprophylactic and chemotherapeutic trypanocidal drug isometamidium chloride (Samorin) in cattle.

    PubMed

    Eisler, M C

    1996-12-01

    Pharmacokinetics of the prophylactic and therapeutic trypanocidal drug isometamidium chloride were examined comprehensively for the first time in cattle using a recently described, highly sensitive ELISA. Cattle were administered single intravenous (N = 4) or intramuscular (N = 5) doses of isometamidium at a rate of 1.0 mg x kg(-1) body weight. Concentration data were analyzed over at least 14 days (intravenous treatment) or 30 days (intramuscular treatment) using compartmental and noncompartmental methods. After intravenous administration, apparent volumes of the central compartment (mean = 0.695 liter x kg(-1); range = 0.59-0.95) were large, and volumes of distribution at steady-state (mean = 24.5 liter x kg(-1): range = 18.5-39.3) were particularly large. After intramuscular administration, there was considerable individual variability in Cmax (mean = 111 ng x ml(-1); range = 37-197) and other pharmacokinetic parameters. Absorption kinetics seemed to be multifunctional, with fast and slow components; the mean t(max) was only 36 min (range = 20-60), although the mean absorption time was 282 hr, and the mean terminal elimination phase half-life after intramuscular administration (286 hr; range = 215-463) was over twice that after intravenous administration (mean = 135 hr; range = 123-165). The overall absolute bioavailability of intramuscular-administered isometamidium was 65.7%. These findings were consistent with extensive tissue binding at the intramuscular injection site to form a primary depot responsible for most of the prolonged chemoprophylactic effect of isometamidium, and an additional role for significant secondary drug depots formed by tissue binding elsewhere, particularly after intravenous administration.

  17. Transdermal drug delivery: from micro to nano

    NASA Astrophysics Data System (ADS)

    Pegoraro, Carla; MacNeil, Sheila; Battaglia, Giuseppe

    2012-03-01

    Delivery across skin offers many advantages compared to oral or intravenous routes of drug administration. Skin however is highly impermeable to most molecules on the basis of size, hydrophilicity, lipophilicity and charge. For this reason it is often necessary to temporarily alter the barrier properties of skin for effective administration. This can be done by applying chemical enhancers, which alter the lipid structure of the top layer of skin (the stratum corneum, SC), by applying external forces such as electric currents and ultrasounds, by bypassing the stratum corneum via minimally invasive microneedles or by using nano-delivery vehicles that can cross and deliver their payload to the deeper layers of skin. Here we present a critical summary of the latest technologies used to increase transdermal delivery.

  18. Liposomal systems as viable drug delivery technology for skin cancer sites with an outlook on lipid-based delivery vehicles and diagnostic imaging inputs for skin conditions'.

    PubMed

    Akhtar, Naseem; Khan, Riaz A

    2016-10-01

    Skin cancer is among one of the most common human malignancies wide-spread world-over with mortality statistics rising continuously at an alarming rate. The increasing frequency of these malignancies has marked the need for adopting effective treatment plan coupled with better and site-specific delivery options for the desired therapeutic agent's availability at the affected site. The concurrent delivery approaches to cancerous tissues are under constant challenge and, as a result, are evolving and gaining advancements in terms of delivery modes, therapeutic agents and site-specificity of the therapeutics delivery. The lipid-based liposomal drug delivery is an attractive and emerging option, and which is meticulously shaping up beyond a threshold level to a promising, and viable route for the effective delivery of therapeutic agents and other required injuctions to the skin cancer. An update on liposomal delivery of chemotherapeutic agents, natural-origin compounds, photosensitizer, and DNA repair enzymes as well as other desirable and typical delivery modes employed in drug delivery and in the treatment of skin cancers is discussed in details. Moreover, liposomal delivery of nucleic acid-based therapeutics, i.e., small interfering RNA (siRNA), mRNA therapy, and RGD-linked liposomes are among the other promising novel technology under constant development. The current clinical applicability, viable clinical plans, future prospects including transport feasibility of delivery vesicles and imaging techniques in conjunction with the therapeutic agents is also discussed. The ongoing innovations in liposomal drug delivery technology for skin cancers hold promise for further development of the methodology for better, more effective and site-specific delivery as part of the better treatment plan by ensuring faster drug transport, better and full payload delivery with enough and required concentration of the dose. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Biomimetics in drug delivery systems: A critical review.

    PubMed

    Sheikhpour, Mojgan; Barani, Leila; Kasaeian, Alibakhsh

    2017-03-18

    Today, the advanced drug delivery systems have been focused on targeted drug delivery fields. The novel drug delivery is involved with the improvement of the capacity of drug loading in drug carriers, cellular uptake of drug carriers, and the sustained release of drugs within target cells. In this review, six groups of therapeutic drug carriers including biomimetic hydrogels, biomimetic micelles, biomimetic liposomes, biomimetic dendrimers, biomimetic polymeric carriers and biomimetic nanostructures, are studied. The subject takes advantage of the biomimetic methods of productions or the biomimetic techniques for the surface modifications, similar to what accrues in natural cells. Moreover, the effects of these biomimetic approaches for promoting the drug efficiency in targeted drug delivery are visible. The study demonstrates that the fabrication of biomimetic nanocomposite drug carriers could noticeably promote the efficiency of drugs in targeted drug delivery systems.

  20. 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

  1. Viruses as nanomaterials for drug delivery.

    PubMed

    Lockney, Dustin; Franzen, Stefan; Lommel, Steven

    2011-01-01

    Virus delivery vectors are one among the many nanomaterials that are being developed as drug delivery materials. This chapter focuses on methods utilizing plant virus nanoparticles (PVNs) synthesized from the Red clover necrotic mosaic virus (RCNMV). A successful vector must be able to effectively carry and subsequently deliver a drug cargo to a specific target. In the case of the PVNs, we describe two types of ways cargo can be loaded within these structures: encapsidation and infusion. Several targeting approaches have been used for PVNs based on bioconjugate chemistry. Herein, examples of such approaches will be given that have been used for RCNMV as well as for other PVNs in the literature. Further, we describe characterization of PVNs, in vitro cell studies that can be used to test the efficacy of a targeting vector, and potential routes for animal administration.

  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. 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.

  4. 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

  5. Stable transfection of extrinsic Smac gene enhances apoptosis-inducing effects of chemotherapeutic drugs on gastric cancer cells

    PubMed Central

    Zheng, Li-Duan; Tong, Qiang-Song; Wang, Liang; Liu, Jun; Qian, Wei

    2005-01-01

    AIM: To explore the feasibility of enhancing apoptosis-inducing effects of chemotherapeutic drugs on human gastric cancer cells by stable transfection of extrinsic Smac gene. METHODS: After Smac gene was transferred into gastric cancer cell line MKN-45, subclone cells were obtained by persistent G418 selection. Cellular Smac gene expression was determined by RT-PCR and Western blotting. After treatment with mitomycin (MMC) as an apoptotic inducer, in vitro cell growth activities were investigated by trypan blue-staining method and MTT colorimetry. Cell apoptosis and its rates were determined by electronic microscopy, annexin V-FITC and propidium iodide staining flow cytometry. Cellular caspase-3 protein expression and its activities were assayed by Western blotting and colorimetry. RESULTS: When compared with MKN-45 cells, the selected subclone cell line MKN-45/Smac had significantly higher Smac mRNA (3.12±0.21 vs 0.82±0.14, t = 7.52, P<0.01) and protein levels (4.02±0.24 vs 0.98±0.11, t = 8.32, P<0.01). After treatment with 10 μg/mL MMC for 6-24 h, growth inhibition rate of MKN-45/Smac (15.8±1.2-54.8±2.9%) was significantly higher than that of MKN-45 (5.8±0.4- 24.0±1.5%, t = 6.42, P<0.01). Partial MKN-45/Smac cancer cells presented characteristic morphological changes of apoptosis under the electronic microscope with an apoptosis rate of 36.4±2.1%, which was significantly higher than that of MKN-45 (15.2±0.8%, t = 9.25, P<0.01). Compared with MKN-45, caspase-3 expression levels in MKN-45/Smac were improved significantly (3.39±0.42 vs 0.96±0.14, t = 8.63, P<0.01), while its activities were 3.25 times as many as those of MKN-45 (0.364±0.010 vs 0.112±0.007, t = 6.34, P<0.01). CONCLUSION: Stable transfection of extrinsic Smac gene and its over-expression in gastric cancer cell line can significantly enhance cellular caspase-3 expression and activities, ameliorate apoptosis-inducing effects of mitomycin C on cancer cells, which is a novel strategy to

  6. 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.

  7. Novel magnetic/ultrasound focusing system enhances nanoparticle drug delivery for glioma treatment

    PubMed Central

    Chen, Pin-Yuan; Liu, Hao-Li; Hua, Mu-Yi; Yang, Hung-Wei; Huang, Chiung-Yin; Chu, Po-Chun; Lyu, Lee-Ang; Tseng, I-Chou; Feng, Li-Ying; Tsai, Hong-Chieh; Chen, Shu-Mei; Lu, Yu-Jen; Wang, Jiun-Jie; Yen, Tzu-Chen; Ma, Yunn-Hwa; Wu, Tony; Chen, Jyh-Ping; Chuang, Jih-Ing; Shin, Jyh-Wei; Hsueh, Chuen; Wei, Kuo-Chen

    2010-01-01

    Malignant glioma is a common and severe primary brain tumor with a high recurrence rate and an extremely high mortality rate within 2 years of diagnosis, even when surgical, radiological, and chemotherapeutic interventions are applied. Intravenously administered drugs have limited use because of their adverse systemic effects and poor blood–brain barrier penetration. Here, we combine 2 methods to increase drug delivery to brain tumors. Focused ultrasound transiently permeabilizes the blood–brain barrier, increasing passive diffusion. Subsequent application of an external magnetic field then actively enhances localization of a chemotherapeutic agent immobilized on a novel magnetic nanoparticle. Combining these techniques significantly improved the delivery of 1,3-bis(2-chloroethyl)-1-nitrosourea to rodent gliomas. Furthermore, the physicochemical properties of the nanoparticles allowed their delivery to be monitored by magnetic resonance imaging (MRI). The resulting suppression of tumor progression without damaging the normal regions of the brain was verified by MRI and histological examination. This noninvasive, reversible technique promises to provide a more effective and tolerable means of tumor treatment, with lower therapeutic doses and concurrent clinical monitoring. PMID:20663792

  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. 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

  10. 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

    2015-11-05

    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.

  11. 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

  12. Targeted Delivery of Protein Drugs by Nanocarriers

    PubMed Central

    Solaro, Roberto; Chiellini, Federica; Battisti, Antonella

    2010-01-01

    Recent advances in biotechnology demonstrate that peptides and proteins are the basis of a new generation of drugs. However, the transportation of protein drugs in the body is limited by their high molecular weight, which prevents the crossing of tissue barriers, and by their short lifetime due to immuno response and enzymatic degradation. Moreover, the ability to selectively deliver drugs to target organs, tissues or cells is a major challenge in the treatment of several human diseases, including cancer. Indeed, targeted delivery can be much more efficient than systemic application, while improving bioavailability and limiting undesirable side effects. This review describes how the use of targeted nanocarriers such as nanoparticles and liposomes can improve the pharmacokinetic properties of protein drugs, thus increasing their safety and maximizing the therapeutic effect.

  13. 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.

  14. The proteasome of malaria parasites: A multi-stage drug target for chemotherapeutic intervention?

    PubMed Central

    Aminake, Makoah Nigel; Arndt, Hans-Dieter; Pradel, Gabriele

    2012-01-01

    The ubiquitin/proteasome system serves as a regulated protein degradation pathway in eukaryotes, and is involved in many cellular processes featuring high protein turnover rates, such as cell cycle control, stress response and signal transduction. In malaria parasites, protein quality control is potentially important because of the high replication rate and the rapid transformations of the parasite during life cycle progression. The proteasome is the core of the degradation pathway, and is a major proteolytic complex responsible for the degradation and recycling of non-functional ubiquitinated proteins. Annotation of the genome for Plasmodium falciparum, the causative agent of malaria tropica, revealed proteins with similarity to human 26S proteasome subunits. In addition, a bacterial ClpQ/hslV threonine peptidase-like protein was identified. In recent years several independent studies indicated an essential function of the parasite proteasome for the liver, blood and transmission stages. In this review, we compile evidence for protein recycling in Plasmodium parasites and discuss the role of the 26S proteasome as a prospective multi-stage target for antimalarial drug discovery programs. PMID:24533266

  15. Block copolymer micelles: preparation, characterization and application in drug delivery.

    PubMed

    Gaucher, Geneviève; Dufresne, Marie-Hélène; Sant, Vinayak P; Kang, Ning; Maysinger, Dusica; Leroux, Jean-Christophe

    2005-12-05

    Block copolymer micelles are generally formed by the self-assembly of either amphiphilic or oppositely charged copolymers in aqueous medium. The hydrophilic and hydrophobic blocks form the corona and the core of the micelles, respectively. The presence of a nonionic water-soluble shell as well as the scale (10-100 nm) of polymeric micelles are expected to restrict their uptake by the mononuclear phagocyte system and allow for passive targeting of cancerous or inflamed tissues through the enhanced permeation and retention effect. Research in the field has been increasingly focused on achieving enhanced stability of the micellar assembly, prolonged circulation times and controlled release of the drug for optimal targeting. With that in mind, our group has developed a range of block copolymers for various applications, including amphiphilic micelles for passive targeting of chemotherapeutic agents and environment-sensitive micelles for the oral delivery of poorly bioavailable compounds. Here, we propose to review the innovations in block copolymer synthesis, polymeric micelle preparation and characterization, as well as the relevance of these developments to the field of biomedical research.

  16. [The effect of Bcl-2 gene silencing on the sensitivity of cell line A549 to chemotherapeutic drugs].

    PubMed

    Wang, Jiao-qi; Du, Zhen-wu; Gao, Xian-fei; Wu, Mei; Zhang, Yu-cheng; Pan, Ying; Wang, Qian; Zhang, Gui-zhen

    2013-03-01

    To investigate the effects of miRNA-mediated down-regulation of the Bcl-2 gene on the chemotherapeutic sensitivities and mRNA transcriptions of sensitivity associated genes in human lung adenocarcinoma cell line A549 cells, and therefore to provide experimental data for improving the chemotherapeutic effects on non-small cell lung cancer (NSCLC). The miRNA recombinant plasmid targeting to human Bcl-2 gene was designed, synthesized and stably transferred into A549 cells by lipofectin technique as the experiment group. The transcription of Bcl-2 mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR) by agarose gel electrophoresis, real-time PCR, and the protein level of Bcl-2 was measured by Western blot to confirm the function of miRNA plasmid. The cell proliferation was examined by methyl thiazolyl tetrazolium (MTT) assay. Cell cycle was measured by flow cytometry. Drug sensitivities of A549 cells to etoposide, 5-fluorouracil, cisplatin, adriamycin, vincristine, paclitaxel and navelbine were analyzed by MTT assay. The mRNA expressions of excision repair cross-complementing gene 1 (ERCC1), thymidylate synthase (TYMS), Class III β-tubulin, topoisomerase 2 alpha (TOP2α) genes were detected by RT-PCR and real-time PCR. The recombinant miRNA plasmid was successfully synthesized and stably transferred into A549 cells. The transcription of Bcl-2 mRNA dramatically decreased by 98.1% in the experiment group (RQ = 0.002 ± 0.001) compared to that in the negative control group (RQ = 0.104 ± 0.003) by real-time PCR (t = 98.70, P < 0.05); and the protein level of Bcl-2 in the experiment group decreased by 57.6% by Western blot (t = 7.66, P < 0.05). The cell cycle profile showed that the low expression of Bcl-2 gene led to A549 cell cycle arrest at G1-phase. The results of MTT showed that the growth of A549 cells in the experiment group was markedly inhibited. The sensitivities of A549 cells to etoposide, cisplatin, paclitaxel, and navelbine were

  17. 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

  18. 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

  19. Iontophoretic drug delivery across the nail.

    PubMed

    Delgado-Charro, Maria Begoña

    2012-01-01

    Topical drug delivery to treat nail diseases such as onychomycosis and psoriasis is receiving increasing attention. Topical nail delivery is challenged by the complicated structure of the nail and the low permeability of most drugs across the nail plate. Considerable effort has been directed at developing methods to promote drug permeation across the nail plate. Iontophoresis efficiently enhances molecular transport across the skin and the eye and is now being tested for its potential in ungual delivery. This review covers the basic mechanisms of transport (electro-osmosis and -migration) and their relative contribution to nail iontophoresis as well as the key factors governing nail permselectivity and ionic transport numbers. Methodological issues concerning research in this area are summarized. The data available in vivo on nail iontophoresis of terbinafine specifically are reviewed in separate sections. Our understanding of nail iontophoresis has improved considerably since 2007; most decisively, the feasibility of nail iontophoresis in vivo has been clearly demonstrated. Future work is required to establish the adequate implementation of the technique so that its clinical efficacy to treat onychomycosis and nail psoriasis can be unequivocally determined.

  20. 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.

  1. A model of axonal transport drug delivery

    NASA Astrophysics Data System (ADS)

    Kuznetsov, Andrey V.

    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.

  2. 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

  3. Molecular effects of chemotherapeutic drugs and their modulation by antioxidants in the testis.

    PubMed

    Narayana, Kilarkaje; Al-Bader, Maie; Mousa, Alyaa; Khan, Khalid M

    2012-01-15

    Cisplatin-based chemotherapy regimens are preferred in the treatment of a variety of cancers. The present study investigated early cumulative molecular effects of therapeutic dose-levels of bleomycin, etoposide and cisplatin (BEP) in the testis and their modulation by an antioxidant cocktail (AO). Adult male Sprague-Dawley rats (N=7/group [G]) were treated with BEP as follows: G1 - control; G2 - AO (α-tocopherol [100 mg/kg], l-ascorbic acid [50 mg/kg], Zn [40 mg/l] and Se [100 μg/l]); G3 - B, 1.5 mg/kg on day 2; E, 15 mg/kg and P, 3 mg/kg for 4 days, and G4 - similar to G3 but also treated with AO for 4 days. In G3, the testis weight, sperm count and motility, and activities of enzymatic antioxidants decreased and lipid peroxidation increased compared to that in G1 (P<0.05). Seminiferous epithelial sloughing and degeneration were observed. In G3, mRNA levels of p53, Bcl-2 and Bax were unaltered but protein expression of p53 and Bax was up-regulated and that of Bcl-2 was down-regulated (P<0.05). These changes led to an increase in terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) positive germ cells indicating cell death (P<0.05). The AO recovered the BEP-induced molecular alterations to control levels. The mechanism of BEP-induced early testicular damage involves the initiation of oxidative stress, up-regulation of pro-apoptotic proteins and induction of cell death. Further, the induced testicular structural changes are negligible and less than those observed in single drug exposure studies reported in literature. The AO significantly ameliorates the BEP-induced pathogenesis of testicular damage suggesting its potential therapeutic uses.

  4. Drug Delivery to CNS: Challenges and Opportunities with Emphasis on Biomaterials Based Drug Delivery Strategies.

    PubMed

    Khambhla, Ekta; Shah, Viral; Baviskar, Kalpesh

    2016-01-01

    The current epoch has witnessed a lifestyle impregnated with stress, which is a major cause of several neurological disorders. High morbidity and mortality rate due to neurological diseases and disorders have generated a huge social impact. Despite voluminous research, patients suffering from fatal and/or debilitating CNS diseases such as brain tumors, HIV, encephalopathy, Alzheimer's, epilepsy, Parkinson's, migraine and multiple sclerosis outnumbered those suffering from systemic cancer or heart diseases. The brain being a highly sensitive neuronal organ, has evolved with vasculature barriers, which regulates the efflux and influx of substances to CNS. Treatment of CNS diseases/disorders is challenging because of physiologic, metabolic and biochemical obstacles created by these barriers which comprise mainly of BBB and BCFB. The inability of achieving therapeutically active concentration has become the bottleneck level difficulty, hampering the therapeutic efficiency of several promising drug candidates for CNS related disorders. Parallel maturation of an effective CNS drug delivery strategy with CNS drug discovery is the need of the hour. Recently, the focus of the pharmaceutical community has aggravated in the direction of developing novel and more efficient drug delivery systems, giving the potential of more effective and safer CNS therapies. The present review outlines several hurdles in drug delivery to the CNS along with ideal physicochemical properties desired in drug substance/formulation for CNS delivery. The review also focuses on different conventional and novel strategies for drug delivery to the CNS. The article also assesses and emphasizes on possible benefits of biomaterial based formulations for drug delivery to the CNS.

  5. Advances in Bone-targeted Drug Delivery Systems for Neoadjuvant Chemotherapy for Osteosarcoma.

    PubMed

    Li, Cheng-Jun; Liu, Xiao-Zhou; Zhang, Lei; Chen, Long-Bang; Shi, Xin; Wu, Su-Jia; Zhao, Jian-Ning

    2016-05-01

    Targeted therapy for osteosarcoma includes organ, cell and molecular biological targeting; of these, organ targeting is the most mature. Bone-targeted drug delivery systems are used to concentrate chemotherapeutic drugs in bone tissues, thus potentially resolving the problem of reaching the desired foci and minimizing the toxicity and adverse effects of neoadjuvant chemotherapy. Some progress has been made in bone-targeted drug delivery systems for treatment of osteosarcoma; however, most are still at an experimental stage and there is a long transitional period to clinical application. Therefore, determining how to combine new, polymolecular and multi-pathway targets is an important research aspect of designing new bone-targeted drug delivery systems in future studies. The purpose of this article was to review the status of research on targeted therapy for osteosarcoma and to summarize the progress made thus far in developing bone-targeted drug delivery systems for neoadjuvant chemotherapy for osteosarcoma with the aim of providing new ideas for highly effective therapeutic protocols with low toxicity for patients with osteosarcoma. © 2016 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

  6. 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

  7. 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.

  8. Phospholipid nanodisc engineering for drug delivery systems.

    PubMed

    Murakami, Tatsuya

    2012-06-01

    Biocompatible mesoscale nanoparticles (5-100 nm in diameter) are attractive tools for drug delivery. Among them are several types of liposomes and polymer micelles already in clinical trial or use. Generally, biocompatibility of such particles is achieved by coating them with polyethylene glycol (PEG). Without PEG coating, particles are quickly trapped in the reticuloendothelial system when intravenously administered. However, recent studies have revealed several potential problems with PEG coating, including antigenicity and restriction of cellular uptake. This has motivated the development of alternative drug and gene delivery vehicles, including chemically and genetically engineered high-density lipoprotein (HDL)-like nanodiscs or "bicelles". HDL is a naturally occurring mesoscale nanoparticle that normally ferries cholesterol around in the body. Its initial "nascent" form is thought to be a simple 10 nm disc of phospholipids in a bilayer, and can be easily synthesized in vitro by mixing recombinant apoA-I proteins with various phospholipids. In this review, the use of synthetic HDL-like phospholipid nanodiscs as biocompatible drug carriers is summarized, focussing on manufacturing, size-control, drug loading and cell targeting. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. 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.

  10. Radionuclide imaging of liposomal drug delivery.

    PubMed

    van der Geest, Tessa; Laverman, Peter; Metselaar, Josbert M; Storm, Gert; Boerman, Otto C

    2016-09-01

    Ever since their discovery, liposomes have been radiolabeled to monitor their fate in vivo. Despite extensive preclinical studies, only a limited number of radiolabeled liposomal formulations have been examined in patients. Since they can play a crucial role in patient management, it is of importance to enable translation of radiolabeled liposomes into the clinic. Liposomes have demonstrated substantial advantages as drug delivery systems and can be efficiently radiolabeled. Potentially, radiolabeled drug-loaded liposomes form an elegant theranostic system, which can be tracked in vivo using single-photon emission computed tomography (SPECT) or positron emission tomography (PET) imaging. In this review, we discuss important aspects of liposomal research with a focus on the use of radiolabeled liposomes and their potential role in drug delivery and monitoring therapeutic effects. Radiolabeled drug-loaded liposomes have been poorly investigated in patients and no radiolabeled liposomes have been approved for use in clinical practice. Evaluation of the risks, pharmacokinetics, pharmacodynamics and toxicity is necessary to meet pharmaceutical and commercial requirements. It remains to be demonstrated whether the results found in animal studies translate to humans before radiolabeled liposomes can be implemented into clinical practice.

  11. 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.

  12. 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

  13. Lipid-Based Drug Delivery Systems in Cancer Therapy: What Is Available and What Is Yet to Come

    PubMed Central

    Yingchoncharoen, Phatsapong; Kalinowski, Danuta S.

    2016-01-01

    Cancer is a leading cause of death in many countries around the world. However, the efficacy of current standard treatments for a variety of cancers is suboptimal. First, most cancer treatments lack specificity, meaning that these treatments affect both cancer cells and their normal counterparts. Second, many anticancer agents are highly toxic, and thus, limit their use in treatment. Third, a number of cytotoxic chemotherapeutics are highly hydrophobic, which limits their utility in cancer therapy. Finally, many chemotherapeutic agents exhibit short half-lives that curtail their efficacy. As a result of these deficiencies, many current treatments lead to side effects, noncompliance, and patient inconvenience due to difficulties in administration. However, the application of nanotechnology has led to the development of effective nanosized drug delivery systems known commonly as nanoparticles. Among these delivery systems, lipid-based nanoparticles, particularly liposomes, have shown to be quite effective at exhibiting the ability to: 1) improve the selectivity of cancer chemotherapeutic agents; 2) lower the cytotoxicity of anticancer drugs to normal tissues, and thus, reduce their toxic side effects; 3) increase the solubility of hydrophobic drugs; and 4) offer a prolonged and controlled release of agents. This review will discuss the current state of lipid-based nanoparticle research, including the development of liposomes for cancer therapy, different strategies for tumor targeting, liposomal formulation of various anticancer drugs that are commercially available, recent progress in liposome technology for the treatment of cancer, and the next generation of lipid-based nanoparticles. PMID:27363439

  14. 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.

  15. 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

  16. Multiscale benchmarking of drug delivery vectors.

    PubMed

    Summers, Huw D; Ware, Matthew J; Majithia, Ravish; Meissner, Kenith E; Godin, Biana; Rees, Paul

    2016-10-01

    Cross-system comparisons of drug delivery vectors are essential to ensure optimal design. An in-vitro experimental protocol is presented that separates the role of the delivery vector from that of its cargo in determining the cell response, thus allowing quantitative comparison of different systems. The technique is validated through benchmarking of the dose-response of human fibroblast cells exposed to the cationic molecule, polyethylene imine (PEI); delivered as a free molecule and as a cargo on the surface of CdSe nanoparticles and Silica microparticles. The exposure metrics are converted to a delivered dose with the transport properties of the different scale systems characterized by a delivery time, τ. The benchmarking highlights an agglomeration of the free PEI molecules into micron sized clusters and identifies the metric determining cell death as the total number of PEI molecules presented to cells, determined by the delivery vector dose and the surface density of the cargo. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Mild oxidative stress induces S-glutathionylation of STAT3 and enhances chemosensitivity of tumoural cells to chemotherapeutic drugs.

    PubMed

    Butturini, Elena; Carcereri de Prati, Alessandra; Chiavegato, Giulia; Rigo, Antonella; Cavalieri, Elisabetta; Darra, Elena; Mariotto, Sofia

    2013-12-01

    STAT3 is a transcription factor constitutively activated in a variety of cancers that has a critical role in the inhibition of apoptosis and induction of chemoresistance. Inhibition of the STAT3 signaling pathway suppresses cell survival signals and leads to apoptosis in cancer cells, suggesting that direct inhibition of STAT3 function is a viable therapeutic approach. Herein, we identify the naturally occurring sesquiterpene lactone cynaropicrin as a potent inhibitor of both IL-6-inducible and constitutive STAT3 activation (IC50=12 μM). Cynaropicrin, which contains an α-β-unsaturated carbonyl moiety and acts as potent Michael reaction acceptor, induces a rapid drop in intracellular glutathione (GSH) concentration, thereby triggering S-glutathionylation of STAT3. Furthermore, glutathione ethylene ester, the cell permeable form of GSH, reverts the inhibitory action of cynaropicrin on STAT3 tyrosine phosphorylation. These findings suggest that this sesquiterpene lactone is able to induce redox-dependent post-translational modification of cysteine residues of STAT3 protein to regulate its function. STAT3 inhibition led to the suppression of two anti-apoptotic genes, Bcl-2 and survivin, in DU145 cells that constitutively express active STAT3. This event may be responsible for the decline in cell viability after cynaropicrin treatment. As revealed by PI/annexin-V staining, PARP cleavage, and DNA ladder formation, cynaropicrin cytotoxicity is mediated by apoptosis. Finally, cynaropicrin displayed a slight to strong synergism with two well-established chemotherapeutic drugs, cisplatin and docetaxel. Taken together our studies suggest that cynaropicrin suppresses the STAT3 pathway, leading to the down-regulation of STAT3-dependent gene expression and chemosensitization of tumour cells to chemotherapy. © 2013 Elsevier Inc. All rights reserved.

  18. 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

  19. 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.

  20. 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.

  1. Polymers in the Co-delivery of siRNA and Anticancer Drugs for the Treatment of Drug-resistant Cancers.

    PubMed

    Sun, Haotian; Yarovoy, Iven; Capeling, Meghan; Cheng, Chong

    2017-04-01

    Recently, co-delivery of siRNA and anticancer drugs has drawn much attention in the treatment of drug-resistant cancers. Drug resistance is exhibited by cancer cells, which limits the efficacy of chemotherapy. When siRNA and anticancer drugs are delivered into cancer cells simultaneously, the siRNA is expected to silence the genes related to drug resistance, decreasing the drug efflux pumps and activating the cell's apoptosis pathways. In a timeframe following the release of siRNA, the accumulation of the co-delivered anti-cancer drug inside of the cancer cells will increase, resulting in promoted chemotherapeutic effects. Several classes of nanocarriers have been designed based on polymers for co-delivery, including surface-modified polymer nanoparticles (NPs), polymer micelles, dendrimers, polymer nanocapsules, polymer-modified liposomes, and polymer-modified silica and gold NPs. Compared with separate delivery, co-delivery showed significant advantages in the treatment of drug-resistant cancers. This review focuses on polymers in the co-delivery of siRNA and anticancer drugs, and summarizes key advances in the recent several years.

  2. Ultrasound Molecular Imaging and Drug Delivery.

    PubMed

    Caskey, Charles F

    2017-03-02

    Ultrasound is a rapidly advancing field with many emerging diagnostic and therapeutic applications. For diagnostics, new vascular targets are routinely identified and mature technologies are being translated to humans, while other recent innovations may bring about the creation of acoustic reporter genes and micron-scale resolution with ultrasound. As a cancer therapy, ultrasound is being explored as an adjuvant to immune therapies and to deliver acoustically or thermally active drugs to tumor regions. Ultrasound-enhanced delivery across the blood brain barrier (BBB) could potentially be very impactful for brain cancers and neurodegenerative diseases where the BBB often impedes the delivery of therapeutic molecules. In this minireview, we provide an overview of these topics in the field of ultrasound that are especially relevant to the interests of World Molecular Imaging Society.

  3. Drug transport and drug delivery--the Midnight Sun meeting.

    PubMed

    Uchegbu, Ijeoma F

    2004-08-01

    The Midnight Sun Meeting on Drug Transport and Drug Delivery was held on the island of Tromso in northern Norway, where the sun does not set for 2 months during the summer. The meeting was hosted by the University of Tromso's newly established Institute of Pharmacy and the Controlled Release Society (Nordic Chapter). The meeting, attended by approximately 80 delegates from across Europe, showcased recent advances in drug transport through biological barriers, solid-state pharmaceuticals and particulate drug delivery systems. This report will focus on the particulate and solid-state pharmaceuticals sessions, in which lectures were given to demonstrate the benefits in cognitive function associated with omega-3 fish oils, the increase in drug release rates observed on the processing-induced deformation of tablet granules, and the size of polymeric particulates being directly and linearly related to the molecular weight of a polymer. The meeting was held as a single-session event, giving delegates the opportunity to attend all presentations. There was a small poster and exhibitor display, and the meeting attracted sponsorship from a number of companies, namely Polypure AS, Weifa AS, ProBioNeutraceuticals AS, Lipoid GmbH, Clavis Pharma AS and Thermometric AB.

  4. In Situ Forming Polymeric Drug Delivery Systems

    PubMed Central

    Madan, M.; Bajaj, A.; Lewis, S.; Udupa, N.; Baig, J. A.

    2009-01-01

    In situ forming polymeric formulations are drug delivery systems that are in sol form before administration in the body, but once administered, undergo gelation in situ, to form a gel. The formation of gels depends on factors like temperature modulation, pH change, presence of ions and ultra violet irradiation, from which the drug gets released in a sustained and controlled manner. Various polymers that are used for the formulation of in situ gels include gellan gum, alginic acid, xyloglucan, pectin, chitosan, poly(DL-lactic acid), poly(DL-lactide-co-glycolide) and poly-caprolactone. The choice of solvents like water, dimethylsulphoxide, N-methyl pyrrolidone, triacetin and 2-pyrrolidone for these formulations depends on the solubility of polymer used. Mainly in situ gels are administered by oral, ocular, rectal, vaginal, injectable and intraperitoneal routes. The in situ gel forming polymeric formulations offer several advantages like sustained and prolonged action in comparison to conventional drug delivery systems. The article presents a detailed review of these types of polymeric systems, their evaluation, advancements and their commercial formulations. From a manufacturing point of view, the production of such devices is less complex and thus lowers the investment and manufacturing cost. PMID:20490289

  5. Transdermal patch drug delivery interactions with exercise.

    PubMed

    Lenz, Thomas L; Gillespie, Nicole

    2011-03-01

    Transdermal drug delivery systems, such as the transdermal patch, continue to be a popular and convenient way to administer medications. There are currently several medications that use a transdermal patch drug delivery system. This article describes the potential untoward side effects of increased drug absorption through the use of a transdermal patch in individuals who exercise or participate in sporting events. Four studies have been reported that demonstrate a significant increase in the plasma concentration of nitroglycerin when individuals exercise compared with rest. Likewise, several case reports and two studies have been conducted that demonstrate nicotine toxicity and increased plasma nicotine while wearing a nicotine patch in individuals who exercise or participate in sporting events compared with rest. Healthcare providers, trainers and coaches should be aware of proper transdermal patch use, especially while exercising, in order to provide needed information to their respective patients and athletes to avoid potential untoward side effects. Particular caution should be given to individuals who participate in an extreme sporting event of long duration. Further research that includes more medications is needed in this area.

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

    PubMed

    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.

  7. 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

  8. [Studies on market of drug delivery system product and drug delivery system of compound Chinese medicine].

    PubMed

    Feng, Yi; Xu, De-Sheng; Hong, Yan-Long; Zhang, Ning; Ma, Yue-Ming

    2006-10-01

    Based on the progress in the world market of drug delivery system (DDS) product and the research profile of DDS of compound Chinese Medicine, The article puts forward a new method of studies on DDS of compound Chinese Medicine. It is expected that the theory of compatibility of compound Chinese Medicine can be shown and its role can be exerted to the largest extent with the application of pharmaceutics technology to change the mode of drug delivery of activated components of compound Chinese Medicine.

  9. 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

  10. Recent advances of controlled drug delivery using microfluidic platforms.

    PubMed

    Sanjay, Sharma T; Zhou, Wan; Dou, Maowei; Tavakoli, Hamed; Ma, Lei; Xu, Feng; Li, XiuJun

    2017-09-15

    Conventional systematically-administered drugs distribute evenly throughout the body, get degraded and excreted rapidly while crossing many biological barriers, leaving minimum amounts of the drugs at pathological sites. Controlled drug delivery aims to deliver drugs to the target sites at desired rates and time, thus enhancing the drug efficacy, pharmacokinetics, and bioavailability while maintaining minimal side effects. Due to a number of unique advantages of the recent microfluidic lab-on-a-chip technology, microfluidic lab-on-a-chip has provided unprecedented opportunities for controlled drug delivery. Drugs can be efficiently delivered to the target sites at desired rates in a well-controlled manner by microfluidic platforms via integration, implantation, localization, automation, and precise control of various microdevice parameters. These features accordingly make reproducible, on-demand, and tunable drug delivery become feasible. On-demand self-tuning dynamic drug delivery systems have shown great potential for personalized drug delivery. This review presents an overview of recent advances in controlled drug delivery using microfluidic platforms. The review first briefly introduces microfabrication techniques of microfluidic platforms, followed by detailed descriptions of numerous microfluidic drug delivery systems that have significantly advanced the field of controlled drug delivery. Those microfluidic systems can be separated into four major categories, namely drug carrier-free micro-reservoir-based drug delivery systems, highly integrated carrier-free microfluidic lab-on-a-chip systems, drug carrier-integrated microfluidic systems, and microneedles. Microneedles can be further categorized into five different types, i.e. solid, porous, hollow, coated, and biodegradable microneedles, for controlled transdermal drug delivery. At the end, we discuss current limitations and future prospects of microfluidic platforms for controlled drug delivery. Copyright

  11. 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

  12. 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

  13. 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

  14. Biopolymers as transdermal drug delivery systems in dermatology therapy.

    PubMed

    Basavaraj, K H; Johnsy, George; Navya, M A; Rashmi, R; Siddaramaiah

    2010-01-01

    The skin is considered a complex organ for drug delivery because of its structure. Drug delivery systems are designed for the controlled release of drugs through the skin into the systemic circulation, maintaining consistent efficacy and reducing the dose of the drugs and their related side effects. Transdermal drug delivery represents one of the most rapidly advancing areas of novel drug delivery. The excellent impervious nature of the skin is the greatest challenge that must be overcome for successful drug delivery. Today, polymers have been proven to be successful for long-term drug delivery applications as no single polymer can satisfy all of the requirements. Biopolymers in the field of dermal application are rare and the mechanisms that affect skin absorption are almost unknown. Biopolymers are widely used as drug delivery systems, but as such the use of biopolymers as drug delivery systems in dermatologic therapy is still in progress. Commonly used biopolymers include hydrocolloids, alginates, hydrogels, polyurethane, collagen, poly(lactic-co-glycolic acid), chitosan, proteins and peptides, pectin, siRNAs, and hyaluronic acid. These new and exciting methods for drug delivery are already increasing the number and quality of dermal and transdermal therapies. This article reviews current research on biopolymers and focuses on their potential as drug carriers, particularly in relation to the dermatologic aspects of their use.

  15. Breast Cancer-Targeted Nuclear Drug Delivery Overcoming Drug Resistance for Breast Cancer Chemotherapy

    DTIC Science & Technology

    2013-09-01

    degradable dendrimers and its applications for drug delivery .............................................. 23 3.1 Dendrimer design and synthesis...drug delivery .......................................................... 26 3.3 Dendrimer /lipid nanoassembly as “cluster bomb” for cascade tumor...degradable dendrimers and applied such dendrimers to formulate novel drug delivery systems to improve the limited penetration of anti-cancer drugs within

  16. Light activated liposomes: Functionality and prospects in ocular drug delivery.

    PubMed

    Lajunen, Tatu; Nurmi, Riikka; Kontturi, Leena; Viitala, Lauri; Yliperttula, Marjo; Murtomäki, Lasse; Urtti, Arto

    2016-12-28

    Ocular drug delivery, especially to the retina and choroid, is a major challenge in drug development. Liposome technology may be useful in ophthalmology in enabling new routes of delivery, prolongation of drug action and intracellular drug delivery, but drug release from the liposomes should be controlled. For that purpose, light activation may be an approach to release drug at specified time and site in the eye. Technical advances have been made in the field of light activated drug release, particularly indocyanine green loaded liposomes are a promising approach with safe materials and effective light triggered release of small and large molecules. This review discusses the liposomal drug delivery with light activated systems in the context of ophthalmic drug delivery challenges.

  17. 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.

  18. The Research Progress of Targeted Drug Delivery Systems

    NASA Astrophysics Data System (ADS)

    Zhan, Jiayin; Ting, Xizi Liang; Zhu, Junjie

    2017-06-01

    Targeted drug delivery system (DDS) means to selectively transport drugs to targeted tissues, organs, and cells through a variety of drugs carrier. It is usually designed to improve the pharmacological and therapeutic properties of conventional drugs and to overcome problems such as limited solubility, drug aggregation, poor bio distribution and lack of selectivity, controlling drug release carrier and to reduce normal tissue damage. With the characteristics of nontoxic and biodegradable, it can increase the retention of drug in lesion site and the permeability, improve the concentration of the drug in lesion site. at present, there are some kinds of DDS using at test phase, such as slow controlled release drug delivery system, targeted drug delivery systems, transdermal drug delivery system, adhesion dosing system and so on. This paper makes a review for DDS.

  19. Convection-enhanced drug delivery for gliomas

    PubMed Central

    Healy, Andrew T.; Vogelbaum, Michael A.

    2015-01-01

    In spite of aggressive multi-modality treatments, patients diagnosed with anaplastic astrocytoma and glioblastoma continue to display poor median survival. The success of our current conventional and targeted chemotherapies are largely hindered by systemic- and neurotoxicity, as well as poor central nervous system (CNS) penetration. Interstitial drug administration via convection-enhanced delivery (CED) is an alternative that potentially overcomes systemic toxicities and CNS delivery issues by directly bypassing the blood–brain barrier (BBB). This novel approach not only allows for directed administration, but also allows for newer, tumor-selective agents, which would normally be excluded from the CNS due to molecular size alone. To date, randomized trials of CED therapy have yet to definitely show survival advantage as compared with today's standard of care, however, early studies appear to have been limited by “first generation” delivery techniques. Taking into consideration lessons learned from early trials along with decades of research, newer CED technologies and therapeutic agents are emerging, which are reviewed herein. PMID:25722934

  20. 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

  1. Nanoparticles: a boon to drug delivery, therapeutics, diagnostics and imaging.

    PubMed

    Parveen, Suphiya; Misra, Ranjita; Sahoo, Sanjeeb K

    2012-02-01

    Drug delivery is an interdisciplinary and independent field of research and is gaining the attention of pharmaceutical researchers, medical doctors and industry. A safe and targeted drug delivery could improve the performance of some classic medicines already on the market, and moreover, will have implications for the development and success of new therapeutic strategies such as anticancer drug delivery, peptide and protein delivery and gene therapy. In the last decade, several drug-delivery technologies have emerged and a fascinating part of this field is the development of nanoscale drug delivery devices. Nanoparticles (NPs) have been developed as an important strategy to deliver conventional drugs, recombinant proteins, vaccines and more recently, nucleotides. NPs and other colloidal drug-delivery systems modify the kinetics, body distribution and drug release of an associated drug. This review article focuses on the potential of nanotechnology in medicine and discusses different nanoparticulate drug-delivery systems including polymeric NPs, ceramic NPs, magnetic NPs, polymeric micelles and dendrimers as well as their applications in therapeutics, diagnostics and imaging. This comprehensive review focuses on different nanoparticulate drug-delivery systems including polymeric NPs, ceramic NPs, magnetic NPs, polymeric micelles and dendrimers as well as their applications in therapeutics, diagnostics and imaging. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. 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.

  3. Importance of novel drug delivery systems in herbal medicines

    PubMed Central

    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

  4. 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.

  5. Mustard-inspired delivery shuttle for enhanced blood-brain barrier penetration and effective drug delivery in glioma therapy.

    PubMed

    Wang, Nan; Sun, Pei; Lv, Mingming; Tong, Gangsheng; Jin, Xin; Zhu, Xinyuan

    2017-04-05

    Effective penetration through the blood-brain barrier (BBB) remains a challenge for the treatment of many brain diseases. In this study, a small molecule, sinapic acid (SA), extracted from mustard, was selected as a novel bioinspired BBB-permeable ligand for efficient drug delivery in glioma treatment. SA was conjugated on the surface of zwitterionic polymer poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)-encapsulated bovine serum albumin (BSA)-based nanoparticles, yielding nBSA-SA. The PMPC shell serves as a protective layer to prolong the in vivo blood circulation time with a better chance to cross the BBB. Furthermore, temozolomide (TMZ), which can be loaded onto the nanoparticles via electrostatic interactions with acrylic acid (AA) to generate AA-nBSA-SA-TMZ, was applied as an excellent chemotherapeutic drug for glioma therapy. The obtained nanoparticles with a distinct size show great BBB permeability. Through the mechanism study, it was found that the cell internalization of the SA-conjugated nanoparticles is an energy-dependent process with only transient disruption of the BBB. The biological evaluation results unambiguously suggest that drug-loaded nanoparticles can lead to strong apoptosis on the tumor site and increase the median survival time of glioma-bearing mice. Overall, this novel BBB-permeable ligand SA paves the way for the delivery of cargo into the brain and provides a powerful nanoplatform for glioma therapy via intravenous administration.

  6. Light-sensitive intelligent drug delivery systems.

    PubMed

    Alvarez-Lorenzo, Carmen; Bromberg, Lev; Concheiro, Angel

    2009-01-01

    Drug delivery systems (DDS) capable of releasing an active molecule at the appropriate site and at a rate that adjusts in response to the progression of the disease or to certain functions/biorhythms of the organism are particularly appealing. Biocompatible materials sensitive to certain physiological variables or external physicochemical stimuli (intelligent materials) can be used for achieving this aim. Light-responsiveness is receiving increasing attention owing to the possibility of developing materials sensitive to innocuous electromagnetic radiation (mainly in the UV, visible and near-infrared range), which can be applied on demand at well delimited sites of the body. Some light-responsive DDS are of a single use (i.e. the light triggers an irreversible structural change that provokes the delivery of the entire dose) while others able to undergo reversible structural changes when cycles of light/dark are applied, behave as multi-switchable carriers (releasing the drug in a pulsatile manner). In this review, the mechanisms used to develop polymeric micelles, gels, liposomes and nanocomposites with light-sensitiveness are analyzed. Examples of the capability of some polymeric, lipidic and inorganic structures to regulate the release of small solutes and biomacromolecules are presented and the potential of light-sensitive carriers as functional components of intelligent DDS is discussed.

  7. 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.

  8. A microneedle roller for transdermal drug delivery.

    PubMed

    Park, Jung-Hwan; Choi, Seong-O; Seo, Soonmin; Choy, Young Bin; Prausnitz, Mark R

    2010-10-01

    Microneedle rollers have been used to treat large areas of skin for cosmetic purposes and to increase skin permeability for drug delivery. In this study, we introduce a polymer microneedle roller fabricated by inclined rotational UV lithography, replicated by micromolding hydrophobic polylactic acid and hydrophilic carboxy-methyl-cellulose. These microneedles created micron-scale holes in human and porcine cadaver skin that permitted entry of acetylsalicylic acid, Trypan blue and nanoparticles measuring 50nm and 200nm in diameter. The amount of acetylsalicylic acid delivered increased with the number of holes made in the skin and was 1-2 orders of magnitude greater than in untreated skin. Lateral diffusion in the skin between holes made by microneedles followed expected diffusional kinetics, with effective diffusivity values that were 23-160 times smaller than in water. Compared to inserting microneedles on a flat patch, the sequential insertion of microneedles row by row on a roller required less insertion force in full-thickness porcine skin. Overall, polymer microneedle rollers, prepared from replicated polymer films, offer a simple way to increase skin permeability for drug delivery.

  9. Challenges in modelling nanoparticles for drug delivery.

    PubMed

    Barnard, Amanda S

    2016-01-20

    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.

  10. 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.

  11. Adapalene microemulsion for transfollicular drug delivery.

    PubMed

    Bhatia, Gaurav; Zhou, Yingcong; Banga, Ajay K

    2013-08-01

    The aim of this study was to develop a microemulsion formulation of adapalene for transfollicular delivery. A pseudoternary phase diagram was developed for microemulsion consisting of oleic acid as oil phase, tween 20 as surfactant, Transcutol® as cosurfactant, and deionized water. Differential tape stripping and confocal laser scanning microscopy were performed to determine the penetration of microemulsion through hair follicles. Transmission electron microscopy, dynamic light scattering, polarizing light microscopy, and differential scanning calorimetry were performed to characterize the microstructures of microemulsion. The pH and viscosity of the microemulsions were also determined. Permeation studies were carried out in vitro on porcine ear skin over a period of 24 h using Franz diffusion cells. The drug penetration in the hair follicles increased from 0.109 ± 0.03 to 0.292 ± 0.094 μg, as the microstructure of microemulsion shifted from oil-in-water to bi-continuous, with increase in water content of microemulsion. Confocal laser scanning microscopy images suggested that hair follicles provided the path for transfollicular permeation of adapalene microemulsion. These results suggest that microemulsion penetrated through hair follicles and are promising for transfollicular drug delivery. Copyright © 2013 Wiley Periodicals, Inc.

  12. 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

  13. Diatomite silica nanoparticles for drug delivery.

    PubMed

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

    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. 87.85.J81.05.Rm; 61.46. + w.

  14. Polymeric micelles for acyclovir drug delivery.

    PubMed

    Sawdon, Alicia J; Peng, Ching-An

    2014-10-01

    Polymeric prodrug micelles for delivery of acyclovir (ACV) were synthesized. First, ACV was used directly to initiate ring-opening polymerization of ɛ-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. (1)H 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 200nm and the CMCs of ACV-PCL-MPEG and ACV-PCL-chitosan were 2.0mgL(-1) and 6.6mgL(-1), respectively. The drug release kinetics of ACV was investigated and cytotoxicity assay demonstrates that ACV-tagged polymeric micelles were non-toxic.

  15. 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

  16. 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. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  17. Antibody Drug Conjugate Bioinformatics: Drug Delivery through the Letterbox

    PubMed Central

    Vlachakis, Dimitrios

    2013-01-01

    Antibodies appear to be the first line of defence in the adaptive immune response of vertebrates and thereby are involved in a multitude of biochemical mechanisms, such as regulation of infection, autoimmunity, and cancer. It goes without saying that a full understanding of antibody function is required for the development of novel antibody-interacting drugs. These drugs are the Antibody Drug Conjugates (ADCs), which are a new type of targeted therapy, used for example for cancer. They consist of an antibody (or antibody fragment such as a single-chain variable fragment [scFv]) linked to a payload drug (often cytotoxic). Because of the targeting, the side effects should be lower and give a wider therapeutic window. Overall, the underlying principle of ADCs is to discern the delivery of a drug that is cytotoxic to a target that is cancerous, hoping to increase the antitumoural potency of the original drug by reducing adverse effects and side effects, such as toxicity of the cancer target. This is a pioneering field that employs state-of-the-art computational and molecular biology methods in the fight against cancer using ADCs. PMID:23853668

  18. Strategies of targeting oral drug delivery systems to the colon and their potential use for the treatment of colorectal cancer.

    PubMed

    Krishnaiah, Yellela S R; Khan, Mansoor A

    2012-01-01

    Colorectal cancer (CRC) is the third most common cause of cancer-related death in both men and women. Often, surgical intervention remains the choice in treating CRC. Traditional dosage forms used for treating CRC deliver drug to wanted as well as unwanted sites of drug action resulting in several adverse side effects. Targeted oral drug delivery systems are being investigated to target and deliver chemotherapeutic and chemopreventive agents directly to colon and rectum. Site-specific delivery of a drug to colon increases its concentration at the target site, and thus requires a lower dose with reduced incidence of side effects. The major obstacle to be overcome for successful targeting of drug to colon through oral route is that drug absorption/degradation must be avoided in stomach and small intestine before the dosage form reaches colon. The review includes discussion of physiological factors that must be considered when targeting drugs directly to colorectal region, an outline on drugs used for treatment and prevention of CRC, and a brief description of various types of colon-targeted oral drug delivery systems. The focus is on the assessment of various formulation approaches being investigated for oral colon-specific delivery of drugs used in the treatment and prevention of CRC.

  19. 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

  20. DNA origami as an in vivo drug delivery vehicle for cancer therapy.

    PubMed

    Zhang, Qian; Jiang, Qiao; Li, Na; Dai, Luru; Liu, Qing; Song, Linlin; Wang, Jinye; Li, Yaqian; Tian, Jie; Ding, Baoquan; Du, Yang

    2014-07-22

    Many chemotherapeutics used for cancer treatments encounter issues during delivery to tumors in vivo and may have high levels of systemic toxicity due to their nonspecific distribution. Various materials have been explored to fabricate nanoparticles as drug carriers to improve delivery efficiency. However, most of these materials suffer from multiple drawbacks, such as limited biocompatibility and inability to engineer spatially addressable surfaces that can be utilized for multifunctional activity. Here, we demonstrate that DNA origami possessed enhanced tumor passive targeting and long-lasting properties at the tumor region. Particularly, the triangle-shaped DNA origami exhibits optimal tumor passive targeting accumulation. The delivery of the known anticancer drug doxorubicin into tumors by self-assembled DNA origami nanostructures was performed, and this approach showed prominent therapeutic efficacy in vivo. The DNA origami carriers were prepared through the self-assembly of M13mp18 phage DNA and hundreds of complementary DNA helper strands; the doxorubicin was subsequently noncovalently intercalated into these nanostructures. After conducting fluorescence imaging and safety evaluation, the doxorubicin-containing DNA origami exhibited remarkable antitumor efficacy without observable systemic toxicity in nude mice bearing orthotopic breast tumors labeled with green fluorescent protein. Our results demonstrated the potential of DNA origami nanostructures as innovative platforms for the efficient and safe drug delivery of cancer therapeutics in vivo.

  1. Self-assembled Nanomaterials for Chemotherapeutic Applications

    NASA Astrophysics Data System (ADS)

    Shieh, Aileen

    The self-assembly of short designed peptides into functional nanostructures is becoming a growing interest in a wide range of fields from optoelectronic devices to nanobiotechnology. In the medical field, self-assembled peptides have especially attracted attention with several of its attractive features for applications in drug delivery, tissue regeneration, biological engineering as well as cosmetic industry and also the antibiotics field. We here describe the self-assembly of peptide conjugated with organic chromophore to successfully deliver sequence independent micro RNAs into human non-small cell lung cancer cell lines. The nanofiber used as the delivery vehicle is completely non-toxic and biodegradable, and exhibit enhanced permeability effect for targeting malignant tumors. The transfection efficiency with nanofiber as the delivery vehicle is comparable to that of the commercially available RNAiMAX lipofectamine while the toxicity is significantly lower. We also conjugated the peptide sequence with camptothecin (CPT) and observed the self-assembly of nanotubes for chemotherapeutic applications. The peptide scaffold is non-toxic and biodegradable, and drug loading of CPT is high, which minimizes the issue of systemic toxicity caused by extensive burden from the elimination of drug carriers. In addition, the peptide assembly drastically increases the solubility and stability of CPT under physiological conditions in vitro, while active CPT is gradually released from the peptide chain under the slight acidic tumor cell environment. Cytotoxicity results on human colorectal cancer cells and non-small cell lung cancer cell lines display promising anti-cancer properties compared to the parental CPT drug, which cannot be used clinically due to its poor solubility and lack of stability in physiological conditions. Moreover, the peptide sequence conjugated with 5-fluorouracil formed a hydrogel with promising topical chemotherapeutic applications that also display

  2. 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.

  3. Targeted drug delivery and enhanced intracellular release using functionalized liposomes

    NASA Astrophysics Data System (ADS)

    Garg, Ashish

    The ability to target cancer cells using an appropriate drug delivery system can significantly reduce the associated side effects from cancer therapies and can help in improving the overall quality of life, post cancer survival. Integrin alpha5beta1 is expressed on several types of cancer cells, including colon cancer and plays an important role in tumor growth and metastasis. Thus, the ability to target the integrin alpha 5beta1 using an appropriate drug delivery nano-vector can significantly help in inhibiting tumor growth and reducing tumor metastasis. The work in this thesis focuses on designing and optimizing, functionalized stealth liposomes (liposomes covered with polyethylene glycol (PEG)) that specifically target the integrin alpha5beta1. The PEG provides a steric barrier allowing the liposomes to circulate in the blood for longer duration and the functionalizing moiety, PR_b peptide specifically recognizes and binds to integrin alpha5beta1 expressing cells. The work demonstrates that by optimizing the amount of PEG and PR_b on the liposomal interface, nano-vectors can be engineered that bind to CT26.WT colon cancer cells in a specific manner and internalize through alpha 5beta1-mediated endocytosis. To further improve the efficacy of the system, PR_b functionalized pH-sensitive stealth liposomes that exhibit triggered release under mild acidic conditions present in endocytotic vesicles were designed. The study showed that PR_b functionalized pH-sensitive stealth liposomes, undergo destabilization under mildly acidic conditions and incorporation of the PR_b peptide does not significantly affect the pH-sensitivity of the liposomes. PR_b functionalized pH-sensitive stealth liposomes bind to CT26.WT colon carcinoma cells that express integrin alpha5beta 1, undergo cellular internalization, and release their load intracellularly in a short period of time as compared to other formulations. PR_b-targeted pH-sensitive stealth liposomes encapsulating 5

  4. 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

  5. Dendrimeric micelles for controlled drug release and targeted delivery

    PubMed Central

    Ambade, Ashootosh V.; Savariar, Elamprakash N.; Thayumanavan, S.

    2008-01-01

    This review highlights the developments in dendrimer-based micelles for drug delivery. Dendrimers, the perfectly branched monodisperse macromolecules, have certain structural advantages that make them attractive candidates as drug carriers for controlled release or targeted delivery. As polymeric micelle-based approaches precede the work in dendrimers, these are also discussed briefly. The review concludes with a perspective on possible applications of biaryl-based dendrimeric micelles that exhibit environment-dependent conformations, in drug delivery. PMID:16053329

  6. [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.

  7. Drug delivery from the oral cavity: focus on a novel mechatronic delivery device.

    PubMed

    Scholz, Oliver A; Wolff, Andy; Schumacher, Axel; Giannola, Libero I; Campisi, Giuseppina; Ciach, Tomasz; Velten, Thomas

    2008-03-01

    Dental drug delivery systems have been used for a long time, in particular for the local therapy of diseases affecting the oral cavity. Research today concentrates on the design of formulations to increase their retention time. Even today, however, prosthetic devices incorporating drug delivery are rarely used. Mainly, they are focused on prophylaxis and the release of antibacterial agents. However, as buccal delivery, because of its undeniable advantages, has become popular for systemic drug delivery, and prolonged well-controlled release has been identified as beneficial, especially for chronic diseases, a new class of delivery systems is evolving: highly miniaturized computerized delivery systems, integrated into a dental appliance. Dental delivery systems today are used in two ways: the main application is the local treatment of diseases affecting the oral cavity itself like periodontitis or fungal infections. The second is for systemic drug delivery.

  8. 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

  9. In vitro evaluation of paclitaxel loaded amorphous chitin nanoparticles for colon cancer drug delivery.

    PubMed

    Smitha, K T; Anitha, A; Furuike, T; Tamura, H; Nair, Shantikumar V; Jayakumar, R

    2013-04-01

    Chitin and its derivatives have been widely used in drug delivery applications due to its biocompatible, biodegradable and non-toxic nature. In this study, we have developed amorphous chitin nanoparticles (150±50 nm) and evaluated its potential as a drug delivery system. Paclitaxel (PTX), a major chemotherapeutic agent was loaded into amorphous chitin nanoparticles (AC NPs) through ionic cross-linking reaction using TPP. The prepared PTX loaded AC NPs had an average diameter of 200±50 nm. Physico-chemical characterization of the prepared nanoparticles was carried out. These nanoparticles were proven to be hemocompatible and in vitro drug release studies showed a sustained release of PTX. Cellular internalization of the NPs was confirmed by fluorescent microscopy as well as by flow cytometry. Anticancer activity studies proved the toxicity of PTX-AC NPs toward colon cancer cells. These preliminary results indicate the potential of PTX-AC NPs in colon cancer drug delivery. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Confirmation of Drug Delivery after Liver Chemoembolization: Direct Tissue Doxorubicin Measurement by UHPLC-MS-MS

    PubMed Central

    Baumgarten, Sigrid; Gaba, Ron C.; van Breemen, Richard B.

    2012-01-01

    Because liver cancer is rarely suitable for surgery, transcatheter arterial chemoembolization (TACE) is used for palliative therapy. In this procedure, an emulsion of doxorubicin in iodized oil is injected directly into liver tumors through a catheter positioned within the artery supplying blood flow to the tumor. At present, there is limited understanding of factors affecting the delivery and dispersion of doxorubicin within treated tumors during TACE. This study addresses the development and application of an ultrahigh pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS-MS) method for rapid confirmation of drug delivery after TACE in a rabbit VX2 liver cancer model. Doxorubicin levels in liver tumors were measured using UHPLC-MS-MS and compared with computed tomography measured levels of iodized oil, a metric used clinically to indicate drug delivery. We found that tissue drug levels determined using UHPLC-MS-MS did not correlate with the regional iodized oil concentration (vehicle) within tumors following TACE, suggesting that chemotherapeutic drugs like doxorubicin spread throughout tumors, and that lack of iodized oil staining in portions of a tumor does not necessarily indicate inadequate therapy during TACE. PMID:22454282

  11. 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.

  12. Albumin nanostructures as advanced drug delivery systems.

    PubMed

    Karimi, Mahdi; Bahrami, Sajad; Ravari, Soodeh Baghaee; Zangabad, Parham Sahandi; Mirshekari, Hamed; Bozorgomid, Mahnaz; Shahreza, Somayeh; Sori, Masume; Hamblin, Michael R

    2016-11-01

    One of the biggest impacts that the nanotechnology has made on medicine and biology, has been in the area of drug delivery systems (DDSs). Many drugs suffer from serious problems concerning insolubility, instability in biological environments, poor uptake into cells and tissues, sub-optimal selectivity for targets and unwanted side effects. Nanocarriers can be designed as DDSs to overcome many of these drawbacks. One of the most versatile building blocks to prepare these nanocarriers is the ubiquitous, readily available and inexpensive protein, serum albumin. Areas covered: This review covers the use of different types of albumin (human, bovine, rat, and chicken egg) to prepare nanoparticle and microparticle-based structures to bind drugs. Various methods have been used to modify the albumin structure. A range of targeting ligands can be attached to the albumin that can be recognized by specific cell receptors that are expressed on target cells or tissues. Expert opinion: The particular advantages of albumin used in DDSs include ready availability, ease of chemical modification, good biocompatibility, and low immunogenicity. The regulatory approvals that have been received for several albumin-based therapeutic agents suggest that this approach will continue to be successfully explored.

  13. 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.

  14. 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

  15. 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

  16. Superparamagnetic reconstituted high-density lipoprotein nanocarriers for magnetically guided drug delivery

    PubMed Central

    Sabnis, Sarika; Sabnis, Nirupama A; Raut, Sangram; Lacko, Andras G

    2017-01-01

    Current cancer chemotherapy is frequently associated with short- and long-term side effects, affecting the quality of life of cancer survivors. Because malignant cells are known to overexpress specific surface antigens, including receptors, targeted drug delivery is often utilized to reduce or overcome side effects. The current study involves a novel targeting approach using specifically designed nanoparticles, including encapsulation of the anti-cancer drug valrubicin into superparamagnetic iron oxide nanoparticle (SPION) containing reconstituted high-density lipoprotein (rHDL) nanoparticles. Specifically, rHDL–SPION–valrubicin hybrid nanoparticles were assembled and characterized with respect to their physical and chemical properties, drug entrapment efficiency and receptor-mediated release of the drug valrubicin from the nanoparticles to prostate cancer (PC-3) cells. Prussian blue staining was used to assess nanoparticle movement in a magnetic field. Measurements of cytotoxicity toward PC-3 cells showed that rHDL–SPION–valrubicin nanoparticles were up to 4.6 and 31 times more effective at the respective valrubicin concentrations of 42.4 µg/mL and 85 µg/mL than the drug valrubicin alone. These studies showed, for the first time, that lipoprotein drug delivery enhanced via magnetic targeting could be an effective chemotherapeutic strategy for prostate cancer. PMID:28260891

  17. Controlled drug delivery systems: past forward and future back.

    PubMed

    Park, Kinam

    2014-09-28

    Controlled drug delivery technology has progressed over the last six decades. This progression began in 1952 with the introduction of the first sustained release formulation. The 1st generation of drug delivery (1950-1980) focused on developing oral and transdermal sustained release systems and establishing controlled drug release mechanisms. The 2nd generation (1980-2010) was dedicated to the 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 largely focused on studying nanoparticle formulations. The Journal of Controlled Release (JCR) has played a pivotal role in the 2nd generation of drug delivery technologies, and it will continue playing a leading role in the next generation. The best path towards a productive 3rd generation of drug delivery technology requires an honest, open dialog without any preconceived ideas of the past. The drug delivery field needs to take a bold approach to designing future drug delivery formulations primarily based on today's necessities, to produce the necessary innovations. The JCR provides a forum for sharing the new ideas that will shape the 3rd generation of drug delivery technology. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. 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

  19. The involvement of hypoxia-inducible factor-1alpha in the susceptibility to gamma-rays and chemotherapeutic drugs of oral squamous cell carcinoma cells.

    PubMed

    Sasabe, Eri; Zhou, Xuan; Li, Dechao; Oku, Naohisa; Yamamoto, Tetsuya; Osaki, Tokio

    2007-01-15

    The transcription factor hypoxia-inducible factor-1alpha (HIF-1alpha) is the key regulator that controls the hypoxic response of mammalian cells. The overexpression of HIF-1alpha has been demonstrated in many human tumors. However, the role of HIF-1alpha in the therapeutic efficacy of chemotherapy and radiotherapy in cancer cells is poorly understood. In this study, we investigated the influence of HIF-1alpha expression on the susceptibility of oral squamous cell carcinoma (OSCC) cells to chemotherapeutic drugs (cis-diamminedichloroplatinum and 5-fluorouracil) and gamma-rays. Treatment with chemotherapeutic drugs and gamma-rays enhanced the expression and nuclear translocation of HIF-1alpha, and the susceptibility of OSCC cells to the drugs and gamma-rays was negatively correlated with the expression level of HIF-1alpha protein. The overexpression of HIF-1alpha induced OSCC cells to become more resistant to the anticancer agents, and down-regulation of HIF-1alpha expression by small interfering RNA enhanced the susceptibility of OSCC cells to them. In the HIF-1alpha-knockdown OSCC cells, the expression of P-glycoprotein, heme oxygenase-1, manganese-superoxide dismutase and ceruloplasmin were downregulated and the intracellular levels of chemotherapeutic drugs and reactive oxygen species were sustained at higher levels after the treatment with the anticancer agents. These results suggest that enhanced HIF-1alpha expression is related to the resistance of tumor cells to chemo- and radio-therapy and that HIF-1alpha is an effective therapeutic target for cancer treatment.

  20. 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

  1. Lipid formulation as a drug carrier for drug delivery.

    PubMed

    Tomii, Yoshifumi

    2002-01-01

    In recent years, a Drug Delivery System (DDS), a preparative approach attracts the attention in the development of new drugs. DDS focuses on the regulation of the in vivo dynamics, such as absorption, distribution, metabolism, and elimination, thereby improving the effectiveness and the safety of the drugs by an applicable use of drug preparation technologies. A conventional intravenous dosage form of Amphotericin B (AmB), Fungizone, is the most effective clinically available for treating fungal infections. However, the clinical efficacy of AmB is limited by its adverse effects. Several lipid formulations, such as Liposomal AmB (L-AmB), AmB lipid complex (ABLC), and AmB colloidal dispersion (ABCD), with reduced side effects have been developed. These formulations are reported to have excellent safety and efficacy. However, comparable efficacy can be achieved only when they are administered at high doses than AmB. One of the problems of using these formulations is that they are easily taken up by the reticuloendothelial system (RES). An artificial lipoprotein-like particles, a novel drug carrier Lipid Nano-Sphere (LNS), which is 25 - 50 nm in size and is composed of phospholipids and simple lipid. LNS show a higher plasma concentration of drugs and lower uptake by RES-tissue different forms other lipid base drug carriers. In vitro and in vivo, LNS incorporating AmB, NS-718, shows reduced toxicity, while maintaining activity against fungi. LNS have a unique characteristic as an effective carrier of AmB for treatment of fungal infection.

  2. 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

  3. Herbal Excipients in Novel Drug Delivery Systems

    PubMed Central

    Shirwaikar, A.; Shirwaikar, Annie; Prabu, S. Lakshmana; Kumar, G. Aravind

    2008-01-01

    The use of natural excipients to deliver the bioactive agents has been hampered by the synthetic materials. However advantages offered by these natural excipients are their being non-toxic, less expensive and freely available. The performance of the excipients partly determines the quality of the medicines. The traditional concept of the excipients as any component other than the active substance has undergone a substantial evolution from an inert and cheap vehicle to an essential constituent of the formulation. Excipients are any component other than the active substance(s) intentionally added to formulation of a dosage form. This article gives an overview of herbal excipients which are used in conventional dosage forms as well as novel drug delivery systems. PMID:20046764

  4. 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

  5. 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.

  6. Microneedle arrays for biosensing and drug delivery

    DOEpatents

    Wang, Joseph; Windmiller, Joshua Ray; Narayan, Roger; Miller, Philip

    2017-08-29

    Methods, structures, and systems are disclosed for biosensing and drug delivery techniques. In one aspect, a device for detecting an analyte and/or releasing a biochemical into a biological fluid can include an array of hollowed needles, in which each needle includes a protruded needle structure including an exterior wall forming a hollow interior and an opening at a terminal end of the protruded needle structure that exposes the hollow interior, and a probe inside the exterior wall to interact with one or more chemical or biological substances that come in contact with the probe via the opening to produce a probe sensing signal, and an array of wires that are coupled to probes of the array of hollowed needles, respectively, each wire being electrically conductive to transmit the probe sensing signal produced by a respective probe.

  7. Microneedle arrays for biosensing and drug delivery

    DOEpatents

    Wang, Joseph; Windmiller, Joshua Ray; Narayan, Roger; Miller, Philip; Polsky, Ronen; Edwards, Thayne L.

    2017-08-22

    Methods, structures, and systems are disclosed for biosensing and drug delivery techniques. In one aspect, a^ device for detecting an analyte and/or releasing a biochemical into a biological fluid can include an array of hollowed needles, in which each needle includes a protruded needle structure including an exterior wall forming a hollow interior and an opening at a terminal end of the protruded needle structure that exposes the hollow interior, and a probe inside the exterior wall to interact with one or more chemical or biological substances that come in contact with the probe via the opening to produce a probe sensing signal, and an array of wires that are coupled to probes of the array of hollowed needles, respectively, each wire being electrically conductive to transmit the probe sensing signal produced by a respective probe.

  8. Supramolecular hydrogels as drug delivery systems.

    PubMed

    Saboktakin, Mohammad Reza; Tabatabaei, Roya Mahdavi

    2015-04-01

    Drug delivery from a hydrogel carrier implanted under the kidney capsule is an innovative way to induce kidney tissue regeneration and/or prevent kidney inflammation or fibrosis. We report here on the development of supramolecular hydrogels for this application. Chain-extended hydrogelators containing hydrogen bonding units in the main chain, and bifunctional hydrogelators end-functionalized with hydrogen bonding moieties, were made. The influence of these hydrogels on the renal cortex when implanted under the kidney capsule was studied. The overall tissue response to these hydrogels was found to be mild, and minimal damage to the cortex was observed, using the infiltration of macrophages, formation of myofibroblasts, and the deposition of collagen III as relevant read-out parameters. Differences in tissue response to these hydrogels could be related to the different physico-chemical properties of the three hydrogels.

  9. Biomimetic transport and rational drug delivery.

    PubMed

    Ranney, D F

    2000-01-15

    Medicine and pharmaceutics are encountering critical needs and opportunities for transvascular drug delivery that improves site targeting and tissue permeation by mimicking natural tissue addressing and transport mechanisms. This is driven by the accelerated development of genomic agents requiring targeted controlled release. Although rationally designed for in vitro activity, such agents are not highly effective in vivo, due to opsonization and degradation by plasma constituents, and failure to transport across the local vascular endothelium and tissue matrix. A growing knowledge of the addresses of the body can be applied to engineer "Bio-Logically" staged delivery systems with sequential bioaddressins complementary to the discontinuous compartments encountered--termed discontinuum pharmaceutics. Effective tissue targeting is accomplished by leukocytes, bacteria, and viruses. We are increasingly able to mimic their bioaddressins by genomic means. Approaches described in this commentary include: (a) endothelial-directed adhesion mediated by oligosaccharides and carbohydrates (e.g. dermatan sulfate as a mimic of sulfated CD44) and peptidomimetics interacting with adhesins, selectins, integrins, hyaluronans, and locally induced growth factors (e.g. vascular endothelial growth factor, VEGF) and coagulation factors (e.g. factor VIII antigen); (b) improved tissue permeation conferred by hydrophilically "cloaked" carrier systems; (c) "uncloaking" by matrix dilution or selective triggering near the target cells; and (d) target binding-internalization by terminally exposed hydrophobic moieties, cationic polymers, and receptor-binding lectins, peptides, or carbohydrates. This commentary also describes intermediate technology solutions (e.g. "hybrid drugs"), and highlights the high-resolution, dynamic magnetic resonance imaging and radiopharmaceutical imaging technologies plus the groups and organizations capable of accelerating these important initiatives.

  10. 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

  11. Applications of Carbon-Based Nanomaterials for Drug Delivery in Oncology

    NASA Astrophysics Data System (ADS)

    Levi-Polyachenko, Nicole H.; Carroll, David L.; Stewart, John H.

    The goal of this chapter is to introduce carbon nanomaterials and highlight research focused on their use as cancer therapeutics. The physical properties of fullerenes and carbon nanotubes, including their spectral characteristics are described. Current oncology treatment regimes are described to provide an overview of where carbon nanomaterials may have significant value in further development of the established standards of care procedures. Photodynamic therapy and drug delivery using fullerene C60 is explored. Thermal ablation techniques using carbon nanotubes are explained and alternate hyperthermic methods using carbon nanotubes are described. Specifically, carbon nanotubes are examined for their potential contribution to the currently practiced clinical therapy intraperitoneal hyperthermic chemoperfusion. Nanotubes and nanohorns filled with chemotherapeutic agents are examined as are different methods for filling and containment of drug moieties. The attachment of active molecules to fullerenes is described with examples for use in oncology. Toxicity issues are explored and the future directions and potential for carbon nanomaterial types concludes the chapter.

  12. 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

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

    PubMed

    Li, Zhi Jie; Cho, Chi Hin

    2012-09-19

    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.

  14. Light-switchable systems for remotely controlled drug delivery.

    PubMed

    Shim, Gayong; Ko, Seungbeom; Kim, Dongyoon; Le, Quoc-Viet; Park, Gyu Thae; Lee, Jaiwoo; Kwon, Taekhyun; Choi, Han-Gon; Kim, Young Bong; Oh, Yu-Kyoung

    2017-09-06

    Light-switchable systems have recently received attention as a new mode of remotely controlled drug delivery. In the past, a multitude of nanomedicine studies have sought to enhance the specificity of drug delivery to target sites by focusing on receptors overexpressed on malignant cells or environmental features of diseases sites. Despite these immense efforts, however, there are few clinically available nanomedicines. We need a paradigm shift in drug delivery. One strategy that may overcome the limitations of pathophysiology-based drug delivery is the use of remotely controlled delivery technology. Unlike pathophysiology-based active drug targeting strategies, light-switchable systems are not affected by the heterogeneity of cells, tissue types, and/or microenvironments. Instead, they are triggered by remote light (i.e., near-infrared) stimuli, which are absorbed by photoresponsive molecules or three-dimensional nanostructures. The sequential conversion of light to heat or reactive oxygen species can activate drug release and allow it to be spatio-temporally controlled. Light-switchable systems have been used to activate endosomal drug escape, modulate the release of chemical and biological drugs, and alter nanoparticle structures to control the release rates of drugs. This review will address the limitations of pathophysiology-based drug delivery systems, the current status of light-based remote-switch systems, and future directions in the application of light-switchable systems for remotely controlled drug delivery. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Doxorubicin loaded magnetic gold nanoparticles for in vivo targeted drug delivery.

    PubMed

    Elbialy, Nihal Saad; Fathy, Mohamed Mahmoud; Khalil, Wafaa Mohamed

    2015-07-25

    Treatment of approximately 50% of human cancers includes the use of chemotherapy. The major problem associated with chemotherapy is the inability to deliver pharmaceuticals to specific site of the body without inducing normal tissue toxicity. Latterly, magnetic targeted drug delivery (MTD) has been used to improve the therapeutic performance of the chemotherapeutic agents and reduce the severe side effects associated with the conventional chemotherapy for malignant tumors. In this study, we were focused on designing biocompatible magnetic nanoparticles that can be used as a nanocarrier's candidate for MTD regimen. Magnetic gold nanoparticles (MGNPs) were prepared and functionalized with thiol-terminated polyethylene glycol (PEG), then loaded with anti-cancer drug doxorubicin (DOX). The physical properties of the prepared NPs were characterized using different techniques. Transmission electron microscopy (TEM) revealed the spherical mono-dispersed nature of the prepared MGNPs with size about 22 nm. Energy dispersive X-ray spectroscopy (EDX) assured the existence of both iron and gold elements in the prepared nanoparticles. Fourier transform infrared (FTIR) spectroscopy assessment revealed that PEG and DOX molecules were successfully loaded on the MGNPs surfaces, and the amine group of DOX is the active attachment site to MGNPs. In vivo studies proved that magnetic targeted drug delivery can provide a higher accumulation of drug throughout tumor compared with that delivered by passive targeting. This clearly appeared in tumor growth inhibition assessment, biodistribution of DOX in different body organs in addition to the histopathological examinations of treated and untreated Ehrlich carcinoma. To assess the in vivo toxic effect of the prepared formulations, several biochemical parameters such as aspartate aminotransferase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH), creatine kinase MB (CK-MB), urea, uric acid and creatinine were measured. MTD

  16. Multiscale Imaging of Nanoparticle Drug Delivery.

    PubMed

    Dobrucki, Lawrence W; Pan, Dipanjan; Smith, Andrew M

    2015-01-01

    Nanoparticles have recently had a major impact on basic biosciences, the pharmaceutical industry, and preclinical and translational medicine by enabling targeted delivery of therapeutic cargo to cells and tissues. The capacity to specifically tailor the pharmacokinetics, biodistribution, and longterm fate of therapeutic molecules for specific diseases and to avoid off-target side effects is a tremendously promising capability of these materials. However targeting of nanoparticle therapies from systemic circulation is very inefficient, and our understanding of the fundamental processes dictating in vivo fate remains limited, making it challenging to determine how to optimally and rationally design these materials for maximum efficacy. Recently multi-modal, multi-scale imaging technologies have emerged that have helped to improve our insight into these processes. Theranostic imaging agents have provided real-time and quantitative readouts of drug distribution and therapeutic response, multimodal imaging platforms have allowed a multi-scale analysis of distribution from the levels of cells to tissues, and exciting applications in live-animal tissue microscopy have provided key insights at the cellular level. In this review, we describe how multiscale imaging has shaped our ability to optimize nanoparticle drugs and discuss future directions that are expected to further catalyze clinical translation.

  17. Nanostructured porous silicon-mediated drug delivery.

    PubMed

    Martín-Palma, Raúl J; Hernández-Montelongo, Jacobo; Torres-Costa, Vicente; Manso-Silván, Miguel; Muñoz-Noval, Álvaro

    2014-08-01

    The particular properties of nanostructured porous silicon (nanoPS) make it an attractive material for controlled and localized release of therapeutics within the body, aiming at increased efficacy and reduced risks of potential side effects. Since this is a rapidly evolving field as a consequence of the number of research groups involved, a critical review of the state of the art is necessary. In this work, the most promising and successful applications of nanoPS in the field of drug delivery are reviewed and discussed. Two key issues such as drug loading and release are also analyzed in detail. The development of multifunctional (hybrid) systems, aiming at imparting additional functionalities to the nanoPS particles such as luminescence, magnetic response and/or plasmonic effects (allowing simultaneous tracking and guiding), is also examined. Nanostructured materials based on silicon are promising platforms for pharmaceutical applications given their ability to degrade and low toxicity. However, a very limited number of clinical applications have been demonstrated so far.

  18. 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.

  19. Biodegradable Polymeric Nanoparticles as the Delivery Carrier for Drug.

    PubMed

    Zhao, Kai; Li, Dan; Shi, Ci; Ma, Xueling; Rong, Guangu; Kang, Hong; Wang, Xiaohua; Sun, Bin

    2016-01-01

    Drug research and development has entered into the new epoch of innovation formulation, and the drug delivery system has been in the forefront of pharmaceutical innovation. Nanotechnology is widely used in fiber and textiles, electronics, space, agriculture, forensic science and medical therapeutics. It increasingly plays a significant role in drug delivery system. Compared with traditional delivery system, the nanoparticle drug delivery system has lots of merits, such as the high drug loading ability, the excellent biocompatibility, low toxicity, controlled and targeted drug release. We undertook a structured research of biodegradable polymeric nanoparticles used as delivery carrier for drug using a focused review question and inclusion/exclusion criteria. We have searched the bibliographic databases for peerreviewed research literature. The outstanding characteristics of the screened papers were described respectively, and a systematic content analysis methodology was used to analysis the findings. Seventy-three papers were included in the review, the majority defined leadership and governance approaches that had impacted upon the polymeric nanoparticles as the delivery carrier for drug in therapeutic applications and developments. Seven papers outlined the superiority characteristics of polymeric nanoparticles that applied in the field of vaccine. Forty-seven papers overviewed the application prospects of polymeric nanoparticles used as drug delivery carrier for cancer. These included current advances in research and clinical applications of polymeric nanoparticles. The review identified the drug delivery carrier of biodegradable polymeric nanoparticles, and we described the synthesis methods, applications and challenges of polymeric nanoparticles. The findings of this review identified that the biodegradable polymeric nanoparticles were used as delivery carrier for drug currently. It also indicates that the biodegradable polymeric nanoparticles play an

  20. 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.

  1. 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

  2. Hierarchical pulmonary target nanoparticles via inhaled administration for anticancer drug delivery.

    PubMed

    Chen, Rui; Xu, Liu; Fan, Qin; Li, Man; Wang, Jingjing; Wu, Li; Li, Weidong; Duan, Jinao; Chen, Zhipeng

    2017-11-01

    Inhalation administration, compared with intravenous administration, significantly enhances chemotherapeutic drug exposure to the lung tissue and may increase the therapeutic effect for pulmonary anticancer. However, further identification of cancer cells after lung deposition of inhaled drugs is necessary to avoid side effects on normal lung tissue and to maximize drug efficacy. Moreover, as the action site of the major drug was intracellular organelles, drug target to the specific organelle is the final key for accurate drug delivery. Here, we designed a novel multifunctional nanoparticles (MNPs) for pulmonary antitumor and the material was well-designed for hierarchical target involved lung tissue target, cancer cell target, and mitochondrial target. The biodistribution in vivo determined by UHPLC-MS/MS method was employed to verify the drug concentration overwhelmingly increasing in lung tissue through inhaled administration compared with intravenous administration. Cellular uptake assay using A549 cells proved the efficient receptor-mediated cell endocytosis. Confocal laser scanning microscopy observation showed the location of MNPs in cells was mitochondria. All results confirmed the intelligent material can progressively play hierarchical target functions, which could induce more cell apoptosis related to mitochondrial damage. It provides a smart and efficient nanocarrier platform for hierarchical targeting of pulmonary anticancer drug. So far, this kind of material for pulmonary mitochondrial-target has not been seen in other reports.

  3. Drug delivery systems for differential release in combination therapy.

    PubMed

    Zhang, Hongbin; Wang, Guojie; Yang, Huai

    2011-02-01

    Combination therapy with multiple therapeutic agents has wide applicability in medical and surgical treatment, especially in the treatment of cancer. Thus, new drug delivery systems that can differentially release two or more drugs are desired. Utilizing new techniques to engineer the established drug delivery systems and synthesizing new materials and designing carriers with new structures are feasible ways to fabricate proper multi-agent delivery systems, which are critical to meet requirements in the clinic and improve therapeutic efficacy. This paper aims to give an overview about the multi-agent delivery systems developed in the last decade for differential release in combination therapy. Multi-agent delivery systems from nanoscale to bulk scale, such as liposomes, micelles, polymer conjugates, nano/microparticles and hydrogels, developed over the last 10 years, have been collected and summarized. The characteristics of different delivery systems are described and discussed, including the structure of drug carriers, drug-loading techniques, release behaviors and consequent evaluation in biological assays. The chemical structure of drug delivery systems is the key to controlling the release of therapeutic agents in combination therapy, and the differential release of multiple drugs could be realized by the successful design of a proper delivery system. Besides biological evaluation in vitro and in vivo, it is important to speed up practical application of the resulting delivery systems.

  4. [Chemotherapeutic agents under study].

    PubMed

    Kawahara, S

    1998-12-01

    The development of new drugs with strong antituberculous activity and fewer side effects which are not cross-resistant to conventional antituberculosis drugs is urgently desired now. The chemotherapeutic agents under study which are considered a candidate for a new antituberculosis drug are listed below. 1) Rifamycin derivatives: rifabutin, rifapentin, KRM-1648, FCE-22250, 22807, CGP-7040, 27557, 29035, 29861, P-DEA, SPA-S-565, R-76-1. 2) New quinolones: ofloxacin, ciprofloxacin, levofloxacin, sparfloxacin, gatifloxacin, CS-940, Du-6859a. 3) Phenazines: clofazimine, B746, B4101, B4154, B4157. 4) Pyrazinamide derivatives: N-hydroxy pyrazinamide, N-hydroxy pyrazinamide-4-oxide. 5) Nitroimidazole derivatives: metronidazole et al.

  5. Programmable biomaterials for dynamic and responsive drug delivery

    PubMed Central

    Stejskalová, Anna; Kiani, Mehrdad T

    2016-01-01

    Biomaterials are continually being designed that enable new methods for interacting dynamically with cell and tissues, in turn unlocking new capabilities in areas ranging from drug delivery to regenerative medicine. In this review, we explore some of the recent advances being made in regards to programming biomaterials for improved drug delivery, with a focus on cancer and infection. We begin by explaining several of the underlying concepts that are being used to design this new wave of drug delivery vehicles, followed by examining recent materials systems that are able to coordinate the temporal delivery of multiple therapeutics, dynamically respond to changing tissue environments, and reprogram their bioactivity over time. PMID:27190245

  6. 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

  7. Clinical Considerations of Focal Drug Delivery In Cancer Treatment.

    PubMed

    Harris, Jamie; Chiu, Bill

    2017-02-24

    According to the US Center for Disease Control, cancer deaths are the second most common cause of mortality in both adults and children. Definitive treatment of solid tumors involves surgical resection with or without systemic chemotherapy and radiation. The advent of local drug delivery presents a unique treatment modality that can offer substantial benefits in cancer management. Local drug delivery offers targeted drug delivery to cancer tissues while minimizing side effects of the medications. Three main phases in solid tumor management exist for the treating physician: initial diagnosis with tissue biopsy, surgical resection with or without chemotherapy, and management of metastatic disease. Image guided studies, using modalities such as MRI, computerized tomography, and ultrasound to sample tumors have been described. The initial diagnosis phase offers a treatment window for local drug delivery with the aid of image guidance. After the diagnosis of malignancy is made, surgical resection can become an important part of tumor management. Currently, FDA approved local drug delivery systems are being used in concert with resection for intracranial glioma. Many other applications of implantation of local drug delivery at the time of surgery in other tumors, including breast and neuroblastoma, are being investigated. Finally, for patients who present with or progress to single sites of metastatic disease, such as brain or liver metastasis, studies have shown potential applications for local drug delivery as well. This review will discuss the current state of local drug delivery in the treatment of solid tumors and possible future directions.

  8. Clinical applications of biomedical microdevices for controlled drug delivery.

    PubMed

    Gurman, Pablo; Miranda, Oscar R; Clayton, Kevin; Rosen, Yitzhak; Elman, Noel M

    2015-01-01

    Miniaturization of devices to micrometer and nanometer scales, combined with the use of biocompatible and functional materials, has created new opportunities for the implementation of drug delivery systems. Advances in biomedical microdevices for controlled drug delivery platforms promise a new generation of capabilities for the treatment of acute conditions and chronic illnesses, which require high adherence to treatment, in which temporal control over the pharmacokinetic profiles is critical. In addition, clinical conditions that require a combination of drugs with specific pharmacodynamic profiles and local delivery will benefit from drug delivery microdevices. This review provides a summary of various clinical applications for state-of-the-art controlled drug delivery microdevices, including cancer, endocrine and ocular disorders, and acute conditions such as hemorrhagic shock. Regulatory considerations for clinical translation of drug delivery microdevices are also discussed. Drug delivery microdevices promise a remarkable gain in clinical outcomes and a substantial social impact. A review of articles covering the field of microdevices for drug delivery was performed between January 1, 1990, and January 1, 2014, using PubMed as a search engine.

  9. Drug Delivery Approaches for the Treatment of Cervical Cancer

    PubMed Central

    Ordikhani, Farideh; Erdem Arslan, Mustafa; Marcelo, Raymundo; Sahin, Ilyas; Grigsby, Perry; Schwarz, Julie K.; Azab, Abdel Kareem

    2016-01-01

    Cervical cancer is a highly prevalent cancer that affects women around the world. With the availability of new technologies, researchers have increased their efforts to develop new drug delivery systems in cervical cancer chemotherapy. In this review, we summarized some of the recent research in systematic and localized drug delivery systems and compared the advantages and disadvantages of these methods. PMID:27447664

  10. 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

  11. 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

  12. 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

  13. Potential of nanoparticulate drug delivery systems by intranasal administration.

    PubMed

    Ali, Javed; Ali, Mushir; Baboota, Sanjula; Sahani, Jasjeet Kaur; Ramassamy, Charles; Dao, Lé; Bhavna

    2010-05-01

    Due to number of problems related with oral, parenteral, rectal and other routes of drug administration, the interest of pharmaceutical scientists has increased towards exploring the possibilities of intranasal delivery of various drugs. Nasal drug delivery system is commonly known for the treatment of local ailments like cold, cough, rhinitis, etc. Efforts have been made to deliver various drugs, especially peptides and proteins, through nasal route for systemic use; utilizing the principles and concepts of various nanoparticulate drug delivery systems using various polymers and absorption promoters. The incorporation of drugs into nanoparticles might be a promising approach, since colloidal formulations have been shown to protect them from the degrading milieu in the nasal cavity and facilitate their transport across the mucosal barriers. The use of nanoparticles for vaccine delivery provides beneficial effect, by achieving good immune responses. This could be due to the fact that small particles can be transported preferentially by the lymphoid tissue of the nasal cavity (NALT). The brain gets benefited through the intranasal delivery as direct olfactory transport bypasses the blood brain barrier and nanoparticles are taken up and conveyed along cell processes of olfactory neurons through the cribriform plate to synaptic junctions with neurons of the olfactory bulb. The intranasal delivery is aimed at optimizing drug bioavailability for systemic drugs, as absorption decreases with increasing molecular weight, and for drugs, which are susceptible to enzymatic degradation such as proteins and polypeptides. This review discusses the potential benefits of using nanoparticles for nasal delivery of drugs and vaccines for brain, systemic and topical delivery. The article aims at giving an insight into nasal cavity, consideration of factors affecting and strategies to improve drug absorption through nasal route, pharmaceutical dosage forms and delivery systems with

  14. Different concepts of drug delivery in disease entities.

    PubMed

    Serafin, A; Stańczak, A

    2009-04-01

    This is a review of classical and novel concepts of drug delivery in particular diseases such as central nervous system disease, ophthalmic disease, cardiovascular disease, cancer and others. Nowadays, scientists are trying to propose efficient and selective drugs for the site of action, with best acceptance of patients, that can be metabolized to non-toxic derivatives. Prodrugs, soft drugs, codrugs are designed to maximize the amount of active drugs that reaches the site of action, through changing the physicochemical, biopharmaceutical or pharmacokinetic properties of the parent drugs. For last years different concepts of drug delivery have been developed to achieve the best patients' tolerance of a drug that has no undesirable properties. It is established that future studies will ameliorate drug properties so as to achieve the best drug delivery system.

  15. Advances in image-guided intratumoral drug delivery techniques

    PubMed Central

    Solorio, Luis; Patel, Ravi B; Wu, Hanping; Krupka, Tianyi; Exner, Agata A

    2017-01-01

    Image-guided drug delivery provides a means for treating a variety of diseases with minimal systemic involvement while concurrently monitoring treatment efficacy. These therapies are particularly useful to the field of interventional oncology, where elevation of tumor drug levels, reduction of systemic side effects and post-therapy assessment are essential. This review highlights three such image-guided procedures: transarterial chemoembolization, drug-eluting implants and convection-enhanced delivery. Advancements in medical imaging technology have resulted in a growing number of new applications, including image-guided drug delivery. This minimally invasive approach provides a comprehensive answer to many challenges with local drug delivery. Future evolution of imaging devices, image-acquisition techniques and multifunctional delivery agents will lead to a paradigm shift in patient care. PMID:22816134

  16. The impact of ageing on the barriers to drug delivery.

    PubMed

    Perrie, Yvonne; Badhan, Raj K Singh; Kirby, Daniel J; Lowry, Deborah; Mohammed, Afzal R; Ouyang, Defang

    2012-07-20

    Generally, we like to see ageing as a process that is happening to people older than ourselves. However the process of ageing impacts on a wide range of functions within the human body. Whilst many of the outcomes of ageing can now be delayed or reduced, age-related changes in cellular, molecular and physiological functionality of tissues and organs can also influence how drugs enter, distribute and are eliminated from the body. Therefore, the changing profile of barriers to drug delivery should be considered if we are to develop more age-appropriate medicines. Changes in the drug dissolution and absorption in older patients may require the formulation of oral delivery systems that offer enhanced retention at absorption sites to improve drug delivery. Alternatively, liquid and fast-melt dosage systems may address the need of patients who have difficulties in swallowing medication. Ageing-induced changes in the lung can also result in slower drug absorption, which is further compounded by disease factors, common in an ageing population, that reduce lung capacity. In terms of barriers to drug delivery to the eye, the main consideration is the tear film, which like other barriers to drug delivery, changes with normal ageing and can impact on the bioavailability of drugs delivery using eye drops and suspensions. In contrast, whilst the skin as a barrier changes with age, no significant difference in absorption of drugs from transdermal drug delivery is observed in different age groups. However, due to the age-related pharmacokinetic and pharmacodynamic changes, dose adaptation should still be considered for drug delivery across the skin. Overall it is clear that the increasing age demographic of most populations, presents new (or should that be older) barriers to effective drug delivery.

  17. 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