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Sample records for oil nanocapsules frozen

  1. All natural cellulose acetate-Lemongrass essential oil antimicrobial nanocapsules.

    PubMed

    Liakos, Ioannis L; D'autilia, Francesca; Garzoni, Alice; Bonferoni, Cristina; Scarpellini, Alice; Brunetti, Virgilio; Carzino, Riccardo; Bianchini, Paolo; Pompa, Pier Paolo; Athanassiou, Athanassia

    2016-08-30

    Nanocapsules and nanoparticles play an essential role in the delivery of pharmaceutical agents in modern era, since they can be delivered in specific tissues and cells. Natural polymers, such as cellulose acetate, are becoming very important due to their availability, biocompatibility, absence of toxicity and biodegradability. In parallel, essential oils are having continuous growth in biomedical applications due to the inherent active compounds that they contain. A characteristic example is lemongrass oil that has exceptional antimicrobial properties. In this work, nanocapsules of cellulose acetate with lemongrass oil were developed with the solvent/anti-solvent method with resulting diameter tailored between 95 and 185nm. Various physico-chemical and surface analysis techniques were employed to investigate the formation of the nanocapsules. These all-natural nanocapsules found to well bioadhere to mucous membranes and to have very good antimicrobial properties at little concentrations against Escherichia coli and Staphylococcus aureus.

  2. Chitosan-alginate nanocapsules for encapsulation of turmeric oil.

    PubMed

    Lertsutthiwong, P; Rojsitthisak, P

    2011-12-01

    Turmeric oil is widely used in pharmaceutical and cosmetic applications because of its antibacterial, antifungal, antioxidant, and insect-repellent properties. However, turmeric oil is volatile, insoluble in water and unstable in certain environments, which causes difficulties with formulation development and stability of new products. One approach to overcome these problems is to encapsulate turmeric oil in carriers formed from naturally occurring polysaccharides. Among such polysaccharides, chitosan and alginate have been widely used as particulate carriers for encapsulation and controlled release of bioactive compounds. The potential for size reduction of the carriers to the nanometer scale is of particular interest for delivery systems. In this review, we provide an overview of the versatile properties of turmeric oil and discuss the use of alginate and chitosan for capsule formation and encapsulation of turmeric oil in chitosan-alginate nanocapsules. We also discuss the in vitro skin permeation of turmeric oil from nanocapsules.

  3. Formulation of essential oil-loaded chitosan-alginate nanocapsules.

    PubMed

    Natrajan, Dheebika; Srinivasan, Sharmila; Sundar, K; Ravindran, Aswathy

    2015-09-01

    Naturally occurring polymers such as alginate (AL) and chitosan (CS) are widely used in biomedical and pharmaceutical fields in various forms such as nanoparticles, capsules, and emulsions. These polymers have attractive applications in drug delivery because of their biodegradability, biocompatibility, and nontoxic nature. The pharmaceutical applications of essential oils such as turmeric oil and lemongrass oil are well-known, and their active components, ar-turmerone and citral, respectively, are known for their antibacterial, antifungal, antioxidant, antimutagenic, and anticarcinogenic properties. However, these essential oils are unstable, volatile, and insoluble in water, which limits their use for new formulations. Therefore, this study focuses on developing a CS-AL nanocarrier for the encapsulation of essential oils. The effects of process parameters such as the effect of heat and the concentrations of AL and CS were investigated. Various physicochemical characterization techniques such as scanning electron microscopy, Fourier transform infrared spectroscopy, and ultraviolet-visible spectroscopy were performed. Results of characterization studies showed that 0.3 mg/mL AL and 0.6 mg/mL CS produced minimum-sized particles (<300 nm) with good stability. It was also confirmed that the oil-loaded nanocapsules were hemocompatible, suggesting their use for future biomedical and pharmaceutical applications. Furthermore, the antiproliferative activity of turmeric oil- and lemongrass oil-loaded nanocapsules was estimated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay in A549 cell lines and it was found that both the nanoformulations had significant antiproliferative properties than the bare oil. Copyright © 2015. Published by Elsevier B.V.

  4. Antimicrobial Lemongrass Essential Oil-Copper Ferrite Cellulose Acetate Nanocapsules.

    PubMed

    Liakos, Ioannis L; Abdellatif, Mohamed H; Innocenti, Claudia; Scarpellini, Alice; Carzino, Riccardo; Brunetti, Virgilio; Marras, Sergio; Brescia, Rosaria; Drago, Filippo; Pompa, Pier Paolo

    2016-04-20

    Cellulose acetate (CA) nanoparticles were combined with two antimicrobial agents, namely lemongrass (LG) essential oil and Cu-ferrite nanoparticles. The preparation method of CA nanocapsules (NCs), with the two antimicrobial agents, was based on the nanoprecipitation method using the solvent/anti-solvent technique. Several physical and chemical analyses were performed to characterize the resulting NCs and to study their formation mechanism. The size of the combined antimicrobial NCs was found to be ca. 220 nm. The presence of Cu-ferrites enhanced the attachment of LG essential oil into the CA matrix. The magnetic properties of the combined construct were weak, due to the shielding of Cu-ferrites from the polymeric matrix, making them available for drug delivery applications where spontaneous magnetization effects should be avoided. The antimicrobial properties of the NCs were significantly enhanced with respect to CA/LG only. This work opens novel routes for the development of organic/inorganic nanoparticles with exceptional antimicrobial activities.

  5. Polylactic Acid-Lemongrass Essential Oil Nanocapsules with Antimicrobial Properties.

    PubMed

    Liakos, Ioannis L; Grumezescu, Alexandru Mihai; Holban, Alina Maria; Florin, Iordache; D'Autilia, Francesca; Carzino, Riccardo; Bianchini, Paolo; Athanassiou, Athanassia

    2016-07-07

    Polylactic acid was combined with lemongrass essential oil (EO) to produce functional nanocapsules (NCs). The obtained polylactic acid nanoparticles showed antimicrobial activity both with and without the presence of lemongrass oil; however, the presence of EO improved the activity of the NCs. The presence of lemongrass assisted the formation of well-separated NCs and also provided enhanced antimicrobial properties, since lemongrass is known for its antimicrobial character. Fluorescence microscopy was used to optically observe the nanoparticles and NCs and revealed the attachment of lemongrass oil with the polylactic acid NCs. Dynamic light scattering was used to determine their size. UV absorption was used to determine the exact amount of lemongrass oil found in the polylactic acid-lemongrass oil NCs, which was important for understanding the minimum inhibitory concentration for the antimicrobial experiments. A series of clinically important microbial species were used in the study and the obtained NCs proved to have very good antimicrobial properties against all tested strains. Such NCs can be used for the design of ecological strategies, based on natural alternatives, which may be efficient against severe infections, including those that involve resistant pathogens and biofilms or those with difficult to reach localization.

  6. Polylactic Acid—Lemongrass Essential Oil Nanocapsules with Antimicrobial Properties

    PubMed Central

    Liakos, Ioannis L.; Grumezescu, Alexandru Mihai; Holban, Alina Maria; Florin, Iordache; D’Autilia, Francesca; Carzino, Riccardo; Bianchini, Paolo; Athanassiou, Athanassia

    2016-01-01

    Polylactic acid was combined with lemongrass essential oil (EO) to produce functional nanocapsules (NCs). The obtained polylactic acid nanoparticles showed antimicrobial activity both with and without the presence of lemongrass oil; however, the presence of EO improved the activity of the NCs. The presence of lemongrass assisted the formation of well-separated NCs and also provided enhanced antimicrobial properties, since lemongrass is known for its antimicrobial character. Fluorescence microscopy was used to optically observe the nanoparticles and NCs and revealed the attachment of lemongrass oil with the polylactic acid NCs. Dynamic light scattering was used to determine their size. UV absorption was used to determine the exact amount of lemongrass oil found in the polylactic acid—lemongrass oil NCs, which was important for understanding the minimum inhibitory concentration for the antimicrobial experiments. A series of clinically important microbial species were used in the study and the obtained NCs proved to have very good antimicrobial properties against all tested strains. Such NCs can be used for the design of ecological strategies, based on natural alternatives, which may be efficient against severe infections, including those that involve resistant pathogens and biofilms or those with difficult to reach localization. PMID:27399724

  7. Vegetable Oil-Loaded Nanocapsules: Innovative Alternative for Incorporating Drugs for Parenteral Administration.

    PubMed

    Venturinil, C G; Bruinsmann, A; Oliveira, C P; Contri, R V; Pohlmann, A R; Guterres, S S

    2016-02-01

    An innovative nanocapsule formulation for parenteral administration using selected vegetable oils (mango, jojoba, pequi, oat, annatto, calendula, and chamomile) was developed that has the potential to encapsulate various drugs. The vegetable oil-loaded nanocapsules were prepared by interfacial deposition and compared with capric/caprylic triglyceride-loaded lipid core nanocapsules. The major objective was to investigate the effect of vegetable oils on particle size distribution and physical stability and to determine the hemolytic potential of the nanocapsules, considering their applicability for intravenous administration. Taking into account the importance of accurately determining particle size for the selected route of administration, different size characterization techniques were employed, such as Laser Diffraction, Dynamic Light Scattering, Multiple Light Scattering, Nanoparticle Tracking Analysis, and Transmission Electronic Microscopy. Laser diffraction studies indicated that the mean particle size of all nanocapsules was below 300 nm. For smaller particles, the laser diffraction and multiple light scattering data were in agreement (D[3,2]-130 nm). Dynamic light scattering and nanoparticle tracking analysis, two powerful techniques that complement each other, exhibited size values between 180 and 259 nm for all nanoparticles. Stability studies demonstrated a tendency of particle creaming for jojoba-nanocapsules and sedimentation for the other nanoparticles; however, no size variation occurred over 30 days. The hemolysis test proved the hemocompatibility of all nanosystems, irrespective of the type of oil. Although all developed nanocapsules presented the potential for parenteral administration, jojoba oil-loaded nanocapsules were selected as the most promising nanoformulation due to their low average size and high particle size homogeneity.

  8. Halloysite Nanocapsules Containing Thyme Essential Oil: Preparation, Characterization, and Application in Packaging Materials.

    PubMed

    Jang, Si-Hoon; Jang, So-Ri; Lee, Gyeong-Min; Ryu, Jee-Hoon; Park, Su-Il; Park, No-Hyung

    2017-09-01

    Halloysite nanotubes (HNTs), which are natural nanomaterials, have a hollow tubular structure with about 15 nm inner and 50 nm outer diameters. Because of their tubular shape, HNTs loaded with various materials have been investigated as functional nanocapsules. In this study, thyme essential oil (TO) was encapsulated successfully in HNTs using vacuum pulling methods, followed by end-capping or a layer-by-layer surface coating process for complete encapsulation. Nanocapsules loaded with TO were mixed with flexographic ink and coated on a paper for applications as food packaging materials. Scanning electron microscopy and transmission electron microscopy were used to characterize the morphology of the nanocapsules and to confirm the TO loading of the nanocapsules. Fourier transform infrared spectroscopy and thermogravimetric analyses analysis were used to complement the structural information. In addition, the controlled release of TO from the nanocapsules showed sustained release properties over a period of many days. The results reveal that the release properties of TO in these nanocapsules could be controlled by surface modifications such as end-capping and/or surface coating of bare nanocapsules. The packaging paper with TO-loaded HNT capsules was effective in eliminating against Escherichia coli during the first 5 d and showed strong antibacterial activity for about 10 d. © 2017 Institute of Food Technologists®.

  9. Nanocapsules Containing Neem (Azadirachta Indica) Oil: Development, Characterization, And Toxicity Evaluation.

    PubMed

    Pasquoto-Stigliani, Tatiane; Campos, Estefânia V R; Oliveira, Jhones L; Silva, Camila M G; Bilesky-José, Natalia; Guilger, Mariana; Troost, Johann; Oliveira, Halley C; Stolf-Moreira, Renata; Fraceto, Leonardo F; de Lima, Renata

    2017-07-19

    In this study, we prepared, characterized, and performed toxicity analyses of poly(ε-caprolactone) nanocapsules loaded with neem oil. Three formulations were prepared by the emulsion/solvent evaporation method. The nanocapsules showed a mean size distribution around 400 nm, with polydispersity below 0.2 and were stable for 120 days. Cytotoxicity and genotoxicity results showed an increase in toxicity of the oleic acid + neem formulations according to the amount of oleic acid used. The minimum inhibitory concentrations demonstrated that all the formulations containing neem oil were active. The nanocapsules containing neem oil did not affect the soil microbiota during 300 days of exposure compared to the control. Phytotoxicity studies indicated that NC_20 (200 mg of neem oil) did not affect the net photosynthesis and stomatal conductance of maize plants, whereas use of NC_10 (100:100 of neem:oleic acid) and NC_15 (150:50 of neem:oleic acid) led to negative effects on these physiological parameters. Hence, the use of oleic acid as a complement in the nanocapsules was not a good strategy, since the nanocapsules that only contained neem oil showed lower toxicity. These results demonstrate that evaluation of the toxicity of nanopesticides is essential for the development of environmentally friendly formulations intended for applications in agriculture.

  10. Antifungal activity of nanocapsule suspensions containing tea tree oil on the growth of Trichophyton rubrum.

    PubMed

    Flores, F C; de Lima, J A; Ribeiro, R F; Alves, S H; Rolim, C M B; Beck, R C R; da Silva, Cristiane Bona

    2013-04-01

    The aim of this study was to evaluate, for the first time, the antifungal efficacy of nanocapsules and nanoemulsions containing Melaleuca alternifolia essential oil (tea tree oil) in an onychomycosis model. The antifungal activity of nanostructured formulations was evaluated against Trichophyton rubrum in two different in vitro models of dermatophyte nail infection. First, nail powder was infected with T. rubrum in a 96-well plate and then treated with the formulations. After 7 and 14 days, cell viability was verified. The plate counts for the samples were 2.37, 1.45 and 1.0 log CFU mL(-1) (emulsion, nanoemulsion containing tea tree oil and nanocapsules containing tea tree oil, respectively). A second model employed nails fragments which were infected with the microorganism and treated with the formulations. The diameter of fungal colony was measured. The areas obtained were 2.88 ± 2.08 mm(2), 14.59 ± 2.01 mm(2), 40.98 ± 2.76 mm(2) and 38.72 ± 1.22 mm(2) for the nanocapsules containing tea tree oil, nanoemulsion containing tea tree oil, emulsion and untreated nail, respectively. Nail infection models demonstrated the ability of the formulations to reduce T. rubrum growth, with the inclusion of oil in nanocapsules being most efficient.

  11. Enhanced photostability, radical scavenging and antitumor activity of indole-3-carbinol-loaded rose hip oil nanocapsules.

    PubMed

    Gehrcke, Mailine; Giuliani, Laura Minussi; Ferreira, Luana Mota; Barbieri, Allanna Valentini; Sari, Marcel Henrique Marcondes; da Silveira, Elita Ferreira; Azambuja, Juliana Hofstatter; Nogueira, Cristina Wayne; Braganhol, Elizandra; Cruz, Letícia

    2017-05-01

    This study aimed to develop poly(ε-caprolactone) nanocapsules loaded with indole-3-cabinol (I3C) using rose hip oil (RHO) or medium chain triglycerides (MCT) as oil core. In vitro radical scavenging activity (DPPH method), hemolysis, and antitumor effects on breast (MCF-7) and glioma (C6) cells were conducted. Preformulation evaluations revealed that RHO is suitable to prepare the nanocapsules considering the log P determination and dissolution/swelling experiments of polymer films. The nanocapsules were prepared and presented adequate physicochemical characteristics as mean size around 250nm, polydispersity index values <0.2, zeta potential negative values and I3C encapsulation efficiency around 42%, without any influence of the oil core (RHO or MCT) on these parameters. However, the photodegradation study demonstrated that RHO nanocapsules showed less degree of I3C degradation in comparison to MCT nanocapsules. The in vitro release profile showed that both nanocapsule suspensions demonstrated an initial burst effect followed by a prolonged I3C release. In addition, the formulations were considered hemocompatibles at 10μg/mL and showed an enhanced radical scavenging activity in comparison to free I3C. Moreover, nanocapsules prepared with RHO increased about two times the antitumor effect of I3C on MCF-7 and C6 cells without significant reduction of astrocyte cell viability. In conclusion, nanocapsule formulations developed in this study might be considered promising for cancer treatment. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Olive-oil nanocapsules stabilized by HSA: influence of processing variables on particle properties

    NASA Astrophysics Data System (ADS)

    Molina-Bolívar, J. A.; Galisteo-González, F.

    2015-10-01

    Liquid lipid nanocapsules (LLN) are considered to be promising drug carriers in the medical field. The size and the surface charge of these nanocarriers are of major importance, affecting their bioavailability and the in vivo behaviour after intravenous injection. This research provides a comprehensive study on the preparation of olive-oil nanocapsules stabilized with a human serum albumin shell (HSA). LLN were prepared by modified solvent-displacement method. Numerous experimental variables were examined in order to characterize their impact on LLN size, distribution, and electrophoretic mobility. Physicochemical parameters of LLN were controlled by adjusting the nanodroplet stabilizing shell of adsorbed protein molecules, which was affected by the oil:HSA ratio, pH, and ionic strength of aqueous medium. The stronger the repulsion between adsorbed HSA molecules, the smaller and more monodisperse the particles proved. Other process parameters, including the ethanol:acetone ratio, organic:aqueous phase ratio, speed of organic-phase injection, and stirring rate were examined to achieve optimum preparation conditions. LLN produced by our standardized formulation were in the range of 170-175 nm with low polydispersity index (<0.1). Long-term colloidal stability of samples was evaluated after 6 months of storage. Efficient incorporation of curcumin, a model for a water-insoluble drug, into olive-oil nanocapsules was achieved (90 %). Encapsulation of curcumin into LLN had a stabilizing effect with respect to drug photodecomposition compared to that of the free molecule in solution.

  13. Association of Borage Oil and Betamethasone Dipropionate in Lipid-Core Nanocapsules: Characterization, Photostability and In Vitro Irritation Test.

    PubMed

    Weber, Julia; Funk, Nadine L; Motta, Mariana H; Guedes, Alessandra M; Visintainer, Ana Paula C; Tedesco, Solange B; Da Silva, Cristiane de B

    2016-02-01

    The association of vegetable products to nanostructured systems has attracted the attention of researchers due to several advantages, such as drug photoprotection, as well as the improvement of the pharmacological and therapeutic activities because of synergistic action, which can provide their topical application. In this work, lipid-core nanocapsules containing borage oil as oil core and betamethasone dipropionate were developed, and nanocapsules without the drug were prepared for comparison. The suspensions were characterized in relation to mean particle size, zeta potential, pH, drug content, and encapsulation efficiency. A photodegradation study was carried out and the in vitro release profile as well as the irritation potential of the drug after nanoencapsulation were also evaluated. In addition, the antiproliferative activity of the free borage oil as well as loaded in nanocapsules was studied. Lipid-core nanocapsules showed nanometric mean size (185-210 nm); polydispersity index below 0.10; negative zeta potential and pH slightly acid (6.0-6.2). Moreover, the drug content was close to theoretical concentration (0.50 +/- 0.03 mg/ml of betamethasone), and the encapsulation efficiency was approximately 100%. The study of the antiproliferative activity of borage oil showed ability to reduce cell growth of Allium cepa. The nanoencapsulation of betamethasone dipropionate provided greater protection against UVC light and decreased the irritation potential of the drug. The release profile of betamethasone dipropionate from nanocapsules followed monoexponential model.

  14. Formulation and in vitro evaluation of coconut oil-core cationic nanocapsules intended for vaginal delivery of clotrimazole.

    PubMed

    Santos, Sara S; Lorenzoni, Alessandra; Pegoraro, Natháli S; Denardi, Laura B; Alves, Sydney H; Schaffazick, Scheila R; Cruz, Letícia

    2014-04-01

    The objective of this work was to propose coconut oil-core nanocapsules prepared from Eudragit(®) RS100, a cationic polymer, and to evaluate their potential for vaginal delivery of clotrimazole in candidiasis. Nanocapsule suspensions loaded with clotrimazole at 1.0 and 3.0mg/mL were prepared by interfacial deposition of Eudragit(®) RS100. The physicochemical characterization showed average diameter lower than 200 nm, low polydispersity index, positive zeta potential (+10.94 to +14.57 mV), acid pH values (5.4-5.7) and encapsulation efficiencies close to 100%. After 60 days of storage at room temperature and protected from light, the nanocapsules were reasonably stable. Photodegradation studies showed that nanoencapsulation improved clotrimazole stability against UV radiation. The in vitro drug release at pH 4.5 was characterized by a prolonged release with no burst effect. The nanocapsules were more active than free clotrimazole against Candida albicans and Candida glabrata strains susceptible and resistant to fluconazole. Hence, clotrimazole-loaded coconut oil-core nanocapsules represent promising alternatives to the treatment of vulvovaginal candidiasis.

  15. Oil-encapsulating PEO-PPO-PEO/PEG shell cross-linked nanocapsules for target-specific delivery of paclitaxel.

    PubMed

    Bae, Ki Hyun; Lee, Yuhan; Park, Tae Gwan

    2007-02-01

    PEO-PPO-PEO/PEG shell cross-linked nanocapsules encapsulating an oil phase in their nanoreservoir structure was developed as a target-specific carrier for a water-insoluble drug, paclitaxel. Oil-encapsulating PEO-PPO-PEO/PEG composite nanocapsules were synthesized by dissolving an oil (Lipiodol) and an amine-reactive PEO-PPO-PEO derivative in dichloromethane and subsequently dispersing in an aqueous solution containing amine-functionalized six-arm-branched poly(ethylene glycol) by ultrasonication. The resultant shell cross-linked nanocapsules had a unique core/shell architecture with an average size of 110.7 +/- 9.9 nm at 37 degrees C, as determined by dynamic light scattering and transmission electron microscopy. Paclitaxel could be effectively solubilized in the inner Lipiodol phase surrounded by a cross-linked PEO-PPO-PEO/PEG shell layer. The paclitaxel-loaded nanocapsules were further conjugated with folic acid to achieve folate receptor targeted delivery. Confocal microscopy and flow cytometric analysis revealed that folate-mediated targeting significantly enhanced the cellular uptake and apoptotic effect against folate receptor overexpressing cancer cells. The present study suggested that these novel nanomaterials encapsulating an oil reservoir could be potentially applied for cancer cell targeted delivery of various water-insoluble therapeutic and diagnostic agents.

  16. Release study and inhibitory activity of thyme essential oil-loaded chitosan nanoparticles and nanocapsules against foodborne bacteria.

    PubMed

    Sotelo-Boyás, M; Correa-Pacheco, Z; Bautista-Baños, S; Gómez Y Gómez, Y

    2017-10-01

    The antibacterial property of thyme essential oil due to different volatile compounds, has been well documented in the literature. To overcome the high volatility of essential oil components, encapsulation has emerged as a new alternative. In this work, chitosan and thyme essential oil-loaded chitosan nanoparticles (TEO-CSNPs) and nanocapsules (TEO-CSNCs) were prepared by nanoprecipitation and nanoencapsulation, respectively. The morphology, encapsulation efficiency, release kinetics, and inhibitory activity were evaluated. Average size of nanocapsules (9.1±1.6nm) was slightly higher than nanoparticles (6.4±0.5nm). The percentage encapsulation of thymol and carvacrol, more than 68%, was similar for nanoparticles and nanocapsules. However, thymol and carvacrol release time from TEO-CSNPs was faster compared to TEO-CSNCs. The release kinetics data were fitted to three analytical kinetic models with no statistical differences among them. The inhibitory activity was higher for nanoparticles than for nanocapsules when tested against six foodborne bacteria. The inhibitory effect of TEO-CSNPs was the highest against Staphylococcus aureus (inhibition halo 4.3cm) and for TEO-CSNCs it was against Bacillus cereus (inhibition halo 1.9cm). Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Hydrogels Containing Nanocapsules and Nanoemulsions of Tea Tree Oil Provide Antiedematogenic Effect and Improved Skin Wound Healing.

    PubMed

    Flores, Fernanda C; De Lima, Julia A; Da Silva, Cássia R; Benvegnú, Dalila; Ferreira, Juliano; Burger, Marilise E; Beck, Ruy C R; Rolim, Clarice M B; Rocha, Maria Isabel U M; Da Veiga, Marcelo L; Da Silva, Cristiane de B

    2015-01-01

    In previous works, we developed nanocapsules and nanoemulsions containing the tea tree oil. The aim of this work was to prepare and characterize hydrogels containing these nanocarriers, and to evaluate their in vivo efficacy in protecting skin damage induced by UVB and cutaneous wound healing. Hydrogels were prepared using Carbopol Ultrez and their physicochemical characteristics were evaluated: macroscopic analysis, pH, spreadability and rheological properties. The in vivo antiedematogenic effect was evaluated by ear thickness measurement after UVB-irradiation. In order to evaluate healing action of hydrogels, we investigated the regression of the cutaneous lesion in rats. Hydrogels showed homogeneous aspect and pH values between 5.6-5.8 and a non-Newtonian behavior. The presence of nanocapsules and nanoemulsions in hydrogels did not change their spreadability profile. The inclusion of tea tree oil in the nanocapsules and nanoemulsions allowed reducing the edema induced by UVB exposure. Hydrogel containing nanocapsules presented a higher reduction of the wound area compared to the hydrogel containing nanoemulsions and hydrogel containing allantoin. This study shows the feasibility of obtained dermatological formulations containing the tea tree oil associated in nanostructured systems. These formulations represent a promising approach to topical treatment of inflammatory disorders and wound healing.

  18. Hydrogel containing silibinin-loaded pomegranate oil based nanocapsules exhibits anti-inflammatory effects on skin damage UVB radiation-induced in mice.

    PubMed

    Marchiori, Marila Crivellaro Lay; Rigon, Cristina; Camponogara, Camila; Oliveira, Sara Marchesan; Cruz, Letícia

    2017-05-01

    The present study shows the development of a topical formulation (hydrogel) containing silibinin-loaded pomegranate oil based nanocapsules suspension and its evaluation as an alternative for the treatment of cutaneous UVB radiation-induced damages. For this, an animal model of skin injury induced by UVB radiation was employed. Gellan gum was used as gel forming agent by its direct addition to nanocapsules suspension. The hydrogels showed adequate pH values (5.6-5.9) and a silibinin content close to the theoretical value (1mg/g). Through vertical Franz diffusion cells it was demonstrated that nanocapsules decreased the silibinin retention in the semisolid formulation. All formulations were effective in reducing mice ear edema and leukocyte infiltration induced by UVB radiation 24h after the treatments. After 48h, only the hydrogels containing nanocapsules or silibinin associated with pomegranate oil demonstrated anti-edematogenic effect, as well as the positive control (hydrogel containing silver sulfadiazine 1%). After 72h, the hydrogel containing unloaded pomegranate oil based nanocapsules still presented a small activity. In conclusion, the results of this investigation demonstrated the feasibility to prepare a semisolid formulation presenting performance comparable to the traditional therapeutic option for skin burns (silver sulfadiazine) and with prolonged in vivo anti-inflammatory activity compared to the non-nanoencapsulated compounds. Copyright © 2017. Published by Elsevier B.V.

  19. Synergistic interactions between doxycycline and terpenic components of essential oils encapsulated within lipid nanocapsules against gram negative bacteria.

    PubMed

    Valcourt, C; Saulnier, P; Umerska, A; Zanelli, M P; Montagu, A; Rossines, E; Joly-Guillou, M L

    2016-02-10

    The combination of essential oils (EOs) with antibiotics provides a promising strategy towards combating resistant bacteria. We have selected a mixture of 3 major components extracted from EOs: carvacrol (oregano oil), eugenol (clove oil) and cinnamaldehyde (cinnamon oil). These compounds were successfully encapsulated within lipid nanocapsules (LNCs). The EOs-loaded LNCs were characterised by a noticeably high drug loading of 20% and a very small particle diameter of 114nm. The in vitro interactions between EOs-loaded LNCs and doxycycline were examined via checkerboard titration and time-kill assay against 5 Gram-negative strains: Acinetobacter baumannii SAN, A. baumannii RCH, Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa. No growth inhibition interactions were found between EOs-loaded LNCs and doxycycline (FIC index between 0.7 and 1.30). However, when bactericidal effects were considered, a synergistic interaction was observed (FBC index equal to 0.5) against all tested strains. A synergistic effect was also observed in time-kill assay (a difference of at least 3 log between the combination and the most active agent alone). Scanning electron microscopy (SEM) was used to visualise the changes in the bacterial membrane. The holes in bacterial envelope and leakage of cellular contents were observed in SE micrographs after exposure to the EOs-LNCs and the doxycycline combination.

  20. Synthesis of Oil-Laden Poly(ethylene glycol) Diacrylate Hydrogel Nanocapsules from Double Nanoemulsions.

    PubMed

    Zhang, Mengwen; Nowak, Maksymilian; Malo de Molina, Paula; Abramovitch, Michael; Santizo, Katherine; Mitragotri, Samir; Helgeson, Matthew E

    2017-06-20

    Multiple emulsions have received great interest due to their ability to be used as templates for the production of multicompartment particles for a variety of applications. However, scaling these complex droplets to nanoscale dimensions has been a challenge due to limitations on their fabrication methods. Here, we report the development of oil-in-water-in-oil (O1/W/O2) double nanoemulsions via a two-step high-energy method and their use as templates for complex nanogels comprised of inner oil droplets encapsulated within a hydrogel matrix. Using a combination of characterization methods, we determine how the properties of the nanogels are controlled by the size, stability, internal morphology, and chemical composition of the nanoemulsion templates from which they are formed. This allows for identification of compositional and emulsification parameters that can be used to optimize the size and oil encapsulation efficiency of the nanogels. Our templating method produces oil-laden nanogels with high oil encapsulation efficiencies and average diameters of 200-300 nm. In addition, we demonstrate the versatility of the system by varying the types of inner oil, the hydrogel chemistry, the amount of inner oil, and the hydrogel network cross-link density. These nontoxic oil-laden nanogels have potential applications in food, pharmaceutical, and cosmetic formulations.

  1. Oxidative stability of red palm oils blended chicken nuggets during frozen storage

    NASA Astrophysics Data System (ADS)

    Kamaruzaman, Nurkhuzaiah; Babji, Abdul Salam

    2014-09-01

    The effects of red palm oils known as Naturally Vitamin Rich Oil (NVRO) on the lipid stability of chicken nuggets were determined. Lipid oxidation was analyzed during frozen storage (-18 °C) for up to 4 months. Thiobarbituric acid (TBA) values and peroxide value (PV) for all samples chicken nuggets increased throughout 3 months of frozen storage and then start to decrease thereafter. Chicken nuggets formulated with NVRO, NVRO-100 and NVRO-50 showed lower TBA values and PV compared to the samples prepared with chicken fat. However, among NVRO, there were not significantly different for most of the months. It was concluded that the utilization of red palm oils in chicken nuggets significantly reduced the oxidation of lipid, which was indicated by the PV throughout 4 months of frozen storage.

  2. Influence of the type of vegetable oil on the drug release profile from lipid-core nanocapsules and in vivo genotoxicity study.

    PubMed

    Rigo, Lucas Almeida; Frescura, Viviane; Fiel, Luana; Coradini, Karine; Ourique, Aline Ferreira; Emanuelli, Tatiana; Quatrin, Andréia; Tedesco, Solange; Silva, Cristiane B da; Guterres, Silvia Staniçuaski; Pohlmann, Adriana Raffin; Beck, Ruy Carlos Ruver

    2014-11-01

    The use of rice bran (RB), soybean (SB) or sunflower seed (SF) oils to prepare lipid-core nanocapsules (LNCs) as controlled drug delivery systems was investigated. LNCs were prepared by interfacial deposition using the preformed polymer method. All formulations showed negative zeta potential and adequate nanotechnological characteristics (particle size 220-230  nm, polydispersity index < 0.20). The environmental safety was evaluated through an in vivo protocol (Allium cepa test) and LNCs containing RB, SB or SF oils did not present genotoxic potential. Clobetasol propionate (CP) was selected as a model drug to evaluate the influence of the type of vegetable oil on the control of the drug release from LNCs. Biphasic drug release profiles were observed for all formulations. After 168  h, the concentration of drug released from the formulation containing SF oil was lower (0.36  mg/mL) than from formulations containing SB (0.40  mg/mL) or RB oil (0.45  mg/mL). Good correlations between the consistency indices for the LNC cores and the burst and sustained drug release rate constants were obtained. Therefore, the type of the vegetal oil was shown as an important factor governing the control of drug release from LNCs.

  3. Oleophobicity of Biomimetic Micropatterned Surface and Its Effect on the Adhesion of Frozen Oil.

    PubMed

    Pan, Zihe; Zhang, Wei; Kowalski, Andrew; Zhao, Boxin

    2015-09-15

    The relationship between the oleophobicity of micropatterned surfaces and the reduction of oil adhesion at low temperatures was explored by using siloxane elastomer surfaces as a model system. Polydimethylsiloxane (PDMS) surfaces were fabricated with varying oleophobicity from oleophilic to superoleophobic by combing the blending of trichloro(1H,1H,2H,2H-perfluorooctyl)silane (FDTS) into PDMS with the construction of bioinspired micropillars. The oil contact angles of micropillars were >130°, with the largest contact angle measured to be 146°. The micropillared surface showed remarkable self-cleaning properties; the contact angle hysteresis was <15°. The transparent oil droplets on PDMS surfaces of varied oleophobicity were frozen into a white-colored solid at -25 °C with the aid of a cooling system. Adhesion forces of the frozen oil droplets were obtained from the knock-off tests, showing that the adhesion forces dropped with the increased oleophobicity. The largest adhesion force was observed on the oleophilic flat surface, while the lowest adhesion force was on the highest oleophobic micropillared surface. The relative effectiveness of chemical and physical modifications on adhesion strength reduction was studied in terms of FDTS and micropillars, respectively. The results showed that a reduction of adhesion strength by 4% was reached by blending FDTS into flat PDMS, while a much more pronounced reduction of frozen oil adhesion strength by 60% was achieved by blending FDTS into PDMS micropillars; these results suggested a possible synergic effect of the FDTS chemistry and micropillar on the reduction of adhesion strength of frozen oil droplets.

  4. Olive Oil Based Emulsions in Frozen Puff Pastry Production

    NASA Astrophysics Data System (ADS)

    Gabriele, D.; Migliori, M.; Lupi, F. R.; de Cindio, B.

    2008-07-01

    Puff pastry is an interesting food product having different industrial applications. It is obtained by laminating layers of dough and fats, mainly shortenings or margarine, having specific properties which provides required spreading characteristic and able to retain moisture into dough. To obtain these characteristics, pastry shortenings are usually saturated fats, however the current trend in food industry is mainly oriented towards unsatured fats such as olive oil, which are thought to be safer for human health. In the present work, a new product, based on olive oil, was studied as shortening replacer in puff pastry production. To ensure the desired consistency, for the rheological matching between fat and dough, a water-in-oil emulsion was produced based on olive oil, emulsifier and a hydrophilic thickener agent able to increase material structure. Obtained materials were characterized by rheological dynamic tests in linear viscoelastic conditions, aiming to setup process and material consistency, and rheological data were analyzed by using the weak gel model. Results obtained for tested emulsions were compared to theological properties of a commercial margarine, adopted as reference value for texture and stability. Obtained emulsions are characterized by interesting rheological properties strongly dependent on emulsifier characteristics and water phase composition. However a change in process temperature during fat extrusion and dough lamination seems to be necessary to match properly typical dough rheological properties.

  5. Function of ram spermatozoa frozen in diluents supplemented with casein and vegetable oils.

    PubMed

    Del Valle, I; Souter, A; Maxwell, W M C; Muiño-Blanco, T; Cebrián-Pérez, J A

    2013-05-01

    The aim of this study was to assess biologically safer components as alternatives to egg yolk for the frozen storage of ram semen using casein, coconut or palm oil in either Salamon's diluent (S) or a swim-up medium (SU). Ejaculates were frozen as pellets and sperm motility (subjectively) and acrosome integrity (FITC-PNA/PI) by flow cytometry were assessed at 0, 3 and 6h after thawing and incubation at 37°C. Three experiments were done: different concentrations of palm oil (5%, 10% and 20%); casein added as emulsifier and protective agent; and differences between egg yolk, coconut and palm oil in S and SU. 20% of oil added to SU accounted for a lesser percentage (P<0.05) of motile cells compared to rest while no differences were found between different oil levels on viable cells. When casein was added to diluents containing 5% of palm oil, no differences were found between palm or casein (P>0.05). No differences were found when S and SU were compared neither as groups nor between S alone and containing coconut or palm oil; however, SU alone yielded less motility than SU 5% coconut. However, in both groups, S and SU, egg yolk accounted for the greatest values in both bases. These results indicate that none of biologically safer media components (casein, palm or coconut oil) used in this study maintained the function of ram spermatozoa after freeze-thawing better than S-containing egg yolk. The application of vegetable oils as substitutes for egg yolk in diluents for the cryopreservation of ram spermatozoa requires further research. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Effect of the treatment with Achyrocline satureioides (free and nanocapsules essential oil) and diminazene aceturate on hematological and biochemical parameters in rats infected by Trypanosoma evansi.

    PubMed

    Do Carmo, Guilherme M; Baldissera, Matheus D; Vaucher, Rodrigo A; Rech, Virginia Cielo; Oliveira, Camila B; Sagrillo, Michele Rorato; Boligon, Aline A; Athayde, Margareth L; Alves, Marta P; França, Raqueli T; Lopes, Sonia T A; Schwertz, Claiton I; Mendes, Ricardo E; Monteiro, Silvia G; Da Silva, Aleksandro S

    2015-02-01

    This study aimed to verify the effect of the treatment with A. satureioides essential oil (free and nanoencapsulated forms) and diminazene aceturate on hematological and biochemical variables in rats infected by Trypanosoma evansi. The 56 rats were divided into seven groups with eight rats each. Groups A, C and D were composed by uninfected animals, and groups B, E, F and G were formed by infected rats with T. evansi. Rats from groups A and B were used as negative and positive control, respectively. Rats from the groups C and E were treated with A. satureioides essential oil, and groups D and F were treated with A. satureioides nanoencapsulated essential oil. Groups C, D, E and F received one dose of oil (1.5 mL kg(-1)) during five consecutive days orally. Group G was treated with diminazene aceturate (D.A.) in therapeutic dose (3.5 mg kg(-1)) in an only dose. The blood samples were collected on day 5 PI for analyses of hematological (erythrocytes and leukocytes count, hemoglobin concentration, hematocrit, mean corpuscular and mean corpuscular hemoglobin concentration) and biochemical (glucose, triglycerides, cholesterol, alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, urea and creatinine) variables. A. satureioides administered was able to maintain low parasitemia, mainly the nanoencapsulated form, on 5 days post infection. On the infected animals with T. evansi treated with A. satureioides essential oil (free and nanocapsules) the number of total leucocytes, lymphocytes and monocytes present was similar to uninfected rats, and different from infected and not-treated animals (leukocytosis). Treatment with A. satureioides in free form elevated levels of ALT and AST, demonstrating liver damage; however, treatment with nanoencapsulated form did not cause elevation of these enzymes. Finally, treatments inhibited the increase in creatinine levels caused by infection for T. evansi. In summary, the nanoencapsulated

  7. Scale-up of polyamide and polyester Parsol® MCX nanocapsules by interfacial polycondensation and solvent diffusion method.

    PubMed

    Stumpo, Marianna; Anselmi, Cecilia; Vauthier, Christine; Mitri, Khalil; Hanno, Ibrahim; Huang, Nicolas; Bouchemal, Kawthar

    2013-10-01

    The scale-up of oil-containing polyamide nanocapsules produced by simultaneous interfacial polycondensation and solvent diffusion was successfully achieved. Up to 1,500 mL were produced by using a Y-shaped mixer device. The sizes of nanocapsules containing olive oil were modulated from 646 to 211 nm by changing process parameters without modification of the formulation composition. All the results of nanocapsule diameters (dsc) expressed as a function of the Reynolds number (Re) showed the existence of a typical power-law relationship. It was demonstrated that the high turbulences created upon nanocapsule formation are the most important parameter allowing to nanocapsule size to be controlled without modifying the formulation composition. Finally, the power-law relationship was used to predict the size of nanocapsules composed of polyamide or polyester and loaded with Parsol(®) MCX. The physico-chemical properties of both polyamide and polyester nanocapsules at the laboratory scale were compared to the ones obtained at the pilot scale. The encapsulation efficiency was higher than 98% in both types of nanocapsules at the laboratory and the pilot scales. The in vitro releases of Parsol(®) MCX from polyester nanocapsules were reproducible at both scales. This is the first time such a power-law was described for the preparation of nanocapsules by interfacial polycondensation and solvent diffusion.

  8. Physical properties of a frozen yogurt fortified with a nano-emulsion containing purple rice bran oil

    USDA-ARS?s Scientific Manuscript database

    The objectives of this study were to develop and evaluate a frozen yogurt (FY) fortified with a nano-emulsion containing purple rice bran oil (NPRBO). A nano-emulsion with a droplet size range of 150-300 nm was produced by sonication followed by ultra-shear homogenization. The nano-emulsion was mi...

  9. Cyclic fatty acid monomer formation in domestic frying of frozen foods in sunflower oil and high oleic acid sunflower oil without oil replenishment.

    PubMed

    Romero, A; Bastida, S; Sánchez-Muniz, F J

    2006-10-01

    During the frying process, oxidation, hydrolysis, polymerization, isomerization, and cyclization occur. Polymers and Cyclic fatty acid monomers (CFAM) are potentially toxic, and the latter are detected at relatively low levels (0.01-0.7%) in used frying oils. Twenty fryings of different frozen foods were carried out over 10 consecutive days in sunflower oil (SO) and in high oleic acid sunflower oil (HOSO). Fatty acid methyl ester derivates were hydrogenated with platinum oxide catalyst under hydrogen. Ethyl palmitate was added as an internal standard before hydrogenation. The CFAM obtained were isolated, concentrated and quantified by HPLC using a reverse-phase column followed by gas chromatography. Linear adjustments between total and individual CFAM content and the number of frying operations performed with both oils were established by analysis of variance. The comparison between linear equation adjustments of both oils was performed by a two-way analysis of covariance. After 20 fryings 15.4 +/- 0.06 g polar content/100 g oil, 7.15 +/- 0.08 g polymers/ oil, 11.52 +/- 0.08 g polymers/100g oil and 855 +/- 8.9 mg CFAM/kg oil were detected in SO. A 10 mg/100 mg oil of altered fatty acid content correspond to 700 mg/kg CFAM, while 25% polar material and 10% polymer content would correspond to about 850-1,000 mg CFAM/kg oil. Data suggest that frying with SO produces in each new frying 9 mg CFAM/kg more than frying with HOSO (p < 0.001). After frying cyclopentyl structures were more than twice as abundant as cyclohexyl fatty acids in both oils. Bicyclic compound formation was significantly higher in SO (p < 0.001). Because digestion and absorption of polar material, polymers and CFAM occur, data clearly show the advantageousness and advisability of frying with HOSO rather than SO.

  10. Preparation of polyamide nanocapsules of Aloe vera L. delivery with in vivo studies.

    PubMed

    Esmaeili, Akbar; Ebrahimzadeh, Maryam

    2015-04-01

    Aloe vera is the oldest medicinal plant ever known and the most applied medicinal plant worldwide. The purpose of this study was to prepare polyamide nanocapsules containing A. vera L. by an emulsion diffusion technique with in vivo studies. Diethyletriamine (DETA) was used as the encapsulating polymer with acetone ethyl acetate and dimethyl sulfoxide (DMSO) as the organic solvents and Tween and gelatin in water as the stabilizers. Sebacoyl chloride (SC) monomer, A. vera L. extract, and olive oil were mixed with the acetone and then water containing DETA monomer was added to the solution using a magnetic stirrer. Finally, the acetone was removed under vacuum, and nanocapsules were obtained using a freeze drier. This study showed that the size of the nanocapsule depends on a variety of factors such as the ratio of polymer to oil, the concentration of polymers, and the plant extract. The first sample is without surfactant and the size of nanocapsules in the sample is 115 nm. By adding surfactant, nanocapsules size was reduced to 96 nm. Nanocapsules containing A. vera were administered to rats and the effects were compared with a normal control group. The results showed that in the A. vera group, the effect is higher. The nanocapsules were identified by scanning electron microscopy (SEM), zeta potential sizer (ZPS), and Fourier-transform infrared spectroscopy (FT-IR).

  11. Effect of O/W process parameters on Crataegus azarolus L nanocapsule properties.

    PubMed

    Esmaeili, Akbar; Rahnamoun, Soraya; Sharifnia, Fariba

    2013-05-29

    Nanocapsules have many applications in the drug, cosmetic, fragrance, and food industries. In this study, Crataegus azarolus L. nanocapsules were prepared by a modified emulsion diffusion technique. In this technique a shell was first made from the polyester triblock copolymer poly(ethylene glycol)-poly(butylene adipate)-poly(ethylene glycol) (PEG-PBA-PEG) and then olive oil was set as the core of the nanocapsule by a method known as the polymer deposition solvent evaporation method. Varying amounts of C. azarolus extract, polymer, and olive oil were mixed in acetone and then added to water on a shaker. Finally, the acetone was removed by vacuuming. The size of the prepared nanocapsules were measured with a particle size analysis report (PSAR) and identified by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR). Our experiments showed that the size of the nanocapsules depends on the preparation conditions, i.e., the ratio of polymer to oil and concentrations of polymer and plant extract. A ratio of 1:0.25 polymer to oil was shown to be more suitable for the formation of smaller nanocapsules of C. azarolus.

  12. Effect of O/W process parameters on Crataegus azarolus L nanocapsule properties

    PubMed Central

    2013-01-01

    Background Nanocapsules have many applications in the drug, cosmetic, fragrance, and food industries. In this study, Crataegus azarolus L. nanocapsules were prepared by a modified emulsion diffusion technique. Methods In this technique a shell was first made from the polyester triblock copolymer poly(ethylene glycol)-poly(butylene adipate)-poly(ethylene glycol) (PEG-PBA-PEG) and then olive oil was set as the core of the nanocapsule by a method known as the polymer deposition solvent evaporation method. Varying amounts of C. azarolus extract, polymer, and olive oil were mixed in acetone and then added to water on a shaker. Finally, the acetone was removed by vacuuming. Results The size of the prepared nanocapsules were measured with a particle size analysis report (PSAR) and identified by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR). Conclusions Our experiments showed that the size of the nanocapsules depends on the preparation conditions, i.e., the ratio of polymer to oil and concentrations of polymer and plant extract. A ratio of 1:0.25 polymer to oil was shown to be more suitable for the formation of smaller nanocapsules of C. azarolus. PMID:23718829

  13. Oil-frozen W₁/O/W₂ double emulsions for dermal biomacromolecular delivery containing ethanol as chemical penetration enhancer.

    PubMed

    Jaimes-Lizcano, Yuly A; Lawson, Louise B; Papadopoulos, Kyriakos D

    2011-04-01

    Oil-frozen water-in-oil-in-water (W₁/O/W₂) double emulsions (DE) containing ethanol up to 40% (w/v) in the external aqueous W₂ phase exhibited external coalescence upon thawing of the oil phase, releasing up to 85% of the encapsulated protein of the internal aqueous phase. These emulsions were studied in vitro as potential dermal macromolecular delivery formulations, achieving fluorescein isothiocyanate-labeled bovine serum albumin (FITC-BSA) penetration of up to 86 μm into porcine skin, reaching the viable epidermis where the immunocompetent Langerhans cells are located. Enzyme-linked immunosorbent assay was performed to observe the effect of the emulsification process and ethanol content on the ability of BSA to form antigen-antibody complexes; results indicated that ethanol content and the emulsification process did not diminish the BSA-antibody complex formation when compared with a BSA standard aqueous solution. Therefore, it is shown that oil-frozen W₁/O/W₂ DE, with penetration-enhancing ethanol in the W₂ phase, can potentially be used for cutaneous vaccine delivery formulations. Copyright © 2010 Wiley-Liss, Inc.

  14. Nanocapsules templated on liquid cores stabilized by graft amphiphilic polyelectrolytes

    NASA Astrophysics Data System (ADS)

    Szafraniec, Joanna; Janik, Małgorzata; Odrobińska, Joanna; Zapotoczny, Szczepan

    2015-03-01

    A surfactant-free method of preparation of nanocapsules templated on liquid cores using amphiphilic graft polyelectrolytes was developed. A model photoactive copolymer, poly(sodium 2-acrylamido-2-methyl-1-propanesulfonate) with grafted poly(vinylnaphthalene) chains (PAMPS-graft-PVN) was used to stabilize toluene droplets in an aqueous emulsion. The macromolecules, due to their amphiphilic character and the presence of strong ionic groups, tend to undergo intramolecular aggregation in water but at the water-oil interface less compact conformation is preferred with PVN grafts anchoring in the oil phase and the charged PAMPS main chains residing in the aqueous phase, thus stabilizing the nanoemulsion droplets. Formation of such nanocapsules was confirmed by dynamic light scattering measurements as well as SEM and cryo-TEM imaging. Grafting density and content of the chromophores in the graft copolymers were varied in order to achieve high stability of the coated nanodroplets. It was shown that the capsules are better stabilized by the copolymers with many short hydrophobic grafts than with fewer but longer ones. Use of photoactive polyelectrolytes enabled spectroscopic investigation of the relationship between conformation of the macromolecules and stabilization of the oil-core nanocapsules. Long-term stability of the nanocapsules was achieved and further increased by multilayer shell formation using polyelectrolytes deposited via the layer-by-layer approach. The obtained capsules served as efficient nanocontainers for a hydrophobic fluorescent probe. The proposed strategy of nanocapsule preparation may be easily extended to biologically relevant polymers and applied to fabricate liquid core nanodelivery systems without the need of using low molecular weight additives which may have adverse effects in numerous biomedical applications.A surfactant-free method of preparation of nanocapsules templated on liquid cores using amphiphilic graft polyelectrolytes was developed

  15. Cytotoxic activity of paclitaxel incorporated into polyelectrolyte nanocapsules

    NASA Astrophysics Data System (ADS)

    Karabasz, Alicja; Bzowska, Monika; Łukasiewicz, Sylwia; Bereta, Joanna; Szczepanowicz, Krzysztof

    2014-04-01

    Nanoencapsulation is a promising solution for the delivery of chemotherapeutics to tumors. A method of preparation of drug-loaded nanocapsules based on the liquid core encapsulation by a sequential adsorption of a polyelectrolyte is described. An easily evaporative solvent, chloroform, was used as an oil phase. An interfacial complex formed with an oil-soluble, Food and Drug Administration-approved surfactant, and polycation poly- l-lysine (PLL) was used as a microemulsion stabilizer. A polyelectrolyte multilayer shell was constructed by a sequential adsorption of polyelectrolytes using biocompatible polyelectrolytes (PLL as a polycation and poly- l-glutamic acid as a polyanion). A hydrophobic anticancer agent, paclitaxel, was successfully encapsulated in the nanocarriers with the average size of 100 nm. In vitro analysis of the effects of nanoformulations was performed using a mouse colon carcinoma cell line CT26-CEA. Biocompatibility of the nanocapsules was evaluated using various biochemical assays. The results indicate that the cell viability was diminished by positively but not by negatively charged nanocarriers. Analysis of the cellular uptake of nanocapsules determined by flow cytometry and confocal microscopy confirmed their accumulation inside the cells. Encapsulated paclitaxel retains its cytotoxic/cytostatic activity; although its effects were weaker than those of the corresponding concentrations of the free drug. The generated nanocapsules seem to be a valuable vehicle for tumor drug delivery; although further work is needed to increase their overall activity.

  16. A new process for drug loaded nanocapsules preparation using a membrane contactor.

    PubMed

    Charcosset, Catherine; Fessi, Hatem

    2005-12-01

    In this paper, we describe a new process for the preparation of drug loaded nanocapsules using a membrane contactor which may be scaled up for industrial applications. Nanocapsules are prepared according to the nanoprecipitation method. The organic phase (solvent, polymer, oil, and drug) is pressed through the pores of an ultrafiltration membrane via the filtrate side. The aqueous phase (water and surfactant) circulates inside the membrane module, and sweeps away the nanocaspules forming at the pore outlets. Two model drugs are selected for the preparation of drug loaded nanocapsules: indomethacin and vitamin E. It is shown that indomethacin loaded nanocapsules with a mean diameter of 240 nm and vitamin E loaded nanocapsules with a mean diameter of 230 nm are obtained with a 150,000 daltons ultrafiltration membrane, a transmembrane pressure of 3 bar, and a crossflow rate of 1.7 m.s(- 1). High fluxes are also obtained (around 0.6 m3/h.m2), leading to the preparation of 1.8 10(- 3) m3 drug loaded nanocapsules in 8 min. The advantage of this membrane contactor compared to other processes for drug loaded nanocapsules preparation is shown to be its scale-up ability.

  17. The effect of monomers on the formulation of polymeric nanocapsules based on polyureas and polyamides.

    PubMed

    Montasser, I; Briançon, S; Fessi, H

    2007-04-20

    Formulation of nanocapsules based on polyureas and polyamides have been tested using a patented process. This method based on polycondensation reaction of two complementary monomers and spontaneous formation of oil in water emulsion, is an alternative concept to the known technique based on the same type of reaction used for the formulation of microcapsules, and in which the lipophilic monomer was emulsified in the organic phase before the formation of the polymeric membrane. Nanocapsules can be prepared from different monomers. Wall based on cross-linked polymer contributes to the stability of nanocapsules during and after formulation. The permeability of the polymeric wall is related to its crystallinity and contributes to the growth of nanocapsule membrane by the diffusion of the hydrophilic monomers to get stable colloidal suspensions.

  18. Ecotoxicology of Glycerol Monolaurate nanocapsules.

    PubMed

    Lopes, Leonardo Q S; Santos, Cayane G; de Almeida Vaucher, Rodrigo; Raffin, Renata P; da Silva, Aleksandro S; Baretta, Dilmar; Maccari, Ana Paula; Giombelli, Laura Caroline D D; Volpato, Andreia; Arruda, Jessyka; de Ávila Scheeren, Cecília; Baldisserotto, Bernardo; Santos, Roberto C V

    2017-05-01

    Glycerol Monolaurate (GML) is a compound with known antimicrobial potential, however it is not much used due to its low solubility in water and high melting point. The nanoencapsulation of some drugs offers several advantages such as improved stability and solubility in water. The present study aimed to produce, characterize, and evaluate the ecotoxicity of GML nanocapsules. The nanocapsules were produced and presented a mean diameter of 210nm, polydispersity index of 0.044, and zeta potential of -23.4mV. The electron microscopy images showed the nanometric size and spherical shape. The assay in soil showed that GML has a high toxicity while the GML nanocapsules showed decreased toxic effects. Nanostructuration also protected the Rhamdia quelen against the toxic effects of GML. Concluding, the formulation shows positive results and is useful to predict the success of development besides not damaging the soil.

  19. Labeling the oily core of nanocapsules and lipid-core nanocapsules with a triglyceride conjugated to a fluorescent dye as a strategy to particle tracking in biological studies

    NASA Astrophysics Data System (ADS)

    Fiel, Luana Almeida; Contri, Renata Vidor; Bica, Juliane Freitas; Figueiró, Fabrício; Battastini, Ana Maria Oliveira; Guterres, Sílvia Stanisçuaski; Pohlmann, Adriana Raffin

    2014-05-01

    The synthesis of novel fluorescent materials represents a very important step to obtain labeled nanoformulations in order to evaluate their biological behavior. The strategy of conjugating a fluorescent dye with triacylglycerol allows that either particles differing regarding supramolecular structure, i.e., nanoemulsions, nanocapsules, lipid-core nanocapsules, or surface charge, i.e., cationic nanocapsules and anionic nanocapsules, can be tracked using the same labeled material. In this way, a rhodamine B-conjugated triglyceride was obtained to prepare fluorescent polymeric nanocapsules. Different formulations were obtained, nanocapsules (NC) or lipid-core nanocapsules (LNC), using the labeled oil and Eudragit RS100, Eudragit S100, or poly(caprolactone) (PCL), respectively. The rhodamine B was coupled with the ricinolein by activating the carboxylic function using a carbodiimide derivative. Thin layer chromatography, proton nuclear magnetic resonance (1H-NMR), Fourier transform infrared spectroscopy (FTIR), UV-vis, and fluorescence spectroscopy were used to identify the new product. Fluorescent nanocapsule aqueous suspensions were prepared by the solvent displacement method. Their pH values were 4.6 (NC-RS100), 3.5 (NC-S100), and 5.0 (LNC-PCL). The volume-weighted mean diameter ( D 4.3) and polydispersity values were 150 nm and 1.05 (NC-RS100), 350 nm and 2.28 (NC-S100), and 270 nm and 1.67 (LNC-PCL). The mean diameters determined by photon correlation spectroscopy (PCS) ( z-average) were around 200 nm. The zeta potential values were +5.85 mV (NC-RS100), -21.12 mV (NC-S100), and -19.25 mV (LNC-PCL). The wavelengths of maximum fluorescence emission were 567 nm (NC-RS100 and LNC-PCL) and 574 nm (NC-S100). Fluorescence microscopy was used to evaluate the cell uptake (human macrophage cell line) of the fluorescent nanocapsules in order to show the applicability of the approach. When the cells were treated with the fluorescent nanocapsules, red emission was detected

  20. Labeling the oily core of nanocapsules and lipid-core nanocapsules with a triglyceride conjugated to a fluorescent dye as a strategy to particle tracking in biological studies

    PubMed Central

    2014-01-01

    The synthesis of novel fluorescent materials represents a very important step to obtain labeled nanoformulations in order to evaluate their biological behavior. The strategy of conjugating a fluorescent dye with triacylglycerol allows that either particles differing regarding supramolecular structure, i.e., nanoemulsions, nanocapsules, lipid-core nanocapsules, or surface charge, i.e., cationic nanocapsules and anionic nanocapsules, can be tracked using the same labeled material. In this way, a rhodamine B-conjugated triglyceride was obtained to prepare fluorescent polymeric nanocapsules. Different formulations were obtained, nanocapsules (NC) or lipid-core nanocapsules (LNC), using the labeled oil and Eudragit RS100, Eudragit S100, or poly(caprolactone) (PCL), respectively. The rhodamine B was coupled with the ricinolein by activating the carboxylic function using a carbodiimide derivative. Thin layer chromatography, proton nuclear magnetic resonance (1H-NMR), Fourier transform infrared spectroscopy (FTIR), UV-vis, and fluorescence spectroscopy were used to identify the new product. Fluorescent nanocapsule aqueous suspensions were prepared by the solvent displacement method. Their pH values were 4.6 (NC-RS100), 3.5 (NC-S100), and 5.0 (LNC-PCL). The volume-weighted mean diameter (D4.3) and polydispersity values were 150 nm and 1.05 (NC-RS100), 350 nm and 2.28 (NC-S100), and 270 nm and 1.67 (LNC-PCL). The mean diameters determined by photon correlation spectroscopy (PCS) (z-average) were around 200 nm. The zeta potential values were +5.85 mV (NC-RS100), -21.12 mV (NC-S100), and -19.25 mV (LNC-PCL). The wavelengths of maximum fluorescence emission were 567 nm (NC-RS100 and LNC-PCL) and 574 nm (NC-S100). Fluorescence microscopy was used to evaluate the cell uptake (human macrophage cell line) of the fluorescent nanocapsules in order to show the applicability of the approach. When the cells were treated with the fluorescent nanocapsules, red emission was

  1. Labeling the oily core of nanocapsules and lipid-core nanocapsules with a triglyceride conjugated to a fluorescent dye as a strategy to particle tracking in biological studies.

    PubMed

    Fiel, Luana Almeida; Contri, Renata Vidor; Bica, Juliane Freitas; Figueiró, Fabrício; Battastini, Ana Maria Oliveira; Guterres, Sílvia Stanisçuaski; Pohlmann, Adriana Raffin

    2014-01-01

    The synthesis of novel fluorescent materials represents a very important step to obtain labeled nanoformulations in order to evaluate their biological behavior. The strategy of conjugating a fluorescent dye with triacylglycerol allows that either particles differing regarding supramolecular structure, i.e., nanoemulsions, nanocapsules, lipid-core nanocapsules, or surface charge, i.e., cationic nanocapsules and anionic nanocapsules, can be tracked using the same labeled material. In this way, a rhodamine B-conjugated triglyceride was obtained to prepare fluorescent polymeric nanocapsules. Different formulations were obtained, nanocapsules (NC) or lipid-core nanocapsules (LNC), using the labeled oil and Eudragit RS100, Eudragit S100, or poly(caprolactone) (PCL), respectively. The rhodamine B was coupled with the ricinolein by activating the carboxylic function using a carbodiimide derivative. Thin layer chromatography, proton nuclear magnetic resonance ((1)H-NMR), Fourier transform infrared spectroscopy (FTIR), UV-vis, and fluorescence spectroscopy were used to identify the new product. Fluorescent nanocapsule aqueous suspensions were prepared by the solvent displacement method. Their pH values were 4.6 (NC-RS100), 3.5 (NC-S100), and 5.0 (LNC-PCL). The volume-weighted mean diameter (D 4.3) and polydispersity values were 150 nm and 1.05 (NC-RS100), 350 nm and 2.28 (NC-S100), and 270 nm and 1.67 (LNC-PCL). The mean diameters determined by photon correlation spectroscopy (PCS) (z-average) were around 200 nm. The zeta potential values were +5.85 mV (NC-RS100), -21.12 mV (NC-S100), and -19.25 mV (LNC-PCL). The wavelengths of maximum fluorescence emission were 567 nm (NC-RS100 and LNC-PCL) and 574 nm (NC-S100). Fluorescence microscopy was used to evaluate the cell uptake (human macrophage cell line) of the fluorescent nanocapsules in order to show the applicability of the approach. When the cells were treated with the fluorescent nanocapsules, red emission was

  2. Nanoparticles: A very versatile nanocapsule

    NASA Astrophysics Data System (ADS)

    Kuykendall, Darrell W.; Zimmerman, Steven C.

    2007-04-01

    Numerous copies of a pumpkin-shaped molecule can be linked together to form a nanocapsule shell that can trap compounds inside. The outer surface of this capsule can be decorated with other species by plugging them into the cavities of the hollowed-out pumpkins.

  3. Tribological Properties of Carbon Nanocapsule Particles as Lubricant Additive.

    PubMed

    Jeng, Yeau-Ren; Huang, Yao-Huei; Tsai, Ping-Chi; Hwang, Gan-Lin

    2014-10-01

    An experimental investigation is performed into the tribological properties of mineral oil lubricants containing carbon nanocapsules (CNCs) additives with various concentrations (wt.%). Friction characteristics and wear behaviors at contact interfaces are examined by the block-on-ring tests, high-resolution transmission electron microscopy (HRTEM), and mapping (MAP) analysis. The results suggest that the addition of CNCs to the mineral oil yields an effective reduction in the friction coefficient at the contact interface. Molecular dynamics (MD) simulations clarify the lubrication mechanism of CNCs at the sliding system, indicating the tribological properties are essentially sensitive to the structural evolutions of CNCs.

  4. Biodegradable double nanocapsule as a novel multifunctional carrier for drug delivery and cell imaging

    PubMed Central

    Qian, Kun; Wu, Jing; Zhang, Enqi; Zhang, Yingge; Fu, Ailing

    2015-01-01

    Highly-efficient delivery of macromolecules into cells for both imaging and therapy (theranostics) remains a challenge for the design of a delivery system. Here, we suggested a novel hybrid protein–lipid polymer nanocapsule as an effective and nontoxic drug delivery and imaging carrier. The biodegradable nanocapsules showed the typical double emulsion features, including fluorescently labeled bovine serum albumin shell, oil phase containing poly(lactic-co-glycolic acid) and linoleic acid, and inner aqueous phase. The nanocapsules were spherical in shape, with an average size of about 180 nm. Proteins packed into the inner aqueous phase of the nanocapsules could be delivered into cells with high efficiency, and the fluorescence of the fluorescently labeled bovine serum albumin could be used for tracing the protein migration and cellular location. Further studies suggested that the co-delivery of transcription factor p53 and lipophilic drug paclitaxel with the nanocapsules acted synergistically to induce Hela cell apoptosis, and the fluorescence of apoptotic cells was clearly observed under a fluorescence microscope. Such multifunctional delivery system would have great potential applications in drug delivery and theranostic fields. PMID:26203242

  5. Multifunctional Bi2S3/PLGA nanocapsule for combined HIFU/radiation therapy.

    PubMed

    Yao, Ming-hua; Ma, Ming; Chen, Yu; Jia, Xiao-qing; Xu, Guang; Xu, Hui-xiong; Chen, Hang-rong; Wu, Rong

    2014-09-01

    A multifunctional organic-inorganic hybrid nanocapsule based on Bi2S3-embedded poly (lactic-co-glycolic acid) (PLGA) nanocapsule has been elaborately designed to combine the merits of both polymeric shell structure and Bi2S3 nanoparticles. Hydrophobic Bi2S3 nanoparticles were successfully introduced into the PLGA nanocapsules via a facile and efficient water/oil/water (W/O/W) emulsion strategy. The elastic polymeric PLGA shell provides the excellent capability of ultrasound contrast imaging to the Bi2S3/PLGA. Meanwhile, the potential of these microcapsules to enhance the high intensity focused ultrasound (HIFU) therapy was demonstrated. Importantly, this research provided the first example of both in vitro and in vivo to demonstrate the radiosensitization effect of Bi2S3-embedded PLGA hybrid nanocapsules against prostate cancer under external X-ray irradiation. Thus, the successful integration of the Bi2S3 and PLGA nanocapsules provided an alternative strategy for the highly efficient ultrasound guided HIFU/RT synergistic therapy.

  6. Fabrication of polymeric nanocapsules from curcumin-loaded nanoemulsion templates by self-assembly.

    PubMed

    Abbas, Shabbar; Karangwa, Eric; Bashari, Mohanad; Hayat, Khizar; Hong, Xiao; Sharif, Hafiz Rizwan; Zhang, Xiaoming

    2015-03-01

    In this study, biodegradable polymeric nanocapsules were prepared by sequential deposition of food-grade polyelectrolytes through the self-assembling process onto the oil (medium chain triglycerides) droplets enriched with curcumin (lipophilic bioactive compound). Optimum conditions were used to prepare ultrasound-assisted nanoemulsions stabilized by octenyl-succinic-anhydride (OSA)-modified starch. Negatively charged droplets (-39.4 ± 1.84 mV) of these nanoemulsions, having a diameter of 142.7 ± 0.85 nm were used as templates for the fabrication of nanocapsules. Concentrations of layer-forming cationic (chitosan) and anionic (carboxymethylcellulose) biopolymers were optimized based on the mean droplet/particle diameter (MDD/MPD), polydispersity index (PDI) and net charge on the droplets/capsules. Prepared core-shell structures or nanocapsules, having MPD of 159.85 ± 0.92 nm, were characterized by laser diffraction (DLS), ζ-potential (ZP), atomic force microscopy (AFM), transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM). Furthermore, physical stability of curcumin-loaded nanocapsules in suspension was determined and compared at different storage temperatures. This study may provide information regarding the formation of ultrasound-assisted polymeric nanocapsules from the nanoemulsion templates which could be helpful in the development of delivery systems for lipophilic food bioactives. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Characterization of Different Functionalized Lipidic Nanocapsules as Potential Drug Carriers

    PubMed Central

    Sánchez-Moreno, Paola; Ortega-Vinuesa, Juan Luis; Martín-Rodríguez, Antonio; Boulaiz, Houría; Marchal-Corrales, Juan Antonio; Peula-García, José Manuel

    2012-01-01

    Lipid nanocapsules (LNC) based on a core-shell structure consisting of an oil-filled core with a surrounding polymer layer are known to be promising vehicles for the delivery of hydrophobic drugs in the new therapeutic strategies in anti-cancer treatments. The present work has been designed as basic research about different LNC systems. We have synthesized—and physico-chemically characterized—three different LNC systems in which the core was constituted by olive oil and the shell by different phospholipids (phosphatidyl-serine or lecithin) and other biocompatible molecules such as Pluronic® F68 or chitosan. It is notable that the olive-oil-phosphatidyl-serine LCN is a novel formulation presented in this work and was designed to generate an enriched carboxylic surface. This carboxylic layer is meant to link specific antibodies, which could facilitate the specific nanocapsule uptake by cancer cells. This is why nanoparticles with phosphatidyl-serine in their shell have also been used in this work to form immuno-nanocapsules containing a polyclonal IgG against a model antigen (C-reactive protein) covalently bounded by means of a simple and reproducible carbodiimide method. An immunological study was made to verify that these IgG-LNC complexes showed the expected specific immune response. Finally, a preliminary in vitro study was performed by culturing a breast-carcinoma cell line (MCF-7) with Nile-Red-loaded LNC. We found that these cancer cells take up the fluorescent Nile- Red molecule in a process dependent on the surface properties of the nanocarriers. PMID:22408461

  8. Producing Light Oil from a Frozen Reservoir: Reservoir and Fluid Characterization of Umiat Field, National Petroleum Reserve, Alaska

    SciTech Connect

    Hanks, Catherine

    2012-12-31

    Umiat oil field is a light oil in a shallow, frozen reservoir in the Brooks Range foothills of northern Alaska with estimated oil-in-place of over 1 billion barrels. Umiat field was discovered in the 1940’s but was never considered viable because it is shallow, in the permafrost, and far from any transportation infrastructure. The advent of modern drilling and production techniques has made Umiat and similar fields in northern Alaska attractive exploration and production targets. Since 2008 UAF has been working with Renaissance Alaska Inc. and, more recently, Linc Energy, to develop a more robust reservoir model that can be combined with rock and fluid property data to simulate potential production techniques. This work will be used to by Linc Energy as they prepare to drill up to 5 horizontal wells during the 2012-2013 drilling season. This new work identified three potential reservoir horizons within the Cretaceous Nanushuk Formation: the Upper and Lower Grandstand sands, and the overlying Ninuluk sand, with the Lower Grandstand considered the primary target. Seals are provided by thick interlayered shales. Reserve estimates for the Lower Grandstand alone range from 739 million barrels to 2437 million barrels, with an average of 1527 million bbls. Reservoir simulations predict that cold gas injection from a wagon-wheel pattern of multilateral injectors and producers located on 5 drill sites on the crest of the structure will yield 12-15% recovery, with actual recovery depending upon the injection pressure used, the actual Kv/Kh encountered, and other geologic factors. Key to understanding the flow behavior of the Umiat reservoir is determining the permeability structure of the sands. Sandstones of the Cretaceous Nanushuk Formation consist of mixed shoreface and deltaic sandstones and mudstones. A core-based study of the sedimentary facies of these sands combined with outcrop observations identified six distinct facies associations with distinctive permeability

  9. Frozen Frozen CO2

    NASA Technical Reports Server (NTRS)

    2005-01-01

    2 October 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of frozen carbon dioxide in the south polar residual cap of Mars. Much of the south polar residual cap exhibits terrain that resembles stacks of sliced Swiss cheese, but this portion of the cap lacks the typical, circular depressions that characterize much of the region. Carbon dioxide on Mars freezes at a temperature of around 148 Kelvins, which is -125oC or about -193oF.

    Location near: 87.2oS, 28.4oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  10. Graphitic nanocapsules: design, synthesis and bioanalytical applications.

    PubMed

    Ding, Ding; Xu, Yiting; Zou, Yuxiu; Chen, Long; Chen, Zhuo; Tan, Weihong

    2017-08-03

    Graphitic nanocapsules are emerging nanomaterials which are gaining popularity along with the development of carbon nanomaterials. Their unique physical and chemical properties, as well as good biocompatibility, make them desirable agents for biomedical and bioanalytical applications. Through rational design, integrating graphitic nanocapsules with other materials provides them with additional properties which make them versatile nanoplatforms for bioanalysis. In this feature article, we present the use and performance of graphitic nanocapsules in a variety of bioanalytical applications. Based on their chemical properties, the specific merits and limitations of magnetic, hollow, and noble metal encapsulated graphitic nanocapsules are discussed. Detection, multi-modal imaging, and therapeutic applications are included. Future directions and potential solutions for further biomedical applications are also suggested.

  11. Photo-oxidative action in MCF-7 cancer cells induced by hydrophobic cyanines loaded in biodegradable microemulsion-templated nanocapsules.

    PubMed

    Wilk, Kazimiera A; Zielińska, Katarzyna; Pietkiewicz, Jadwiga; Skołucka, Nina; Choromańska, Anna; Rossowska, Joanna; Garbiec, Arnold; Saczko, Jolanta

    2012-07-01

    Searching for photodynamic therapy-effective nanocarriers which enable a photosensitizer to be selectively delivered to tumor cells with enhanced bioavailability and diminished dark cytotoxicity is of current interest. We have employed a polymer-based nanoparticle approach to encapsulate the cyanine-type photosensitizer IR-780 in poly(n-butyl cyanoacrylate) (PBCA) nanocapsules. The latter were fabricated by interfacial polymerization in oil-in-water (o/w) microemulsions formed by dicephalic and gemini saccharide-derived surfactants. Nanocarriers were characterized by SEM, AFM and DLS. The efficiency of PBCA nanocapsules as a potential system of photosensitizer delivery to human breast cancer cells was established by dark and photocytotoxicity as the function of the cellular mitochondria. The photodynamic effect of cyanine IR-780 was determined by investigation of oxidative stress markers. The nanocapsules were the main focus of our studies to examine their cellular uptake and dark and photocytotoxicity as the function of the cellular mitochondria as well as oxidative stress markers (i.e., lipid peroxidation and protein damage) in MCF-7/WT cancer cells. The effects of encapsulated IR-780 were compared with those of native photosensitizer. The penetration of the nanocapsules into cancer cells was visualized by CLSM and their uptake was estimated by FACS analysis. Cyanine IR-780 delivered in PBCA nanocapsules to MCF-7/WT cells retains its sensitivity upon photoirradiation and it is regularly distributed in the cell cytoplasm. The intensity of the photosensitizer-generated oxidative stress depends on IR-780 release from the effective uptake of polymeric nanocapsules and seems to remain dependent upon the surfactant structure in o/w microemulsion-based templates applied to nanocapsule fabrication.

  12. Nanofibrous photocatalysts from electrospun nanocapsules.

    PubMed

    Jiang, Shuai; Lieberwirth, Ingo; Landfester, Katharina; Muñoz-Espí, Rafael; Crespy, Daniel

    2017-10-06

    We present the design of multicompartment metal oxide/silica nanofibrous photocatalysts by colloid-electrospinning and subsequent calcination. During the calcination process, silica nanomaterials are cemented to form the fibrous framework and metal oxide precursors are crystallized inside and onto the fibers. This multicompartment nanofibrous structure, constructed with nanoparticles and core-shell nanocapsules, is therefore beneficial for the separation of the materials and the light utilization due to the multiple reflections and scattering of incident light in the cavities. The photocatalytic activity of the fibers was verified by the successful degradation of a model dye rhodamine B. This synthetic methodology is a universal approach for the fabrication of nanomaterials with hierarchical hollow structures, which are emerging in energy and environmental related applications.

  13. Nanofibrous photocatalysts from electrospun nanocapsules

    NASA Astrophysics Data System (ADS)

    Jiang, Shuai; Lieberwirth, Ingo; Landfester, Katharina; Muñoz-Espí, Rafael; Crespy, Daniel

    2017-10-01

    We present the design of multicompartment metal oxide/silica nanofibrous photocatalysts by colloid-electrospinning and subsequent calcination. During the calcination process, silica nanomaterials are cemented to form the fibrous framework and metal oxide precursors are crystallized inside and onto the fibers. This multicompartment nanofibrous structure, constructed with nanoparticles and core–shell nanocapsules, is therefore beneficial for the separation of the materials and the light utilization due to the multiple reflections and scattering of incident light in the cavities. The photocatalytic activity of the fibers was verified by the successful degradation of a model dye rhodamine B. This synthetic methodology is a universal approach for the fabrication of nanomaterials with hierarchical hollow structures, which are emerging in energy and environmental related applications.

  14. Balancing the effect of corona on therapeutic efficacy and macrophage uptake of lipid nanocapsules.

    PubMed

    Sánchez-Moreno, P; Buzón, P; Boulaiz, H; Peula-García, J M; Ortega-Vinuesa, J L; Luque, I; Salvati, A; Marchal, J A

    2015-08-01

    Several studies have shown the potential of biocompatible lipid nanocapsules as hydrophobic drug delivery systems. Understanding the factors that determine the interactions of these oil-in-water nanoemulsions with cells is a necessary step to guide the design of the most effective formulations. The aim of this study was to probe the ability of two surfactants with a markedly different nature, a non-ionic poloxamer, and a charged phospholipid, to prepare formulations with shells of different composition and different surface properties. Thus we determined their effects on the interaction with biological environments. In particular, we investigated how the shell formulation affected the adsorption of biomolecules from the surrounding biological fluids on the nanocapsule surface (corona formation). A complete physicochemical characterization including an isothermal titration calorimetry (ITC) study revealed that the use of poloxamer led to nanocapsules with a marked reduction in the number of protein-binding sites. Surface hydrophilicity and changes in corona formation strongly correlated to changes in uptake by cancer cells and by macrophages. Our results indicate that the nature and concentration of surfactants in the nanocapsules can be easily manipulated to effectively modulate their surface architecture with the aim of controlling the environmental interactions, thus optimizing functionality for in vivo applications. In particular, addition of surfactants that reduce protein binding can modulate nanoparticle clearance by the immune system, but also screens the desired interactions with cells, leading to lower uptake, thus lower therapeutic efficacy. The two effects need to be balanced in order to obtain successful formulations.

  15. Biodegradable poly(L-lactic acid)-lavender nanocapsules: synthesis, controlled release, and application in remedy of sleep disorder.

    PubMed

    Daoud, Walid A; Ngan, Mandy; Cheuk, Kevin

    2010-02-01

    In this study, nanocapsules of poly(L-lactic acid) (PLLA) containing lavender oil were synthesized by solvent evaporation emulsion. Poly(L-lactic acid) is a biodegradable aliphatic polyester derived from lactic acid formed by bacterial fermentation of glucose-rich substances. Lavender oil is a plant extract that finds uses in phytotherapy. It is reputed as anti-septic, anti-depressant and sleep promoter. Encapsulation is a technique used to encase tiny oil droplets with a thin and permeable coating that allows for a controlled release of the volatile oil. The size and morphology of the nanocapsules were characterized by scanning electron microscope. The particle size and distribution were measured by photon correlation spectroscopy. The time-controlled release of the lavender oil was studied and the use of the lavender capsules in the remedy of sleep disorder was investigated.

  16. Effect of different concentrations of soybean lecithin and virgin coconut oil in Tris-based extender on the quality of chilled and frozen-thawed bull semen

    PubMed Central

    Tarig, A. A.; Wahid, H.; Rosnina, Y.; Yimer, N.; Goh, Y. M.; Baiee, F. H.; Khumran, A. M.; Salman, H.; Assi, M. A.; Ebrahimi, M.

    2017-01-01

    Aim: The objective of this study was to evaluate the effects of different concentrations of soybean lecithin (SL) and virgin coconut oil (VCO) in Tris-based extender on chilled and frozen-thawed bull semen quality parameters. Materials and Methods: A total of 24 ejaculates were collected from four bulls via an electroejaculator. Semen samples were diluted with 2% VCO in Tris-based extender which consists of various concentrations of SL (1, 1.25, 1.5, and 1.75%). A 20% egg yolk in Tris used as a positive control (C+). The diluted semen samples were divided into two fractions; one for chilling which were stored at 4°C for 24, 72, and 144 h before evaluated for semen quality parameters. The second fraction used for freezing was chilled for 3 h at 4°C, packed into 0.25 mL straws and then cryopreserved in liquid nitrogen. The samples were then evaluated after 7 and 14 days. Chilled and frozen semen samples were thawed at 37°C and assessed for general motility using computer-assisted semen analysis, viability, acrosome integrity and morphology (eosin-nigrosin stain), membrane integrity, and lipid peroxidation using thiobarbituric acid reaction test. Results: The results showed that all the quality parameters assessed were significantly (p<0.05) improved at 1.5% SL concentration in chilled semen. Treatment groups of 1, 1.25, 1.5, and 1.75% SL were higher in quality parameters than the control group (C+) in chilled semen. However, all the quality parameters in frozen-thawed semen were significantly higher in the C+ than the treated groups. Conclusion: In conclusion, supplementation of 1.5% SL in 2% VCO Tris-based extender enhanced the chilled bull semen. However, there was no marked improvement in the frozen-thawed quality parameters after treatment. PMID:28717321

  17. Frozen shoulder.

    PubMed

    Wadsworth, C T

    1986-12-01

    Widespread use of the label "frozen shoulder" as a diagnosis for any stiff and painful shoulder condition has led to its becoming a rather meaningless, catchall term. In addition to confounding both the lay public and health care professionals, this indiscriminate labeling may prevent a patient from receiving appropriate treatment. In this article, I define frozen shoulder and review its pathologic and etiologic factors, epidemiology, natural history, and diagnosis. I present this information in correlation with an examination process to assist physical therapists in identifying suspected cases of frozen shoulder. I also present the current options for treatment, including physical therapy management with physical agents and exercise.

  18. Study on the preparation of Pt nanocapsules

    NASA Astrophysics Data System (ADS)

    Zhang, Yi-fan; Ji, Zhen; Chen, Ke; Liu, Bo-wen; Jia, Cheng-chang; Yang, Shan-wu

    2017-01-01

    Ag@Pt core-shell nanoparticles (Ag@Pt NPs) were prepared by a co-reduction method. Pt nanocapsules with diameters of less than 10 nm were obtained by an electrochemical method. Cyclic voltammetry (CV) scanning was used to cavitate the Ag@Pt NPs, and the morphology, structure, and cavitation conditions were studied. The results indicate that the effective cavitation conditions to obtain Pt nanoparticles from Ag@Pt NPs are a scanning voltage of 0 to 0.8 V and continuous CV scanning over 2 h. This cavitation method is also applicable for the syntheses of Ir, Ru, and Ru-Pt nanocapsules.

  19. Microwave absorption properties of Ni/(C, silicides) nanocapsules

    PubMed Central

    2012-01-01

    The microwave absorption properties of Ni/(C, silicides) nanocapsules prepared by an arc discharge method have been studied. The composition and the microstructure of the Ni/(C, silicides) nanocapsules were determined by means of X-ray diffraction, X-ray photoelectric spectroscopy, and transmission electron microscope observations. Silicides, in the forms of SiOx and SiC, mainly exist in the shells of the nanocapsules and result in a large amount of defects at the ‘core/shell’ interfaces as well as in the shells. The complex permittivity and microwave absorption properties of the Ni/(C, silicides) nanocapsules are improved by the doped silicides. Compared with those of Ni/C nanocapsules, the positions of maximum absorption peaks of the Ni/(C, silicides) nanocapsules exhibit large red shifts. An electric dipole model is proposed to explain this red shift phenomenon. PMID:22548846

  20. High-pressure Raman spectroscopy of carbon onions and nanocapsules

    NASA Astrophysics Data System (ADS)

    Guo, J. J.; Liu, G. H.; Wang, X. M.; Fujita, T.; Xu, B. S.; Chen, M. W.

    2009-08-01

    We report high-pressure Raman spectra of carbon onions and nanocapsules investigated by diamond anvil cell experiments. The pressure coefficient and elastic behavior of carbon onions and nanocapsules are found to be very similar to those of multiwall carbon nanotubes. Additionally, detectable structure changes, particularly the collapse of the concentric graphite structure, cannot been seen at pressures as high as ˜20 GPa, demonstrating that carbon onions and nanocapsules have significant hardness and can sustain very high pressures.

  1. Polyarginine nanocapsules: a new platform for intracellular drug delivery

    NASA Astrophysics Data System (ADS)

    Lozano, M. V.; Lollo, G.; Alonso-Nocelo, M.; Brea, J.; Vidal, A.; Torres, D.; Alonso, M. J.

    2013-03-01

    This report describes the development of a new nanocarrier, named as polyarginine (PArg) nanocapsules, specifically designed for overcoming cellular barriers. These nanocapsules are composed of an oily core and a PArg corona. The attachment of the PArg corona was mediated by its interaction with the oily core, which was conveniently stabilized with phosphatidylcholine. Hybrid PArg/PEG nanocapsules could also be obtained by introducing PEG-stearate in the nanocapsules formation process. The nanocapsules had an average size in the range of 120-160 nm, and a positive surface charge, which varied between +56 and +28 mV for PArg and PArg/PEG nanocapsules, respectively. They could accommodate significant amounts of lipophilic drugs, i.e., docetaxel, in their core, and also polar negatively charged molecules, i.e., plasmid DNA, on their coating. As a preliminary proof-of-principle, we explored the ability of these nanocarriers to enter cancer cells and to inhibit proliferation in the non-small cell lung cancer NCI-H460 cell line, using flow cytometry and confocal microscopy analysis. The results indicated that PArg nanocapsules are rapidly and massively accumulated into the NCI-H460 cells and that the PArg shell plays a critical role in the internalization process. Moreover, the incubation with docetaxel-loaded nanocapsules with NCI-H460 cells led to an enhanced inhibition of their proliferation, as compared to the free drug. Overall, this is the first report of the potential of PArg nanocapsules as intracellular drug delivery vehicles.

  2. Introducing defects into metal-seamed nanocapsules using mixed macrocycles.

    PubMed

    Fowler, Drew A; Rathnayake, Asanka S; Kennedy, Stuart; Kumari, Harshita; Beavers, Christine M; Teat, Simon J; Atwood, Jerry L

    2013-08-21

    The synthesis and single-crystal X-ray diffraction structure of a dimeric zinc-seamed nanocapsule using a mixed pyrogallol/resorcinol[4]arene are presented. The use of "mixed" macrocycles results in an incomplete seam of coordination bonds around the nanocapsule's typically octa-metalated belt. The self-assembly of the nanocapsule occurs such that the single resorcinol moiety of each macrocycle aligns transversely. This yields a hepta-metalated capsule where the defect occurs in such a way as to provide minimal disruption to the overall structure of the nanocapsule.

  3. Frozen shoulder.

    PubMed Central

    Anton, H. A.

    1993-01-01

    The frozen shoulder is a common cause of shoulder pain and disability. Most patients slowly improve over 12 to 24 months. Some have prolonged loss of movement, pain, and associated disability. Treatments include physiotherapy, corticosteroid injections, and manipulation. Clinical trials of these treatments have produced conflicting results. PMID:8374364

  4. Improved photostability and cytotoxic effect of coenzyme Q10 by its association with vitamin E acetate in polymeric nanocapsules.

    PubMed

    Pegoraro, Natháli S; Mattiazzi, Juliane; da Silveira, Elita F; Azambuja, Juliana H; Braganhol, Elizandra; Cruz, Letícia

    2017-06-07

    The present study showed the development of nanocapsules containing the association of the coenzyme Q10 and vitamin E acetate and the evaluation of their effect on in vitro cells culture of malignant glioma and melanoma. In order to investigate if nanocapsules are able to protect coenzyme Q10 from degradation under UVC radiation, a photostability study was carried out. For this, three concentrations of vitamin E acetate were evaluated (1%, 2%, or 3%). Nanocapsules presented suitable physicochemical characteristics and were able to protect coenzyme Q10 from photodegradation. In addition, this protection was influenced by higher vitamin E acetate concentrations, attributing to this oil an important role on coenzyme Q10 photostabilization. Regarding to in vitro citotoxicity assay, nanocapsules containing coenzyme Q10 and 2% vitamin E significantly reduced glioma and melanoma cell viability in 61% and 66%, respectively. In this sense, these formulations represent interesting platforms for the delivery of coenzyme Q10 and vitamin E acetate, presenting effect on the reduction of malignant cells viability.

  5. Physicochemical properties of natural phenolics from grapes and olive oil byproducts and their antioxidant activity in frozen horse mackerel fillets.

    PubMed

    Pazos, Manuel; Alonso, Ana; Fernández-Bolaños, Juan; Torres, Josep L; Medina, Isabel

    2006-01-25

    The reducing and chelating capacities and the affinity for the incorporation into the fish muscle of grape procyanidins, hydroxytyrosol, and propyl gallate were studied together with their antioxidant activity in frozen horse mackerel (Trauchurus trauchurus) fillets. Fillets were supplemented with phenolic antioxidants by (a) spraying an aqueous phenolic solution, (b) glazing with an aqueous phenolic solution, and (c) a previous washing of fillets with water plus spraying an aqueous phenolic solution. The effect of washing on the endogenous pro-oxidant/antioxidant balance of the fillets was also determined. All phenolic compounds were effective delaying lipid oxidation in the fish fillets. The order of antioxidant efficiency in spraying and glazing was propyl gallate > hydroxytyrosol > procyanidins, which was similar to the reducing power of these phenolics, but did not show any correlation with their chelating capacity and their affinity to the fish muscle. Washing the fillets with water prior to spraying phenols increased synergistically the antioxidant activity of grape procyanidins and changed the relative antioxidant efficiency to propyl gallate approximately procyanidins > hydroxytyrosol. This synergism may be a result of a better distribution of the procyanidins onto the fillet surface because of the residual water that remained on the fillets surface after washing.

  6. Poly-L-asparagine nanocapsules as anticancer drug delivery vehicles.

    PubMed

    Rivera-Rodríguez, G R; Alonso, M J; Torres, D

    2013-11-01

    This work presents for the first time the development of novel poly-L-asparagine (PASN) nanocapsules and the in vitro evaluation of their potential as anticancer drug delivery systems. The design of PASN nanocapsules was inspired by the well-known avidity of cancer cells for the amino acid L-asparagine together with the expected ability of this hydrophilic polymer to escape to the mononuclear phagocytic system. Besides, these nanocapsules have an oily reservoir, which enables the efficient encapsulation of lipophilic drugs. PASN nanocapsules were obtained by an emulsification-polymer layer deposition process, which involves using a cationic surfactant as a bridge for the interaction of PASN with the lipid core. PASN nanocapsules showed sizes of around 170-200 nm and negative zeta potential values (around -20 mV to -40 mV). The model anticancer drug docetaxel was efficiently encapsulated (around 75%) and retained within the nanocapsule's structure upon dilution in a simulated physiological medium. Moreover, these nanocapsules exhibited the ability to interact with the NCI-H460 human cancer cells and to enhance the cellular toxicity of the anticancer drug. All these features together with their adequate stability profile render these nanocapsules a new attractive platform for anticancer intracellular drug delivery. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. p,p'-Methoxyl-diphenyl diselenideincorporation into polymeric nanocapsules improves its antinociceptive action: Physicochemical and behavioral studies.

    PubMed

    Sari, Marcel Henrique Marcondes; Ferreira, Luana Mota; AngonesiZborowski, Vanessa; Araujo, Paulo Cesar Oliveira; Nadal, Jessica Mendes; Farago, Paulo Vitor; Cruz, Letícia; Nogueira, Cristina Wayne

    2017-09-01

    The p,p'-methoxyl-diphenyl diselenide [(OMePhSe)2] is an, organoselenium compound that elicits antinociceptive action in different, animal models of pain. However, the compound has physicochemical, Limitations that delay its clinical studies. Herein, (OMePhSe)2, nanocapsules were developed and their physicochemical properties were, analyzed using different techniques (Scanning electron microscopy with, field emissionguns, wide-angle X-ray diffractometry, fourier-transform, infrared spectroscopy, thermogravimetric analysis and differential, scanning calorimetry). The antinociceptive action of (OMePhSe)2 free or, nanoencapsulated was evaluated in an animal model of thermal nociception., The (OMePhSe)2 nanocapsules or the free compound (25mg/kg, 10ml/kg), were administered to Swiss mice by the intragastric (i.g.), intraperitoneal (i.p.) or subcutaneous (s.c.) route in a single or, repeated administration regimen. The (OMePhSe)2 nanocapsules had, spherical shape, no chemical interaction among the formulation components, and high thermal stability. Treatment with (OMePhSe)2 elicited an, antinociceptive action independent of the administration route and, regimen schedule. The (OMePhSe)2 incorporation into nanocapsules, prolonged and improved the compound antinociceptive action. The, (OMePhSe)2 antinociceptive action was influenced by the route of, administration (intragastric>intraperitoneal>subcutaneous) and by the, vehicle used (NCs>canola oil). Altogether, the current study, demonstrated that the (OMePhSe)2 nanoencapsulation increased the compound, thermal stability and the antinociceptive action in mice, suggesting that, the polymeric nanocapsules provided advantages in comparison to the free, compound form. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Dietary α-linolenic acid from flaxseed oil or eicosapentaenoic and docosahexaenoic acids from fish oil differentially alter fatty acid composition and characteristics of fresh and frozen-thawed bull semen.

    PubMed

    Moallem, Uzi; Neta, Noam; Zeron, Yoel; Zachut, Maya; Roth, Zvi

    2015-04-15

    Incorporation rates of dietary omega-3 (n-3) fatty acids (FAs) from different sources into bull plasma and sperm and the effects on physiological characteristics of fresh and frozen-thawed semen were determined. Fifteen fertile bulls were assigned to three treatment groups and supplemented for 13 weeks with encapsulated fat: (1) SFA-360 g/d per bull saturated FA; (2) FLX-450 g/d per bull providing 84.2 g/d C18:3n-3 (α-linolenic acid) from flaxseed oil; and (3) FO-450 g/d per bull providing 8.7 g/d C20:5n-3 (eicosapentaenoic acid) and 6.5 g/d C22:6n-3 (docosahexaenoic acid, DHA) from fish oil. Blood samples were taken every 2 weeks and semen was collected weekly. With respect to the FA supplements, the proportion of α-linolenic acid in plasma increased in the FLX bulls, whereas that of DHA was increased in the FO bulls, within 2 weeks. However, changes in the sperm FA fraction were first expressed in the sixth week of supplementation: in the FO and FLX bulls the DHA proportion increased (P < 0.001), whereas that of C22:5n-6 FAs (docosapentaenoic acid [DPA] n-6) decreased (P < 0.001). Sperm motility and progressive motility in fresh semen were higher (P < 0.05), and the fading rate tended to be lower in the FLX than in FO bulls (P < 0.06). Furthermore, sperm motility, progressive motility, and velocity in frozen-thawed semen were higher in FLX than in the other groups (P < 0.008). These findings indicate that the proportion of DHA in sperm can be increased at the expense of DPAn-6 by either FO or FLX supplementation, indicating de novo elongation and desaturation of short- into longer-chain n-3 FAs in testes. Furthermore, the moderate exchange of DHA and DPAn-6 in the FLX group's sperm was associated with changes in the characteristics of both fresh and frozen-thawed semen, suggesting the importance of the ratio between these two FAs for sperm structure and function.

  9. Hollow chitosan/alginate nanocapsules for bioactive compound delivery.

    PubMed

    Rivera, Melissa C; Pinheiro, Ana C; Bourbon, Ana I; Cerqueira, Miguel A; Vicente, António A

    2015-08-01

    This work aimed at the development of biodegradable nanocapsules as carriers of two bioactive compounds, 5-aminosalycilic acid and glycomacropeptide. Nanocapsules were produced through layer-by-layer (LbL) deposition of chitosan (CH) and alginate (ALG) layers on polystyrene nanoparticles. The bioactive compounds were incorporated on the third layer of the nanocapsules being its encapsulation efficiency and release behaviour evaluated. The LbL deposition process, stability, morphology and size of the multilayer nanocapsules were monitored by means of zeta potential and transmission electron microscopy (TEM). The bioactive compounds release from the CH/ALG nanocapsules was successfully described by a mathematical model (linear superimposition model - LSM), which allowed concluding that bioactive compounds release is due to both Brownian motion and the polymer relaxation of the CH/ALG layers. Final results demonstrated that the synthesized LbL hollow nanocapsules presented spherical morphology and a good capacity to encapsulate different bioactive compounds, being the best results obtained for the system containing 5-aminosalycilic acid (with an encapsulation efficiency of approximately 70%). CH/ALG multilayer nanocapsules could be a promising carrier of bioactive compounds for applications in food and pharmaceutical industries.

  10. Nanoencapsulation of Rose-Hip Oil Prevents Oil Oxidation and Allows Obtainment of Gel and Film Topical Formulations.

    PubMed

    Contri, Renata V; Kulkamp-Guerreiro, Irene C; da Silva, Sheila Janine; Frank, Luiza A; Pohlmann, Adriana R; Guterres, Silvia S

    2016-08-01

    The rose-hip oil holds skin regenerating properties with applications in the dermatological and cosmetic area. Its nanoencapsulation might favor the oil stability and its incorporation into hydrophilic formulations, besides increasing the contact with the skin and prolonging its effect. The aim of the present investigation was to develop suitable rose-hip-oil-loaded nanocapsules, to verify the nanocapsule effect on the UV-induced oxidation of the oil and to obtain topical formulations by the incorporation of the nanocapsules into chitosan gel and film. The rose-hip oil (500 or 600 μL), polymer (Eudragit RS100®, 100 or 200 mg), and acetone (50 or 100 mL) contents were separately varied aiming to obtain an adequate size distribution. The results led to a combination of the factors acetone and oil. The developed formulation showed average diameter of 158 ± 6 nm with low polydispersity, pH of 5.8 ± 0.9, zeta potential of +9.8 ± 1.5 mV, rose-hip oil content of 54 ± 1 μL/mL and tendency to reversible creaming. No differences were observed in the nanocapsules properties after storage. The nanoencapsulation of rose-hip oil decreased the UVA and UVC oxidation of the oil. The chitosan gel and film containing rose-hip-oil-loaded nanocapsules showed suitable properties for cutaneous use. In conclusion, it was possible to successfully obtain rose-hip-oil-loaded nanocapsules and to confirm the nanocapsules effect in protecting the oil from the UV rays. The chitosan gel and film were considered interesting alternatives for incorporating the nanoencapsulated rose-hip oil, combining the advantages of the nanoparticles to the advantages of chitosan.

  11. Magnetic {Mo72Fe30}-embedded hybrid nanocapsules.

    PubMed

    Cui, Jiwei; Fan, Dawei; Hao, Jingcheng

    2009-02-15

    Magnetic nanocapsules were constructed by fabricating nanometer scaled C(60)-like "Keplerate" type {Mo(72)Fe(30)} with molecular formula [Mo(72)(VI)Fe(30)(III)O(252)(CH(3)COO)(12){Mo(2)O(7)(H(2)O)}(2){H(2)Mo(2)O(8)(H(2)O)}(H(2)O)(91)] x ca.150 H(2)O into nanocapsule shells using the LbL technique. The morphology of the obtained hybrid nanocapsules was examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Shell thickness of the {Mo(72)Fe(30)}-embedded nanocapsules can be tailored at the nanometer level more precisely than other nanoparticle-embedded capsules due to the homogeneous diameter and surface charges of {Mo(72)Fe(30)}. Interestingly, the {Mo(72)Fe(30)}-embedded nanocapsules could be separated and aligned under a circumstance of magnetic field, though {Mo(72)Fe(30)} is a paramagnetic molecule. This is the first time to fabricate hybrid magnetic materials containing {Mo(72)Fe(30)} using LbL technique. The obtained nanocapsules can be a good candidate for bioseparation as well as targeted delivery.

  12. Highly fluorescent resorcinarene cavitand nanocapsules with efficient renal clearance

    NASA Astrophysics Data System (ADS)

    Mahadevan, Kalpana; Patthipati, Venkata Suresh; Han, Sangbum; Swanson, R. James; Whelan, Eoin C.; Osgood, Christopher; Balasubramanian, Ramjee

    2016-08-01

    Nanomaterial based imaging approaches hold substantial promise in addressing current diagnostic and therapeutic challenges. One of the key requirements for the successful clinical translation of nanomaterials is their complete clearance from the body within a reasonable time period preferably via the renal filtration route. This article describes the synthesis of highly fluorescent, water soluble, resorcinarene cavitand nanocapsules and demonstrates their effective renal clearance in mice. The synthesis and functionalization of nanocapsules was accomplished in a one-pot operation via thiol-ene reactions without involving self-assembly, sacrificial templates or emulsions. Water soluble resorcinarene cavitand nanocapsules obtained by this approach were covalently functionalized with Alexa Fluor 750. Highly fluorescent nanocapsules with hydrodynamic diameters of 122 nm and 68 nm and extinction coefficients of 1.3 × 109 M-1 cm-1 and 1.5 × 108 M-1 cm-1 respectively were prepared by varying the reaction conditions. The in vivo biodistribution and clearance of these nanocapsules in mice followed by whole-body fluorescence imaging showed that they were both cleared renally within a few hours. Given the inherent encapsulation capabilities of nanocapsules, the renal clearance demonstrated in this work opens up new opportunities for their theranostic applications especially for targeting and treating the urinary tract.

  13. Highly fluorescent resorcinarene cavitand nanocapsules with efficient renal clearance.

    PubMed

    Mahadevan, Kalpana; Patthipati, Venkata Suresh; Han, Sangbum; Swanson, R James; Whelan, Eoin C; Osgood, Christopher; Balasubramanian, Ramjee

    2016-08-19

    Nanomaterial based imaging approaches hold substantial promise in addressing current diagnostic and therapeutic challenges. One of the key requirements for the successful clinical translation of nanomaterials is their complete clearance from the body within a reasonable time period preferably via the renal filtration route. This article describes the synthesis of highly fluorescent, water soluble, resorcinarene cavitand nanocapsules and demonstrates their effective renal clearance in mice. The synthesis and functionalization of nanocapsules was accomplished in a one-pot operation via thiol-ene reactions without involving self-assembly, sacrificial templates or emulsions. Water soluble resorcinarene cavitand nanocapsules obtained by this approach were covalently functionalized with Alexa Fluor 750. Highly fluorescent nanocapsules with hydrodynamic diameters of 122 nm and 68 nm and extinction coefficients of 1.3 × 10(9) M(-1) cm(-1) and 1.5 × 10(8) M(-1) cm(-1) respectively were prepared by varying the reaction conditions. The in vivo biodistribution and clearance of these nanocapsules in mice followed by whole-body fluorescence imaging showed that they were both cleared renally within a few hours. Given the inherent encapsulation capabilities of nanocapsules, the renal clearance demonstrated in this work opens up new opportunities for their theranostic applications especially for targeting and treating the urinary tract.

  14. Lipid nanocapsules: a new platform for nanomedicine.

    PubMed

    Huynh, N T; Passirani, C; Saulnier, P; Benoit, J P

    2009-09-11

    Nanomedicine, an emerging new field created by the fusion of nanotechnology and medicine, is one of the most promising pathways for the development of effective targeted therapies with oncology being the earlier and the most notable beneficiary to date. Indeed, drug-loaded nanoparticles provide an ideal solution to overcome the low selectivity of the anticancer drugs towards the cancer cells in regards to normal cells and the induced severe side-effects, thanks to their passive and/or active targeting to cancer tissues. Liposome-based systems encapsulating drugs are already used in some cancer therapies (e.g. Myocet, Daunoxome, Doxil). But liposomes have some important drawbacks: they have a low capacity to encapsulate lipophilic drugs (even though it exists), they are manufactured through processes involving organic solvents, and they are leaky, unstable in biological fluids and more generally in aqueous solutions for being commercialized as such. We have developed new nano-cargos, the lipid nanocapsules, with sizes below the endothelium fenestration (phi<100 nm), that solve these disadvantages. They are prepared according to a solvent-free process and they are stable for at least one year in suspension ready for injection, which should reduce considerably the cost and convenience for treatment. Moreover, these new nano-cargos have the ability to encapsulate efficiently lipophilic drugs, offering a pharmaceutical solution for their intravenous administration. The lipid nanocapsules (LNCs) have been prepared according to an original method based on a phase-inversion temperature process recently developed and patented. Their structure is a hybrid between polymeric nanocapsules and liposomes because of their oily core which is surrounded by a tensioactive rigid membrane. They have a lipoprotein-like structure. Their size can be adjusted below 100 nm with a narrow distribution. Importantly, these properties confer great stability to the structure (physical stability

  15. Development and Optimization of Polymeric Self-Emulsifying Nanocapsules for Localized Drug Delivery: Design of Experiment Approach

    PubMed Central

    Wadhwa, Jyoti; Asthana, Abhay; Gupta, Sumeet; Shilkari Asthana, Gyati; Singh, Ranjit

    2014-01-01

    The purpose of the present study was to formulate polymeric self-emulsifying curcumin nanocapsules with high encapsulation efficiency, good emulsification ability, and optimal globule size for localized targeting in the colon. Formulations were prepared using modified quasiemulsion solvent diffusion method. Concentration of formulation variables, namely, X 1 (oil), X 2 (polymeric emulsifier), and X 3 (adsorbent), was optimized by design of experiments using Box-Behnken design, for its impact on mean globule size (Y 1) and encapsulation efficiency (Y 2) of the formulation. Polymeric nanocapsules with an average diameter of 100–180 nm and an encapsulation efficiency of 64.85 ± 0.12% were obtained. In vitro studies revealed that formulations released the drug after 5 h lag time corresponding to the time to reach the colonic region. Pronounced localized action was inferred from the plasma concentration profile (C max 200 ng/mL) that depicts limited systemic absorption. Roentgenography study confirms the localized presence of carrier (0–2 h in upper GIT; 2–4 h in small intestine; and 4–24 h in the lower intestine). Optimized formulation showed significantly higher cytotoxicity (IC50 value 20.32 μM) in HT 29 colonic cancer cell line. The present study demonstrates systematic development of polymeric self-emulsifying nanocapsule formulation of curcumin for localized targeting in colon. PMID:25525620

  16. Development and optimization of polymeric self-emulsifying nanocapsules for localized drug delivery: design of experiment approach.

    PubMed

    Wadhwa, Jyoti; Asthana, Abhay; Gupta, Sumeet; Shilkari Asthana, Gyati; Singh, Ranjit

    2014-01-01

    The purpose of the present study was to formulate polymeric self-emulsifying curcumin nanocapsules with high encapsulation efficiency, good emulsification ability, and optimal globule size for localized targeting in the colon. Formulations were prepared using modified quasiemulsion solvent diffusion method. Concentration of formulation variables, namely, X1 (oil), X2 (polymeric emulsifier), and X3 (adsorbent), was optimized by design of experiments using Box-Behnken design, for its impact on mean globule size (Y1) and encapsulation efficiency (Y2) of the formulation. Polymeric nanocapsules with an average diameter of 100-180 nm and an encapsulation efficiency of 64.85±0.12% were obtained. In vitro studies revealed that formulations released the drug after 5 h lag time corresponding to the time to reach the colonic region. Pronounced localized action was inferred from the plasma concentration profile (C max 200 ng/mL) that depicts limited systemic absorption. Roentgenography study confirms the localized presence of carrier (0-2 h in upper GIT; 2-4 h in small intestine; and 4-24 h in the lower intestine). Optimized formulation showed significantly higher cytotoxicity (IC50 value 20.32 μM) in HT 29 colonic cancer cell line. The present study demonstrates systematic development of polymeric self-emulsifying nanocapsule formulation of curcumin for localized targeting in colon.

  17. Amphiphilic beta-cyclodextrins modified on the primary face: synthesis, characterization, and evaluation of their potential as novel excipients in the preparation of nanocapsules.

    PubMed

    Memişoğlu, Erem; Bochot, Amélie; Sen, Murat; Charon, Daniel; Duchêne, Dominique; Hincal, A Atilla

    2002-05-01

    The purpose of this study was to synthesize and characterize amphiphilic beta-cyclodextrins modified on the primary face with substituents of varying chain lengths (C6 and C14) and bond types (ester or amide). We also aimed to evaluate the potentiality of the new amphiphilic beta-cyclodextrins as excipients for the preparation and optimization of nanocapsules without using surface-active agents. Amphiphilic beta-cyclodextrin derivatives were characterized by (1)H-nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, mass spectroscopy, differential scanning calorimetry, and elemental analysis. Nanocapsules prepared by nanoprecipitation were characterized by particle size and zeta potential determination and freeze fracture followed by transmission electron microscopy. The appropriate amphiphilic beta-cyclodextrin and its optimum concentration to be used were determined. Formation and characteristics of the nanocapsules were highly dependent on the structural properties of the modified cyclodextrin, its behavior in the oil-water interface and the viscosity and miscibility of the organic solvent with water. Physical stability after 5-month storage was also evaluated. The results indicated that derivatives with 6C aliphatic chains on the primary face proved to be the most efficient among the amphiphilic beta-CDs in this study. They avoid the use of surfactants in parenteral formulations of nanocapsules. Copyright 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association

  18. Emulsion-core and polyelectrolyte-shell nanocapsules: biocompatibility and neuroprotection against SH-SY5Y cells

    NASA Astrophysics Data System (ADS)

    Piotrowski, Marek; Szczepanowicz, Krzysztof; Jantas, Danuta; Leśkiewicz, Monika; Lasoń, Władysław; Warszyński, Piotr

    2013-11-01

    The emulsion-core and polyelectrolyte-coated nanocapsules, designed as water-insoluble neuroprotective drug delivery system, were synthesized using layer-by-layer saturation method. The isopropyl myristate was used as oil phase and docusate sodium salt as emulsifier. For the polyelectrolyte shell preparation, synthetic polyelectrolytes, cationic (PDADMAC, PAH, and PLL) and anionic (PGA) were used. The particle size and zeta potential of nanocapsules were characterized by the dynamic light scattering. The average size of synthesized nanocapsules ranged from 80 to 100 nm. Zeta potential values ranged from less than approximately -30 mV for the polyanion layers to greater than approximately +30 mV for the polycation layers. Biocompatibilities of the synthesized nanocarriers were evaluated against SH-SY5Y human neuroblastoma cells using various biochemical assays. The results obtained show that synthesized nanocapsules coated with PLL and PGA were nontoxic to SH-SY5Y cells, and they were used as nanocarriers for model neuroprotective drug (a calpain inhibitor MDL 28170). The neuroprotective action of the encapsulated MDL 28170 against hydrogen peroxide-induced oxidative stress cytotoxicity was evaluated in the same cell line. The results showed that nanoencapsulated form of MDL 28170 were biocompatible and protected SH-SY5Y cells against the H2O2 (0.5 mM/24 h)-induced damage in 20-40 times lower concentrations than those of the same drug added directly to the culture medium. These data suggest that the nanoscale carriers of neuroprotective drugs might serve as novel promising therapeutic agents for oxidative stress-related neurodegenerative processes.

  19. New Curcumin-Loaded Chitosan Nanocapsules: In Vivo Evaluation.

    PubMed

    Marin, Edgar; Briceño, Maria Isabel; Torres, Alicia; Caballero-George, Catherina

    2017-03-06

    The medicinal applications of curcumin, the major component of Curcuma longa, are limited by its poor solubility and low oral bioavailability. In order to overcome this limitation, a method to produce nanocapsules of chitosan loaded with curcumin was developed. Three different molecular weight and deacetylation degree chitosan polymers were used in the formulation in order to prepare curcumin-loaded nanocapsules (mass ratio 1 : 1.4). The best results were achieved using chitosan-Bi with a molecular weight of 710 000 Da. A bimodal distribution was observed in samples; moreover, chitosan-Bi produced the lowest particle size (197 nm). The entrapment efficacy of all chitosan nanocapsules produced reached values between 75 and 92 %. Their rate of drug release at different pH levels (2.0 and 7.4) showed a fast onset of curcumin release. Swiss mice were used to determine oral and total bioavailability of the new curcumin-loaded nanocapsules. Remarkably, the bioavailability of curcumin nanoformulated increased 9-fold compared with no formulated curcumin. These nanocapsules have the ability to cross the blood-brain barrier, and its production is an easy to scale-up procedure using nontoxic materials.

  20. Controlling Properties and Cytotoxicity of Chitosan Nanocapsules by Chemical Grafting

    PubMed Central

    De Matteis, Laura; Alleva, Maria; Serrano-Sevilla, Inés; García-Embid, Sonia; Stepien, Grazyna; Moros, María; de la Fuente, Jesús M.

    2016-01-01

    The tunability of the properties of chitosan-based carriers opens new ways for the application of drugs with low water-stability or high adverse effects. In this work, the combination of a nanoemulsion with a chitosan hydrogel coating and the following poly (ethylene glycol) (PEG) grafting is proven to be a promising strategy to obtain a flexible and versatile nanocarrier with an improved stability. Thanks to chitosan amino groups, a new easy and reproducible method to obtain nanocapsule grafting with PEG has been developed in this work, allowing a very good control and tunability of the properties of nanocapsule surface. Two different PEG densities of coverage are studied and the nanocapsule systems obtained are characterized at all steps of the optimization in terms of diameter, Z potential and surface charge (amino group analysis). Results obtained are compatible with a conformation of PEG molecules laying adsorbed on nanoparticle surface after covalent linking through their amino terminal moiety. An improvement in nanocapsule stability in physiological medium is observed with the highest PEG coverage density obtained. Cytotoxicity tests also demonstrate that grafting with PEG is an effective strategy to modulate the cytotoxicity of developed nanocapsules. Such results indicate the suitability of chitosan as protective coating for future studies oriented toward drug delivery. PMID:27706041

  1. Rational design of protamine nanocapsules as antigen delivery carriers.

    PubMed

    González-Aramundiz, José Vicente; Presas, Elena; Dalmau-Mena, Inmaculada; Martínez-Pulgarín, Susana; Alonso, Covadonga; Escribano, José M; Alonso, María J; Csaba, Noemi Stefánia

    2017-01-10

    Current challenges in global immunization indicate the demand for new delivery strategies, which could be applied to the development of new vaccines against emerging diseases, as well as to improve safety and efficacy of currently existing vaccine formulations. Here, we report a novel antigen nanocarrier consisting of an oily core and a protamine shell, further stabilized with pegylated surfactants. These nanocarriers, named protamine nanocapsules, were rationally designed to promote the intracellular delivery of antigens to immunocompetent cells and to trigger an efficient and long-lasting immune response. Protamine nanocapsules have nanometric size, positive zeta potential and high association capacity for H1N1 influenza hemagglutinin, a protein that was used here as a model antigen. The new formulation shows an attractive stability profile both, as an aqueous suspension or a freeze-dried powder formulation. In vitro studies showed that protamine nanocapsules were efficiently internalized by macrophages without eliciting significant toxicity. In vivo studies indicate that antigen-loaded nanocapsules trigger immune responses comparable to those achieved with alum, even when using significantly lower antigen doses, thus indicating their adjuvant properties. These promising in vivo data, alongside with their versatility for the loading of different antigens and oily immunomodulators and their excellent stability profile, make these nanocapsules a promising platform for the delivery of antigens.

  2. Nanocapsules with glycerol monolaurate: Effects on Candida albicans biofilms.

    PubMed

    Lopes, Leonardo Quintana Soares; Santos, Cayane Genro; Vaucher, Rodrigo de Almeida; Raffin, Renata Platcheck; Santos, Roberto Christ Vianna

    2016-08-01

    Candida albicans does not only occur in the free living planktonic form but also grows in surface-attached biofilm communities. Moreover, these biofilms appear to be the most common lifestyle and are involved in the majority of human Candida infections. Nanoparticles can be used as an alternative to conventional antimicrobial agents and can also act as carriers for antibiotics and other drugs. In view of this, the aim of the study was develop, characterize and verify the anti-biofilm potential of GML Nanocapsules against C. albicans. The GML Nanocapsules showed mean diameter of 193.2 nm, polydispersion index of 0.044, zeta potential of -23.3 mV and pH 6.32. The microdilution assay showed MIC of 15.5 μg mL(-1) to GML Nanocapsules and 31.25 μg mL(-1) to GML. The anti-biofilm assay showed the significantly reduction of biomass of C. albicans biofilm treated with GML Nanocapsules while the GML does not exhibit effect. The kinetic assay demonstrated that at 48 h, the GML Nanocapsules reduce 94% of formed biofilm. The positive results suggest the promisor alternative for this public health problem that is biofilm infections.

  3. Biomaterial properties evaluation of poly(vinyl acetate- alt-maleic anhydride)/chitosan nanocapsules

    NASA Astrophysics Data System (ADS)

    Raţă, Delia Mihaela; Popa, Marcel; Chailan, Jean-François; Zamfir, Carmen Lăcrămioara; Peptu, Cătălina Anişoara

    2014-08-01

    Nanocapsules with diameter around 100 nm based on a natural polymer (chitosan) and a synthetic polymer poly(vinyl acetate- alt-maleic anhydride) [poly(MAVA)] by interfacial condensation method were prepared. The present study proposes a new type of biocompatible nanocapsules based on poly(vinyl acetate- alt-maleic anhydride-chitosan) (MCS) able to become a reliable support for inclusion and release of drugs. The spherical shape of the nanocapsules was evidenced by scanning electron microscopy. Nanocapsules presented a good Norfloxacin loading and release capacity. Haemocompatibility tests have demonstrated that the nanocapsules present a low toxicity and a good compatibility with sanguine medium. The biocompatibility properties of the nanocapsules after their intraperitoneal administration in rats were evidenced by histopathological examination of different organs (brain, liver, kidney, and lung). The results are encouraging and the nanocapsules can be used as controlled drug delivery systems.

  4. Nanocapsules: The Weapons for Novel Drug Delivery Systems

    PubMed Central

    Kothamasu, Pavankumar; Kanumur, Hemanth; Ravur, Niranjan; Maddu, Chiranjeevi; Parasuramrajam, Radhika; Thangavel, Sivakumar

    2012-01-01

    Introduction Nanocapsules, existing in miniscule size, range from 10 nm to 1000 nm. They consist of a liquid/solid core in which the drug is placed into a cavity, which is surrounded by a distinctive polymer membrane made up of natural or synthetic polymers. They have attracted great interest, because of the protective coating, which are usually pyrophoric and easily oxidized and delay the release of active ingredients. Methods Various technical approaches are utilized for obtaining the nanocapsules; however, the methods of interfacial polymerization for monomer and the nano-deposition for preformed polymer are chiefly preferred. Most important characteristics in their preparation is particle size and size distribution which can be evaluated by using various techniques like X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolu¬tion transmission electron microscopy, X-ray photoelectron spectroscopy, superconducting quantum interference device, multi angle laser light scattering and other spectroscopic techniques. Results Nanocapsules possessing extremely high reproducibility have a broad range of life science applications. They may be applied in agrochemicals, genetic engineering, cosmetics, cleansing products, wastewater treatments, adhesive component applications, strategic delivery of the drug in tumors, nanocapsule bandages to fight infec¬tion, in radiotherapy and as liposomal nanocapsules in food science and agriculture. In addition, they can act as self-healing materials. Conclusion The enhanced delivery of bio¬active molecules through the targeted delivery by means of a nanocapsule opens numerous challenges and opportunities for the research and future development of novel improved therapies. PMID:23678444

  5. Uptake of PEGylated indocyanine green loaded nanocapsules by cells of reticuloendothelial system

    NASA Astrophysics Data System (ADS)

    Bahmani, Baharak; Gupta, Sharad; Vullev, Valentine; Anvari, Bahman

    2011-03-01

    Optically active nanoparticles are widely pursued as exogenous chromophores in diagnostic imaging and phototherapeutic applications. However, the blood circulation time of nanoparticles remains limited due to the rapid clearance of the nanoparticles by reticuloendothelial system (RES). Coating with Polyethylene glycol (PEG) is a strategy to extend the circulation time of nanoparticles. Here, we report synthesis and cellular studies of polymeric-based nanocapsules loaded with Indocyanine green (ICG), an FDA approved near-infrared dye, and coated with PEG molecules of various molecular weights through reductive amination. We report the effect of PEG's molecular weight on the uptake of these nanocapsules by human spleen macrophages and hepatocytes using flow cytometry. Our results indicate that the phagocytic content of PEGylated nanocapsules in human spleen macrophages was reduced as compared to uncoated nanocapsules. Among PEGylated nanocapsules, low molecular weight (5000 Da) PEG-coated nanocapsules displayed lower intracellular uptake by spleen macrophages than high molecular weight (30,000 Da) PEG-coated nanocapsules for up to 90 minutes. Encapsulation within the polymeric nanocapsules reduced the hepatic content of ICG with normal human hepatocytes for up to two hours, while the molecular weight of PEG did not have a statistically significant effect on the content of the nanocapsules in liver cells. Our results suggest that reduced uptake of nanocapsules by RES cells can result in prolonged blood circulation time of these nanoconstructs.

  6. Intracellular Trafficking Network of Protein Nanocapsules: Endocytosis, Exocytosis and Autophagy

    PubMed Central

    Zhang, Jinxie; Zhang, Xudong; Liu, Gan; Chang, Danfeng; Liang, Xin; Zhu, Xianbing; Tao, Wei; Mei, Lin

    2016-01-01

    The inner membrane vesicle system is a complex transport system that includes endocytosis, exocytosis and autophagy. However, the details of the intracellular trafficking pathway of nanoparticles in cells have been poorly investigated. Here, we investigate in detail the intracellular trafficking pathway of protein nanocapsules using more than 30 Rab proteins as markers of multiple trafficking vesicles in endocytosis, exocytosis and autophagy. We observed that FITC-labeled protein nanoparticles were internalized by the cells mainly through Arf6-dependent endocytosis and Rab34-mediated micropinocytosis. In addition to this classic pathway: early endosome (EEs)/late endosome (LEs) to lysosome, we identified two novel transport pathways: micropinocytosis (Rab34 positive)-LEs (Rab7 positive)-lysosome pathway and EEs-liposome (Rab18 positive)-lysosome pathway. Moreover, the cells use slow endocytosis recycling pathway (Rab11 and Rab35 positive vesicles) and GLUT4 exocytosis vesicles (Rab8 and Rab10 positive) transport the protein nanocapsules out of the cells. In addition, protein nanoparticles are observed in autophagosomes, which receive protein nanocapsules through multiple endocytosis vesicles. Using autophagy inhibitor to block these transport pathways could prevent the degradation of nanoparticles through lysosomes. Using Rab proteins as vesicle markers to investigation the detail intracellular trafficking of the protein nanocapsules, will provide new targets to interfere the cellular behaver of the nanoparticles, and improve the therapeutic effect of nanomedicine. PMID:27698943

  7. Retinyl palmitate flexible polymeric nanocapsules: characterization and permeation studies.

    PubMed

    Teixeira, Zaine; Zanchetta, Beatriz; Melo, Bruna A G; Oliveira, Luciana L; Santana, Maria H A; Paredes-Gamero, Edgar J; Justo, Giselle Z; Nader, Helena B; Guterres, Sílvia S; Durán, Nelson

    2010-11-01

    Polymeric nanocapsules with elastic characteristics were prepared by the pre-formed polymer interfacial deposition method. The system consists of an oily core of retinyl palmitate with Span 60 and a polymeric wall of poly(D,L-lactide) (PLA). A narrow size distribution (215 nm, P.D.I. 0.10) was showed by dynamic light scattering (DLS) analyses. Particle deformability was observed by transmission electron microscopy (TEM) images and permeation of the particles through two superposed membranes of smaller pore diameters. Permeation studies were achieved using plastic surgery abdominal human skin by Franz diffusion cell. Retinyl palmitate permeates into deep skin layers. Besides, a PLA fluorescent derivative conjugated with Nile blue dye by an amide covalent bound was additionally obtained. Permeation profile of the nanocapsules with the fluorescent polymer was evaluated by confocal laser scanning microscopy (CLSM). The CLSM showed that nanocapsules were distributed uniformly, suggesting that the permeation mechanism through skin is intercellular. Thus, the use of these nanocapsules may be a feasible strategy to enhance the permeation of actives into the skin when delivery to deep layers is aimed.

  8. Personality in frozen shoulder

    PubMed Central

    Fleming, A.; Dodman, Sally; Beer, T. C.; Crown, S.

    1976-01-01

    Fleming, A., Dodman, S., Beer, T. C., and Crown, S. (1976).Annals of the Rheumatic Diseases, 35, 456-457. Personality in frozen shoulder. Fifty-six patients with frozen shoulder have had their personality profiles investigated by means of the Middlesex Hospital Questionnaire. Females showed significantly increased somatic anxiety compared with controls. It is suggested that this may be important both to aetiology and treatment. Males and females should be assessed separately in future studies of frozen shoulder. PMID:1234412

  9. Surface active properties of lipid nanocapsules

    PubMed Central

    Mouzouvi, Celia R. A.; Bigot, André K.; Saulnier, Patrick

    2017-01-01

    Lipid nanocapsules (LNCs) are biomimetic nanocarriers used for the encapsulation of a broad variety of active ingredients. Similar to surface active compounds, LNCs contain both hydrophilic and hydrophobic parts in their structure. Moreover, the components of LNCs, macrogol 15 hydroxystearate (MHS) and lecithin, are known for their surface active properties. Therefore, the aim of this paper was to investigate the capability of the LNCs to decrease surface tension using two techniques: drop tensiometry and the Wilhelmy plate method. LNCs with diameters ranging from 30 to 100 nm were successfully obtained using a phase inversion technique. The LNCs’ properties, such as size and zeta potential, depend on the composition. LNCs exhibit a lower limiting surface tension compared to MHS (34.8–35.0 mN/m and 37.7–38.8 mN/m, respectively), as confirmed by both drop tensiometry and the Wilhelmy plate method. LNCs have exhibited a saturated interfacial concentration (SIC) that was 10-fold higher than the critical micellar concentration (CMC) of MHS or the SIC of binary and ternary mixtures of LNC ingredients. The SIC of the LNC formulations depended on the mass mixing ratio of the MHS/triglycerides but not on the presence of lecithin. The CMC/SIC values measured by the Wilhelmy plate method were higher than those obtained using drop tensiometry because of the longer duration of the tensiometry measurement. In conclusion, the surfactant-like properties of the LNCs offer new possibilities for medical and pharmaceutical applications. PMID:28796777

  10. Tragacanth gum as a natural polymeric wall for producing antimicrobial nanocapsules loaded with plant extract.

    PubMed

    Ghayempour, Soraya; Montazer, Majid; Mahmoudi Rad, Mahnaz

    2015-11-01

    Tragacanth gum as a biocompatible and biodegradable polymer with good properties including emulsifying, viscosity and cross-linking ability can be used as the wall material in encapsulation of different compounds, specifically plant extracts. In this paper, for the first time, Tragacanth gum was used to produce nanocapsules containing plant extract through microemulsion method. The effect of different parameters on the average size of prepared nanocapsules in presence of aluminum and calcium chloride through ultrasonic and magnetic stirrer was investigated. The high efficient nanocapsules were prepared with spherical shape and smooth surface. The average size of nanocapsules prepared through ultrasonic using aluminum chloride (22nm) was smaller than other products. The structure of prepared nanocapsules was studied by FT-IR spectroscopy. Antimicrobial activity of different nanocapsules against Escherichia coli, Staphylococcus aureus and Candida albicans was investigated by shake flask method during their release showed 100% microbial reduction after 12h stirring.

  11. Encapsulation of curcumin in polyelectrolyte nanocapsules and their neuroprotective activity

    NASA Astrophysics Data System (ADS)

    Szczepanowicz, Krzysztof; Jantas, Danuta; Piotrowski, Marek; Staroń, Jakub; Leśkiewicz, Monika; Regulska, Magdalena; Lasoń, Władysław; Warszyński, Piotr

    2016-09-01

    Poor water solubility and low bioavailability of lipophilic drugs can be potentially improved with the use of delivery systems. In this study, encapsulation of nanoemulsion droplets was utilized to prepare curcumin nanocarriers. Nanosize droplets containing the drug were encapsulated in polyelectrolyte shells formed by the layer-by-layer (LbL) adsorption of biocompatible polyelectrolytes: poly-L-lysine (PLL) and poly-L-glutamic acid (PGA). The size of synthesized nanocapsules was around 100 nm. Their biocompatibility and neuroprotective effects were evaluated on the SH-SY5Y human neuroblastoma cell line using cell viability/toxicity assays (MTT reduction, LDH release). Statistically significant toxic effect was clearly observed for PLL coated nanocapsules (reduction in cell viability about 20%-60%), while nanocapsules with PLL/PGA coating did not evoke any detrimental effects on SH-SY5Y cells. Curcumin encapsulated in PLL/PGA showed similar neuroprotective activity against hydrogen peroxide (H2O2)-induced cell damage, as did 5 μM curcumin pre-dissolved in DMSO (about 16% of protection). Determination of concentration of curcumin in cell lysate confirmed that curcumin in nanocapsules has cell protective effect in lower concentrations (at least 20 times) than when given alone. Intracellular mechanisms of encapsulated curcumin-mediated protection engaged the prevention of the H2O2-induced decrease in mitochondrial membrane potential (MMP) but did not attenuate Reactive Oxygen Species (ROS) formation. The obtained results indicate the utility of PLL/PGA shell nanocapsules as a promising, alternative way of curcumin delivery for neuroprotective purposes with improved efficiency and reduced toxicity.

  12. Encapsulation of curcumin in polyelectrolyte nanocapsules and their neuroprotective activity.

    PubMed

    Szczepanowicz, Krzysztof; Jantas, Danuta; Piotrowski, Marek; Staroń, Jakub; Leśkiewicz, Monika; Regulska, Magdalena; Lasoń, Władysław; Warszyński, Piotr

    2016-09-02

    Poor water solubility and low bioavailability of lipophilic drugs can be potentially improved with the use of delivery systems. In this study, encapsulation of nanoemulsion droplets was utilized to prepare curcumin nanocarriers. Nanosize droplets containing the drug were encapsulated in polyelectrolyte shells formed by the layer-by-layer (LbL) adsorption of biocompatible polyelectrolytes: poly-L-lysine (PLL) and poly-L-glutamic acid (PGA). The size of synthesized nanocapsules was around 100 nm. Their biocompatibility and neuroprotective effects were evaluated on the SH-SY5Y human neuroblastoma cell line using cell viability/toxicity assays (MTT reduction, LDH release). Statistically significant toxic effect was clearly observed for PLL coated nanocapsules (reduction in cell viability about 20%-60%), while nanocapsules with PLL/PGA coating did not evoke any detrimental effects on SH-SY5Y cells. Curcumin encapsulated in PLL/PGA showed similar neuroprotective activity against hydrogen peroxide (H2O2)-induced cell damage, as did 5 μM curcumin pre-dissolved in DMSO (about 16% of protection). Determination of concentration of curcumin in cell lysate confirmed that curcumin in nanocapsules has cell protective effect in lower concentrations (at least 20 times) than when given alone. Intracellular mechanisms of encapsulated curcumin-mediated protection engaged the prevention of the H2O2-induced decrease in mitochondrial membrane potential (MMP) but did not attenuate Reactive Oxygen Species (ROS) formation. The obtained results indicate the utility of PLL/PGA shell nanocapsules as a promising, alternative way of curcumin delivery for neuroprotective purposes with improved efficiency and reduced toxicity.

  13. Controlled 2D Assembly of Nickel-Seamed Hexameric Pyrogallol[4]arene Nanocapsules.

    PubMed

    Zhang, Chen; Patil, Rahul S; Liu, Chong; Barnes, Charles L; Atwood, Jerry L

    2017-03-01

    The two-dimensional framework of nickel-seamed hexameric metal-organic nanocapsules has been synthesized by connecting the tailed hydroxyl groups of C-propan-3-ol pyrogallol[4]arene with adjacent hexameric capsules via nickel-hydroxyl coordination. In addition, functionalization of nanocapsules with multiple pyridine molecules at the capsule surface prevents them from assembling into hierarchical structures and leads to the formation of discrete nickel-seamed pyrogallol[4]arene nanocapsules. This work shows that surface functionalization of nanocapsules is an effective and innovative method of controlling the assembly of these nanometric building blocks.

  14. Haloperidol-loaded polysorbate-coated polymeric nanocapsules decrease its adverse motor side effects and oxidative stress markers in rats.

    PubMed

    Benvegnú, Dalila Moter; Barcelos, Raquel Cristine Silva; Boufleur, Nardeli; Pase, Camila Simonetti; Reckziegel, Patrícia; Flores, Fernanda Cramer; Ourique, Aline Ferreira; Nora, Magali Dalla; da Silva, Cristiane de Bona; Beck, Ruy Carlos Ruver; Bürger, Marilise Escobar

    2012-10-01

    Haloperidol is the most widely used antipsychotic drug in the treatment of psychiatric disorders. Despite its satisfactory therapeutic effect, its chronic use is related to severe motor side effects. Here, we investigate the incidence of motor side effects of haloperidol-loaded nanocapsules when compared to free haloperidol and the relation with oxidative stress (OS) development. Both vehicle (B-NcFO) and haloperidol loaded polysorbate-coated nanocapsules suspension (H-NcFO) prepared with fish oil as core showed uniform and rounded particles, nanometric size, negative zeta potential, low polydispersity indices and high encapsulation efficiency. Wistar rats received a single dose of free haloperidol (FH), B-NcFO or H-NcFO (0.2 mg/kg ip) and were submitted to acute motor side effects evaluation 1 h after the injection. Lower catalepsy time and oral dyskinesia were observed in H-NcFO-treated group than in FH group; however, both formulations decreased animals' locomotor activity. In a experiment performed subchronically, rats injected daily with H-NcFO (0.2 mg/kg-ip) for 28 days showed decreased oral dyskinesia frequency and catalepsy time and no impairment on locomotor activity as compared to FH group (0.2 mg/kg-ip). FH group showed higher OS, as observed by increased lipid peroxidation and reduced glutathione levels and catalase activity in extrapyramidal region. Our findings showed that nanocapsules may be an efficient form to prevent or minimize haloperidol motor side effects, which are related to OS development, ameliorating psychiatric patients' quality of life. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Optimization and preparation of nanocapsules for food applications using two methodologies.

    PubMed

    Esmaeili, Akbar; Gholami, Masoomeh

    2015-07-15

    This study investigated preparation of nanocapsules (NCs) containing food-grade ingredients using two experimental designs: a one-factor-at-a-time method (OFATM) and an optimization method (OM). Response surface methodology (RSM) was used to optimize the process. The variables explored were concentration and type of polymer wall, using polycaprolactone (PCL) and polyethylene glycol-polybutylene adipate-polyethylene glycol (PEG-PBA-PEG) (1.0-4.0 mg) polyester triblock copolymer; food oil, using olive and avocado oil (0.5-2.0 mg); solvent, using acetone and ethyl acetate (6-12 ml); and surfactant concentration, using Tween 80 and Tween 60 (1-5 mg). The optimum conditions to obtain NCs were found to be 2.0 mg of PCL and 1.65 mg of PEG-PBA-PEG, olive oil (0.5 and 0.88 mg), acetone (6 and 10.25 ml), and Tween 60 (3.0 and 4.25 mg), with 90.9 and 71.9 nm for OFATM and OM, respectively. This research was conducted to investigate the use of NCs in the manufacture of fruits. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Passively Targeted Curcumin-Loaded PEGylated PLGA Nanocapsules for Colon Cancer Therapy In Vivo

    PubMed Central

    Klippstein, Rebecca; Wang, Julie Tzu-Wen; El-Gogary, Riham I; Bai, Jie; Mustafa, Falisa; Rubio, Noelia; Bansal, Sukhvinder; Al-Jamal, Wafa T; Al-Jamal, Khuloud T

    2015-01-01

    Clinical applications of curcumin for the treatment of cancer and other chronic diseases have been mainly hindered by its short biological half-life and poor water solubility. Nanotechnology-based drug delivery systems have the potential to enhance the efficacy of poorly soluble drugs for systemic delivery. This study proposes the use of poly(lactic-co-glycolic acid) (PLGA)-based polymeric oil-cored nanocapsules (NCs) for curcumin loading and delivery to colon cancer in mice after systemic injection. Formulations of different oil compositions are prepared and characterized for their curcumin loading, physico-chemical properties, and shelf-life stability. The results indicate that castor oil-cored PLGA-based NC achieves high drug loading efficiency (≈18% w(drug)/w(polymer)%) compared to previously reported NCs. Curcumin-loaded NCs internalize more efficiently in CT26 cells than the free drug, and exert therapeutic activity in vitro, leading to apoptosis and blocking the cell cycle. In addition, the formulated NC exhibits an extended blood circulation profile compared to the non-PEGylated NC, and accumulates in the subcutaneous CT26-tumors in mice, after systemic administration. The results are confirmed by optical and single photon emission computed tomography/computed tomography (SPECT/CT) imaging. In vivo growth delay studies are performed, and significantly smaller tumor volumes are achieved compared to empty NC injected animals. This study shows the great potential of the formulated NC for treating colon cancer. PMID:26140363

  17. Chlorhexidine Nanocapsule Drug Delivery Approach to the Resin-Dentin Interface.

    PubMed

    Priyadarshini, B M; Selvan, S T; Lu, T B; Xie, H; Neo, J; Fawzy, A S

    2016-08-01

    In this study, we are introducing a new drug-delivery approach to demineralized dentin substrates through microsized dentinal tubules in the form of drug-loaded nanocapsules. Chlorhexidine (CHX) is widely used in adhesive dentistry due to its nonspecific matrix metalloproteinase inhibitory effect and antibacterial activities. Poly(ε-caprolactone) nanocapsules (nano-PCL) loaded with CHX were fabricated by interfacial polymer deposition at PCL/CHX ratios of 125:10, 125:25, and 125:50. Unloaded nanocapsules (blank) were fabricated as control. The fabricated nanocapsules were characterized in vitro in terms of particle size, surface charges, particle recovery, encapsulation efficiency, and drug loading. Nanocapsule morphology, drug inclusion, structural properties, and crystallinity were investigated by scanning and transmission electron microscopes (SEM/TEM), energy-dispersive x-ray analysis, Fourier transform infrared spectroscopy, and x-ray diffraction. Initial screening of the antibacterial activities and the cytotoxicity of the nanocapsules were also conducted. Nanocapsules, as carried on ethanol/water solution, were delivered to demineralized dentin specimens connected to an ex vivo model setup simulating the pulpal pressure to study their infiltration, penetration depth, and retention inside the dentinal tubules by SEM/TEM. Nanocapsules were Ag labeled and delivered to demineralized dentin, followed by the application of a 2-step etch-and-rinse dentin adhesive. CHX-release profiles were characterized in vitro and ex vivo up to 25 d. Spherical nanocapsules were fabricated with a CHX core coated with a thin PCL shell. The blank nanocapsules exhibited the largest z-average diameter with negatively charged ζ-potential. With CHX incorporation, the nanocapsule size was decreased with a positive shift in ζ-potential. Nano-PCL/CHX at 125:50 showed the highest drug loading, antibacterial effect, and CHX release both in vitro and ex vivo. SEM and TEM revealed the deep

  18. Dissolution of iron oxide nanoparticles inside polymer nanocapsules.

    PubMed

    Möller, Johannes; Cebi, Melek; Schroer, Martin A; Paulus, Michael; Degen, Patrick; Sahle, Christoph J; Wieland, D C Florian; Leick, Sabine; Nyrow, Alexander; Rehage, Heinz; Tolan, Metin

    2011-12-07

    The structure of poly(organosiloxane) nanocapsules partially filled with iron oxide cores of different sizes was revealed by small angle X-ray scattering and X-ray diffraction. The nanocapsules are synthesized by the formation of a poly(organosiloxane) shell around iron oxide nanoparticles and the simultaneous partial dissolution of these cores. Due to the high scattering contrast of the iron oxide cores compared to the polymer shell, the particle size distribution of the cores inside the capsules can be measured by small angle X-ray scattering. Additional information can be revealed by X-ray diffraction, which gives insights into the formation of the polymer network and the structure of the iron oxide cores. The study shows how the crystallinity and size of the nanoparticles as well as the shape and width of the size distribution can be altered by the synthesis parameters.

  19. Recent progress in the preparation and application of carbon nanocapsules

    NASA Astrophysics Data System (ADS)

    Hwang, Kuo Chu

    2010-09-01

    In this review paper, the processes for the fabrication of carbon nanoparticles, carbon nanospheres, carbon onions, onion-like carbons and metal-filled carbon nanocapsules are reviewed. These processes include carbon arc discharge, metal catalysed chemical vapour deposition, thermal pyrolysis of organometallics and nanodiamonds, electric arc in liquid (e.g. liquid N2, H2O and organic solvents), and microwave arcing. The applications of both hollow and metal-filled carbon nanocapsules/nanoparticles as x-ray target materials, nanolubricants, broadband electromagnetic wave absorbers, catalysts for organic reactions, electrode materials for batteries and electrochemical immunoassays, biomedical gene/drug transporters, etc are also reviewed. The future prospects are also discussed.

  20. Reversible PH Lability of Cross-Linked Vault Nanocapsules

    SciTech Connect

    Yu, M.; Ng, B.C.; Rome, L.H.; Tolbert, S.H.; Monbouquette, H.G.

    2009-05-28

    Vaults are ubiquitous, self-assembled protein nanocapsules with dimension in the sub-100 nm range that are conserved across diverse phyla from worms to humans. Their normal presence in humans at a copy number of over 10 000/cell makes them attractive as potential drug delivery vehicles. Toward this goal, bifunctional amine-reactive reagents are shown to be useful for the reversible cross-linking of recombinant vaults such that they may be closed and opened in a controllable manner.

  1. Biocompatible lutein-polymer-lipid nanocapsules: Acute and subacute toxicity and bioavailability in mice.

    PubMed

    Ranganathan, Arunkumar; Hindupur, Ravi; Vallikannan, Baskaran

    2016-12-01

    Lutein-poly-(lactic-co-glycolic acid) (PLGA)-phospholipid (PL) nanocapsules were prepared (henceforth referred as lutein nanocapsules) and studied for acute, subacute oral toxicity and bioavailability of lutein in mice. Prior to examining the safety of lutein nanocapsules, particle size, zeta potential, surface morphology and interaction between lutein, PLGA and PL were studied. In acute study, mice were gavaged with a single dose of lutein nanocapsules at 0.1, 1, 10 and 100mg/kg body weight (BW) and examined for 2weeks, while in subacute study, daily mice were gavaged with a dose of 1 and 10mg/kg BW for 4weeks. Results revealed that mean size and zeta value of lutein nanocapsules were 140nm and -44mV, respectively. Acute and subacute toxicity studies did not show any mortality or treatment related adverse effect in clinical observations, ophthalmic examinations, body and organ weights. No toxicity related findings were observed in hematology, histopathology and other blood and tissue clinical chemistry parameters. In subacute study, no observed adverse effect level (NOAEL) of lutein nanocapsules was found to be at a dose of 10mg/kg BW. Feeding lutein nanocapsules resulted in a significant (p<0.01) increase in lutein level in plasma and tissue compared to the control group. Lutein nanocapsules did not cause toxicity in mice. However, human trials are warranted. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Preparation and characterization of degradable nanocapsules that release pesticides over an extended period of time

    USDA-ARS?s Scientific Manuscript database

    Pesticide efficacy is limited by evaporation and precipitation. These processes can result in the need for costly pesticide re-application. By using a nanocapsule to contain the pesticide, these two problems can be greatly reduced. Produced nanocapsules adsorb on the surface of the plant and are not...

  3. Designing calcium phosphate-based bifunctional nanocapsules with bone-targeting properties

    NASA Astrophysics Data System (ADS)

    Khung, Yit-Lung; Bastari, Kelsen; Cho, Xing Ling; Yee, Wu Aik; Loo, Say Chye Joachim

    2012-06-01

    Using sodium dodecyl sulphate micelles as template, hollow-cored calcium phosphate nanocapsules were produced. The surfaces of the nanocapsule were subsequently silanised by a polyethylene glycol (PEG)-based silane with an N-hydroxysuccinimide ester end groups which permits for further attachment with bisphosphonates (BP). Characterisations of these nanocapsules were investigated using Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy, Fourier Transform Infra-Red Spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Dynamic Light Scattering. To further validate the bone-targeting potential, dentine discs were incubated with these functionalised nanocapsules. FESEM analysis showed that these surface-modified nanocapsules would bind strongly to dentine surfaces compared to non-functionalised nanocapsules. We envisage that respective components would give this construct a bifunctional attribute, whereby (1) the shell of the calcium phosphate nanocapsule would serve as biocompatible coating aiding in gradual osteoconduction, while (2) surface BP moieties, acting as targeting ligands, would provide the bone-targeting potential of these calcium phosphate nanocapsules.

  4. Selol-loaded magnetic nanocapsules: A new approach for hyperthermia cancer therapy

    NASA Astrophysics Data System (ADS)

    Falqueiro, A. M.; Primo, F. L.; Morais, P. C.; Mosiniewicz-Szablewska, E.; Suchocki, P.; Tedesco, A. C.

    2011-04-01

    Polylactic-co-glycolic nanocapsules, loaded with nanosized magnetic particles and Selol (a selenium-based anticancer drug), were successfully prepared by the precipitation method. Maghemite (γ-Fe2O3) nanoparticles were incorporated into the nanocapsules using a highly stable ionic magnetic fluid sample. The obtained nanocapsules presented no agglomeration, negative surface charge while revealing a narrow monomodal size distribution. All the nanocapsule formulations exhibited a good physical stability at 4 °C during 3 month storage period. The in vitro antitumoral activity of Selol-magnetic nanocapsules was assessed using a murine melanoma cell line. The influence of nanocapsules on cell viability was investigated by spectrophotometric assay. The results demonstrated that Selol-loaded magnetic nanocapsules (at 100 μg/ml/5 × 109 particle/ml) showed antitumoral activity of 50% on melanoma cells (absence of magnetic field). These results clearly indicate that the loaded nanocapsules represent a novel and promising magnetic drug delivery system suitable for cancer treatment via the active drug and magnetohyperthermia.

  5. Evaluation of photodynamic activity, photostability and in vitro drug release of zinc phthalocyanine-loaded nanocapsules.

    PubMed

    de Souza, Thiane Deprá; Ziembowicz, Francieli Isa; Müller, Debora Friedrich; Lauermann, Sâmera Cristina; Kloster, Carmen Luisa; Santos, Roberto Christ Vianna; Lopes, Leonardo Quintana Soares; Ourique, Aline Ferreira; Machado, Giovanna; Villetti, Marcos Antonio

    2016-02-15

    Nanocapsule formulations containing zinc phthalocyanine (ZnPc) were investigated as drug delivery systems for use in photodynamic therapy (PDT). ZnPc loaded chitosan, PCL, and PCL coated with chitosan nanocapsules were prepared and characterized by means of their physicochemical properties, photodynamic activity, photostability and drug release profile. All formulations presented nanometric hydrodynamic radius, around 100 nm, low polydispersity index (0.08-0.24), slightly negative zeta potential for PCL nanoparticles and positive zeta potential for suspension containing chitosan. Encapsulation efficiencies were higher than 99%. The capacity of ZnPc loaded nanocapsules to produce cytotoxic singlet oxygen ((1)O2) by irradiation with red laser was monitored using 1.3-diphenylisobenzofuran as a probe. The singlet oxygen quantum yields (ΦΔ) for ZnPc loaded chitosan nanocapsules were high and similar to that of the standard (ZnPc in DMSO), displaying excellent ability to generate (1)O2. The photosensitizer loaded nanocapsules are photostable in the timescale usually utilized in PDT and only a small photobleaching event was observed when a light dose of 610J/cm(2) was applied. The in vitro drug release studies of ZnPc from all nanocapsules demonstrated a sustained release profile controlled by diffusion, without burst effect. The nature of the polymer and the core type of the nanocapsules regulated ZnPc release. Thus, the nanocapsules developed in this work are a promising strategy to be employed in PDT. Copyright © 2015. Published by Elsevier B.V.

  6. Biodegradable Polymeric Nanocapsules Prevent Cardiotoxicity of Anti-Trypanosomal Lychnopholide

    PubMed Central

    Branquinho, Renata Tupinambá; Roy, Jérôme; Farah, Charlotte; Garcia, Giani Martins; Aimond, Franck; Le Guennec, Jean-Yves; Saude-Guimarães, Dênia Antunes; Grabe-Guimaraes, Andrea; Mosqueira, Vanessa Carla Furtado; de Lana, Marta; Richard, Sylvain

    2017-01-01

    Chagas disease is a neglected parasitic disease caused by the protozoan Trypanosoma cruzi. New antitrypanosomal options are desirable to prevent complications, including a high rate of cardiomyopathy. Recently, a natural substance, lychnopholide, has shown therapeutic potential, especially when encapsulated in biodegradable polymeric nanocapsules. However, little is known regarding possible adverse effects of lychnopholide. Here we show that repeated-dose intravenous administration of free lychnopholide (2.0 mg/kg/day) for 20 days caused cardiopathy and mortality in healthy C57BL/6 mice. Echocardiography revealed concentric left ventricular hypertrophy with preserved ejection fraction, diastolic dysfunction and chamber dilatation at end-stage. Single cardiomyocytes presented altered contractility and Ca2+ handling, with spontaneous Ca2+ waves in diastole. Acute in vitro lychnopholide application on cardiomyocytes from healthy mice also induced Ca2+ handling alterations with abnormal RyR2-mediated diastolic Ca2+ release. Strikingly, the encapsulation of lychnopholide prevented the cardiac alterations induced in vivo by the free form repeated doses. Nanocapsules alone had no adverse cardiac effects. Altogether, our data establish lychnopholide presented in nanocapsule form more firmly as a promising new drug candidate to cure Chagas disease with minimal cardiotoxicity. Our study also highlights the potential of nanotechnology not only to improve the efficacy of a drug but also to protect against its adverse effects. PMID:28349937

  7. Intracellular Delivery of Bioactive Molecules using Light-Addressable Nanocapsules

    PubMed Central

    Gregersen, Kimberly A. D.; Hill, Zachary B.; Gadd, Jennifer C.; Fujimoto, Bryant S.; Maly, Dustin J.; Chiu, Daniel T.

    2010-01-01

    This paper describes a method by which molecules that are impermeable to cells are encapsulated in dye-sensitized lipid nanocapsules for delivery into cells via endocytosis. Once inside the cells, the molecules are released from the lipid nanocapsules into the cytoplasm with a single nanosecond pulse from a laser in the far red (645nm). We demonstrate this method with the intracellular release of the second messenger IP3 in CHO-M1 cells, and report that calcium responses from the cells changed from a sustained increase to a transient spike when the average number of IP3 released is decreased below 50 molecules per nanocapsule. We also demonstrate the delivery of a 23 kDa AGT fusion protein into Ba/F3 cells to inhibit a key player BCR-ABL in the apoptotic pathway. We show that an average of ~ 8 molecules of the inhibitor is sufficient to induce apoptosis in the majority of Ba/F3 cells. PMID:21117640

  8. Gold nanoshelled liquid perfluorocarbon nanocapsules for combined dual modal ultrasound/CT imaging and photothermal therapy of cancer.

    PubMed

    Ke, Hengte; Yue, Xiuli; Wang, Jinrui; Xing, Sen; Zhang, Qian; Dai, Zhifei; Tian, Jie; Wang, Shumin; Jin, Yushen

    2014-03-26

    The integration of multimodal contrast-enhanced diagnostic imaging and therapeutic capabilities could utilize imaging guided therapy to plan the treatment strategy based on the diagnostic results and to guide/monitor the therapeutic procedures. Herein, gold nanoshelled perfluorooctylbromide (PFOB) nanocapsules with PEGylation (PGsP NCs) are constructed by oil-in-water emulsion method to form polymeric PFOB nanocapsules, followed by the formation of PEGylated gold nanoshell on the surface. PGsP NCs could not only provide excellent contrast enhancement for dual modal ultrasound and CT imaging in vitro and in vivo, but also serve as efficient photoabsorbers for photothermal ablation of tumors on xenografted nude mouse model. To our best knowledge, this is the first report of gold nanoshell serving as both CT contrast agents and photoabsorbers for photothermal therapy. The novel multifunctional nanomedicine would be of great value to offer more comprehensive diagnostic information to guide more accurate and effective cancer therapy. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Nanocapsules for drug delivery through the skin barrier by tissue-tolerable plasma

    NASA Astrophysics Data System (ADS)

    Lademann, J.; Patzelt, A.; Richter, H.; Lademann, O.; Baier, G.; Breucker, L.; Landfester, K.

    2013-08-01

    For many years, several attempts have been made to enhance skin penetration by chemical, physical or mechanical manipulation to reduce the barrier function of the skin. The present study demonstrates the possibility of penetration enhancement for 400 nm sized nanocapsules loaded with a model drug consisting of a fluorescent dye by the application of tissue-tolerable plasma (TTP). Therefore, the stability of the nanocapsules and their penetration through the skin barrier prior to and in combination with TTP application was evaluated. The results revealed that the penetration of the nanocapsules could be effectively enhanced when applied in combination with TTP, hence delivering the model drug unaffected by plasma into deeper skin layers. The stability testing showed no significant structural changes of the nanocapsules after contact with TTP. Thus, the present study introduces a new strategy for the penetration enhancement of substances by the combined utilization of nanocapsules and TTP.

  10. High doses of lipid-core nanocapsules do not affect bovine embryonic development in vitro.

    PubMed

    Lucas, Caroline G; Remião, Mariana H; Bruinsmann, Franciele A; Lopes, Isadora A R; Borges, Morgana A; Feijó, Ana Laura S; Basso, Andrea Cristina; Pohlmann, Adriana R; Guterres, Silvia S; Campos, Vinicius F; Seixas, Fabiana K; Collares, Tiago

    2017-09-18

    The improvement of in vitro embryo production by culture media supplementation has been a potential tool to increase blastocyst quality and development. Recently, lipid-core nanocapsules (LNC), which were developed for biomedical applications as a drug-delivery system, have demonstrated beneficial effects on in vitro embryo production studies. LNCs have a core composed of sorbitan monostearate dispersed in capric/caprylic triglyceride. Based on that, we firstly investigated if LNCs supplemented during in vitro oocyte maturation had affinity to the mineral oil placed over the top of the IVM media. Also, the effects of LNC supplementation in different concentrations (0; 0.94; 4.71; 23.56; 117.80 and 589.00μg/mL) during the in vitro maturation protocol were evaluated in oocytes and blastocysts by in vitro tests. LNCs seemed not to migrate to the mineral oil overlay during the in vitro oocyte maturation. Interestingly, LNCs did not show toxic effects in the oocyte in vitro maturation rate, cumulus cells expansion and oocyte viability. The highest LNCs concentration tested (589μg/mL) generated the lowest ROS and GSH levels, and reduced apoptosis rate when compared to the control. Additionally, toxic effects in embryo development and quality were not observed. The LNC supramolecular structure demonstrated to be a promising nanocarrier to deliver molecules in oocytes and embryos, aiming the improvement of the embryo in vitro development. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Encapsulation of Homogeneous Catalysts in Porous Polymer Nanocapsules Produces Fast-Acting Selective Nanoreactors.

    PubMed

    Dergunov, Sergey A; Khabiyev, Alibek T; Shmakov, Sergey N; Kim, Mariya D; Ehterami, Nasim; Weiss, Mary Clare; Birman, Vladimir B; Pinkhassik, Eugene

    2016-12-27

    Nanoreactors were created by entrapping homogeneous catalysts in hollow nanocapsules with 200 nm diameter and semipermeable nanometer-thin shells. The capsules were produced by the polymerization of hydrophobic monomers in the hydrophobic interior of the bilayers of self-assembled surfactant vesicles. Controlled nanopores in the shells of nanocapsules ensured long-term retention of the catalysts coupled with the rapid flow of substrates and products in and out of nanocapsules. The study evaluated the effect of encapsulation on the catalytic activity and stability of five different catalysts. Comparison of kinetics of five diverse reactions performed in five different solvents revealed the same reaction rates for free and encapsulated catalysts. Identical reaction kinetics confirmed that placement of catalysts in the homogeneous interior of polymer nanocapsules did not compromise catalytic efficiency. Encapsulated organometallic catalysts showed no loss of metal ions from nanocapsules suggesting stabilization of the complexes was provided by nanocapsules. Controlled permeability of the shells of nanocapsules enabled size-selective catalytic reactions.

  12. Growth-Factor Nanocapsules That Enable Tunable Controlled Release for Bone Regeneration.

    PubMed

    Tian, Haijun; Du, Juanjuan; Wen, Jing; Liu, Yang; Montgomery, Scott R; Scott, Trevor P; Aghdasi, Bayan; Xiong, Chengjie; Suzuki, Akinobu; Hayashi, Tetsuo; Ruangchainikom, Monchai; Phan, Kevin; Weintraub, Gil; Raed, Alobaidaan; Murray, Samuel S; Daubs, Michael D; Yang, Xianjin; Yuan, Xu-Bo; Wang, Jeffrey C; Lu, Yunfeng

    2016-08-23

    Growth factors are of great potential in regenerative medicine. However, their clinical applications are largely limited by the short in vivo half-lives and the narrow therapeutic window. Thus, a robust controlled release system remains an unmet medical need for growth-factor-based therapies. In this research, a nanoscale controlled release system (degradable protein nanocapsule) is established via in situ polymerization on growth factor. The release rate can be finely tuned by engineering the surface polymer composition. Improved therapeutic outcomes can be achieved with growth factor nanocapsules, as illustrated in spinal cord fusion mediated by bone morphogenetic protein-2 nanocapsules.

  13. The Frozen Price Game

    ERIC Educational Resources Information Center

    Alden, Lori

    2003-01-01

    In this article, the author discusses the educational frozen price game she developed to teach the basic economic principle of price allocation. In addition to demonstrating the advantages of price allocation, the game also illustrates such concepts as opportunity costs, cost benefit comparisons, and the trade-off between efficiency and equity.…

  14. Fresh Frozen Plasma

    DTIC Science & Technology

    2009-03-01

    therapeutic means). FFP can be prepared either by separation from whole blood or collection via plasmapheresis . Fresh frozen plasma contains the...FFP can be further separated into cryoprecipitate and what is known as “cryo-poor plasma,” a product rarely used for therapeutic means. Plasma is the

  15. Multilayered silica-biopolymer nanocapsules with a hydrophobic core and a hydrophilic tunable shell thickness

    NASA Astrophysics Data System (ADS)

    Vecchione, Raffaele; Luciani, Giuseppina; Calcagno, Vincenzo; Jakhmola, Anshuman; Silvestri, Brigida; Guarnieri, Daniela; Belli, Valentina; Costantini, Aniello; Netti, Paolo A.

    2016-04-01

    Stable, biocompatible, multifunctional and multicompartment nanocarriers are much needed in the field of nanomedicine. Here, we report a simple, novel strategy to design an engineered nanocarrier system featuring an oil-core/hybrid polymer/silica-shell. Silica shells with a tunable thickness were grown in situ, directly around a highly mono-disperse and stable oil-in-water emulsion system, stabilized by a double bio-functional polyelectrolyte heparin/chitosan layer. Such silica showed a complete degradation in a physiological medium (SBF) in a time frame of three days. Moreover, the outer silica shell was coated with polyethyleneglycol (PEG) in order to confer antifouling properties to the final nanocapsule. The outer silica layer combined its properties (it is an optimal bio-interface for bio-conjugations and for the embedding of hydrophilic drugs in the porous structure) with the capability to stabilize the oil core for the confinement of high payloads of lipophilic tracers (e.g. CdSe quantum dots, Nile Red) and drugs. In addition, polymer layers - besides conferring stability to the emulsion while building the silica shell - can be independently exploited if suitably functionalized, as demonstrated by conjugating chitosan with fluorescein isothiocyanate. Such numerous features in a single nanocarrier system make it very intriguing as a multifunctional platform for smart diagnosis and therapy.Stable, biocompatible, multifunctional and multicompartment nanocarriers are much needed in the field of nanomedicine. Here, we report a simple, novel strategy to design an engineered nanocarrier system featuring an oil-core/hybrid polymer/silica-shell. Silica shells with a tunable thickness were grown in situ, directly around a highly mono-disperse and stable oil-in-water emulsion system, stabilized by a double bio-functional polyelectrolyte heparin/chitosan layer. Such silica showed a complete degradation in a physiological medium (SBF) in a time frame of three days

  16. Foods - fresh vs. frozen or canned

    MedlinePlus

    Frozen foods vs. fresh or canned; Fresh foods vs. frozen or canned; Frozen vegetables versus fresh ... a well-balanced diet. Many people wonder if frozen and canned vegetables are as healthy for you ...

  17. Preparation and properties of dysprosium nanocapsules coated with boron, carbon, and dysprosium oxide

    SciTech Connect

    Si, P.Z.; Brueck, E.; Zhang, Z.D.; Skorvanek, I.; Kovac, J.; Zhang, M

    2004-06-08

    Boron-coated dysprosium/dysprosium oxide, carbon-coated dysprosium/DyC{sub 2}, and dysprosium oxide-coated dysprosium nanocapsules were prepared using an arc discharge method in diborane, methane, and argon, respectively. The magnetization of these nanocapsules has been measured at temperatures between 4 and 290 K, in applied fields up to 6 T. The transition temperature of nanocrystalline Dy from the helical phase to the ferromagnetic phase is much lower than that of bulk Dy. The linear temperature dependence of the inverse susceptibility of these nanocapsules, being a mixture of superparamagnetic Dy and paramagnetic dysprosium oxide or carbide, can be explained within the molecular field theory with magnetic moments with the total angular momentum J=15/2 and the Lande factor g=4/3. We discuss the relations between the structure and the magnetization of these nanocapsules.

  18. Synthesis of magnetic and upconversion nanocapsules as multifunctional drug delivery system

    SciTech Connect

    Huang, Shanshan; Chen, Yinyin; Liu, Bei; He, Fei; Ma, Ping’an; Deng, Xiaoran; Cheng, Ziyong Lin, Jun

    2015-09-15

    Multifunctional hollow nanocapsules with magnetic and upconversion luminescence properties were synthesized. Hollow Fe{sub 3}O{sub 4}@SiO{sub 2} was firstly prepared by using rodlike β-FeOOH as the template followed by silica coating, calcinations and reduction. Then Fe{sub 3}O{sub 4}@SiO{sub 2}@α-NaYF{sub 4}:Yb{sup 3+},Er{sup 3+} nanocapsules (FeSiUCNP) were synthesized by the hydrothermal transformation of the Y(Yb{sup 3+}, Er{sup 3+})(OH)CO{sub 3} (YOC) deposited onto the surface of nanocapsules through a urea-assisted homogeneous precipitation method. The hollow nanocapsules with porous structure provide space and entrance for the drug molecules. Due to the outside shell of α-NaYF{sub 4}:Yb{sup 3+}, Er{sup 3+}, the nanomaterial shows upconverting red emission upon 980 nm NIR-light excitation. Moreover, the nanocomposites with hollow magnetite core exhibit a high relaxivity with r{sub 2} value of 183 mM{sup −1} s{sup −1}, which reveal the potential as T{sub 2}-weighted contrast agents for magnetic resonance imaging (MRI). The as-prepared nanocapsules can be performed as anti-cancer drug carriers for investigation of drug loading/release properties, which demonstrated a sustained drug release pattern and a comparable cytotoxicity with free doxorubicin (DOX). The multifunctional nanocapsules incorporated upconverting luminescence, T{sub 2}-weighted MRI imaging and drug targeting delivery modalities have great potential for theranostic applications in cancer treatment. - Graphical abstract: Multifunctional hollow nanocapsules with upconverting luminescence, T{sub 2}-weighted MRI imaging and drug targeting delivery modalities were synthesized for cancer treatment. - Highlights: • Multifunctional porous Fe{sub 3}O{sub 4}@SiO{sub 2}@α-NaYF{sub 4}:Yb{sup 3+},Er{sup 3+} nanocapsules were synthesized. • The nanocapsules show upconverting red emission upon 980 nm NIR-light excitation. • The nanocapsules exihibit potential as T{sub 2}-weighted contrast agents

  19. Clozapine linked to nanocapsules minimizes tissue and oxidative damage to biomolecules lipids, proteins and DNA in brain of rats Wistar.

    PubMed

    da Costa Güllich, Angélica Aparecida; Coelho, Ritiéle Pinto; Pilar, Bruna Cocco; Ströher, Deise Jaqueline; Galarça, Leandro Alex Sander Leal; Vieira, Simone Machado; da Costa Escobar Piccoli, Jacqueline; Haas, Sandra Elisa; Manfredini, Vanusa

    2015-06-01

    Clozapine, atypical antipsychotic, can change oxidative stress parameters. It is known that reactive species, in excess, can have a crucial role in the etiology of diseases, as well as, can potentiating adverse effects induce by drugs. The nanocapsules have attracted attention as carriers of several drugs, with consequent reduction of adverse effects. This study aimed to evaluate histopathology and oxidative damage of biomolecules lipids, proteins and DNA in the brain of Wistar rats after treatment with nanocapsules containing clozapine. The study consisted of eight groups of male Wistar rats (n = 6): saline (SAL), free clozapine (CZP) (25 mg/Kg i.p.), blank uncoated nanocapsules (BNC), clozapine-loaded uncoated nanocapsules (CNC) (25 mg/Kg i.p.), blank chitosan-coated nanocapsules (BCSN), clozapine-loaded chitosan-coated nanocapsules (CCSN) (25 mg/Kg i.p.), blank polyethyleneglycol-coated nanocapsules (BPEGN), clozapine-loaded polyethyleneglycol-coated nanocapsules (CPEGN) (25 mg/Kg i.p.). The animals received the formulation once a day for seven consecutive days and euthanized in the eighth day. After euthanasia, the brain was collected and homogenate was processed for further analysis. The histopathology showed less brain tissue damage in nanocapsules-treated groups. The lipid peroxidation and carbonylation of proteins showed a significant increase (p < 0.05) induced by CZP. CNC and CPEGN groups obtained a reduction membrane of lipids damage and nanocapsules-treated groups showed significant improvement protein damage. CZP was able to induce genetic oxidative damage, while the nanocapsules causing less damage to DNA. The findings show that different coatings can act protecting target tissues decreasing oxidative damage, suggesting that the drug when linked to different nanocapsules is able to mitigate the harmful effects of clozapine.

  20. Core-shell hybrid nanocapsules for oral delivery of camptothecin: formulation development, in vitro and in vivo evaluation

    NASA Astrophysics Data System (ADS)

    Ünal, Hale; d'Angelo, Ivana; Pagano, Ester; Borrelli, Francesca; Izzo, Angelo; Ungaro, Francesca; Quaglia, Fabiana; Bilensoy, Erem

    2015-01-01

    The objective of this study was to design and in vitro-in vivo evaluate oral nanocapsules prepared from amphiphilic cyclodextrins (CDs) or poly-ɛ-caprolactone (PCL) for the effective oral delivery of an anticancer agent, camptothecin (CPT). CPT-loaded anionic and Chitosan (CS)-coated cationic nanocapsules were prepared and characterized in vitro. Morphological analysis was performed by scanning electron microscope (SEM). CPT release profile was evaluated using dialysis method under sink conditions. To determine the protective effect and drug stability provided by nanocapsules, all the formulations were incubated in simulated gastrointestinal media. Measurement of mucoadhesive tendency of CPT-loaded nanocapsules was realized by turbidimetric method. Penetration of nanocapsules was performed through an artificial mucus model. The permeability of CPT in solution form and bound to nanocapsule formulations were demonstrated across Caco-2 cell line. Finally, the intestinal uptake of nanocapsules was evaluated in vivo, in a mouse model. Both anionic and cationic formulations were in the range of 180-220 nm with a narrow size distribution and desired zeta potential values. CPT-loaded nanocapsules were found to be stable in simulated gastrointestinal media. Turbidimetric measurements confirmed the interaction between nanoparticles and mucin. Penetration of CPT through an artificial mucus gel layer was higher with CS-coated nanocapsules in accordance with the results obtained from permeability studies across Caco-2 cell line. In vivo animal studies confirmed that the intestinal uptake of nanocapsules was significantly higher with cationic nanocapsules. CPT-loaded positively charged CD nanocapsules might be an attractive and promising treatment for oral chemotherapy.

  1. Curation of Frozen Samples

    NASA Technical Reports Server (NTRS)

    Fletcher, L. A.; Allen, C. C.; Bastien, R.

    2008-01-01

    NASA's Johnson Space Center (JSC) and the Astromaterials Curator are charged by NPD 7100.10D with the curation of all of NASA s extraterrestrial samples, including those from future missions. This responsibility includes the development of new sample handling and preparation techniques; therefore, the Astromaterials Curator must begin developing procedures to preserve, prepare and ship samples at sub-freezing temperatures in order to enable future sample return missions. Such missions might include the return of future frozen samples from permanently-shadowed lunar craters, the nuclei of comets, the surface of Mars, etc. We are demonstrating the ability to curate samples under cold conditions by designing, installing and testing a cold curation glovebox. This glovebox will allow us to store, document, manipulate and subdivide frozen samples while quantifying and minimizing contamination throughout the curation process.

  2. Texture of Frozen Food

    NASA Astrophysics Data System (ADS)

    Wani, Kohmei

    Quantitative determination of textural quality of frozen food due to freezing and storage conditions is complicated,since the texture is consisted of multi-dimensiona1 factors. The author reviewed the importance of texture in food quality and the factors which is proposed by a priori estimation. New classification of expression words of textural properties by subjective evaluation and an application of four elements mechanical model for analysis of physical characteristics was studied on frozen meat patties. Combination of freezing-thawing condition on the subjective properties and physiochemical characteristics of beef lean meat and hamachi fish (Yellow-tail) meat was studied. Change of the plasticity and the deformability of these samples differed by freezing-thawing rate and cooking procedure. Also optimum freezing-thawing condition was differed from specimens.

  3. Ag3PO4 nanoparticle-decorated Ni/C nanocapsules with tunable electromagnetic absorption properties

    NASA Astrophysics Data System (ADS)

    Cui, Caiyun; Zhou, Pingping; Liu, Xianguo; Or, Siu Wing; Ho, S. L.

    2017-05-01

    Core/shell-structured nickel/carbon (Ni/C) nanocapsules with Ag3PO4 nanoparticle decoration (Ag3PO4@Ni/C) are prepared by an arc-discharge process and an ion-exchange process. The Ag3PO4@Ni/C nanocapsules show a clear decoration of Ag3PO4 nanoparticles of 4-20 nm diameter on the C shell of the Ni/C nanocapsules of ˜60 nm diameter. The amount of Ag3PO4 nanoparticles that can be decorated on the Ni/C nanocapsules depends on the volume of Na2HPO4 reactant used in the ion-exchange process. The Ag3PO4@Ni/C nanocapsules demonstrate interestingly high and tunable electromagnetic absorption properties with different amounts of Ag3PO4 nanoparticle decoration in the paraffin-bonded composites over the 2-18 GHz microwave range. The nanocapsules prepared with 100 ml Na2HPO4 exhibit much enhanced dielectric and magnetic losses for an improved electromagnetic impedance match. These result in a large reflection loss (RL) of -31.4 dB at 12.3 GHz for a small absorber thickness of 2.6 mm in conjunction with a very wide effective absorption bandwidth (for RL<-10 dB) of 14 GHz (4-18 GHz) at a wide absorber thickness range of 1.4-5.0 mm.

  4. The performance of PEGylated nanocapsules of perfluorooctyl bromide as an ultrasound contrast agent.

    PubMed

    Díaz-López, Raquel; Tsapis, Nicolas; Santin, Mathieu; Bridal, Sharon Lori; Nicolas, Valérie; Jaillard, Danielle; Libong, Danielle; Chaminade, Pierre; Marsaud, Véronique; Vauthier, Christine; Fattal, Elias

    2010-03-01

    The surface of polymeric nanocapsules used as ultrasound contrast agents (UCAs) was modified with PEGylated phospholipids in order to escape recognition and clearance by the mononuclear phagocyte system and achieve passive tumor targeting. Nanocapsules consisted of a shell of poly(lactide-co-glycolide) (PLGA) encapsulating a liquid core of perfluorooctyl bromide (PFOB). They were decorated with poly(ethylene glycol-2000)-grafted distearoylphosphatidylethanolamine (DSPE-PEG) incorporated in the organic phase before the solvent emulsification-evaporation process. The influence of DSPE-PEG concentration on nanocapsule size, surface charge, morphology, hydrophobicity and complement activation was evaluated. Zeta potential measurements, Hydrophobic interaction chromatography and complement activation provide evidence of DSPE-PEG presence at nanocapsule surface. Electronic microscopy reveals that the core/shell structure is preserved up to 2.64 mg of DSPE-PEG for 100 mg PLGA. In vivo ultrasound imaging was performed in mice bearing xenograft tumor with MIA PaCa-2 cells, either after an intra-tumoral or intravenous injection of nanocapsules. Tumor was observed only after the intra-tumoral injection. Despite the absence of echogenic signal in the tumor after intravenous injection of nanocapsules, histological analysis reveals their accumulation within the tumor tissue demonstrating that tissue distribution is not the unique property required for ultrasound contrast agents to be efficient. (c) 2009 Elsevier Ltd. All rights reserved.

  5. Folic acid-functionalized human serum albumin nanocapsules for targeted drug delivery to chronically activated macrophages.

    PubMed

    Rollett, Alexandra; Reiter, Tamara; Nogueira, Patricia; Cardinale, Massimiliano; Loureiro, Ana; Gomes, Andreia; Cavaco-Paulo, Artur; Moreira, Alexandra; Carmo, Alexandre M; Guebitz, Georg M

    2012-05-10

    Activated synovial macrophages play a key role in Rheumatoid Arthritis (RA). Recent studies have shown that folate receptor beta (FRβ) is specifically expressed by activated macrophages. Therefore a folate-based nanodevice would provide the possibility of delivering therapeutic agents to activated macrophages without affecting normal cells and tissues. This study shows for the first time the sonochemical preparation of HSA nanocapsules avoiding toxic cross linking chemicals and emulsifiers used in other methods. Production of HSA nanocapsules was optimized leading to a diameter of 443.5 ± 9.0 nm and a narrow size distribution indicated by a polydispersity index (PDI) of 0.066 ± 0.080. Nanocapsules were surface modified with folic acid (FA) and the FA content was determined to be 0.38 and 6.42 molecules FA per molecule HSA, depending on the surplus of FA employed. Dynamic light scattering was used to determine size, PDI and zetapotential of the produced nanocapsules before and after surface modification. FA distribution on the surface of HSA nanocapsules was localized three-dimensionally after fluorescence labeling using confocal laser scanning microscopy (CLSM). Furthermore, specific binding and internalization of HSA nanocapsules by FRβ-positive and FRβ-negative macrophages, obtained from human peripheral blood mononuclear cells, was demonstrated by flow cytometry. FRβ-expressing macrophages showed an increased binding for FA-modified capsules compared with those without FA. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Impact of dose and surface features on plasmatic and liver concentrations of biodegradable polymeric nanocapsules.

    PubMed

    Oliveira, Líliam Teixeira; de Paula, Mônica Auxiliadora; Roatt, Bruno Mendes; Garcia, Giani Martins; Silva, Luan Silvestro Bianchini; Reis, Alexandre Barbosa; de Paula, Carina Silva; Vilela, José Mário Carneiro; Andrade, Margareth Spangler; Pound-Lana, Gwenaelle; Mosqueira, Vanessa Carla Furtado

    2017-07-15

    The effect of polymeric nanocapsule dose on plasmatic and liver concentrations 20min after intravenous administration in mice was evaluated. Nanocapsules were prepared with different polymers, namely, poly(D,L-lactide) (PLA), polyethylene glycol-block-poly(D,L-lactide) (PLA-PEG), and PLA with chitosan (PLA-Cs) and compared with a nanoemulsion. These formulations were labelled with a phthalocyanine dye for fluorescent detection. The nanostructures had narrow size distributions upon separation by asymmetric flow field flow fractionation with static and dynamic light scattering detection, with average hydrodynamic diameters in the 130-300nm range, negative zeta potentials, except PLA-Cs nanocapsules, which had a positive zeta potential. Flow cytometry revealed uptake mostly by monocytes and neutrophils in mice and human blood. PLA nanocapsules and the nanoemulsion showed dose-dependent plasma concentrations, where the percentage of plasmatic fluorescence increased with increasing administered dose. In contrast, PLA-PEG nanocapsules led to a dose-independent plasmatic profile. PLA-Cs nanocapsules showed the lowest plasmatic and liver levels of fluorescence at all administered doses and significant intravenous toxicity in mice. This work demonstrates the importance of considering the nanocarrier dose when evaluating pharmacokinetic and biodistribution data and emphasizes the role of surface features in determining the plasmatic and liver concentrations of a poorly soluble lipophilic encapsulated compound. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Serum-stable quantum dot--protein hybrid nanocapsules for optical bio-imaging

    NASA Astrophysics Data System (ADS)

    Lee, Jeong Yu; Nam, Dong Heon; Oh, Mi Hwa; Kim, Youngsun; Choi, Hyung Seok; Jeon, Duk Young; Beum Park, Chan; Nam, Yoon Sung

    2014-05-01

    We introduce shell cross-linked protein/quantum dot (QD) hybrid nanocapsules as a serum-stable systemic delivery nanocarrier for tumor-targeted in vivo bio-imaging applications. Highly luminescent, heavy-metal-free Cu0.3InS2/ZnS (CIS/ZnS) core-shell QDs are synthesized and mixed with amine-reactive six-armed poly(ethylene glycol) (PEG) in dichloromethane. Emulsification in an aqueous solution containing human serum albumin (HSA) results in shell cross-linked nanocapsules incorporating CIS/ZnS QDs, exhibiting high luminescence and excellent dispersion stability in a serum-containing medium. Folic acid is introduced as a tumor-targeting ligand. The feasibility of tumor-targeted in vivo bio-imaging is demonstrated by measuring the fluorescence intensity of several major organs and tumor tissue after an intravenous tail vein injection of the nanocapsules into nude mice. The cytotoxicity of the QD-loaded HSA-PEG nanocapsules is also examined in several types of cells. Our results show that the cellular uptake of the QDs is critical for cytotoxicity. Moreover, a significantly lower level of cell death is observed in the CIS/ZnS QDs compared to nanocapsules loaded with cadmium-based QDs. This study suggests that the systemic tumor targeting of heavy-metal-free QDs using shell cross-linked HSA-PEG hybrid nanocapsules is a promising route for in vivo tumor diagnosis with reduced non-specific toxicity.

  8. Survival of Microflora in Precooked, Frozen Meals During Frozen Storage,

    DTIC Science & Technology

    FOOD PRESERVATION, *FROZEN FOODS , EXPERIMENTAL DATA, BACTERIA, TEST METHODS, FREEZING, MEALS, MILITARY RESEARCH, TABLES(DATA), YEASTS, STORAGE, FOOD , CULTURES(BIOLOGY), FECES, MICROBIOLOGY, STREPTOCOCCUS, MOLDS(ORGANISMS).

  9. Safe storage of radical initiators within a polyaromatic nanocapsule

    NASA Astrophysics Data System (ADS)

    Yamashina, Masahiro; Sei, Yoshihisa; Akita, Munetaka; Yoshizawa, Michito

    2014-08-01

    2,2'-Azobisisobutyronitrile and its derivatives are standard reagents for polymer and organic syntheses that generate radical species on stimuli by light or heat. Radical initiators like the azo compounds are unstable so that they should be kept in the dark at low temperature to avoid photochemical and thermal decomposition as well as accidental explosion. Here we report the spontaneous and quantitative encapsulation of the radical initiators by a supramolecular nanocapsule in aqueous solution. We demonstrate the remarkable stability of the initiators toward light and heat in the well-defined cavity shielded by the polyaromatic capsule shell. The incarcerated and stabilized initiators can be directly utilized for the radical polymerization of olefins on spontaneous release of the initiators from the capsule under the reaction conditions.

  10. Nanocapsules — A Novel Tool for Medicine and Science

    NASA Astrophysics Data System (ADS)

    Krol, Silke; Diaspro, Alberto; Cavalleri, Ornella; Cavanna, Davide; Ballario, Paola; Grimaldi, Benedetto; Filetici, Patrizia; Ornaghi, Prisca; Gliozzi, Alessandra

    The most promising tool for future applications in the field of science as well as in medicine is the use of nanotechnologies. Especially self-assembly systems with tailored properties on a nanometer level fulfil the requirements to nano-organized systems in a satisfactorily manner. Hence the development of so-called nanocapsules prepared by means of Layer-by-Layer technique was a great progress on the way to individual drug delivery systems or nano-sized bioreactors. The preparation of hollow shells for drug delivery use requires polyelectrolytes as well as a charged core that are not cytotoxic. According to this purpose CaCO3 crystals with different shapes were introduced as removable template for capsules with changeable permeability as a result of pH variations. Due to the low toxic potential of the core it could be valuable for applications in human body.

  11. Internalization of Ineffective Platinum Complex in Nanocapsules Renders It Cytotoxic.

    PubMed

    Vrana, Oldrich; Novohradsky, Vojtech; Medrikova, Zdenka; Burdikova, Jana; Stuchlikova, Olga; Kasparkova, Jana; Brabec, Viktor

    2016-02-18

    Anticancer therapy by platinum complexes, based on nanocarrier-based delivery, may offer a new approach to improve the efficacy and tolerability of the platinum family of anticancer drugs. The original rules for the design of new anticancer platinum drugs were affected by the fact that, although cisplatin (cis-[PtCl2 (NH3)2) was an anticancer drug, its isomer transplatin was not cytotoxic. For the first time, it is demonstrated that simple encapsulation of an inactive platinum compound in phospholipid bilayers transforms it into an efficient cytotoxic agent. Notably, the encapsulation of transplatin makes it possible to overcome the resistance mechanisms operating in cancer cells treated with cisplatin and prevents inactivation of transplatin in the extracellular environment. It is also shown that transplatin delivered to the cells in nanocapsules, in contrast to free (nonencapsulated) complex, forms cytotoxic cross-links on DNA.

  12. Polyethylene glycol-based protein nanocapsules for functional delivery of a differentiation transcription factor.

    PubMed

    Biswas, Anuradha; Liu, Ying; Liu, Tianfei; Fan, Guoping; Tang, Yi

    2012-07-01

    Transcription factors (TFs) can direct cell fate by binding to DNA and regulating gene transcription. Controlling the intracellular levels of specific TFs can therefore enable reprogramming of cellular function and differentiation. Direct delivery of recombinant TFs to target cells can thus have widespread therapeutic value, but has remained challenging due to structural fragility of TFs and inefficient membrane transduction. Here we describe the functional delivery of TFs using degradable polymeric nanocapsules to drive cellular differentiation. The nanocapsules were synthesized with poly(ethylene) glycol (PEG)-based monomers and intracellularly-degradable crosslinkers. Physical properties and release kinetics of the nanocapsules were optimized through tuning of monomer and crosslinker ratios to achieve enhanced delivery of cargo destined for the nuclei. The nanocapsules did not display cytotoxicity in primary cell lines up to concentrations of 5 μm. A recombinant myogenic transcription factor, MyoD, was delivered to the nuclei of myoblast cells using degradable nanocapsules to induce myogenic differentiation. MyoD was confirmed to be delivered to the nuclei of myoblasts using confocal microscopy and was demonstrated to be active in transcription through a luciferase-based reporter assay. More importantly, delivered MyoD was able to drive myoblast differentiation as evidenced by the hallmark elongated and multinuclear morphology of myotubes. The activation of downstream cascade was also confirmed through immunostaining of late myogenic markers myogenin and My-HC. The efficiency of differentiation achieved via nanocapsule delivery is significantly higher than that of native MyoD, and is comparable to that of plasmid transfection. The encapsulated MyoD can also withstand prolonged protease treatment and remain functional. The ease of preparation, biocompatibility and effective cargo delivery make the polymeric nanocapsule a useful tool to deliver a variety of

  13. ULTRATHIN FROZEN SECTIONS

    PubMed Central

    Bernhard, W.; Leduc, Elizabeth H.

    1967-01-01

    A relatively simple method for obtaining ultrathin, frozen sections for electron microscopy has been developed. Tissues, cultured cells, and bacteria may be employed. They are fixed in 1.25–4% glutaraldehyde for 1–4 hr, are washed overnight in buffer at 3°C, and are embedded in 20% thiolated gelatin or pure gelatin. Before sectioning they are partially dehydrated in 50% glycerol, frozen in liquid nitrogen on a modified tissue holder, and subsequently maintained at -70°C with dry ice. Finally, they are sectioned very rapidly with glass knives on a slightly modified Porter-Blum MT-1 microtome in a commercial deep-freeze maintained at -35°C and are floated in the trough of the knife on a 40% solution of dimethylsulfoxide (DMSO). The sections are picked up in plastic loops and transferred to distilled water at room temperature for thawing and removal of the DMSO, placed on grids coated with Formvar and carbon, air-dried, and stained with phosphotungstic acid, sodium silicotungstate, or a triple stain of osmium tetroxide, uranyl acetate, and lead. Large flat sections are obtained in which ultrastructural preservation is good. They are particularly useful for cytochemical studies. PMID:4167504

  14. Frozen Carbon Dioxide

    NASA Technical Reports Server (NTRS)

    2005-01-01

    1 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a south polar residual cap landscape, formed in frozen carbon dioxide. There is no place on Earth that one can go to visit a landscape covering thousands of square kilometers with frozen carbon dioxide, so mesas, pits, and other landforms of the martian south polar region are as alien as they are beautiful. The scarps of the south polar region are known from thousands of other MGS MOC images to retreat at a rate of about 3 meters (3 yards) per martian year, indiating that slowly, over the course of the MGS mission, the amount of carbon dioxide in the martian atmosphere has probably been increasing.

    Location near: 86.9oS, 25.5oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  15. Frozen Carbon Dioxide

    NASA Technical Reports Server (NTRS)

    2005-01-01

    1 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a south polar residual cap landscape, formed in frozen carbon dioxide. There is no place on Earth that one can go to visit a landscape covering thousands of square kilometers with frozen carbon dioxide, so mesas, pits, and other landforms of the martian south polar region are as alien as they are beautiful. The scarps of the south polar region are known from thousands of other MGS MOC images to retreat at a rate of about 3 meters (3 yards) per martian year, indiating that slowly, over the course of the MGS mission, the amount of carbon dioxide in the martian atmosphere has probably been increasing.

    Location near: 86.9oS, 25.5oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  16. Size and core content optimization of epoxy nanocapsules by response surface methodology for use in self-healing coatings

    NASA Astrophysics Data System (ADS)

    Khoee, Sepideh; Hosein Payandeh, Seyed; Jafarzadeh, Parinaz; Asadi, Hamed

    2016-08-01

    A model is provided to estimate the effect of different factors on the synthesis of nanocapsules containing epoxy resin. Producing nanocapsules with different sizes and core-contents for different applications is made possible by using this model. The three parameters that have the most important effect on the properties of the nanocapsules: the surfactant concentration, agitation rate and sonication time are selected and the response surface methodology is used to determine the effect of these parameters on the nanocapsule size and core content. These parameters are modified to prepare nanoparticles with a high core content (68.7%) and small size (165 nm). The nanocapsules were stable up to 150 °C and these properties have made them applicable for future use in self-healing coatings and composites. The modified epoxy nanocapsules were mixed with amine-filled nanocapsules and were incorporated in an epoxy coating. This coating was scratched and kept in a corrosive environment and even after 30 days it still showed a high corrosion resistance, proving that the nanocapsules were able to successfully heal the scratches in the coating. After 30 days of immersion in 3.5 wt% NaCl environment, the corrosion resistance of the coating with healing particles was 38 times higher than the pure coating.

  17. 21 CFR 160.110 - Frozen eggs.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Frozen eggs. 160.110 Section 160.110 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.110 Frozen eggs. (a) Frozen eggs, frozen whole eggs, frozen mixed eggs is the food prepared by...

  18. 21 CFR 160.110 - Frozen eggs.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Frozen eggs. 160.110 Section 160.110 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.110 Frozen eggs. (a) Frozen eggs, frozen whole eggs, frozen mixed eggs is the food prepared by...

  19. 21 CFR 160.110 - Frozen eggs.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Frozen eggs. 160.110 Section 160.110 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.110 Frozen eggs. (a) Frozen eggs, frozen whole eggs, frozen mixed eggs is the food prepared by...

  20. 21 CFR 160.110 - Frozen eggs.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Frozen eggs. 160.110 Section 160.110 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.110 Frozen eggs. (a) Frozen eggs, frozen whole eggs, frozen mixed eggs is the food prepared by...

  1. 21 CFR 160.110 - Frozen eggs.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen eggs. 160.110 Section 160.110 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.110 Frozen eggs. (a) Frozen eggs, frozen whole eggs, frozen mixed eggs is the food prepared by...

  2. 21 CFR 158.170 - Frozen peas.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Frozen peas. 158.170 Section 158.170 Food and... CONSUMPTION FROZEN VEGETABLES Requirements for Specific Standardized Frozen Vegetables § 158.170 Frozen peas. (a) Identity—(1) Product definition. Frozen peas is the food in “package” form as that term...

  3. Formulation development, stability and anticancer efficacy of core-shell cyclodextrin nanocapsules for oral chemotherapy with camptothecin.

    PubMed

    Ünal, Hale; Öztürk, Naile; Bilensoy, Erem

    2015-01-01

    The aim of this study was to design and evaluate hybrid cyclodextrin (CD) nanocapsules intended for the oral delivery of the anticancer agent camptothecin (CPT) in order to maintain drug stability in the body and to improve its eventual bioavailability. For this reason, an amphiphilic cyclodextrin (CD) derivative per-modified on the primary face 6OCAPRO was used as core molecule to form nanocapsules with the nanoprecipitation technique. Nanocapsules were further coated with the cationic polymer chitosan to improve the cellular uptake and interaction with biological membranes through positive surface charge. Nanocapsules were evaluated for their in vitro characteristics such as particle size, zeta potential, drug loading and release profiles followed by cell culture studies with the MCF-7 and Caco-2 cell line evaluating their anticancer efficacy and permeability. The CD nanocapsules were imaged by scanning electron microscopy (SEM). The concentration of CPT entrapped in nanocapsules was determined by reversed phase HPLC. The in vitro release study of CPT was performed with a dialysis bag method under sink conditions mimicking the gastric and intestinal pH. The hydrolytic stability of CPT in nanocapsules was investigated in simulated gastric and intestinal fluids (SGF, SIF). The mean particle sizes of both anionic and cationic CPT-loaded nanocapsules were in the range of 180-200 nm with polydispersity indices lower than 0.400 indicating monodisperse size distribution of nanocapsules with favourable potential for intracellular drug delivery to tumour cells. Surface charges of anionic and cationic nanocapsules were demonstrated as -21 mV and +18 mV, respectively. The stability of CPT in simulated release media, SGF and SIF were maintained suggesting the improved protection of the drug molecule from rapid hydrolysis degradation or gastrointestinal pH in nanocapsule oily core. Furthermore CD nanocapsules showed higher anticancer efficacy than CPT solution against the MCF

  4. Doxorubicin Delivery Using pH and Redox Dual-Responsive Hollow Nanocapsules with a Cationic Electrostatic Barrier

    PubMed Central

    Teranishi, Ryoma; Matsuki, Ryota; Yuba, Eiji; Harada, Atsushi; Kono, Kenji

    2016-01-01

    For the delivery of doxorubicin (DOX), pH and redox dual responsive hollow nanocapsules were prepared through the stabilization of polymer vesicles, which spontaneously formed from polyamidoamine dendron-poly(l-lysine) (PAMAM dendron-PLL), by the introduction of disulfide (SS) bonds between PLLs. The SS-bonded nanocapsules exhibited a very slow release of DOX under an extracellular environment because the cationic PLL membrane acted as an electrostatic barrier against the protonated DOX molecules. However, increasing the glutathione concentration to the intracellular level facilitated the immediate release of DOX through the collapse of nanocapsules by the spontaneous cleavage of SS bonds. SS-bonded nanocapsules also escaped from the endosome by the buffering effect of PAMAM dendrons, and DOX delivery into the cytoplasm was achieved. Furthermore, DOX molecules delivered by SS-bonded nanocapsules exhibited an effective in vitro anticancer effect to HeLa cells. PMID:28042818

  5. Enzyme responsive hyaluronic acid nanocapsules containing polyhexanide and their exposure to bacteria to prevent infection.

    PubMed

    Baier, Grit; Cavallaro, Alex; Vasilev, Krasimir; Mailänder, Volker; Musyanovych, Anna; Landfester, Katharina

    2013-04-08

    Antibacterial nanodevices could bring coatings of plastic materials and wound dressings a big step forward if the release of the antibacterial agents could be triggered by the presence of the bacteria themselves. Here, we show that novel hyaluronic acid (HA)-based nanocapsules containing the antimicrobial agent polyhexanide are specifically cleaved in the presence of hyaluronidase, a factor of pathogenicity and invasion for bacteria like Staphylococcus aureus and Escherichia coli. This resulted in an efficient killing of the pathogenic bacteria by the antimicrobial agent. The formation of different polymeric nanocapsules was achieved through a polyaddition reaction in inverse miniemulsion. After the synthesis, the nanocapsules were transferred to an aqueous medium and investigated in terms of size, size distribution, functionality, and morphology using dynamic light scattering, zeta potential measurements and scanning electron microscopy. The enzyme triggered release of a model dye and the antimicrobial polyhexanide was monitored using fluorescence and UV spectroscopy. The stability of the nanocapsules in several biological media was tested and the interaction of nanocapsules with human serum protein was studied using isothermal titration calorimetry. The antibacterial effectiveness is demonstrated by determination of the antibacterial activity and determination of the minimal bactericidal concentration (MBC).

  6. A new potential nano-oncological therapy based on polyamino acid nanocapsules.

    PubMed

    Gonzalo, Teresa; Lollo, Giovanna; Garcia-Fuentes, Marcos; Torres, Dolores; Correa, Juan; Riguera, Ricardo; Fernandez-Megia, Eduardo; Calvo, Pilar; Avilés, Pablo; Guillén, Maria José; Alonso, Maria José

    2013-07-10

    A critical objective in cancer therapy is to reduce the systemic toxicity through the modification of the biodistribution of anticancer drugs. Herein, we disclose a new biodegradable nanocarrier, polyglutamic acid (PGA) nanocapsules, and present the in vivo pharmacokinetics/toxicity proof-of-concept for the anticancer drug plitidepsin. These novel nanocapsules were prepared using a modified solvent displacement technique where the polyamino acid was electrostatically deposited onto the lipid core. The nanocapsules exhibited an average size of 200 nm, a negative zeta potential and a great capacity for the encapsulation of plitidepsin (encapsulation efficiency above 90%). In addition, the nanocapsules could be freeze-dried and showed an adequate stability profile upon storage. Finally, the in vivo proof-of-concept studies performed in mice indicated that the encapsulation provided the drug with a prolonged blood circulation and a significantly reduced toxicity. In fact, the maximum tolerated dose of the nanoencapsulated drug was more than 3 times that of the reference formulation (Cremophor® EL plitidepsin solution). Overall, beyond the value of this specific formulation, the work reported here represents the evidence of the potential of polyamino acid nanocapsules in nano-oncological therapy.

  7. Laser photolysis of dye-sensitized nanocapsules occurs via a photothermal pathway.

    PubMed

    Dendramis, Kimberly A; Chiu, Daniel T

    2009-11-25

    Light-addressable nanocapsules offer a powerful method for delivering spatiotemporally precise signals to cells. Thus far, the mechanism involved in the photolysis of nanocapsules has been opaque. This paper presents experimental evidence that rules out a photochemical pathway in favor of a photothermal mechanism in the far-red photolysis of dye-sensitized, lipid-vesicle based nanocapsules. Photolysis efficiency was unaffected by the presence of radical inhibitors, and mass spectrometry measurements confirmed that the photolytic process did not produce dye radicals. Measurements of dye quantum yield in the lipid membrane showed an inverse correlation between quantum yield of the dye and photolysis efficiency of the vesicle. The result is consistent with the notion that a decrease in quantum yield translates into more vibrational relaxation and thermal motion of the dye molecules in the membrane and thus more efficient photothermal disruption of the vesicle. Furthermore, we observed that the decrease in quantum yield and increase in photolysis efficiency was caused by the formation of raftlike domains that clustered the dye molecules into concentrated regions. On the basis of this information, we were able to design new nanocapsules using ternary mixtures of lipid and cholesterol that promoted the formation of raft domains and dye clustering. These nanocapsules showed improved photolysis efficiency over the best results we obtained previously.

  8. Encapsulation and controlled release of hydrophilic pesticide in shell cross-linked nanocapsules containing aqueous core.

    PubMed

    Sun, Chuxiang; Shu, Ke; Wang, Wei; Ye, Zhao; Liu, Ting; Gao, Yuxiang; Zheng, Hua; He, Guanghua; Yin, Yihua

    2014-03-10

    In this study, amphiphilic biocopolymers, synthesized by mixing azidobenzaldehyde (Az) and an aqueous solution of carboxymethyl chitosan (CMCS), which self-assemble into nanocapsules with a aqueous core (ACN) in aqueous media followed by photo-cross-linking to obtain shell cross-linked nanocapsules, were used to develop a controlled release pesticide system. The system was characterized by TEM and DLS. Its encapsulation efficiency was determined. The obtained result showed that it is efficient to encapsulate methomyl reaching encapsulation efficiency as high as 90% in an aqueous medium at pH 4.0, which is mainly attributed to the hydrogen bonding adsorption between methomyl molecules and the inner surface of nanocapsules. Release profiles of methomyl from methomyl-loaded nanocapsules in an aqueous solution at pH 6.0 were shown to be diffusion controlled with a half-release time (t(½)) of 36.3-69.5h from different samples. The shell cross-linking and its degree of cross-linking are assumed to be responsible for this diffusion behavior. The insecticidal activity test in laboratory showed that the control efficacy of methomyl-loaded nanocapsules against the armyworm larvae was significantly superior to the original. The relative control efficacy still maintained 100% over 7 days.

  9. Anticancer studies of drug encapsulated polyethylene terephthalate-Co-polylactic acid nanocapsules

    PubMed Central

    Kumar, K. Sathish; Kumar, P. Senthil; Vijayalakshmi, S.

    2011-01-01

    Objectives: The purpose of this study was to investigate the anticancer activity of anticancer drugs (5-fluorouracil and 6-thioguanine) in polymeric nanocapsules in the presence and in the absence of gold and iron oxide nanoparticles toward Hep2 cancer cells. Materials and Methods: MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay was used for quantitative measurements for the anticancer cell activity. Encapsulated drug in polyethylene terephthalate-polylactic acid copolymer (PET-co-PLA) nanocapsules in the presence and absence of gold and iron oxide nanoparticles were prepared via the W/O/W emulsification solvent-evaporation method. Morphology of the nanoparticles was characterized by transmission electron microscopy and scanning electron microscopy. Conclusion: The average size of the polymeric nanocapsules, gold nanoparticles, and iron oxide nanoparticles were found to be in range of 230-260, 18 -20 nm, 5-10 nm, respectively. The findings in this study inferred that incorporated drug in polymeric nanocapsules with gold nanoparticles and iron oxide nanoparticles show better anticancer activity when compared with encapsulated drug in polymeric nanocapsules. PMID:21687360

  10. Frozen waves: experimental generation.

    PubMed

    Vieira, Tarcio A; Gesualdi, Marcos R R; Zamboni-Rached, Michel

    2012-06-01

    Frozen waves (FWs) are very interesting particular cases of nondiffracting beams whose envelopes are static and whose longitudinal intensity patterns can be chosen a priori. We present here for the first time (that we know of) the experimental generation of FWs. The experimental realization of these FWs was obtained using a holographic setup for the optical reconstruction of computer generated holograms (CGH), based on a 4-f Fourier filtering system and a nematic liquid crystal spatial light modulator (LC-SLM), where FW CGHs were first computationally implemented, and later electronically implemented, on the LC-SLM for optical reconstruction. The experimental results are in agreement with the corresponding theoretical analytical solutions and hold excellent prospects for implementation in scientific and technological applications.

  11. Multifunctional Nanocapsules for Simultaneous Encapsulation of Hydrophilic and Hydrophobic Compounds and On-Demand Release

    PubMed Central

    Hu, Shang-Hsiu; Chen, San-Yuan; Gao, Xiaohu

    2012-01-01

    Cocktail therapy by delivering multiple drugs to diseased cells can elicit synergistic therapeutic effects and better modulate the complex cell signaling network. Besides selection of drug combinations, a difficulty in delivery is how to encapsulate drugs with various solubility into a common vehicle, particularly when both hydrophobic and hydrophilic compounds are involved. Furthermore, it is highly desirable that the drug release profile can be controlled in an on-demand fashion for balanced therapeutic and side effects. Based on a simple and scalable double-emulsion approach, we report a new class of nanocapsules that can solve these problems simultaneously. Further linking the nanocapsules with peptides targeting cell surface integrins leads to significantly enhanced cell uptake of the nanocapsules. Intracellular drug release triggered by external stimuli has also been achieved without affecting cell viability. Further development of this technology should open exciting opportunities in treating tough diseases such as cancer, cardiovascular diseases, neurological disorders, and infectious diseases. PMID:22339040

  12. Structure and magnetic properties of surface alloyed Fe nanocapsules prepared by arc discharge

    NASA Astrophysics Data System (ADS)

    Si, P. Z.; Choi, C. J.; Brück, E.; Geng, D. Y.; Zhang, Z. D.

    2005-12-01

    C-Fe-Si alloy encapsulating Fe nanocapsules were fabricated by arc evaporating the mixture of Fe and SiC powders. The high temperature of the electric arc results in a surface reaction between SiC and Fe nanoparticles and therefore a uniform encapsulation of the Fe nanoparticles with its alloy. The size of the nanocapsules ranges from 10 to 60 nm while most shells are approximately 7 nm in thickness. Air oxidation to the as-prepared sample does not change the shell/core structure but the saturation magnetization and the coercivity are reduced. The characteristics of the nanocapsules were investigated systematically by using X-ray diffraction, transmission electron microscopy, energy dispersive spectra, X-ray photoelectron spectroscopy, and superconducting quantum interference device magnetometer.

  13. Preparation of highly dispersed core/shell-type titania nanocapsules containing a single Ag nanoparticle.

    PubMed

    Sakai, Hideki; Kanda, Takashi; Shibata, Hirobumi; Ohkubo, Takahiro; Abe, Masahiko

    2006-04-19

    Core/shell-type titania nanocapsules containing a single Ag nanoparticle were prepared. Ag nanoparticles were prepared using the reduction of silver nitrate with hydrazine in the presence of cetyltrimethylammonium bromide (CTAB) as protective agent. The sol-gel reaction of titanium tetraisopropoxide (TTIP) was used to prepare core/shell-type titania nanocapsules with CTAB-coated Ag nanoparticles as the core. TEM observations revealed that the size of the core (Ag particle) and the thickness of the shell (titania) of the core/shell particles obtained are about 10 nm and 5-10 nm, respectively. In addition, the nanocapsules were found to be dispersed in the medium as individual particles without aggregation. Moreover, titania coating caused the surface plasmon absorption of Ag nanoparticles to shift toward the longer wavelength side.

  14. Evaluation of the side effects of poly(epsilon-caprolactone) nanocapsules containing atrazine toward maize plants

    PubMed Central

    Oliveira, Halley C.; Stolf-Moreira, Renata; Martinez, Cláudia B. R.; Sousa, Gustavo F. M.; Grillo, Renato; de Jesus, Marcelo B.; Fraceto, Leonardo F.

    2015-01-01

    Poly(epsilon-caprolactone) (PCL) nanocapsules have been used as a carrier system for the herbicide atrazine, which is commonly applied to maize. We demonstrated previously that these atrazine containing polymeric nanocapsules were 10-fold more effective in the control of mustard plants (a target species), as compared to a commercial atrazine formulation. Since atrazine can have adverse effects on non-target crops, here we analyzed the effect of encapsulated atrazine on growth, physiological and oxidative stress parameters of soil-grown maize plants (Zea mays L.). One day after the post-emergence treatment with PCL nanocapsules containing atrazine (1 mg mL−1), maize plants presented 15 and 21% decreases in maximum quantum yield of photosystem II (PSII) and in net CO2 assimilation rate, respectively, as compared to water-sprayed plants. The same treatment led to a 1.8-fold increase in leaf lipid peroxidation in comparison with control plants. However, all of these parameters were unaffected 4 and 8 days after the application of encapsulated atrazine. These results suggested that the negative effects of atrazine were transient, probably due to the ability of maize plants to detoxify the herbicide. When encapsulated atrazine was applied at a 10-fold lower concentration (0.1 mg mL−1), a dosage that is still effective for weed control, no effects were detected even shortly after application. Regardless of the herbicide concentration, neither pre- nor post-emergence treatment with the PCL nanocapsules carrying atrazine resulted in the development of any macroscopic symptoms in maize leaves, and there were no impacts on shoot growth. Additionally, no effects were observed when plants were sprayed with PCL nanocapsules without atrazine. Overall, these results suggested that the use of PCL nanocapsules containing atrazine did not lead to persistent side effects in maize plants, and that the technique could offer a safe tool for weed control without affecting crop growth

  15. Evaluation of the side effects of poly(epsilon-caprolactone) nanocapsules containing atrazine towards maize plants

    NASA Astrophysics Data System (ADS)

    Oliveira, Halley; Stolf-Moreira, Renata; Martinez, Cláudia; Sousa, Gustavo; Grillo, Renato; de Jesus, Marcelo; Fraceto, Leonardo

    2015-10-01

    Poly(epsilon-caprolactone) (PCL) nanocapsules have been used as a carrier system for the herbicide atrazine, which is commonly applied to maize. We demonstrated previously that these atrazine containing polymeric nanocapsules were ten-fold more effective in the control of mustard plants (a target species), as compared to a commercial atrazine formulation. Since atrazine can have adverse effects on non-target crops, here we analyzed the effect of encapsulated atrazine on growth, physiological and oxidative stress parameters of soil-grown maize plants (Zea mays L.). One day after the post-emergence treatment with PCL nanocapsules containing atrazine (1 mg mL-1), maize plants presented 15 and 21 % decreases in maximum quantum yield of photosystem II and in net CO2 assimilation rate, respectively, as compared to water-sprayed plants. The same treatment led to a 1.8-fold increase in leaf lipid peroxidation in comparison with control plants. However, all of these parameters were unaffected four and eight days after the application of encapsulated atrazine. These results suggested that the negative effects of atrazine were transient, probably due to the ability of maize plants to detoxify the herbicide. When encapsulated atrazine was applied at a ten-fold lower concentration (0.1 mg mL-1), a dosage that is still effective for weed control, no effects were detected even shortly after application. Regardless of the herbicide concentration, neither pre- nor post-emergence treatment with the PCL nanocapsules carrying atrazine resulted in the development of any macroscopic symptoms in maize leaves, and there were no impacts on shoot growth. Additionally, no effects were observed when plants were sprayed with PCL nanocapsules without atrazine. Overall, these results suggested that the use of PCL nanocapsules containing atrazine did not lead to persistent side effects in maize plants, and that the technique could offer a safe tool for weed control without affecting crop growth.

  16. Magnetically Vectored Nanocapsules for Tumor Penetration and Remotely Switchable On-Demand Drug Release

    NASA Astrophysics Data System (ADS)

    Kong, Seong Deok

    Hollow-sphere nanocapsules containing intentionally trapped magnetic nanoparticles and defined anticancer drugs provide a powerful magnetic vector under moderate gradient magnetic fields, and enable the nanocapsules to penetrate into the midst of tumors and allow a controlled on-off switchable release of the anticancer drug cargo by remotely applied Radio Frequency (RF) magnetic field. This imageable smart drug delivery system is compact because the drug molecules and magnetic nanoparticles can all be self-contained within 80~150 nm capsules. In vitro as well as in vivo results indicate that the nanocapsules are effective in reducing tumor cell growth. In Chapter 1, the concept of Drug Delivery Systems (DDSs) and the impact of nanotechnology on Drug Delivery Systems were introduced. Triggered drug release using magnetothermally-responsive nanomaterials, magnetic nanoparticles for nanomedicine, and ordered mesoporous materials in the context of Drug Delivery System were discussed. In Chapter 2, creation of remotely controllable, On-Off switchable drug release methodology was described. In this thesis work, triggerable nanocapsules which contain magnetic nanoparticles responsive to external radio frequency (RF) magnetic field have been successfully created. This is in contrast to the regular hollow nanospheres for slow passive release of drugs. The new nanocapsule material consists of bio-inert, bio-compatible or bio-degradable material that we can be selected from a variety of materials depending on specific medical applications. In Chapter 3, study and utilization of magnetic vector for guided tumor penetration was discussed. In the presence of a moderate gradient magnetic field, a powerful magnetic vector is created that allows these nanocapsules to cross cell membranes or blood-tissue barriers and penetrate into the midst of tumors, thus overcoming the well-known problem of limited access of anti-cancer drugs to cancer cells in the interior of a tumor tissue. In

  17. Synthesis of Polydopamine-Like Nanocapsules via Removal of a Sacrificial Mesoporous Silica Template with Water.

    PubMed

    Nador, Fabiana; Guisasola, Eduardo; Baeza, Alejandro; Villaecija, Miguel Angel Moreno; Vallet-Regí, Maria; Ruiz-Molina, Daniel

    2017-02-24

    Hollow polymeric polydopamine (PDA) micro-/nanocapsules have been obtained through a very simple, mild, and straightforward method that involves coating of silica mesoporous nanoparticles through an ammonia-triggered polymerization of PDA and the posterior removal of the sacrificial template simply by dispersion in water, without the need of any harsh chemical reagent, either in the presence or absence of active principles, from doxorubicin to iron oxide nanoparticles. To demonstrate the potential of the nanocapsules obtained with this new approach, they have been successfully used as nanocarriers for drug delivery.

  18. Liposome-like nanocapsules of dual drug-tailed betaine for cancer therapy.

    PubMed

    Fang, Shuo; Niu, Yuge; Zhang, Wei; Zhang, Yemin; Yu, Liangli; Zhang, Yingyi; Li, Xinsong

    2015-09-30

    A novel dual drug-tailed betaine conjugate amphiphile has been firstly synthesized in which the polar headgroup is derived from glycine betaine and the hydrophobic tails are chlorambucil molecules. The newly prepared conjugate undergoes self-assembly to form stable liposome-like nanocapsules as an effective carrier with high drug loading capacity. The nanocapsules showed higher cytotoxic effects to cancer cell lines than those of free chlorambucil in vitro, and inhibited tumor growth effectively in vivo. This strategy that utilizes new dual drug-tailed betaine conjugate amphiphile to construct a self-assembled nanoparticle drug delivery system may have great potential in cancer chemotherapy.

  19. The equine frozen semen industry.

    PubMed

    Loomis, P R

    2001-12-03

    Recent acceptance of frozen semen as a method to produce registered foals by two of the worlds largest breed associations, the American Quarter Horse and American Paint Horse, has stimulated new interest in frozen semen technology. This review will: (a) attempt to identify the major impediments to the development of the frozen semen industry, (b) suggest alternative methods for marketing and application of frozen semen, and (c) present the results of a recent study in our laboratory. The objective of which was to compare pregnancy rates of insemination with cooled and frozen semen. Major impediments to the development of the frozen semen industry include 1. Lower fertility with frozen semen as compared to cooled semen for many stallions. 2. Increased costs associated with management of mares for AI with frozen semen using current insemination protocols. 3. Unfavorable marketing practices for frozen semen. Reports of fertility with cooled transported semen in commercial breeding programs indicate seasonal pregnancy rates ranging from 60 to 90%. We compiled data from three commercial transported cooled semen programs in which semen from 16 stallions was used for insemination of 850 mares throughout North America by local veterinarians. During the 1999 and 2000 breeding seasons, first cycle and seasonal pregnancy rates of 59.4 and 74.7% were obtained. During that same period, first cycle and seasonal pregnancy rates of 51.3 and 75.6% were obtained following insemination of 876 mares with frozen semen from 106 different stallions processed by our laboratory and distributed through our commercial distribution program. First cycle and seasonal pregnancy rates were higher for mares bred outside of North America than for mares bred within North America (53.5 and 81.9 versus 49.4 and 65.6%, respectively). Seasonal pregnancy rates were higher presumably because of the better mare management employed for mares bred with exported semen and the fact that some of the domestic

  20. ULTRATHIN FROZEN SECTIONS

    PubMed Central

    Leduc, Elizabeth H.; Bernhard, W.; Holt, S. J.; Tranzer, J. P.

    1967-01-01

    Endogenous enzyme activity can be readily and routinely demonstrated in ultrathin, frozen sections for electron microscopy. The procedure employed to obtain the best structural preservation as well as enzyme activity in thin sections involved fixation in glutaraldehyde, embedding in thiolated gelatin or pure gelatin, partial dehydration in glycerol, and sectioning in a cryostat at -35°C with a slightly modified Porter-Blum microtome on which the tissue is maintained at -70°C and the knife at -23°C. Kidney cortex was used as test tissue, but a few other organs were occasionally used. Thin sections were floated on the surface of several incubation media routinely employed for enzyme cytochemistry. Positive, specific reactions were obtained for alkaline phosphatase in kidney brush border, for adenosine triphosphatase in brush border and in basal membranes of distal tubules, for acid phosphatase and esterase in lysosomes, and for NADH diaphorase in mitochondria. Mitochondrial ATPase was sporadically evident only in the distal tubule of the kidney. Localizations of enzyme activity reported by other technical approaches were confirmed and in some cases somewhat improved. PMID:4293006

  1. Effects of Two Types of Melatonin-Loaded Nanocapsules with Distinct Supramolecular Structures: Polymeric (NC) and Lipid-Core Nanocapsules (LNC) on Bovine Embryo Culture Model.

    PubMed

    Komninou, Eliza Rossi; Remião, Mariana Härter; Lucas, Caroline Gomes; Domingues, William Borges; Basso, Andrea Cristina; Jornada, Denise Soledade; Deschamps, João Carlos; Beck, Ruy Carlos Ruver; Pohlmann, Adriana Raffin; Bordignon, Vilceu; Seixas, Fabiana Kömmling; Campos, Vinicius Farias; Guterres, Silvia Stanisçuaski; Collares, Tiago

    2016-01-01

    Melatonin has been used as a supplement in culture medium to improve the efficiency of in vitro produced mammalian embryos. Through its ability to scavenge toxic oxygen derivatives and regulate cellular mRNA levels for antioxidant enzymes, this molecule has been shown to play a protective role against damage by free radicals, to which in vitro cultured embryos are exposed during early development. In vivo and in vitro studies have been performed showing that the use of nanocapsules as active substances carriers increases stability, bioavailability and biodistribution of drugs, such as melatonin, to the cells and tissues, improving their antioxidant properties. These properties can be modulated through the manipulation of formula composition, especially in relation to the supramolecular structures of the nanocapsule core and the surface area that greatly influences drug release mechanisms in biological environments. This study aimed to evaluate the effects of two types of melatonin-loaded nanocapsules with distinct supramolecular structures, polymeric (NC) and lipid-core (LNC) nanocapsules, on in vitro cultured bovine embryos. Embryonic development, apoptosis, reactive oxygen species (ROS) production, and mRNA levels of genes involved in cell apoptosis, ROS and cell pluripotency were evaluated after supplementation of culture medium with non-encapsulated melatonin (Mel), melatonin-loaded polymeric nanocapsules (Mel-NC) and melatonin-loaded lipid-core nanocapsules (Mel-LNC) at 10-6, 10-9, and 10-12 M drug concentrations. The highest hatching rate was observed in embryos treated with 10-9 M Mel-LNC. When compared to Mel and Mel-NC treatments at the same concentration (10-9 M), Mel-LNC increased embryo cell number, decreased cell apoptosis and ROS levels, down-regulated mRNA levels of BAX, CASP3, and SHC1 genes, and up-regulated mRNA levels of CAT and SOD2 genes. These findings indicate that nanoencapsulation with LNC increases the protective effects of melatonin

  2. Effects of Two Types of Melatonin-Loaded Nanocapsules with Distinct Supramolecular Structures: Polymeric (NC) and Lipid-Core Nanocapsules (LNC) on Bovine Embryo Culture Model

    PubMed Central

    Komninou, Eliza Rossi; Remião, Mariana Härter; Lucas, Caroline Gomes; Domingues, William Borges; Basso, Andrea Cristina; Jornada, Denise Soledade; Deschamps, João Carlos; Beck, Ruy Carlos Ruver; Pohlmann, Adriana Raffin; Bordignon, Vilceu; Seixas, Fabiana Kömmling; Campos, Vinicius Farias; Guterres, Silvia Stanisçuaski; Collares, Tiago

    2016-01-01

    Melatonin has been used as a supplement in culture medium to improve the efficiency of in vitro produced mammalian embryos. Through its ability to scavenge toxic oxygen derivatives and regulate cellular mRNA levels for antioxidant enzymes, this molecule has been shown to play a protective role against damage by free radicals, to which in vitro cultured embryos are exposed during early development. In vivo and in vitro studies have been performed showing that the use of nanocapsules as active substances carriers increases stability, bioavailability and biodistribution of drugs, such as melatonin, to the cells and tissues, improving their antioxidant properties. These properties can be modulated through the manipulation of formula composition, especially in relation to the supramolecular structures of the nanocapsule core and the surface area that greatly influences drug release mechanisms in biological environments. This study aimed to evaluate the effects of two types of melatonin-loaded nanocapsules with distinct supramolecular structures, polymeric (NC) and lipid-core (LNC) nanocapsules, on in vitro cultured bovine embryos. Embryonic development, apoptosis, reactive oxygen species (ROS) production, and mRNA levels of genes involved in cell apoptosis, ROS and cell pluripotency were evaluated after supplementation of culture medium with non-encapsulated melatonin (Mel), melatonin-loaded polymeric nanocapsules (Mel-NC) and melatonin-loaded lipid-core nanocapsules (Mel-LNC) at 10−6, 10−9, and 10−12 M drug concentrations. The highest hatching rate was observed in embryos treated with 10−9 M Mel-LNC. When compared to Mel and Mel-NC treatments at the same concentration (10−9 M), Mel-LNC increased embryo cell number, decreased cell apoptosis and ROS levels, down-regulated mRNA levels of BAX, CASP3, and SHC1 genes, and up-regulated mRNA levels of CAT and SOD2 genes. These findings indicate that nanoencapsulation with LNC increases the protective effects of

  3. Hydrogels containing redispersible spray-dried melatonin-loaded nanocapsules: a formulation for transdermal-controlled delivery

    NASA Astrophysics Data System (ADS)

    Hoffmeister, Cristiane RD; Durli, Taís L.; Schaffazick, Scheila R.; Raffin, Renata P.; Bender, Eduardo A.; Beck, Ruy CR; Pohlmann, Adriana R.; Guterres, Sílvia S.

    2012-05-01

    The aim of the present study was to develop a transdermal system for controlled delivery of melatonin combining three strategies: nanoencapsulation of melatonin, drying of melatonin-loaded nanocapsules, and incorporation of nanocapsules in a hydrophilic gel. Nanocapsules were prepared by interfacial deposition of the polymer and were spray-dried using water-soluble excipients. In vitro drug release profiles were evaluated by the dialysis bag method, and skin permeation studies were carried out using Franz cells with porcine skin as the membrane. The use of 10% ( w/ v) water-soluble excipients (lactose or maltodextrin) as spray-drying adjuvants furnished redispersible powders (redispersibility index approximately 1.0) suitable for incorporation into hydrogels. All formulations showed a better controlled in vitro release of melatonin compared with the melatonin solution. The best controlled release results were achieved with hydrogels prepared with dried nanocapsules (hydrogels > redispersed dried nanocapsules > nanocapsule suspension > melatonin solution). The skin permeation studies demonstrated a significant modulation of the transdermal melatonin permeation for hydrogels prepared with redispersible nanocapsules. In this way, the additive effect of the different approaches used in this study (nanoencapsulation, spray-drying, and preparation of semisolid dosage forms) allows not only the control of melatonin release, but also transdermal permeation.

  4. Core/shell-structured nickel/nitrogen-doped onion-like carbon nanocapsules with improved electromagnetic wave absorption properties

    NASA Astrophysics Data System (ADS)

    Wu, Niandu; Liu, Xianguo; Or, Siu Wing

    2016-05-01

    Core/shell-structured nickel/nitrogen-doped onion-like carbon (Ni/(C, N)) nanocapsules are synthesized by a modified arc-discharge method using N2 gas as the source of N atoms. Core/shell-structured Ni/C nanocapsules are also prepared for comparison. The Ni/(C, N) nanocapsules with diameters of 10-80 nm exhibit a clear core/shell structure. The doping of N atoms introduces more lattice defects into the (C, N) shells and creates more disorderly C in the (C, N) shells. This leads to a slight shift in the dielectric resonance peak to the lower frequency side and an increase in the dielectric loss tangent for the Ni/(C, N) nanocapsules in comparison with the Ni/C nanocapsules. The magnetic permeability of both types of nanocapsules remains almost unaltered since the N atoms exist only in the (C, N) shells. The reflection loss (RL) of the Ni/(C, N) nanocapsules not only reaches a high value of -35 dB at 13.6 GHz, but also is generally improved in the low-frequency S and C microwave bands covering 2-8 GHz as a result of the N-doping-induced additional dipolar polarization and dielectric loss from the (C, N) shells.

  5. Engineering of vault nanocapsules with enzymatic and fluorescent properties.

    PubMed

    Kickhoefer, Valerie A; Garcia, Yvette; Mikyas, Yeshi; Johansson, Erik; Zhou, Jing C; Raval-Fernandes, Sujna; Minoofar, Payam; Zink, Jeffrey I; Dunn, Bruce; Stewart, Phoebe L; Rome, Leonard H

    2005-03-22

    One of the central issues facing the emerging field of nanotechnology is cellular compatibility. Nanoparticles have been proposed for diagnostic and therapeutic applications, including drug delivery, gene therapy, biological sensors, and controlled catalysis. Viruses, liposomes, peptides, and synthetic and natural polymers have been engineered for these applications, yet significant limitations continue to prevent their use. Avoidance of the body's natural immune system, lack of targeting specificity, and the inability to control packaging and release are remaining obstacles. We have explored the use of a naturally occurring cellular nanoparticle known as the vault, which is named for its morphology with multiple arches reminiscent of cathedral ceilings. Vaults are 13-MDa ribonucleoprotein particles with an internal cavity large enough to sequester hundreds of proteins. Here, we report a strategy to target and sequester biologically active materials within the vault cavity. Attachment of a vault-targeting peptide to two proteins, luciferase and a variant of GFP, resulted in their sequestration within the vault cavity. The targeted proteins confer enzymatic and fluorescent properties on the recombinant vaults, both of which can be detected by their emission of light. The modified vaults are compatible with living cells. The ability to engineer vault particles with designed properties and functionalities represents an important step toward development of a biocompatible nanocapsule.

  6. Hybrid Collagenase Nanocapsules for Enhanced Nanocarrier Penetration in Tumoral Tissues.

    PubMed

    Villegas, María Rocío; Baeza, Alejandro; Vallet-Regí, María

    2015-11-04

    Poor penetration of drug delivery nanocarriers within dense extracellular matrices constitutes one of the main liabilities of current nanomedicines. The conjugation of proteolytic enzymes on the nanoparticle surface constitutes an attractive alternative. However, the scarce resistance of these enzymes against the action of proteases or other aggressive agents present in the bloodstream strongly limits their application. Herein, a novel nanodevice able to transport proteolytic enzymes coated with an engineered pH-responsive polymeric is presented. This degradable coat protects the housed enzymes against proteolytic attack at the same time that it triggers their release under mild acidic conditions, usually present in many tumoral tissues. These enzyme nanocapsules have been attached on the surface of mesoporous silica nanoparticles, as nanocarrier model, showing a significatively higher penetration of the nanoparticles within 3D collagen matrices which housed human osteosarcoma cells (HOS). This strategy can improve the therapeutic efficacy of the current nanomedicines, allowing a more homogeneous and deeper distribution of the therapeutic nanosystems in cancerous tissues.

  7. Eugenol nanocapsule for enhanced therapeutic activity against periodontal infections.

    PubMed

    Pramod, Kannissery; Aji Alex, M R; Singh, Manisha; Dang, Shweta; Ansari, Shahid H; Ali, Javed

    2016-01-01

    Eugenol is a godsend to dental care due to its analgesic, local anesthetic, and anti-inflammatory and antibacterial effects. The aim of the present research work was to prepare, characterize and evaluate eugenol-loaded nanocapsules (NCs) against periodontal infections. Eugenol-loaded polycaprolactone (PCL) NCs were prepared by solvent displacement method. The nanometric size of the prepared NCs was confirmed by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The in vitro drug release was found to follow a biphasic pattern and followed Michaelis-Menten like model. The percentage cell viability values near to 100 in the cell viability assay indicated that the NCs are not cytotoxic. In the in vivo studies, the eugenol NC group displayed significant difference in the continuity of epithelium of the interdental papilla in comparison to the untreated, pure eugenol and placebo groups. The in vivo performance of the eugenol-loaded NCs using ligature-induced periodontitis model in rats indicated that eugenol-loaded NCs could prevent septal bone resorption in periodontitis. On the basis of our research findings it could be concluded that eugenol-loaded PCL NCs could serve as a novel colloidal drug delivery system for enhanced therapeutic activity of eugenol in the treatment of periodontal infections.

  8. CPMV-induced synthesis of hollow mesoporous SiO2 nanocapsules with excellent performance in drug delivery.

    PubMed

    Kumar, Koushi; Kumar Doddi, Shanmukha; Arunasree, Marasanapalli Kalle; Paik, Pradip

    2015-03-07

    Hollow mesoporous-SiO2 nanocapsules have been synthesized at room temperature using unmodified cowpea Mosaic Virus (CPMV) as a template, and without using any catalyst or surfactant during the synthesis. The average size of the capsules synthesized was ∼200-250 nm with a 60-100 nm hollow core. The resulting nanocapsules were characterized using high resolution transmission electron microscopy (HRTEM). The biocompatibility of the hollow mesoporous SiO2 nanocapsules was investigated with an MTT assay using the RAW 264.7 cells, HepG2 cells (human liver carcinoma cells), and Hek293 cells (human embryonic kidney cells). The nanocapsules were loaded with fluorescent molecules (rhodamine 6G), doxorubicin (DOX) – an anticancer drug, and chloroquine diphosphate (CQDP) – an antimalarial drug, and their release was studied using a UV-Vis spectrometer. The development of surfactant free, bio-safe, hollow and mesoporous SiO2 nanocapsules with CPMV provides a route for the synthesis of porous nanocapsules for drug loading and the sustained delivery of drugs. The synthesis method for hollow mesoporous SiO2 nanocapsules using CPMV is novel, straightforward, and further demonstrates that, in general, nanoformulated capsules can be used for various drug-delivery-based therapeutic applications. To check the in vitro efficacy in medical biotechnology, Hek293 and HepG2 cell lines were used to study the cell viability of DOX-loaded hollow silica nanocapsules. The results show that the bio SiO2 nanocapsules synthesized with CPMV present an effective cargo and are suitable for nanoformulating with DOX, with the resultant nanoformulation showing good promise for killing cancer specific cells.

  9. Manageable cytotoxicity of nanocapsules immobilizing D-amino acid oxidase via exogenous administration of nontoxic prodrug

    NASA Astrophysics Data System (ADS)

    Zhao, Yang; Zhu, Yingchun; Fu, Jingke

    2014-02-01

    D-Amino acid oxidase (DAO), which could catalyze generation of hydrogen peroxide with strong oxidbility and cytotoxicity, has become of interest as a biocatalyst for therapeutic treatments. Herein we report that amino-functional hollow mesoporous silica with large pore size (10.27 nm) and positively charged surface effectively immobilize DAO with negative charge. The adsorption, activity and stability of DAO are demonstrated to depend mainly on the amino-functionalization of surface. Significant cancer cell killing effect is observed when the cells are treated by the nanocapsules entrapping DAO together with D-alanine, showing distinct dose-dependency on concentration of the nanocapsules entrapping DAO or D-alanine. Nevertheless, the toxicity is completely neutralized by the addition of catalase, and anti-tumor effect is not observed when either the nanocapsules entrapping DAO or D-alanine is applied alone. The results indicate that cytotoxicity of the nanocapsules entrapping DAO could be managed by exogenous administration of nontoxic prodrug to tumor tissue, due to the stereoselectivity of DAO and the scarcity of its substrates in mammalian organisms. Thus, the method might be exploited as a potential treatment for cancer therapy.

  10. PVM/MA-shelled selol nanocapsules promote cell cycle arrest in A549 lung adenocarcinoma cells

    PubMed Central

    2014-01-01

    Background Selol is an oily mixture of selenitetriacylglycerides that was obtained as a semi-synthetic compound containing selenite. Selol is effective against cancerous cells and less toxic to normal cells compared with inorganic forms of selenite. However, Selol’s hydrophobicity hinders its administration in vivo. Therefore, the present study aimed to produce a formulation of Selol nanocapsules (SPN) and to test its effectiveness against pulmonary adenocarcinoma cells (A549). Results Nanocapsules were produced through an interfacial nanoprecipitation method. The polymer shell was composed of poly(methyl vinyl ether-co-maleic anhydride) (PVM/MA) copolymer. The obtained nanocapsules were monodisperse and stable. Both free Selol (S) and SPN reduced the viability of A549 cells, whereas S induced a greater reduction in non-tumor cell viability than SPN. The suppressor effect of SPN was primarily associated to the G2/M arrest of the cell cycle, as was corroborated by the down-regulations of the CCNB1 and CDC25C genes. Apoptosis and necrosis were induced by Selol in a discrete percentage of A549 cells. SPN also increased the production of reactive oxygen species, leading to oxidative cellular damage and to the overexpression of the GPX1, CYP1A1, BAX and BCL2 genes. Conclusions This study presents a stable formulation of PVM/MA-shelled Selol nanocapsules and provides the first demonstration that Selol promotes G2/M arrest in cancerous cells. PMID:25149827

  11. Cotton fabric functionalisation with menthol/PCL micro- and nano-capsules for comfort improvement.

    PubMed

    Mossotti, Raffaella; Ferri, Ada; Innocenti, Riccardo; Zelenková, Tereza; Dotti, Francesca; Marchisio, Daniele L; Barresi, Antonello A

    2015-01-01

    Cotton functionalisation with poly-ɛ-caprolactone (PCL) micro- and nano-capsules containing menthol was carried out with the aim of introducing a long-lasting refreshing sensation. The preparation of the polymer micro- and nano-capsules was carried out by solvent displacement technique. A confined impinging jets mixer was used in order to ensure fast mixing and generate a homogeneous environment where PCL and menthol can self-assemble. The micro- and nano-capsules and the functionalised fabrics were characterised by means of DSC, FT-IR spectroscopy and SEM imaging. Micro- and nano-capsules of different size, from about 200 to about 1200 nm, were obtained varying menthol to PCL ratio (from 0.76 to 8), overall concentration and flow rate (i.e. mixing conditions). The inclusion of menthol was confirmed by DSC analysis. A patch test was carried out by 10 volunteers. Micro-capsules were found to be effective in conferring the fabric a refreshing sensation without altering skin physiology.

  12. Modulation of Gene Expression by Polymer Nanocapsule Delivery of DNA Cassettes Encoding Small RNAs.

    PubMed

    Yan, Ming; Wen, Jing; Liang, Min; Lu, Yunfeng; Kamata, Masakazu; Chen, Irvin S Y

    2015-01-01

    Small RNAs, including siRNAs, gRNAs and miRNAs, modulate gene expression and serve as potential therapies for human diseases. Delivery to target cells remains the fundamental limitation for use of these RNAs in humans. To address this challenge, we have developed a nanocapsule delivery technology that encapsulates small DNA molecules encoding RNAs into a small (30 nm) polymer nanocapsule. For proof of concept, we transduced DNA expression cassettes for three small RNAs. In one application, the DNA cassette encodes an shRNA transcriptional unit that downregulates CCR5 and protects from HIV-1 infection. The DNA cassette nanocapsules were further engineered for timed release of the DNA cargo for prolonged knockdown of CCR5. Secondly, the nanocapsules provide an efficient means for delivery of gRNAs in the CRISPR/Cas9 system to mutate integrated HIV-1. Finally, delivery of microRNA-125b to mobilized human CD34+ cells enhances survival and expansion of the CD34+ cells in culture.

  13. Glutathione Responsive Hyaluronic Acid Nanocapsules Obtained by Bioorthogonal Interfacial "Click" Reaction.

    PubMed

    Baier, Grit; Fichter, Michael; Kreyes, Andreas; Klein, Katja; Mailänder, Volker; Gehring, Stephan; Landfester, Katharina

    2016-01-11

    Azide-functionalized hyaluronic acid and disulfide dialkyne have been used for "click" reaction polymerization at the miniemulsion droplets interface leading to glutathione responsive nanocapsules (NCs). Inverse miniemulsion polymerization was chosen, due to its excellent performance properties, for example, tuning of size and size distribution, shell thickness/density, and high pay loading efficiency. The obtained size, size distribution, and encapsulation efficiency were checked via fluorescent spectroscopy, and the tripeptide glutathione was used to release an encapsulated fluorescent dye after cleavage of the nanocapsules shell. To show the glutathione-mediated intracellular cleavage of disulfide-containing NC shells, CellTracker was encapsulated into the nanocapsules. The cellular uptake in dendritic cells and the cleavage of the nanocapsules in the cells were studied using confocal laser scanning microscopy. Because of the mild reaction conditions used during the interfacial polymerization and the excellent cleavage properties, we believe that the synthesis of glutathione responsive hyaluronic acid NCs reported herein are of high interest for the encapsulation and release of sensitive compounds at high yields.

  14. In vitro evaluation of α-lipoic acid-loaded lipid nanocapsules for topical delivery.

    PubMed

    Xia, Nan; Liu, Tian; Wang, Qiang; Xia, Qiang; Bian, Xiaoli

    2017-09-03

    This study aimed at in vitro evaluation of α-lipoic acid-loaded lipid nanocapsules for topical delivery, which was prepared by hot high-pressure homogenisation. Stable particles could be formed and particle size was 148.54 ± 2.31 nm with polydispersity index below 0.15. Encapsulation efficiency and drug loading of α-lipoic acid were 95.23 ± 0.45% and 2.81 ± 0.37%. Antioxidant study showed α-lipoic acid could be protected by lipid nanocapsules without loss of antioxidant activity. Sustained release of α-lipoic acid from lipid nanocapsules was obtained and cumulative release was 62.18 ± 1.51%. In vitro percutaneous study showed the amount of α-lipoic acid distributed in skin was 1.7-fold than permeated. Cytotoxicity assay and antioxidant activity on L929 cells indicated this formulation had low cytotoxicity and ability of protecting cells from oxidative damage within specific concentration. These studies suggested α-lipoic acid-loaded lipid nanocapsules could be potential formulation for topical delivery.

  15. Chitosan gel containing polymeric nanocapsules: a new formulation for vaginal drug delivery

    PubMed Central

    Frank, Luiza A; Sandri, Giuseppina; D’Autilia, Francesca; Contri, Renata V; Bonferoni, Maria Cristina; Caramella, Carla; Frank, Alejandro G; Pohlmann, Adriana R; Guterres, Silvia S

    2014-01-01

    The vaginal route of administration is an alternative for several treatments for either local or systemic pharmacological effects. However, the permanence of a drug in this route represents a challenge for formulation development that can be overcome by using nanoencapsulation and chitosan gel. Thus, this work aimed to evaluate the performance of chitosan hydrogels containing cationic and anionic acrylic-based nanocapsules (Eudragit® RS 100 and Eudragit® S 100, respectively) with Nile red as a model of lipophilic substance in the vaginal route of administration, as measured by increases in the residence time and the penetration of these formulations. Several formulations were prepared with increasing chitosan concentrations, and were analyzed in terms of pH and rheological behavior so that the most suitable formulation could be selected. The enhancement of the adhesion (tensile stress test and washability profile) and penetration (confocal laser scanning microscopy and extraction followed by quantification) properties of the formulations, when applied to porcine vaginal mucosa, were evaluated. The nanocapsule suspensions produced presented adequate properties: size of approximately 200 nm (polydispersity index of ≤v0.2); zeta potential around +10 mV for the cationic formulation and -10 mV for the anionic formulation; and pH values of 6.1±0.1 (Eudragit RS 100), 5.3±0.2 (Eudragit S 100), 6.2±0.1 (Nile red loaded Eudragit RS 100), and 5.1±0.1 (Nile red loaded Eudragit S 100). The chitosan formulation presented suitable viscosity for vaginal application and acidic pH (approximately 4.5). The tensile stress test showed that both formulations containing polymeric nanocapsules presented higher mucoadhesion when compared with the formulation without nanocapsules. In the washability experiment, no significant differences were found between formulations. Confocal microscopy and fluorescence quantification after extraction from the mucosa showed higher penetration of

  16. Nanoparticles and nanocapsules created using the Ouzo effect: spontaneous emulisification as an alternative to ultrasonic and high-shear devices.

    PubMed

    François, Ganachaud; Katz, Joseph L

    2005-02-01

    The preparation of polymeric particles and capsules by means of spontaneous droplet formation and subsequent polymer precipitation or synthesis is well-known. However, spontaneous emulsification is a phenomenon that has often been erroneously interpreted. This Minireview provides new insights into the preparation of metastable liquid dispersions by homogeneous liquid-liquid nucleation, and is based primarily on a recent study by Vitale and Katz (Langmuir, 2003, 19, 4105-4110). This spontaneous emulsification, which they named the Ouzo effect, occurs upon pouring, into water, a mixture of a totally water-miscible solvent and a hydrophobic oil--and optionally some water--thus generating long-lived small droplets, which are formed even though no surfactant is present. Herein, we review and reinterpret the most relevant publications on the synthesis of a variety of dispersions (pseudolatexes, silicone emulsions, biodegradable polymeric nanocapsules, etc.), which we believe have actually been synthesized using the Ouzo effect. The Ouzo effect may also become a substitute for high-shear techniques, which, to date have only been of limited utility on industrial scales.

  17. Preparation and characterization of PEGylated chitosan nanocapsules as a carrier for pharmaceutical application

    NASA Astrophysics Data System (ADS)

    Najafabadi, Alireza Hassani; Abdouss, Majid; Faghihi, Shahab

    2014-03-01

    A new method to conjugate methoxy polyethylene glycol (mPEG) to C6 position of chitosan under the mild condition is introduced that improves the biocompatibility and water solubility of chitosan. Harsh deprotecting step and several purification cycles are two major disadvantages of the current methods for preparing PEGylated chitosan. In this study, the amine groups at C2 position of chitosan are protected using SDS followed by grafting the PEG. The protecting group of chitosan is simply removed by dialyzing against Tris solution. The chemical structure of the prepared polymer is characterized by FTIR and 1H NMR spectroscopy. Fourier transformed-infrared (FT-IR) and 1H NMR spectra confirmed that the mPEG is successfully grafted to C6 position of chitosan. Prepared methoxy polyethylene glycol (mPEG) is then employed to prepare the nanocapsules for the encapsulation of poor water-soluble drug, propofol. The TEM, AFM, and DLS techniques are used to characterize the prepared nanocapsules size and morphology. The results show a size of about 80 nm with spherical shape for nanocapsules. In vitro drug release is carried out to evaluate the potential of nanocarriers for the intravenous delivery of drugs. The profile of release from formulated nanocapsules is similar to those of commercial lipid emulsion (CLE). In vivo animal sleep-recovery test on rats shows a close similarity between the time of unconsciousness and recovery of righting reflex between nanoparticles and CLE. This study provides an efficient, novel, and easy method for preparing a carrier system that requires less intensive reaction conditions, fewer reaction steps, and less purification steps. In addition, the nanocapsules introduced here could be a promising nano carrier for the delivery of poor water-soluble drugs.

  18. Chitosan nanocapsules: Effect of chitosan molecular weight and acetylation degree on electrokinetic behaviour and colloidal stability.

    PubMed

    Santander-Ortega, M J; Peula-García, J M; Goycoolea, F M; Ortega-Vinuesa, J L

    2011-02-01

    In recent years, chitosan nanocapsules have shown promising results as carriers for oral drug or peptide delivery. The success in their applicability strongly depends on the stability of these colloidal systems passing through the digestive tract. In gastric fluids, clear stability comes from the high surface charge density of the chitosan shell, which is completely charged at acidic pH values. However, in the intestinal fluid (where the pH is almost neutral) the effective charge of these nanocapsules approaches zero, and the electrostatic forces cannot provide any stabilization. Despite the lack of surface charge, chitosan nanocapsules remain stable in simulated intestinal fluids. Recently, we have demonstrated that this anomalous stability (at zero charge) is owed to short-range repulsive forces that appear between hydrophilic particles when immersed in saline media. The present work examines the influence of the chitosan hydrophobicity, as well as molecular weight, in the stability of different chitosan nanocapsules. A study has been made of the size, polydispersity, electrophoretic mobility, and colloidal stability of eight core-shell nanocapsule systems, in which the chitosan-shell properties have been modified using low-molecular-weight (LMW) and high-molecular-weight (HMW) chitosan chains having different degrees of acetylation (DA). With regard to the stability mediated by repulsive hydration forces, the LMW chitosan provided the best results. In addition, contrary to initial expectations, greater stability (also mediated by hydration forces) was found in the samples formed with chitosan chains of high DA values (i.e. with less hydrophilic chitosan). Finally, a theoretical treatment was also tested to quantify the hydrophilicity of the chitosan shells. Copyright © 2010 Elsevier B.V. All rights reserved.

  19. 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.

  20. Overcoming T. gondii infection and intracellular protein nanocapsules as biomaterials for ultrasonically controlled drug release.

    PubMed

    Aw, M S; Paniwnyk, L

    2017-09-26

    One of the pivotal matters of concern in intracellular drug delivery is the preparation of biomaterials containing drugs that are compatible with the host target. Nanocapsules for oral delivery are found to be suitable candidates for targeting Toxoplasma gondii (T. gondii), a maneuvering and smart protozoic parasite found across Europe and America that causes a subtle but deadly infection. To overcome this disease, there is much potential of integrating protein-based cells into bioinspired nanocompartments such as via biodegradable cross-linked disulfide polyelectrolyte nanoparticles. The inner membrane vesicle system of these protein-drugs is not as simple as one might think. It is a complex transport network that includes sequential pathways, namely, endocytosis, exocytosis and autophagy. Unfortunately, the intracellular trafficking routes for nanoparticles in cells have not been extensively and intensively investigated. Hence, there lies the need to create robust protein nanocapsules for precise tracing and triggering of drug release to combat this protozoic disease. Protein nanocapsules have the advantage over other biomaterials due to their biocompatibility, use of natural ingredients, non-invasiveness, patient compliance, cost and time effectiveness. They also offer low maintenance, non-toxicity to healthy cells and a strictly defined route toward intracellular elimination through controlled drug delivery within the therapeutic window. This review covers the unprecedented opportunities that exist for constructing advanced nanocapsules to meet the growing needs arising from many therapeutic fields. Their versatile use includes therapeutic ultrasound for tumor imaging, recombinant DNA, ligand and functional group binding, the delivery of drugs and peptides via protein nanocapsules and polyelectrolytes, ultrasound-(US)-aided drug release through the gastrointestinal (GI) tract, and the recent progress in targeting tumor cells and a vast range of cancer therapies

  1. A simple sonochemical method for fabricating poly(methyl methacrylate)/stearic acid phase change energy storage nanocapsules.

    PubMed

    Wang, Guxia; Xu, Weibing; Hou, Qian; Guo, Shengwei

    2015-11-01

    In this study, stearic acid suitable for thermal energy storage applications was nanoencapsulated in a poly(methyl methacrylate) shell. The nanocapsules were prepared using a simple ultrasonically initiated in situ polymerization method. The morphology and particle size of the poly(methyl methacrylate)/stearic acid phase change energy storage nanocapsules (PMS-PCESNs) were analyzed using transmission electron microscopy, scanning electron microscopy, atomic force microscopy and dynamic light scattering. The latent heat storage capacities of stearic acid and the PMS-PCESNs were determined using differential scanning calorimetry. The chemical composition of the nanocapsules was characterized using Fourier transform infrared spectroscopy. All of the results show that the PMS-PCESNs were synthesized successfully and that the latent heat storage capacity and encapsulation efficiency were 155.6 J/g and 83.0%, respectively, and the diameter of each nanocapsule was 80-90 nm.

  2. Polymeric nanocapsules with controllable crosslinking degree via combination of surface-initiated atom transfer radical polymerisation and photocrosslinking techniques.

    PubMed

    Liu, Peng; Mu, Bin; Du, Pengcheng; Hong, Zhilai

    2013-06-01

    The crosslinked polystyrene nanocapsules with controllable crosslinking degree have been prepared by the ultraviolet (UV)-induced photocrosslinking of the polystyrene grafted silica nanoparticles (SN-PS), which was obtained by the surface-initiated atom transfer radical polymerisation of styrene from the modified silica nanoparticle templates, after the silica templates were etched with hydrofluoric acid. The effect of the UV-irradiating time on the inner diameter of the nanocapsules, and the degree of crosslinking and the thickness of the shells was investigated. The dynamic light scattering results showed that the degree of crosslinking of the obtained nanocapsules increased with the prolongation of the UV-irradiation time, therefore the inner diameter of the nanocapsules increased. However, the percentage of grafting of the crosslinked polymer shells decreased with increasing the UV-irradiation time because of the photodecomposition of the polystyrene grafted during the UV-irradiated crosslinking process, according to the thermogravimetric analysis.

  3. Dry Zones Around Frozen Droplets

    NASA Astrophysics Data System (ADS)

    Bisbano, Caitlin; Nath, Saurabh; Boreyko, Jonathan; Nature-Inspired Fluids; Interfaces Team

    2015-11-01

    The saturation pressure of water vapor above supercooled water exceeds that above ice at the same temperature. A frozen droplet will therefore grow by harvesting water vapor from neighboring supercooled condensate, which has recently been demonstrated to be a primary mechanism of in-plane frost growth on hydrophobic surfaces. The underlying physics of this source-sink interaction is still poorly understood. In this work, a deposited water droplet is frozen on a dry hydrophobic surface initially held above the dew point. We demonstrate that when the surface is then cooled beneath the dew point, the frozen droplet harvests nearby water vapor in the air. This results in an annular dry zone that forms between the frozen droplet and the forming supercooled condensation. For a given ambient temperature and humidity, the length of the dry zone varied strongly with surface temperature and weakly with droplet volume. The dependence of the dry zone on surface temperature is due to the fact that the vapor pressure gradients between the ambient and the surface and between the liquid and frozen water are both functions of temperature.

  4. Dermal quercetin lipid nanocapsules: Influence of the formulation on antioxidant activity and cellular protection against hydrogen peroxide.

    PubMed

    Hatahet, T; Morille, M; Shamseddin, A; Aubert-Pouëssel, A; Devoisselle, J M; Bégu, S

    2017-02-25

    Quercetin is a plant flavonoid with strong antioxidant and antiinflammatory properties interesting for skin protection. However, its poor water solubility limits its penetration and so its efficiency on skin. For this purpose, quercetin lipid nanocapsules were formulated implementing phase inversion technique wherein several modifications were introduced to enhance quercetin loading. Quercetin lipid nanocapsules were formulated with two particle size range, (50nm and 20nm) allowing a drug loading of 18.6 and 32mM respectively. The successful encapsulation of quercetin within lipid nanocapsules increased its apparent water solubility by more than 5000 fold (from 0.5μg/ml to about 5mg/ml). The physicochemical properties of these formulations such as surface charge, stability and morphology were characterized. Lipid nanocapsules had spherical shape and were stable for 28days at 25°C. Quercetin release from lipid nanocapsules was studied and revealed a prolonged release kinetics during 24h. Using DPPH assay, we demonstrated that the formulation process of lipid nanocapsules did not modify the antioxidant activity of quercetin in vitro (92.3%). With the goal of a future dermal application, quercetin lipid nanocapsules were applied to THP-1 monocytes and proved the cellular safety of the formulation up to 2μg/ml of quercetin. Finally, formulated quercetin was as efficient as the crude form in the protection of THP-1 cells from oxidative stress by exogenous hydrogen peroxide. With its lipophilic nature and occlusive effect on skin, lipid nanocapsules present a promising strategy to deliver quercetin to skin tissue and can be of value for other poorly water soluble drug candidates.

  5. A new magnetic nanocapsule containing 5-fluorouracil: in vivo drug release, anti-tumor, and pro-apoptotic effects on CT26 cells allograft model.

    PubMed

    Shakeri-Zadeh, Ali; Shiran, Mohammad-Bagher; Khoee, Sepideh; Sharifi, Ali Mohammad; Ghaznavi, Habib; Khoei, Samideh

    2014-10-01

    The purpose of this study was to create an optimized method for preparation of 5-fluorouracil-loaded magnetic poly lactic-co-glycolic acid nanocapsules and to investigate its potential as multifunctional carriers to deliver therapeutic agents for tumor-targeted therapies. The in vitro release of the newly synthesized 5-fluorouracil-loaded poly lactic-co-glycolic acid magnetic nanocapsules was investigated in phosphate-buffered saline medium using the dialysis method. In vivo release studies of the magnetic nanocapsules were performed in rabbits. Finally, the targeting properties, anti-tumor, and pro-apoptotic effects of this new magnetic nanocapsule on CT26 cells allograft model were studied. The effective diameter of nanocapsules was 67.2 nm. In vivo release investigations showed that 5-fluorouracil has a sustained release profile, prolonged lifetime in the rabbit plasma, and increased tissue appetency when loaded into the magnetic nanocapsule. Magnetic resonance imaging confirmed that the magnetic nanocapsules were successfully targeted to the tumor. Additionally, the anti-tumor studies revealed that the targeted therapy with magnetic nanocapsules containing 5-fluorouracil effectively inhibits the growth of tumors compared with 5-fluorouracil alone (P < 0.01). The present study demonstrates that this new magnetic nanocapsule can be considered a new nanotechnology-based cancer chemotherapy agent in vivo.

  6. Microheterogeneity in frozen protein solutions.

    PubMed

    Twomey, Alan; Kurata, Kosaku; Nagare, Yutaka; Takamatsu, Hiroshi; Aksan, Alptekin

    2015-06-20

    In frozen and lyophilized systems, the biological to be stabilized (e.g. therapeutic protein, biomarker, drug-delivery vesicle) and the cryo-/lyo-protectant should be co-localized for successful stabilization. During freezing and drying, many factors cause physical separation of the biological from the cryo-/lyo-protectant, called microheterogeneity (MH), which may result in poor stabilization efficiency. We have developed a novel technique that utilized confocal Raman microspectroscopy in combination with counter-gradient freezing to evaluate the effect of a wide range of freezing temperatures (-20frozen formulation in only a few experiments. The freezing experiments conducted with a model system (albumin and trehalose) showed the presence of different degrees of MH in the freeze-concentrated liquid (FCL) in all solutions tested. Mainly, albumin tended to accumulate near the ice interface, where it was physically separated from the cryoprotectant. In frozen 10wt% trehalose solutions, heterogeneity in FCL was relatively low at any TF. In frozen 20wt% trehalose solutions, the optimum albumin to trehalose ratio in the FCL can only be ensured if the solution was frozen within a narrow range of temperatures (-16frozen and stable formulations and freezing protocols for biological as MH is presumed to directly impact stability.

  7. Microheterogeneity in Frozen Protein Solutions

    PubMed Central

    Twomey, Alan; Kurata, Kosaku; Nagare, Yutaka; Takamatsu, Hiroshi; Aksan, Alptekin

    2015-01-01

    In frozen and lyophilized systems, the biological to be stabilized (e.g. therapeutic protein, biomarker, drug-delivery vesicle) and the cryo-/lyoprotectant should be co-localized for successful stabilization. During freezing and drying, many factors cause physical separation of the biological from the cryo-/lyoprotectant, called microheterogeneity (MH), which may result in poor stabilization efficiency. We have developed a novel technique that utilized confocal Raman microspectroscopy in combination with counter-gradient freezing to evaluate the effect of a wide range of freezing temperatures (−20 < TF < 0°C) on the MH generated within a frozen formulation in only a few experiments. The freezing experiments conducted with a model system (albumin and trehalose) showed the presence of different degrees of MH in the freeze-concentrated liquid (FCL) in all solutions tested. Mainly, albumin tended to accumulate near the ice interface, where it was physically separated from the cryoprotectant. In frozen 10 wt% trehalose solutions, heterogeneity in FCL was relatively low at any TF. In frozen 20 wt% trehalose solutions, the optimum albumin to trehalose ratio in the FCL can only be ensured if the solution was frozen within a narrow range of temperatures (−16 < TF < −10°C). In the 30 wt% trehalose solutions, freezing within a much more narrow range (−12 < TF < −10°C) was needed to ensure a fairly homogeneous FCL. The method developed here will be helpful for the development of uniformly frozen and stable formulations and freezing protocols for biological as MH is presumed to directly impact stability. PMID:25888798

  8. Synthetic ion channels via self-assembly: a route for embedding porous polyoxometalate nanocapsules in lipid bilayer membranes.

    PubMed

    Carr, Rogan; Weinstock, Ira A; Sivaprasadarao, Asipu; Müller, Achim; Aksimentiev, Aleksei

    2008-11-01

    Porous polyoxometalate nanocapsules of Keplerate type are known to exhibit the functionality of biological ion channels; however, their use as an artificial ion channel is tempered by the high negative charge of the capsules, which renders their spontaneous incorporation into a lipid bilayer membrane unlikely. In this Letter we report coarse-grained molecular dynamics simulations that demonstrate a route for embedding negatively charged nanocapsules into lipid bilayer membranes via self-assembly. A homogeneous mixture of water, cationic detergent, and phospholipid was observed to spontaneously self-assemble around the nanocapsule into a layered, liposome-like structure, where the nanocapsule was enveloped by a layer of cationic detergent followed by a layer of phospholipid. Fusion of such a layered liposome with a lipid bilayer membrane was observed to embed the nanocapsule into the lipid bilayer. The resulting assembly was found to remain stable even after the surface of the capsule was exposed to electrolyte. In the latter conformation, water was observed to flow into and out of the capsule as Na(+) cations entered, suggesting that a polyoxometalate nanocapsule can form a functional synthetic ion channel in a lipid bilayer membrane.

  9. Synthetic Ion Channels via Self-Assembly: a Route for Embedding Porous Polyoxometalate Nanocapsules in Lipid Bilayer Membranes

    PubMed Central

    Carr, Rogan; Weinstock, Ira A.; Sivaprasadarao, Asipu; Müller, Achim; Aksimentiev, Aleksei

    2010-01-01

    Porous polyoxometalate nanocapsules of Keplerate type are known to exhibit the functionality of biological ion channels, however, their use as artificial ion channel is tempered by the high negative charge of the capsules, which renders their spontaneous incorporation into a lipid bilayer membrane unlikely. In this letter we report coarse-grained molecular dynamics simulations that demonstrate a route for embedding negatively charged nanocapsules into lipid bilayer membranes via self-assembly. A homogeneous mixture of water, cationic detergent, and phospholipid was observed to spontaneously self-assemble around the nanocapsule into a layered, liposome-like structure, where the nanocapsule was enveloped by a layer of cationic detergent followed by a layer of phospholipid. Fusion of such a layered liposome with a lipid bilayer membrane was observed to embed the nanocapsule into the lipid bilayer. The resulting assembly was found to remain stable even after the surface of the capsule was exposed to electrolyte. In the latter conformation, water was observed to flow into and out of the capsule as Na+ cations entered, suggesting that a polyoxometalate nanocapsule can form a functional synthetic ion channel in a lipid bilayer membrane. PMID:18844424

  10. Modulation of antioxidant and detoxifying capacity in fish Cyprinus carpio (Cyprinidae) after treatment with nanocapsules containing lipoic acid.

    PubMed

    Longaray-Garcia, Márcia; Flores, Juliana Artigas; Külkamp-Guerreiro, Irene Clemes; Guterres, Sílvia Stanisçuaski; Pereira, Talita Carneiro Brandão; Bogo, Maurício Reis; Monserrat, José Maria

    2013-08-01

    Lipoic acid (LA) is a water- and lipid-soluble molecule with capacity to pass through cell membranes and with several antioxidant properties. Previous studies have shown that polymeric nanocapsules with LA favor the protection of this antioxidant, increasing their physical and chemical stability compared to formulations containing free LA. The aim of this study was to evaluate and compare the effect of free LA and LA-nanocapsules on antioxidant enzymes, the concentration of reduced glutathione (GSH) and a by-product of lipid peroxidation (malondialdehyde), as well as the expression of gene coding for different forms of glutathione-S-transferase (GST) in model fish. For this, carp Cyprinus carpio (Cyprinidae) were exposed (i.p.) to different forms of LA (free and in nanocapsules) for different times (48h, 96h and 1week) and the brain, liver and muscle were analyzed. Results indicated that the organs respond differently depending on the time and form in which LA was delivered. After 96h and 1week, a better antioxidant response was found generally in the formulation with nanocapsules. The nanocapsule composition showed to be a factor to be considered in future studies, because in some organs and exposure times empty nanocapsules promoted an antioxidant effect and in others a pro-oxidant effect.

  11. Hydrogels containing redispersible spray-dried melatonin-loaded nanocapsules: a formulation for transdermal-controlled delivery

    PubMed Central

    2012-01-01

    The aim of the present study was to develop a transdermal system for controlled delivery of melatonin combining three strategies: nanoencapsulation of melatonin, drying of melatonin-loaded nanocapsules, and incorporation of nanocapsules in a hydrophilic gel. Nanocapsules were prepared by interfacial deposition of the polymer and were spray-dried using water-soluble excipients. In vitro drug release profiles were evaluated by the dialysis bag method, and skin permeation studies were carried out using Franz cells with porcine skin as the membrane. The use of 10% (w/v) water-soluble excipients (lactose or maltodextrin) as spray-drying adjuvants furnished redispersible powders (redispersibility index approximately 1.0) suitable for incorporation into hydrogels. All formulations showed a better controlled in vitro release of melatonin compared with the melatonin solution. The best controlled release results were achieved with hydrogels prepared with dried nanocapsules (hydrogels > redispersed dried nanocapsules > nanocapsule suspension > melatonin solution). The skin permeation studies demonstrated a significant modulation of the transdermal melatonin permeation for hydrogels prepared with redispersible nanocapsules. In this way, the additive effect of the different approaches used in this study (nanoencapsulation, spray-drying, and preparation of semisolid dosage forms) allows not only the control of melatonin release, but also transdermal permeation. PMID:22587614

  12. Coordination polymer nanocapsules prepared using metal-organic framework templates for pH-responsive drug delivery

    NASA Astrophysics Data System (ADS)

    Tang, Lei; Shi, Jiafu; Wang, Xiaoli; Zhang, Shaohua; Wu, Hong; Sun, Hongfan; Jiang, Zhongyi

    2017-07-01

    A facile, efficient, and versatile approach is presented to synthesize pH-responsive nanocapsules (˜120 nm) by combining the advantages of metal-organic frameworks (MOFs) and metal-organic thin films. ZIF-8 nanoparticles are used as templates on which a thin film coating of iron(III)-catechol complexes is derived from the coordination between dopamine-modified alginate (AlgDA) and iron(III) ions. After the template removal, nanocapsules with a pH-responsive wall are obtained. Doxorubicin (Dox), a typical anticancer drug, is first immobilized in ZIF-8 frameworks through coprecipitation and then encapsulated in nanocapsules after the removal of ZIF-8. The structure of the iron(III)-catechol complex varies with pH value, thus conferring the Dox@Nanocapsules with tailored release behavior in vitro. Cytotoxicity tests illustrate the highly effective cytotoxicity of Dox@Nanocapsules towards cancer cells. This study provides a new method for preparing smart nanocapsules and offers more opportunities for the controlled delivery of drugs.

  13. Pulse Transmission through Frozen Silt,

    DTIC Science & Technology

    1984-07-01

    THROUGH FROZEN SILT 6. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(s) 8. CONTRACT OR GRANT NUMBER(e) Steven A. Arcone 9. PERFORMING ORGANIZATION NAME AND...SECURITY CLASSIFICATION OF THIS PAGE (When Dots Entered) PREFACE This report was prepared by Dr. Steven A. Arcone , Research Geophysicist, Snow and Ice...GRA&I A w ,.,.TAB L u :,nnr-ane’ed n --." ~~~i f teation--- - ! i . Avaii and/orC in I+ PULSE TRANSMISSION THROUGH FROZEN SILT Steven A. Arcone

  14. [Rapid frozen sections in neuropathology].

    PubMed

    Haybaeck, J; von Campe, G; Hainfellner, J A

    2012-09-01

    Neuropathological evaluation of frozen sections requires a) special expertise in neuropathological specimen assessment and neurooncology as well as b) a trustful and open communication culture with the neurosurgeons. In addition to frozen sections, cytological examinations of smear and touch preparations as supporting methods are available to reach a correct diagnosis: these additional methods should therefore be performed whenever possible. Besides evaluation of biopsy specimens, appraisal of resection specimens and resection margin controls are of high clinical relevance. In the case of diffusely infiltrating central nervous system (CNS) neoplasms, in particular gliomas, resection margin control is often not feasible in contrast to other types of solid tumor.

  15. Lipidic nanocapsule drug delivery: neuronal protection for cochlear implant optimization

    PubMed Central

    Meyer, Hartwig; Stöver, Timo; Fouchet, Florian; Bastiat, Guillaume; Saulnier, Patrick; Bäumer, Wolfgang; Lenarz, Thomas; Scheper, Verena

    2012-01-01

    Objective Sensorineural hearing loss leads to the progressive degeneration of spiral ganglion cells (SGC). Next to postoperative fibrous tissue growth, which should be suppressed to assure a close nerve–electrode interaction, the density of healthy SGC is one factor that influences the efficiency of cochlear implants (CI), the choice of treatment for affected patients. Rolipram, a phosphodiesterase-4 inhibitor, has proven neuroprotective and anti-inflammatory effects and might also reduce SGC degeneration and fibrosis, but it has to pass the cellular membrane to be biologically active. Methods Lipidic nanocapsules (LNC) can be used as biodegradable drug carriers to increase the efficacy of conventional application methods. We examined the biological effects of rolipram and LNC’s core encapsulated rolipram on SGC and dendritic cell (DC) tumor necrosis factor-α (TNF-α) production in vitro and on SGC survival in systemically-deafened guinea pigs in vivo. Results Our results prove that rolipram does not have a beneficial effect on cultured SGC. Incorporation of rolipram in LNC increased the survival of SGC significantly. In the DC study, rolipram significantly inhibited TNF-α in a dose-dependent manner. The rolipram-loaded LNC provided a significant cytokine inhibition as well. In vivo data do not confirm the in vitro results. Conclusion By transporting rolipram into the SGC cytoplasm, LNC enabled the neuroprotective effect of rolipram in vitro, but not in vivo. This might be due to dilution of test substances by perilymph or an inadequate release of rolipram based on differing in vivo and in vitro conditions. Nevertheless, based on in vitro results, proving a significantly increased neuronal survival when using LNC-rolipram compared to pure rolipram and pure LNC application, we believe that the combination of rolipram and LNC can potentially reduce neuronal degeneration and fibrosis after CI implantation. We conclude that rolipram is a promising drug that can

  16. Optimisation of rosemary oil encapsulation in polycaprolactone and scale-up of the process.

    PubMed

    Ephrem, Elissa; Greige-Gerges, Hélène; Fessi, Hatem; Charcosset, Catherine

    2014-01-01

    Rosemary essential oil (REO) has many biological activities, such as antioxidant, anticarcinogenic, cognition-enhancing, analgesic and antimicrobial activities. The aim of this study was to prepare, at laboratory scale and larger scale, nanoencapsulating REO in order to reduce its volatilisation, light sensitivity and to enhance its water solubility. The nanoprecipitation method was applied to prepare polycaprolactone (PCL)-based nanocapsules loaded with REO at laboratory scale and then the optimal formulation obtained was scaled-up (×6) using the membrane contactor technique. The effect of several parameters, such as the evaporation method, the type of emulsifiers and the amount of the formulation products (PCL, REO, emulsifiers, etc.) on the REO-loaded nanocapsules properties (mean size, polydispersity index (PdI), zeta potential and REO loss) was evaluated at laboratory scale in order to obtain the optimal formulation. REO-loaded nanocapsules obtained from nanoprecipitation presented a nanometric mean size (220 ± 10 nm) with a PdI below 0.25, indicating an adequate homogeneity of the system, a negative zeta potential (-19.9 ± 4.6 mV) and a high encapsulation efficiency (∼99% for the major components). In addition, the membrane contactor technique gave similar results using an adequate pressure of the organic phase (0.8-1.2 bar). It is then suggested that the nanoprecipitation method can be suitable for the preparation of essential oil-loaded nanocapsules.

  17. Resolving disputes over frozen embryos.

    PubMed

    Robertson, J A

    1989-01-01

    The relation between respect for family and reproductive choice and use of IVF technology is in dispute in recent legal cases on the disposition of frozen embryos. Couples in IVF programs should be encouraged to stipulate in advance binding instructions regarding the disposition of such embryos.

  18. Frozen Scope and Grammatical Optimization

    ERIC Educational Resources Information Center

    Freedman, Michael

    2014-01-01

    The literature on quantifier scope has repeatedly observed that some otherwise expected permutations of scope taking elements are unavailable. Various methods have been proffered explaining these facts. This thesis aims to unify three disparate areas where the scope of operators seems to be frozen: the interaction of universal quantifiers with…

  19. 'Frozen finger' in anal fissures.

    PubMed

    Chintamani; Tandon, Megha; Khandelwal, Rohan

    2009-10-01

    Acute anal fissures are usually managed by various invasive and non-invasive modalities ranging from simple lifestyle changes to chemical and surgical sphincterotomies. Frozen finger, prepared using a water-filled ordinary rubber glove, was successfully used in one hundred patients, thus providing a cost-effective and simple solution to the problem.

  20. Frozen Scope and Grammatical Optimization

    ERIC Educational Resources Information Center

    Freedman, Michael

    2014-01-01

    The literature on quantifier scope has repeatedly observed that some otherwise expected permutations of scope taking elements are unavailable. Various methods have been proffered explaining these facts. This thesis aims to unify three disparate areas where the scope of operators seems to be frozen: the interaction of universal quantifiers with…

  1. The Eccentric Behavior of Nearly Frozen Orbits

    NASA Technical Reports Server (NTRS)

    Sweetser, Theodore H.; Vincent, Mark A.

    2013-01-01

    Frozen orbits are orbits which have only short-period changes in their mean eccentricity and argument of periapse, so that they basically keep a fixed orientation within their plane of motion. Nearly frozen orbits are those whose eccentricity and argument of periapse have values close to those of a frozen orbit. We call them "nearly" frozen because their eccentricity vector (a vector whose polar coordinates are eccentricity and argument of periapse) will stay within a bounded distance from the frozen orbit eccentricity vector, circulating around it over time. For highly inclined orbits around the Earth, this distance is effectively constant over time. Furthermore, frozen orbit eccentricity values are low enough that these orbits are essentially eccentric (i.e., off center) circles, so that nearly frozen orbits around Earth are bounded above and below by frozen orbits.

  2. 7 CFR 58.327 - Frozen cream.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.327 Frozen cream. To produce frozen cream eligible for official certification, the quality...

  3. 7 CFR 58.327 - Frozen cream.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.327 Frozen cream. To produce frozen cream eligible for official certification, the quality...

  4. 7 CFR 58.327 - Frozen cream.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.327 Frozen cream. To produce frozen cream eligible for official certification, the quality...

  5. 7 CFR 58.327 - Frozen cream.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.327 Frozen cream. To produce frozen cream eligible for official certification, the quality...

  6. 7 CFR 58.327 - Frozen cream.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Frozen cream. 58.327 Section 58.327 Agriculture... Material § 58.327 Frozen cream. To produce frozen cream eligible for official certification, the quality of the cream used shall meet the requirements of cream acceptable for the manufacture of U.S. Grade AA...

  7. Surface Functionalization of Titanium Alloy with miR-29b Nanocapsules To Enhance Bone Regeneration.

    PubMed

    Meng, Yubin; Li, Xue; Li, Zhaoyang; Liu, Chaoyong; Zhao, Jin; Wang, Jianwei; Liu, Yunde; Yuan, Xubo; Cui, Zhenduo; Yang, Xianjin

    2016-03-09

    Titanium and its alloys have been widely used over the past 3 decades as implants for healing bone defects. Nevertheless, the bioinert property of titanium alloy limits its clinical application and surface modification method is frequently performed to improve the biological and chemical properties. Recently, the delivery of microRNA with osteogenesis capability has been recognized as a promising tool to enhance bone regeneration of implants. Here, we developed a biodegradable coating to modify the titanium surface in order to enhance osteogenic bioactivity. The previous developed nanocapsules were used as the building blocks, and then a bioactive titanium coating was designed to entrap the miR-29b nanocapsules. This coating was not only favorable for cell adhesion and growth but also provided sufficient microRNA transfection efficacy and osteoinductive potential, resulting in a significant enhancement of bone regeneration on the surface of bioinert titanium alloy.

  8. Aminoglutethimide included in nanocapsules suspension: comparison of GC-MS and HPLC methods for control.

    PubMed

    Berrabah, M; Andre, D; Verite, P; Zahidi, A; Lafont, O

    2004-06-29

    Gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC) offer highly efficient and potentially sensitive separation and detection techniques. This work describes the quantification of aminoglutethimide (AG) in nanocapsules suspension with both techniques. The analysis of different lots containing known concentrations of drug (1, 2, 3 and 4 mg ml(-1)) were used to investigate the quantitative capabilities of both chromatographic techniques. Both chromatographic methods were successful and on an analytical point of view the validations of aminoglutethimide dosing were suitable in both cases. In routine, the determination of the quality of nanocapsules suspension could be preferentially evaluated by difference between total AG concentration in suspension (evaluated by direct HPLC measure of the suspension diluted in acetonitrile) and free AG concentration (evaluated by direct HPLC measure of simple dilution of the supernatant). Copyright 2004 Elsevier B.V.

  9. Synthesis of monodisperse hollow carbon nanocapsules by using protective silica shells.

    PubMed

    Quan, Bo; Nam, Gi-Eun; Choi, Hyuck Jae; Piao, Yuanzhe

    2013-04-01

    Monodisperse hollow carbon nanocapsules (<200 nm) with mesoporous shells were synthesized by coating their outer shells with silica to prevent aggregation during their high-temperature annealing. Monodispersed silica nanoparticles were used as starting materials and octadecyltrimethoxysilane (C18TMS) was used as a carbon source to create core-shell nanostructures. These core-shell nanoparticles were coated with silica on their outer shell to form a second shell layer. This outer silica shell prevented aggregation during calcination. The samples were characterized by TEM, SEM, dynamic light scattering (DLS), UV/Vis spectroscopy, and by using the Brunauer-Emmett-Teller (BET) method. The as-synthesized hollow carbon nanoparticles exhibited a high surface area (1123 m(2) g(-1)) and formed stable dispersions in water after the pegylation process. The drug-loading and drug-release properties of these hollow carbon nanocapsules were also investigated. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Rattle-type hollow CaWO4:Tb(3+)@SiO2 nanocapsules as carriers for drug delivery.

    PubMed

    Zhai, Xuefeng; Yu, Min; Cheng, Ziyong; Hou, Zhiyao; Ma, Ping'an; Yang, Dongmei; Kang, Xiaojiao; Dai, Yunlu; Wang, Dong; Lin, Jun

    2011-12-28

    Rattle-type hollow nanocapsules are among of the most promising candidates as drug carriers owing to their huge inner space and multifunctional material combination. In this paper, rattle-type hollow CaWO(4):Tb(3+)@SiO(2) nanocapsules with a diameter of 100-110 nm and a wall thickness around 10 nm were fabricated. The hollow silica nanospheres were used as nano-reactors and the luminescent core of CaWO(4):Tb(3+) was post-filled into the nano-reactors by a vacuum nano-casting route combined with a Pechini-type sol-gel method. Subsequently, doxorubicin hydrochloride (DOX), a model of an anti-cancer drug, is loaded into the CaWO(4):Tb(3+)@SiO(2) nanocapsules and their cell cytotoxicity, cancer cell uptake and drug release behavior are investigated in vitro. The prepared multifunctional inorganic nanocapsules show a loading capacity for DOX as high as 124 mg g(-1) and sustained-release properties. The release profile of the drug from DOX-loaded nanocapsules can last over five days. Besides, the blank CaWO(4):Tb(3+)@SiO(2) shows very low cytotoxicity against cancer cell lines (HeLa cell) while the DOX-loaded nanocapsules exhibit relatively high efficiency for killing of HeLa cells. The rapid cancer cell uptake process is observed by confocal laser scanning microscopy. The results indicate that a rattle-type hollow CaWO(4):Tb(3+)@SiO(2) nanocapsule has the potential to be used as drug carrier in therapy. Moreover, it is possible to extend the synthetic strategy in this study to other rattle-type multifunctional composites to meet various demands. This journal is © The Royal Society of Chemistry 2011

  11. Bio-nanocapsules for signal enhancement of alkaline phosphatase-linked immunosorbent assays.

    PubMed

    Iijima, Masumi; Yamamoto, Mikako; Yoshimoto, Nobuo; Niimi, Tomoaki; Kuroda, Shun'ichi

    2013-01-01

    The bio-nanocapsules displaying about 240 molecules of immunoglobulin G Fc-binding Z domains (ZZ-BNCs) enhanced the signals of enzyme-linked immunosorbent assay by tethering the Fc regions of secondary antibodies (Abs), which were eliminated using high-molecular mass enzymes (e.g., alkaline phosphatase). By way of optimizing the distance between enzymes and Abs, ZZ-BNCs improved sensitivity independently of enzymes.

  12. Cell-Demanded VEGF Release via Nanocapsules Elicits Different Receptor Activation Dynamics and Enhanced Angiogenesis.

    PubMed

    Zhu, Suwei; Segura, Tatiana

    2016-06-01

    Although the delivery of vascular endothelial growth factor (VEGF) with extended release profiles has consistently shown beneficial therapeutic effects compared with bolus delivery, [Martino, M. M., F. Tortelli, M. Mochizuki, S. Traub, D. Ben-David, G. A. Kuhn, R. Muller, E. Livne, S. A. Eming, and J. A. Hubbell. Sci. Transl. Med. 3(100):100ra189, 2011; Martino, M. M., P. S. Briquez, A. Ranga, M. P. Lutolf, and J. A. Hubbell. Proc. Natl. Acad. Sci. USA. 110(12):4563-4568, 2013; Amiram, M., K. M. Luginbuhl, X. Li, M. N. Feinglos, and A. Chilkoti. Proc. Natl. Acad. Sci. USA. 110(8):2792-2797, 2013] it remains unclear if the reason is solely due to the physical availability and the reduced degradation of the protein. Here we studied the activation of VEGF receptor 2 (VR-2) by sustained released VEGF compared with bolus delivered VEGF to unveil that sustained delivery system alters the dynamics of receptor activation and affects the actions of cells between sprouting and proliferation. We utilized a protein nanocapsule delivery strategy that releases VEGF as mediated by extracellular proteases. These protein nanocapsules were synthesized through an aqueous assembly of a nanogel-peptide shell around the protein, leading to one to two proteins encapsulated per nanocapsule. Receptor activation studies revealed differential dynamics of receptor activation for slowly released VEGF compared with bolus delivered VEGF. As expected sustained released VEGF via nanocapsules resulted in enhanced vascular sprouting in vitro and in vivo. These studies demonstrate the physical presentation of VEGF, in this case of a slow release with time, can affect its molecular mechanism of actions and cause alterations in cellular responses and therapeutic outcomes.

  13. Preparation, characterization and applications of low-molecular-weight alginate-oligochitosan nanocapsules

    NASA Astrophysics Data System (ADS)

    Wang, Ting; He, Nongyue

    2010-02-01

    The development of drug-delivering nanoparticles from natural materials for various biomedical applications is an area of great promise. However, the contradictory data on their uncontrollable diameter, unstable structure and toxic effects, highlight the need to study their preparation, characterization and cytotoxic effects in cells. In this work, nanocapsules are made from a type of W/O microemulsion system with low-molecular-weight alginate (LMWALG) and oligochitosan (OCS). The particles possess excellent biocompatibility and good biodegradability. The size of capsules is controlled and optimized by carefully adjusting the molecular weight and concentration of LMWALG and OCS. We found, from orthogonal experiments, the encapsulation time leading to a uniform size distribution with an average diameter of 136 nm. Furthermore, we found that molecular weights of LMWALG and OCS significantly influence the stability and size of capsules. The optimized nanocapsules are further used to study the drug release of BSA. Results show that the efficiency of encapsulation approximately reaches 88.4% and the concentration of BSA in phosphate-buffered solution (PBS, pH = 7.4) is well maintained at a level of 35 to 40% from 12 h to 48 h, due to the stable and slow degradation of the nanocapusules. The biocompatibility of LMWALG/OCS nanocapsules is cross-examined by cytotoxicity experiments and acute systemic toxicological tests, and they were found to enhance the survival rate of the cells from 80.30 to 95.39% in 7 days. The synthesized nanocapsules exhibit high biocompatibility, non-toxicity, biodegradation, and uniform size, providing a new potential candidate for drug releases in clinic experiments.

  14. 21 CFR 101.95 - “Fresh,” “freshly frozen,” “fresh frozen,” “frozen fresh.”

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false âFresh,â âfreshly frozen,â âfresh frozen,â âfrozen... frozen,” “fresh frozen,” “frozen fresh.” The terms defined in this section may be used on the label or in... state and has not been frozen or subjected to any form of thermal processing or any other form...

  15. Biodegradable Poly (Lactic-co-Glycolic Acid)-Polyethylene Glycol Nanocapsules: An Efficient Carrier for Improved Solubility, Bioavailability, and Anticancer Property of Lutein.

    PubMed

    Arunkumar, Ranganathan; Prashanth, Keelara Veerappa Harish; Manabe, Yuki; Hirata, Takashi; Sugawara, Tatsuya; Dharmesh, Shylaja Mallaiah; Baskaran, Vallikannan

    2015-06-01

    Lutein bioavailability is limited because of its poor aqueous solubility. In this study, lutein-poly (lactic-co-glycolic acid) (PLGA)-polyethylene glycol (PEG) nanocapsules were prepared to improve the solubility, bioavailability, and anticancer property of lutein. The scanning electron microscopy and dynamic light scattering examination revealed that the nanocapsules are smooth and spherical with size ranging from 80 to 500 nm (mean = 200 nm). In vitro lutein release profile from nanocapsules showed controlled sustainable release (66%) up to 72 h. Aqueous solubility of lutein nanocapsules was much higher by 735-fold than the lutein. Fourier transform infrared spectroscopy analyses showed no chemical interaction among PLGA, PEG, and lutein, indicating possible weak intermolecular forces like hydrogen bonds. X-ray diffraction revealed lutein is distributed in a disordered amorphous state in nanocapsules. Postprandial plasma kinetics (area under the curve) of an oral dose of lutein from nanocapsules was higher by 5.4-fold compared with that of micellar lutein (control). The antiproliferative effect of lutein from nanocapsules (IC50 value, 10.9 μM) was higher (43.6%) than the lutein (IC50 value, 25 μM). Results suggest that PLGA-PEG nanocapsule is an efficient carrier for enhancing hydrophilicity, bioavailability, and anticancer property of lipophilic molecules such as lutein.

  16. Synthesis and characterization of nanocapsules with shells made up of Al13 tridecamers.

    PubMed

    Bokhimi, Xim; Lima, Enrique; Valente, Jaime

    2005-12-01

    The synthesis of samples by the sol-gel method with aluminum tri-sec-butoxide as cation precursor, 2-propanol as solvent, and sulfuric acid as hydrolysis catalyst gave rise to nanocapsules with an average diameter of 20 nm and a shell thickness of 3.5 nm. The analysis of the X-ray diffraction patterns and the 27Al MAS NMR spectra showed that the shell of the nanocapsules was made up of Al13 tridecamers ordered in a noncrystalline symmetry. The interaction between the capsule's shells opened the capsule structure, producing curved fibers, but maintaining the atomic local order. This opening of the capsules favored the reordering of the atomic local order of Al13 tridecamers into the one of crystalline boehmite, when the sample was aged at room temperature for several days; it also increased the pore volume and the specific surface area of the sample. The crystallization transformed the curved fibers into rods made of small crystalline boehmite bars. The capsule morphology was preserved after calcining the nonaged sample at 700 degrees C, indicating that the transformation of the phase made up of ordered Al13 tridecamers into a noncrystalline alumina was pseudomorphic. We describe and partially explain one of the possible atomic ordering evolutions from the one of an isolated Al13 tridecamer, to the phase forming the nanocapsules shell, until eventually coming to the ordering corresponding to boehmite crystalline rods.

  17. Suppressing unspecific cell uptake for targeted delivery using hydroxyethyl starch nanocapsules.

    PubMed

    Baier, Grit; Baumann, Daniela; Siebert, Jörg Max; Musyanovych, Anna; Mailänder, Volker; Landfester, Katharina

    2012-09-10

    Synthesizing nanocarriers with stealth properties and delivering a "payload" to the particular organ remains a big challenge but is the prime prerequisite for any in vivo application. As a nontoxic alternative to the modification by poly(ethylene glycol) PEG, we describe the synthesis of cross-linked hydroxyethyl starch (HES, M(w) 200,000 g/mol) nanocapsules with a size range of 170-300 nm, which do not show nonspecific uptake into cells. The specific uptake was shown by coupling a folic acid conjugate as a model targeting agent onto the surface of the nanocapsules, because folic acid has a high affinity to a variety of human carcinoma cell lines which overexpress the folate receptor on the cell surface. The covalent binding of the folic acid conjugate onto HES capsules was confirmed by FTIR and NMR spectroscopy. The coupling efficiency was determined using fluorescence spectroscopy. The specific cellular uptake of the HES nanocapsules after folic acid coupling into the folate-receptor presenting cells was studied by confocal laser scanning microscopy (CLSM) and flow cytometry.

  18. Development of stained polymeric nanocapsules loaded with model drugs: Use of a fluorescent poly(phenyleneethynylene).

    PubMed

    Campos, Estefânia V R; Oliveira, Jhones L; Zavala-Betancourt, Sara A; Ledezma, Antonio S; Arias, Eduardo; Moggio, Ivana; Romero, Jorge; Fraceto, Leonardo F

    2016-11-01

    A phenyleneethynylene polymer (here denoted pPy3E-sqS) was synthesized and characterized by UV-vis spectroscopy, fluorescence spectroscopy, and TEM, and was used for the staining of polymeric nanocapsules. The nanocapsules presented good temporal stability, without changes in shape or fluorescence, and were suitable for use in drug release systems. The mean particle size was around 430nm, the polydispersity index was below 0.2, and the zeta potential was around -13mV. The release kinetics is one of the most important factors to consider in drug delivery systems, and here it was observed that nanocapsules containing the fluorescent polymer still maintained the ability to modulate the release of the fungicides tebuconazole and carbendazim (used as model drugs) after 4days. Preliminary results indicated that staining with the fluorescent pPy3E-sqS polymer could be used as a valuable tool to track the behavior of polymeric systems in the environment. However, further studies will be needed to clarify the environmental behavior and possible toxicity.

  19. Encapsulation of antiviral nucleotide analogues azidothymidine-triphosphate and cidofovir in poly(iso-butylcyanoacrylate) nanocapsules.

    PubMed

    Hillaireau, H; Le Doan, T; Besnard, M; Chacun, H; Janin, J; Couvreur, P

    2006-10-31

    Nucleoside analogues are widely used in the treatment of various viral infections. However, the poor in vivo conversion of the nucleoside analogues like azidothymidine (AZT) into their active triphosphate nucleotide counterpart limits their pharmacological efficacy. This could be overcome by the direct administration of azidothymidine triphosphate (AZT-TP), but it requires an appropriate drug delivery approach. Besides nucleoside analogues, nucleotide analogues like cidofovir (CDV) are also used in the treatment of viral infections. CDV has raised recent interest because of its promising activity against smallpox, but its use is limited by its poor bioavailability and nephrotoxicity. Here again, a proper drug delivery system should address these issues. In this study, we investigated the encapsulation of the nucleotide analogues AZT-TP and CDV into poly(iso-butylcyanoacrylate) aqueous core nanocapsules, known to efficiently entrap oligonucleotides. We show here that the encapsulation of these mono-nucleotides is less efficient than with oligonucleotides and that a rapid release of AZT-TP from the nanocapsules occurred in vitro. This highlights the importance of the molecular weight of the entrapped molecules which, if they are too small, are diffusing through the thin polymer membrane of the nanocapsules. On the other hand, a good protection of the encapsulated AZT-TP was observed.

  20. Dual-Color Emissive Upconversion Nanocapsules for Differential Cancer Bioimaging In Vivo.

    PubMed

    Kwon, Oh Seok; Song, Hyun Seok; Conde, João; Kim, Hyoung-Il; Artzi, Natalie; Kim, Jae-Hong

    2016-01-26

    Early diagnosis of tumor malignancy is crucial for timely cancer treatment aimed at imparting desired clinical outcomes. The traditional fluorescence-based imaging is unfortunately faced with challenges such as low tissue penetration and background autofluorescence. Upconversion (UC)-based bioimaging can overcome these limitations as their excitation occurs at lower frequencies and the emission at higher frequencies. In this study, multifunctional silica-based nanocapsules were synthesized to encapsulate two distinct triplet-triplet annihilation UC chromophore pairs. Each nanocapsule emits different colors, blue or green, following a red light excitation. These nanocapsules were further conjugated with either antibodies or peptides to selectively target breast or colon cancer cells, respectively. Both in vitro and in vivo experimental results herein demonstrate cancer-specific and differential-color imaging from single wavelength excitation as well as far greater accumulation at targeted tumor sites than that due to the enhanced permeability and retention effect. This approach can be used to host a variety of chromophore pairs for various tumor-specific, color-coding scenarios and can be employed for diagnosis of a wide range of cancer types within the heterogeneous tumor microenvironment.

  1. Paclitaxel-loaded PEGylated nanocapsules of perfluorooctyl bromide as theranostic agents.

    PubMed

    Boissenot, Tanguy; Fattal, Elias; Bordat, Alexandre; Houvenagel, Sophie; Valette, Julien; Chacun, Hélène; Gueutin, Claire; Tsapis, Nicolas

    2016-11-01

    We optimize the encapsulation of paclitaxel (PTX) into nanocapsules made of a shell of poly(lactide-co-glycolide)-polyethylene glycol and a core of perfluorooctyl bromide (PFOB) to serve as theranostic agents. Two main challenges were met: keeping the imaging moiety (PFOB) encapsulated while loading the polymer shell with a hydrophobic drug very prone to crystallization. Encapsulation is performed by a modified emulsion-evaporation method leading to 120nm diameter nanocapsules with a drug loading compatible with tumor treatment. The optimized formulation tested in vitro on CT-26 colon cancer cells yields a similar IC50 as the generic Taxol® formulation. In vivo, (19)F-MRI shows that PTX encapsulation does not modify the ability of nanocapsules to accumulate passively in CT-26 tumors in mice by the enhanced permeation and retention (EPR) effect. This accumulation leads to a promising and statistically significant twofold reduction in tumor growth as compared with negative control and generic Taxol® group. Altogether these results advocate for an interesting potential of these paclitaxel-loaded theranostic agents. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Inhibition of ectopic glioma tumor growth by a potent ferrocenyl drug loaded into stealth lipid nanocapsules.

    PubMed

    Lainé, Anne-Laure; Clavreul, Anne; Rousseau, Audrey; Tétaud, Clément; Vessieres, Anne; Garcion, Emmanuel; Jaouen, Gerard; Aubert, Léo; Guilbert, Matthieu; Benoit, Jean-Pierre; Toillon, Robert-Alain; Passirani, Catherine

    2014-11-01

    In this work, a novel ferrocenyl complex (ansa-FcdiOH) was assessed for brain tumor therapy through stealth lipid nanocapsules (LNCs). Stealth LNCs, prepared according to a one-step process, showed rapid uptake by cancer cells and extended blood circulation time. The ferrocenyl complex was successfully encapsulated into these LNCs measuring 40 nm with a high loading capacity (6.4%). In vitro studies showed a potent anticancer effect of ansa-FcdiOH on 9L cells with a low IC50 value (0.1 μM) associated with an oxidative stress and a dose-dependent alteration of the cell cycle. Repeated intravenous injections of stealth ansa-FcdiOH LNCs in ectopic glioma bearing rats induced a significant tumor growth inhibition, supported by a reduced number of proliferative cells in tumors compared to control group. Additionally, no liver damage was observed in treated animals. These results indicated that stealth ansa-FcdiOH LNCs might be considered as a potential new approach for cancer chemotherapy. In this study, a novel ferrocenyl complex was assessed for brain tumor therapy through stealth lipid nanocapsules, demonstrating no liver damage, and superior tumor volume reduction compared to saline and stealth lipid nanocapsules alone in an ectopic glioma model. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Carvedilol-loaded nanocapsules: Mucoadhesive properties and permeability across the sublingual mucosa.

    PubMed

    Chaves, Paula Dos Santos; Ourique, Aline Ferreira; Frank, Luiza Abrahão; Pohlmann, Adriana Raffin; Guterres, Sílvia Stanisçuaski; Beck, Ruy Carlos Ruver

    2017-05-01

    Carvedilol is a drug used to treat heart failure, hypertension, and coronary artery diseases . However, it has low oral bioavailability (25-35%) due to its high first-pass hepatic metabolism. The objective of this study was to develop carvedilol-loaded mucoadhesive nanocapsules as delivery systems for the sublingual administration of the drug. Nanocapsules were prepared using poly(ε-caprolactone) (CAR-LNC) and Eudragit® RS 100 (CAR-NC) as polymeric wall. In vitro interaction of formulations with mucin was performed to predict their mucoadhesion capacity. The permeability and washability profiles of carvedilol were evaluated using porcine sublingual mucosa. The mean diameter of particles in formulations was in the nanometric range, and particles had low polydispersity and slightly acidic pH. Zeta potential values were positive for CAR-NC and negative for CAR-LNC. Encapsulation efficiency was higher than 87% and 99% for CAR-NC and CAR-LNC, respectively. Both formulations presented controlled drug release profiles and mucoadhesive properties. Carvedilol was able to permeate through the sublingual mucosa. Nanoencapsulation improved retention time on the mucosa and permeation in presence of simulated salivary flux. This study highlighted the suitability of using CAR-loaded nanocapsules in the development of innovative sublingual dosage forms.

  4. The JLab Frozen Spin Target

    SciTech Connect

    Keith, C. D.

    2009-08-04

    A polarized, frozen spin target has been designed and constructed at Jefferson Lab for use inside the CEBAF Large Acceptance Spectrometer. Protons in TEMPO-doped butanol are polarized via dynamic nuclear polarization (DNP) to approximately 90% using microwaves and an external, 5 T solenoid magnet. The target sample is then cooled to approximately 30 mK while an internal 0.56 T superconducting magnet is used to maintain the polarization. Relaxation times in excess of 3500 hours have been observed.

  5. Acidity of frozen electrolyte solutions.

    PubMed

    Robinson, Carmen; Boxe, C S; Guzman, M I; Colussi, A J; Hoffmann, M R

    2006-04-20

    Ice is selectively intolerant to impurities. A preponderance of implanted anions or cations generates electrical imbalances in ice grown from electrolyte solutions. Since the excess charges are ultimately neutralized via interfacial (H(+)/HO(-)) transport, the acidity of the unfrozen portion can change significantly and permanently. This insufficiently recognized phenomenon should critically affect rates and equilibria in frozen media. Here we report the effective (19)F NMR chemical shift of 3-fluorobenzoic acid as in situ probe of the acidity of extensively frozen electrolyte solutions. The sign and magnitude of the acidity changes associated with freezing are largely determined by specific ion combinations, but depend also on solute concentration and/or the extent of supercooling. NaCl solutions become more basic, those of (NH(4))(2)SO(4) or Na(2)SO(4) become more acidic, while solutions of the 2-(N-morpholino)ethanesulfonic acid zwitterion barely change their acidity upon freezing. We discuss how acidity scales based on solid-state NMR measurements could be used to assess the degree of ionization of weak acids and bases in frozen media.

  6. Thawing of Frozen Tuna Meat

    NASA Astrophysics Data System (ADS)

    Tanaka, Takeo; Nishiwaki, Kôji; Kakuda, Kitonari; Tomimatsu, Takao

    Frozen southern bluefin tuna meat discolors easily and sometimes contracts when thawed caused by thaw rigor. These phenomenon often become problematic in the transaction or handling of this kind of frozen tuna. Frozen meat blocks of southern Bluefin tuna were thawed separately by air thawing, running water thawing and microwave thawing. Changes occurring during thawing were checked for meat color by met-myoglobin ratio determination and for contract by microscopic observation. Results are as follows : (1) Discoloration scarcely occurred in the process of running water thawing (at 10°C for 50 min, or at 0°C for 6 hr). (2) No contraction was observed during thawing with running water described above and air thawing (at 18-20°C for 6 hr). (3) Discoloration and contraction seemed to be minimized, as to latently contractile blocks, when meat temperature passed through rapidly between -10°C and -5°C, and slowly (for 5-6 hr) between -5°C and -1°C. When the block was originally not contractile, discloration was minimized by rising meat temperature rapidly from -10°C to -l°C.

  7. Poly (ε-caprolactone) nanocapsules for oral delivery of raloxifene: process optimization by hybrid design approach, in vitro and in vivo evaluation.

    PubMed

    Aditya, N; Ravi, Punna Rao; Avula, Uday Sai Ranjan; Vats, Rahul

    2014-01-01

    Raloxifene HCl (RLX), a selective oestrogen receptor modulator, has low oral bioavailability (<2%) in humans due to its poor aqueous solubility and extensive first-pass metabolism in gut. In this study, we optimised the method of preparation for poly (ε-caprolactone) (PCL) based nanocapsules of RLX by double emulsion method (w/o/w). A hybrid design approach, Plackett-Burman design followed by rotatable central composite design, was used to arrive at the optimised formulation. The optimised formulation was subjected to in vitro and in vivo evaluation. RLX loaded nanocapsules were spherical in shape with particle size less than 200 nm and high encapsulation efficiency (>80%). RLX-loaded nanocapsules showed 2.1-fold increase in oral bioavailability compared to free RLX. IV pharmacokinetic studies indicated that RLX loaded into nanocapsule had significantly low clearance in comparison with free RLX. Designed nanocapsules showed promise as delivery systems to enhance oral bioavailability and in reducing clearance of raloxifene.

  8. The effect of functionalizing lipid nanocapsules with NFL-TBS.40-63 peptide on their uptake by glioblastoma cells.

    PubMed

    Balzeau, Julien; Pinier, Maud; Berges, Raphael; Saulnier, Patrick; Benoit, Jean-Pierre; Eyer, Joel

    2013-04-01

    We previously described a neurofilament derived cell-penetrating peptide, NFL-TBS.40-63, that specifically enters in glioblastoma cells where it disturbs the microtubule network both in vitro and in vivo. The aim of this study is to test whether this peptide can increase the targeted uptake by glioblastoma cells of lipid nanocapsules filled with Paclitaxel, and thus can increase their anti-proliferation in vitro and in vivo. Here, using the drop tensiometry we show that approximately 60 NFL-TBS.40-63 peptides can bind to one 50 nm lipid nanocapsule. When nanocapsules are filled with a far-red fluorochrome (DiD) and Paclitaxel, the presence of the NFL-TBS.40-63 peptide increases their uptake by glioblastoma cells in culture as evaluated by FACS analysis, and thus reduces their proliferation. Finally, when such nanocapsules were injected in mice bearing a glioma tumour, they are preferentially targeted to the tumour and reduce its progression. These results show that nanocapsules functionalized with the NFL-TBS.40-63 peptide represent a powerful drug-carrier system for glioma targeted treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Novel drug delivery system based on docetaxel-loaded nanocapsules as a therapeutic strategy against breast cancer cells.

    PubMed

    Sánchez-Moreno, Paola; Boulaiz, Houria; Ortega-Vinuesa, Juan Luis; Peula-García, José Manuel; Aránega, Antonia

    2012-01-01

    In the field of cancer therapy, lipid nanocapsules based on a core-shell structure are promising vehicles for the delivery of hydrophobic drugs such as docetaxel. The main aim of this work was to evaluate whether docetaxel-loaded lipid nanocapsules improved the anti-tumor effect of free docetaxel in breast cancer cells. Three docetaxel-loaded lipid nanocapsules were synthesized by solvent displacement method. Cytotoxic assays were evaluated in breast carcinoma (MCF-7) cells treated by the sulforhodamine B colorimetric method. Cell cycle was studied by flow cytometry and Annexin V-FITC, and apoptosis was evaluated by using propidium iodide assays. The anti-proliferative effect of docetaxel appeared much earlier when the drug was encapsulated in lipid nanoparticles than when it was free. Docetaxel-loaded lipid nanocapsules significantly enhanced the decrease in IC(50) rate, and the treated cells evidenced apoptosis and a premature progression of the cell cycle from G(1) to G(2)-M phase. The chemotherapeutic effect of free docetaxel on breast cancer cells is improved by its encapsulation in lipid nanocapsules. This approach has the potential to overcome some major limitations of conventional chemotherapy and may be a promising strategy for future applications in breast cancer therapy.

  10. Droplet freezing, docking, and the exchange of immiscible phase and surfactant around frozen droplets.

    PubMed

    Sgro, Allyson E; Chiu, Daniel T

    2010-07-21

    This paper describes a platform for cooling microfluidic chips so as to freeze aqueous droplets flowing in oil. Using a whole-chip cooling chamber, we can control the ambient temperature surrounding a microfluidic chip and induce cooling and freezing inside the channels. When combined with a droplet generation and droplet docking chip, this platform allows for the facile freezing of droplets immobilized in resistance-based docks. Depending on the design and shape of the docks, the frozen droplets can either be trapped stably in the docks or be released because deformed non-frozen aqueous droplets turn spherical when frozen, and thus can become dislodged from the docks. Additionally, using this chamber and chip combination we are able to exchange immiscible phases and surfactants surrounding the frozen droplets. The materials and methods are inexpensive and easily accessible to microfluidics researchers, making this a simple addition to an existing microfluidic platform.

  11. Nanoencapsulation Improves Scavenging Capacity and Decreases Cytotoxicity of Silibinin and Pomegranate Oil Association.

    PubMed

    Marchiori, Marila C L; Rigon, Cristina; Copetti, Priscila M; Sagrillo, Michele R; Cruz, Letícia

    2017-06-02

    Silibinin (SB) and pomegranate oil (PO) present therapeutic potential due to antioxidant activity, but the biological performance of both bioactives is limited by their low aqueous solubility. To overcome this issue, the aim of the present investigation was to develop nanocapsule suspensions with PO as oil core for SB encapsulation, as well as assess their toxicity in vitro and radical scavenging activity. The nanocapsule suspensions were prepared by interfacial deposition of preformed polymer method. SB-loaded PO-based nanocapsules (SBNC) showed an average diameter of 157 ± 3 nm, homogenous size distribution, zeta potential of -14.1 ± 1.7 mV, pH of 5.6 ± 0.4 and SB content close to 100%. Similar results were obtained for the unloaded formulation (PONC). The nanocapsules controlled SB release at least 10 times as compared with free SB in methanolic solution. The SBNC scavenging capacity in vitro was statistically higher than free SB (p < 0.05). Cell viability in monocytes and lymphocytes was kept around 100% in the treatments with SBNC and PONC, while the SB and the PO caused a decrease around 30% at 50 μM (SB) and 724 μg/mL (PO). Protein carbonyls and DNA damage were minimized by SB and PO nanoencapsulation. Lipid peroxidation occurred in nanocapsule treatments regardless of the SB presence, which may be attributed to PO acting as substrate in reaction. The free compounds also caused lipid peroxidation. The results show that SBNC and PONC presented adequate physicochemical characteristics and low toxicity against human blood cells. Thereby, this novel nanocarrier may be a promising formulation for therapeutic applications.

  12. Trypanocidal action of tea tree oil (Melaleuca alternifolia) against Trypanosoma evansi in vitro and in vivo used mice as experimental model.

    PubMed

    Baldissera, Matheus D; Da Silva, Aleksandro S; Oliveira, Camila B; Santos, Roberto C V; Vaucher, Rodrigo A; Raffin, Renata P; Gomes, Patrícia; Dambros, Maria G C; Miletti, Luiz C; Boligon, Aline A; Athayde, Margareth L; Monteiro, Silvia G

    2014-06-01

    This study aimed to evaluate the Trypanosoma evansi susceptibility to tea tree oil (TTO - Melaleuca alternifolia) and tea tree oil nanocapsules (TTO nanocapsules) in vitro and in vivo tests. In vitro, we observed a mortality curve of trypomastigotes proportional to dose, i.e., the TTO and TTO nanocapsules have trypanocidal effect. Treatment with TTO in vivo was assessed in experiments (I and II). For Experiment I, T. evansi infected mice were treated with TTO and/or combinations of essential oil with chemotherapy (diminazene aceturate - D.A.). Treatment with TTO at a dose of 1mLkg(-1) was able to extend animal longevity, but had no curative efficacy. However, when TTO was combined with D.A. a disease curative efficacy of 100% for disease was observed, a much better result than the D.A. treatment (33.3%). In Experiment II, T. evansi infected mice were treated with TTO nanocapsules with doses of 0.3, 0.6 and 0.9mLkg(-1). Animals treated with 0.9mLkg(-1) showed higher longevity however without curative effect. Active compounds present in natural products, such as M. alternifolia, may potentiate the treatment of trypanosomosis when associated with other trypanocidal drugs. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Near-infrared fluorescent nanocapsules with reversible response to thermal/pH modulation for optical imaging.

    PubMed

    Chen, Yongping; Li, Xingde

    2011-12-12

    Polymeric near-infrared (NIR) fluorescent nanocapsules were developed, of which the fluorescence exhibited reversible response to local thermal/pH modulation. Our strategy was to use polymeric micelles made of temperature-sensitive Pluronic F-127 to encapsulate an amphiphilic NIR fluorescent dye-indocyanine green (ICG)-within the core and then cross-link the micelle corona by pH-sensitive poly(ethylenimine) (PEI). The size swelling/shrinking property of the micelles induced by temperature decrease/increase was used as a switch to control the fluorescence yield of the nanocapsules. It was found that the fluorescence yield significantly increased with the increase in temperature. The PEI cross-link made the fluorescence yield also sensitive to local pH change and enhanced intracellular delivery of the nanocapsules as well. Preliminary results suggest the NIR fluorescent probes could be potentially used as a contrast agent sensitive to local environment for translational optical imaging/sensing.

  14. 21 CFR 146.121 - Frozen concentrate for artificially sweetened lemonade.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices and Beverages § 146.121 Frozen concentrate for artificially sweetened lemonade... suitable dispersing ingredients serving the function of distributing the lemon oil throughout the food. It...

  15. 21 CFR 146.121 - Frozen concentrate for artificially sweetened lemonade.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices and Beverages § 146.121 Frozen concentrate for artificially sweetened lemonade... suitable dispersing ingredients serving the function of distributing the lemon oil throughout the food. It...

  16. Spray-dried powders containing tretinoin-loaded engineered lipid-core nanocapsules: development and photostability study.

    PubMed

    Marchiori, M C L; Ourique, A F; da Silva, C de B; Raffin, R P; Pohlmann, A R; Guterres, S S; Beck, R C R

    2012-03-01

    The influence of the spray-drying process on the ability of engineered lipid-core nanocapsules to protect tretinoin against UV degradation was evaluated. This approach represents a technological alternative to improve the microbiological stability, storage and transport properties of such formulations. Tretinoin-loaded lipid-core nanocapsules or tretinoin-loaded nanoemulsion were dispersed in lactose (10% w/v) and fed in the spray-drier to obtain a solid product (spray-dried powder containing tretinoin-loaded nanocapsules or nanoemulsion--SD-TTN-NCL or SD-TTN-NE, respectively). SD-TTN-NE showed a lower (p < or = 0.05) percentage of encapsulation (89 +/- 1%) compared to SD-TTN-NCL (94 +/- 2%). Redispersed SD-TTN-NCL and SD-TTN-NE showed z-average sizes of 204 +/- 2 nm and 251 +/- 9 nm, which were close to those of the original suspensions (220 +/- 3 nm and 239 +/- 14 nm, respectively). Similar percentage of photodegradation were determined for tretinoin loaded in nanocapsules (26.15 +/- 4.34%) or in the respective redispersed spray-dried powder (28.73 +/- 6.19 min) after 60 min of UVA radiation exposure (p > 0.05). Our experimental design showed for the first time that spray-dried lipid-core nanocapsules are able to protect tretinoin against UVA radiation, suggesting that the drying process did not alter the supramolecular structure of the lipid-core nanocapsules. Such powders are potential intermediate products for the development of nanomedicines containing tretinoin.

  17. Strong cation···π interactions promote the capture of metal ions within metal-seamed nanocapsule.

    PubMed

    Kumari, Harshita; Jin, Ping; Teat, Simon J; Barnes, Charles L; Dalgarno, Scott J; Atwood, Jerry L

    2014-12-10

    Thallium ions are transported to the interior of gallium-seamed pyrogallol[4]arene nanocapsules. In comparison to the capture of Cs ions, the extent of which depends on the type and position of the anion employed in the cesium salt, the enhanced strength of Tl···π vs Cs···π interactions facilitates permanent entrapment of Tl(+) ions on the capsule interior. "Stitching-up" the capsule seam with a tertiary metal (Zn, Rb, or K) affords new trimetallic nanocapsules in solid state.

  18. Protein changes in frozen fish.

    PubMed

    Sikorski, Z; Olley, J; Kostuch, S

    1976-09-01

    Storage of frozen fish brings about a decrease of extractability of myofibrillar proteins. There is also deterioration of the texture and functional properties of the flesh. In model systems, aggregation of myosin, actin, tropomyosin, and whole myofibrils have been described. These changes are caused by concurrent action of partial dehydration due to the freezing out of water, exposure of the proteins to inorganic salts which are concentrated in the remaining nonfrozen fluid, interactions with free fatty acids liberated from phospholipids and with lipid oxidation products, and cross-linking by formaldehyde produced in some species of fish as a result of enzymic decomposition of trimethylamine oxide. The extent of protein alterations increases with time and temperature of storage as well as with advanced disintegration of the tissues and intermixing of their components. The role played by the individual factors and the significance of different types of bonds, i.e., hydrophobic adherences, ionic bonds, and covalent cross-links in particular cases are not yet fully disclosed. Retardation of the deteriorative changes of proteins in frozen fish is possible by avoiding high storage temperatures and oxidation of lipids, removing hematin compounds and other constituents promoting cross-linking reactions, and by adding cryoprotectors like sugars, several organic acids, amino acids, or peptides.

  19. Gold nanorod-covered kanamycin-loaded hollow SiO2 (HSKAu(rod)) nanocapsules for drug delivery and photothermal therapy on bacteria.

    PubMed

    Hu, Bo; Zhang, Li-Pei; Chen, Xu-Wei; Wang, Jian-Hua

    2013-01-07

    A hybrid bactericidal material, gold nanorod-covered kanamycin-loaded hollow SiO(2) (HSKAu(rod)) nanocapsules, is constructed. The hybrid material combines the features of a chemical drug with photothermal physical sterilization which decreases the dosage of broad-spectrum antibiotic and the physical damage of biological systems. Hollow SiO(2) nanocapsules are used as carriers for drug delivery. The nanocapsules load a model drug, kanamycin, and are covered with gold nanorods to avoid drug leakage and realize photothermal treatment. The sterilizing effect on the bacterial strain is investigated by incubating E. coli BL21 with the hybrid nanocapsules and irradiating under near-infrared light (NIR) for 20 min. A bactericidal effect, i.e., a sterilizing rate of 53.47%, is achieved for the HSKAu(rod) nanocapsules under NIR irradiation, with respect to a net sum sterilizing rate of 34.49% for the individual components of the HSKAu(rod) nanocapsules, e.g., carrier nanocapsules, chemical sterilization of kanamycin and physical sterilization due to the gold nanorods under NIR irradiation. It is demonstrated that the combination of chemical drug and physical sterilization results in an obvious synergistic effect and makes the sterilization more effective. This novel hybrid has great potential as an adjuvant therapeutic alternative material for sterilization or even for the control of disease.

  20. Gold nanorod-covered kanamycin-loaded hollow SiO2 (HSKAurod) nanocapsules for drug delivery and photothermal therapy on bacteria

    NASA Astrophysics Data System (ADS)

    Hu, Bo; Zhang, Li-Pei; Chen, Xu-Wei; Wang, Jian-Hua

    2012-12-01

    A hybrid bactericidal material, gold nanorod-covered kanamycin-loaded hollow SiO2 (HSKAurod) nanocapsules, is constructed. The hybrid material combines the features of a chemical drug with photothermal physical sterilization which decreases the dosage of broad-spectrum antibiotic and the physical damage of biological systems. Hollow SiO2 nanocapsules are used as carriers for drug delivery. The nanocapsules load a model drug, kanamycin, and are covered with gold nanorods to avoid drug leakage and realize photothermal treatment. The sterilizing effect on the bacterial strain is investigated by incubating E. coli BL21 with the hybrid nanocapsules and irradiating under near-infrared light (NIR) for 20 min. A bactericidal effect, i.e., a sterilizing rate of 53.47%, is achieved for the HSKAurod nanocapsules under NIR irradiation, with respect to a net sum sterilizing rate of 34.49% for the individual components of the HSKAurod nanocapsules, e.g., carrier nanocapsules, chemical sterilization of kanamycin and physical sterilization due to the gold nanorods under NIR irradiation. It is demonstrated that the combination of chemical drug and physical sterilization results in an obvious synergistic effect and makes the sterilization more effective. This novel hybrid has great potential as an adjuvant therapeutic alternative material for sterilization or even for the control of disease.

  1. Decoupling the effects of the size, wall thickness, and porosity of curcumin-loaded chitosan nanocapsules on their anticancer efficacy: size is the winner.

    PubMed

    Goethals, Emma C; Elbaz, Abdulkareem; Lopata, Andreas L; Bhargava, Suresh K; Bansal, Vipul

    2013-01-15

    Polymer nanocapsules have gained an important place as drug delivery vehicles for a myriad of biomedical applications. However, the influence of nanocapsule size, wall thickness, and porosity toward controlling the drug delivery efficiency of nanocapsular systems is not well understood. We report a facile template-mediated approach for the development of near monodispersed chitosan nanocapsules of different sizes, wall thicknesses, and porosities in a controllable manner. The ability of this approach to finely tune the structural characteristics of chitosan nanocapsules enabled us to systematically investigate the influence of capsule size, wall thickness, and porosity on their efficiency as drug delivery vehicles against mouse mastocytoma cells after loading them with curcumin, a natural lipophilic anticancer drug. This study establishes an important finding in the field of nanocapsule-based drug delivery systems that although several structural characteristics of a nanocapsule might be responsible in influencing their efficiency as a chemotherapeutic carrier, the size of the nanocapsules is likely to play the most important role in dictating the chemotherapeutic efficiency of such systems.

  2. Efficacy of Lychnopholide Polymeric Nanocapsules after Oral and Intravenous Administration in Murine Experimental Chagas Disease.

    PubMed

    de Mello, Carlos Geraldo Campos; Branquinho, Renata Tupinambá; Oliveira, Maykon Tavares; Milagre, Matheus Marques; Saúde-Guimarães, Dênia Antunes; Mosqueira, Vanessa Carla Furtado; Lana, Marta de

    2016-09-01

    The etiological treatment of Chagas disease remains neglected. The compounds available show several limitations, mainly during the chronic phase. Lychnopholide encapsulated in polymeric nanocapsules (LYC-NC) was efficacious in mice infected with Trypanosoma cruzi and treated by intravenous administration during the acute phase (AP). As the oral route is preferred for treatment of chronic infections, such as Chagas disease, this study evaluated the use of oral LYC-NC in the AP and also compared it with LYC-NC administered to mice by the oral and intravenous routes during the chronic phase (CP). The therapeutic efficacy was evaluated by fresh blood examination, hemoculture, PCR, and enzyme-linked immunosorbent assay (ELISA). The cure rates in the AP and CP were 62.5% and 55.6%, respectively, upon oral administration of LYC-poly(d,l-lactide)-polyethylene glycol nanocapsules (LYC-PLA-PEG-NC) and 57.0% and 30.0%, respectively, with LYC-poly-ε-caprolactone nanocapsules (LYC-PCL-NC). These cure rates were significantly higher than that of free LYC, which did not cure any animals. LYC-NC formulations administered orally during the AP showed cure rates similar to that of benznidazole, but only LYC-NC cured mice in the CP. Similar results were achieved with intravenous treatment during the CP. The higher cure rates obtained with LYC loaded in PLA-PEG-NC may be due to the smaller particle size of these NC and the presence of PEG, which influence tissue diffusion and the controlled release of LYC. Furthermore, PLA-PEG-NC may improve the stability of the drug in the gastrointestinal tract. This work is the first report of cure of experimental Chagas disease via oral administration during the CP. These findings represent a new and important perspective for oral treatment of Chagas disease. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  3. Efficacy of Lychnopholide Polymeric Nanocapsules after Oral and Intravenous Administration in Murine Experimental Chagas Disease

    PubMed Central

    de Mello, Carlos Geraldo Campos; Branquinho, Renata Tupinambá; Oliveira, Maykon Tavares; Milagre, Matheus Marques; Saúde-Guimarães, Dênia Antunes; Mosqueira, Vanessa Carla Furtado

    2016-01-01

    The etiological treatment of Chagas disease remains neglected. The compounds available show several limitations, mainly during the chronic phase. Lychnopholide encapsulated in polymeric nanocapsules (LYC-NC) was efficacious in mice infected with Trypanosoma cruzi and treated by intravenous administration during the acute phase (AP). As the oral route is preferred for treatment of chronic infections, such as Chagas disease, this study evaluated the use of oral LYC-NC in the AP and also compared it with LYC-NC administered to mice by the oral and intravenous routes during the chronic phase (CP). The therapeutic efficacy was evaluated by fresh blood examination, hemoculture, PCR, and enzyme-linked immunosorbent assay (ELISA). The cure rates in the AP and CP were 62.5% and 55.6%, respectively, upon oral administration of LYC–poly(d,l-lactide)–polyethylene glycol nanocapsules (LYC-PLA-PEG-NC) and 57.0% and 30.0%, respectively, with LYC–poly-ε-caprolactone nanocapsules (LYC-PCL-NC). These cure rates were significantly higher than that of free LYC, which did not cure any animals. LYC-NC formulations administered orally during the AP showed cure rates similar to that of benznidazole, but only LYC-NC cured mice in the CP. Similar results were achieved with intravenous treatment during the CP. The higher cure rates obtained with LYC loaded in PLA-PEG-NC may be due to the smaller particle size of these NC and the presence of PEG, which influence tissue diffusion and the controlled release of LYC. Furthermore, PLA-PEG-NC may improve the stability of the drug in the gastrointestinal tract. This work is the first report of cure of experimental Chagas disease via oral administration during the CP. These findings represent a new and important perspective for oral treatment of Chagas disease. PMID:27324760

  4. Mono-dispersed Functional Polymeric Nanocapsules with Multi-lacuna via Soapless Microemulsion Polymerization with Spindle-like α-Fe2O3 Nanoparticles as Templates

    NASA Astrophysics Data System (ADS)

    Liu, Guangfeng; Liu, Peng

    2009-03-01

    The mono-dispersed crosslinked polymeric multi-lacuna nanocapsules (CP(St-OA) nanocapsules) about 40 nm with carboxylic groups on their inner and outer surfaces were fabricated in the present work. The small conglomerations of the oleic acid modified spindle-like α-Fe2O3 nanoparticles (OA-Fe2O3) were encapsulated in the facile microemulsion polymerization with styrene (St) as monomer and divinyl benzene (DVB) as crosslinker. Then the templates, small conglomerations of OA-Fe2O3, were etched with HCl in tetrahydrofuran (THF). The surface carboxylic groups of the crosslinked polymeric multi-lacuna nanocapsules were validated by the Zeta potential analysis.

  5. Dispersion of carbon nanocapsules by using highly aspect-ratio clays

    NASA Astrophysics Data System (ADS)

    Lan, Yi-Fen; Cheng, Szu-Chiao

    2012-04-01

    The poor solubility of zero-dimensional nanomaterials can be greatly improved by using two-dimensional nanomaterials as a dispersant. The solubility of nano-spherical carbon nanocapsules (CNCs) was improved by using platelet-like clays. Three clays including synthetic fluorinated mica (Mica), sodium montmorillonite, and synthetic smectite were selected for assist CNCs to disperse in several solvents. The aspect ratios of clays were calculated by dimension over thickness, and the results revealed that the aspect ratio is the dominated factor to control the dispersion of CNCs in solvents.

  6. Self-Assembly of Uranyl-Peroxide Nanocapsules in Basic Peroxidic Environments.

    PubMed

    Miró, Pere; Vlaisavljevich, Bess; Gil, Adria; Burns, Peter C; Nyman, May; Bo, Carles

    2016-06-13

    A wide range of uranyl-peroxide nanocapsules have been synthesized using very simple reactants in basic media; however, little is known about the process to form these species. We have performed a density functional theory study of the speciation of the uranyl ions under different experimental conditions and explored the formation of dimeric species via a ligand exchange mechanism. We shed some light onto the importance of the excess of peroxide and alkali counterions as a thermodynamic driving force towards the formation of larger uranyl-peroxide species.

  7. Interpreting Neutron Probe Readings In Frozen Soil

    Treesearch

    Richard S. Sartz

    1969-01-01

    Several factors associated with soil freezing complicate the interpretation of neutron probe readings in frozen soil. Temperature is unimportant, but the effect of vertical resolution must be considered. Because of the possibility of both gains and losses of water at the same depth during a period of measurement, interpreting changes in the water content of frozen...

  8. Pine pollens frozen five years produce seed

    Treesearch

    R.Z. Callaham; R.J. Steinhoff

    1966-01-01

    Deep-freezing of pine pollen offers a means of prolonging its storage life. Early work showed that pollen could be frozen without losing its viability. A study was started in 1958 at the Institute of Forest Genetics at Placerville to determine how long frozen pollen of several pines would remain viable. This paper reports in vitro germination and in vivo seed...

  9. A review on frozen shoulder.

    PubMed

    Wong, P L; Tan, H C

    2010-09-01

    Of all the joints in the human body, the shoulder has the greatest range of motion. This allows complex movements and functions to be carried out, and is of vital importance to the activities of daily living and work. Any restriction or pain that involves the joint puts a huge amount of strain on patients, especially those who are in their most productive years of life. Frozen shoulder, a frequently encountered disorder of the shoulder, has been well recognised since the early 1900s. Although benign, it has great impact on the quality of life of patients. This article aims to provide an overview of the nature and the widely accepted management of this condition based on other studies.

  10. Testing the frozen flow approximation

    NASA Technical Reports Server (NTRS)

    Lucchin, Francesco; Matarrese, Sabino; Melott, Adrian L.; Moscardini, Lauro

    1993-01-01

    We investigate the accuracy of the frozen-flow approximation (FFA), recently proposed by Matarrese, et al. (1992), for following the nonlinear evolution of cosmological density fluctuations under gravitational instability. We compare a number of statistics between results of the FFA and n-body simulations, including those used by Melott, Pellman & Shandarin (1993) to test the Zel'dovich approximation. The FFA performs reasonably well in a statistical sense, e.g. in reproducing the counts-in-cell distribution, at small scales, but it does poorly in the crosscorrelation with n-body which means it is generally not moving mass to the right place, especially in models with high small-scale power.

  11. The mechanism of CO2 hydration: a porous metal oxide nanocapsule catalyst can mimic the biological carbonic anhydrase role.

    PubMed

    Bandeira, Nuno A G; Garai, Somenath; Müller, Achim; Bo, Carles

    2015-11-04

    The mechanism for the hydration of CO2 within a Keplerate nanocapsule is presented. A network of hydrogen bonds across the water layers in the first metal coordination sphere facilitates the proton abstraction and nucleophilic addition of water. The highly acidic properties of the polyoxometalate cluster are crucial for explaining the catalysed hydration.

  12. Enhanced in vivo therapeutic efficacy of plitidepsin-loaded nanocapsules decorated with a new poly-aminoacid-PEG derivative.

    PubMed

    Lollo, Giovanna; Hervella, Pablo; Calvo, Pilar; Avilés, Pablo; Guillén, Maria Jose; Garcia-Fuentes, Marcos; Alonso, Maria José; Torres, Dolores

    2015-04-10

    The focus of this study is to disclose a new delivery carrier intended to improve the pharmacokinetic characteristics of the anticancer drug plitidepsin and to favor its accumulation within the tumor. These nanocarriers named as nanocapsules, consist of an oily core surrounded by a highly PEGylated polyglutamic acid (PGA-PEG) shell loaded with plitidepsin. They showed a size of around 190 nm, a zeta potential of -24 mV and were able to encapsulate a high percentage (85%) of plitidepsin. In vivo studies, following intravenous injection in healthy mice, indicated that the encapsulation of the drug within PGA-PEG nanocapsules led to an important increase in its area under the curve (AUC) which is related to the important decrease of the clearance, as compared to the values observed for the drug dissolved in a Cremophor(®) EL solution. This improvement of the pharmacokinetic profile of the encapsulated plitidepsin was accompanied by a high increase (2.5-fold) of the maximum tolerated dose (MTD) in comparison to that of plitidepsin Cremophor(®) EL solution. The efficacy study performed in a xenograft tumor mice model evidenced the capacity of PGA-PEG nanocapsules to significantly reduce tumor growth. These promising results highlight the potential of PGA-PEG nanocapsules as an effective drug delivery system for cancer therapy. Copyright © 2015. Published by Elsevier B.V.

  13. PEGylated polypeptide lipid nanocapsules to enhance the anticancer efficacy of erlotinib in non-small cell lung cancer.

    PubMed

    Kim, Jeonghwan; Ramasamy, Thiruganesh; Choi, Ju Yeon; Kim, Ssang Tae; Youn, Yu Seok; Choi, Han-Gon; Yong, Chul Soon; Kim, Jong Oh

    2017-02-01

    In this study, a core-shell type polypeptide-based lipid nanocapsule was developed to enhance anticancer efficacy of erlotinib in non-small cell lung cancers. Mean particle size of PEGylated polypeptide-lipid nanocapsules (PLN) for erlotinib (ERL) delivery was ∼200nm with an effective surface charge of -20mV. Protective PEGylated polypeptide layer acted as a molecular fence and effectively controlled the diffusion of erlotinib from the lipid nanocapsule core, whereas pH-responsiveness of poly(L-aspartic acid) accelerated the release of erlotinib in acidic conditions. Blank lipid nanocapsules showed excellent biocompatibility. ERL-loaded PLN (ERL-PLN) showed dose-dependent cytotoxicity in NCI-H358 and HCC-827 lung cancer cells. ERL-PLN treatment resulted in a superior tumor regression profile in a xenograft tumor model, compared to free ERL and control, suggesting high therapeutic efficacy. ERL-PLN-treated mice showed 5- and 2-fold smaller tumor volume compared to control and free ERL groups, respectively. Based on these results, PLN provide a promising drug delivery approach for lung cancer therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Ultrasound-induced mild hyperthermia improves the anticancer efficacy of both Taxol® and paclitaxel-loaded nanocapsules.

    PubMed

    Boissenot, Tanguy; Bordat, Alexandre; Larrat, Benoît; Varna, Mariana; Chacun, Hélène; Paci, Angelo; Poinsignon, Vianney; Fattal, Elias; Tsapis, Nicolas

    2017-10-28

    We study the influence of ultrasound on paclitaxel-loaded nanocapsules in vitro and in vivo. These nanocapsules possess a shell of poly(dl-lactide-co-glycolide)-poly(ethylene glycol) (PLGA-PEG) and a liquid core of perfluorooctyl bromide (PFOB). In vitro experiments show that mechanical effects such as cavitation are negligible for nanocapsules due to their small size and thick and rigid shell. As the mechanical effects were unable to increase paclitaxel delivery, we focused on the thermal effects of ultrasound in the in vivo studies. A focused ultrasound sequence was therefore optimized in vivo under magnetic resonance imaging guidance to obtain localized mild hyperthermia with high acoustic pressure. Ultrasound-induced mild hyperthermia (41-43°C) was then tested in vivo in a subcutaneous CT-26 colon cancer murine model. As hyperthermia is applied, an inhibition of tumor growth for both paclitaxel-loaded nanocapsules and the commercial formulation of paclitaxel, namely Taxol® have been observed (p<0.05). Ultrasound-induced mild hyperthermia at high acoustic pressure appears as an interesting strategy to enhance cytotoxic efficacy locally. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Mucoadhesive Amphiphilic Methacrylic Copolymer-Functionalized Poly(ε-caprolactone) Nanocapsules for Nose-to-Brain Delivery of Olanzapine.

    PubMed

    Fonseca, Francisco N; Betti, Andresa H; Carvalho, Flávia C; Gremião, Maria P D; Dimer, Frantiescoli A; Guterres, Sílvia S; Tebaldi, Marli L; Rates, Stela M K; Pohlmann, Adriana R

    2015-08-01

    Nose-to-brain drug delivery has been proposed to overcome the low absorption of drugs in central nervous system due to the absence of brain-blood barrier in the olfactory nerve pathway. However, the presence of a mucus layer and quick clearance limit the use of this route. Herein, amphiphilic methacrylic copolymer-functionalized poly(ε-caprolactone) nanocapsules were proposed as a mucoadhesive system to deliver olanzapine after intranasal administration. In vitro evaluations showed that these nanocapsules were able to interact with mucin (up to 17% of increment in particle size and 30% of reduction of particle concentration) and nasal mucosa (2-fold higher force for detaching), as well as to increase the retention of olanzapine (about 40%) on the nasal mucosa after continuous wash. The olanzapine-loaded amphiphilic methacrylic copolymer-functionalized PCL nanocapsules enhanced the amount of drug in the brain of rats (1.5-fold higher compared to the drug solution). In accordance with this finding, this formulation improved the prepulse inhibition impairment induced by apomorphine, which is considered as an operational measure of pre-attentive sensorimotor gating impairment present in schizophrenia. Besides, nanoencapsulated olanzapine did not affect the nasal mucosa integrity after repeated doses. These data evidenced that the designed nanocapsules are a promising mucoadhesive system for nose-to-brain delivery of drugs.

  16. Releasable layer-by-layer assembly of stabilized lipid nanocapsules on microneedles for enhanced transcutaneous vaccine delivery.

    PubMed

    DeMuth, Peter C; Moon, James J; Suh, Heikyung; Hammond, Paula T; Irvine, Darrell J

    2012-09-25

    Here we introduce a new approach for transcutaneous drug delivery, using microneedles coated with stabilized lipid nanocapsules, for delivery of a model vaccine formulation. Poly(lactide-co-glycolide) microneedle arrays were coated with multilayer films via layer-by-layer assembly of a biodegradable cationic poly(β-amino ester) (PBAE) and negatively charged interbilayer-cross-linked multilamellar lipid vesicles (ICMVs). To test the potential of these nanocapsule-coated microneedles for vaccine delivery, we loaded ICMVs with a protein antigen and the molecular adjuvant monophosphoryl lipid A. Following application of microneedle arrays to the skin of mice for 5 min, (PBAE/ICMV) films were rapidly transferred from microneedle surfaces into the cutaneous tissue and remained in the skin following removal of the microneedle arrays. Multilayer films implanted in the skin dispersed ICMV cargos in the treated tissue over the course of 24 h in vivo, allowing for uptake of the lipid nanocapsules by antigen presenting cells in the local tissue and triggering their activation in situ. Microneedle-mediated transcutaneous vaccination with ICMV-carrying multilayers promoted robust antigen-specific humoral immune responses with a balanced generation of multiple IgG isotypes, whereas bolus delivery of soluble or vesicle-loaded antigen via intradermal injection or transcutaneous vaccination with microneedles encapsulating soluble protein elicited weak, IgG(1)-biased humoral immune responses. These results highlight the potential of lipid nanocapsules delivered by microneedles as a promising platform for noninvasive vaccine delivery applications.

  17. A chromium nitride/carbon nitride containing graphitic carbon nanocapsule hybrid as a Pt-free electrocatalyst for oxygen reduction.

    PubMed

    Zhao, Lu; Wang, Lei; Yu, Peng; Zhao, Dongdong; Tian, Chungui; Feng, He; Ma, Jing; Fu, Honggang

    2015-08-11

    Chromium nitride nanoparticles supported on graphitic carbon nanocapsules containing carbon nitride (CrN/GC) have been synthesized by a solvothermal-assisted ion-exchange route. As a Pt-free catalyst, the CrN/GC hybrid exhibits superior activity, stability, methanol immunity and a dominant 4-electron pathway towards oxygen reduction reaction.

  18. Structural alteration of the metal-organic pyrogallol[4]arene nano-capsule motif by incorporation of large metal centres.

    PubMed

    Jin, Ping; Kumari, Harshita; Kennedy, Stuart; Barnes, Charles L; Teat, Simon J; Dalgarno, Scott J; Atwood, Jerry L

    2014-05-04

    Addition of cadmium(II) nitrate to gallium-coordinated metal-organic C-alkylpyrogallol[4]arene nano-capsules affords a variation of the near spherical hexamer motif, structural changes in which are induced by the markedly different nature of the secondary incorporated metal.

  19. Template-Free Synthesis of Hollow/Porous Organosilica-Fe3O4 Hybrid Nanocapsules toward Magnetic Resonance Imaging-Guided High-Intensity Focused Ultrasound Therapy.

    PubMed

    Ma, Ming; Yan, Fei; Yao, Minghua; Wei, Zijun; Zhou, Dongliang; Yao, Heliang; Zheng, Hairong; Chen, Hangrong; Shi, Jianlin

    2016-11-09

    Entirely differing from the common templating-based multistep strategy for fabricating multifunctional hollow mesoporous silica nanoparticles (HMSN), a facile and template-free synthetic strategy has been established to construct a unique hollow/mesoporous organosilica nanocapsule (OSNC) concurrently encapsulating both isopentyl acetate (PeA) liquid and superparamagnetic iron oxides inside (denoted as PeA@OSNC). This novel material exhibits ultrasmall and uniform particle size (∼82 nm), high surface area (∼534 m(2)·g(-1)), and excellent colloidal stability in aqueous solution. The oil-phase PeA with relatively low boiling point (142 °C) and high volatility not only plays a crucial role in formation of a large hollow cavity from the viewpoint of structural design but also enables the PeA@OSNC to act as an efficient enhancement agent in high-intensity focused ultrasound (HIFU) therapy. Moreover, the unique satellite-like distribution of Fe3O4 nanoparticles (NP) on the organosilica shell offered excellent magnetic resonance imaging (MRI) contrast capability of PeA@OSNC in vitro and in vivo. More importantly, such a novel theranostic agent has favorable biosafety, which is very promising for future clinical application in MRI-guided HIFU therapy.

  20. Nanostructured cinnamon oil has the potential to control Rhipicephalus microplus ticks on cattle.

    PubMed

    Dos Santos, Daiane S; Boito, Jhonatan P; Santos, Roberto C V; Quatrin, Priscilla M; Ourique, Aline Ferreira; Dos Reis, João H; Gebert, Roger R; Glombowsky, Patrícia; Klauck, Vanderlei; Boligon, Aline A; Baldissera, Matheus D; Da Silva, Aleksandro S

    2017-08-29

    The aim of this study was to evaluate the capacity of pure and nanostructured cinnamon oil to control the infestation and reproductive efficiency of Rhipicephalus microplus on dairy cows. In vitro (stage I)-engorged female ticks were immersed in concentrations of 1.0, 5.0 and 10% of cinnamon oil on its pure form, and 0.5, 1.0, and 5.0% of the nanostructured form. 10% cinnamon oil (pure form) showed 100% efficacy, whereas concentrations of 1 and 5% were 62 and 97% efficacious, respectively. Nanocapsules and nanoemulsions containing cinnamon oil at 5% showed 95 and 97% efficacy, respectively. In vivo (stage II)-16 naturally tick-infested cows were divided into four groups of four animals each: Group A was composed of dairy cows sprayed with Triton (control); Group B was composed of dairy cows sprayed with cinnamon oil in its pure form (5%), whereas groups C and D were composed of dairy cows sprayed with nanocapsules and nanoemulsions, respectively, containing cinnamon oil at 0.5%. The ticks on each animal were counted on days 0, 1, 4 and 20 after spraying. Animals sprayed with pure and nanoencapsulated cinnamon oil carried significantly fewer ticks on days 1 and 4 post-treatment and were free of ticks on day 20 post-treatment. Ticks collected from these dairy cows (24 h after application) had impaired oviposition and larval inhibition, resulting in 90.5 and 100% efficacy when using pure and nanocapsules, respectively. In conclusion, the pure and nanostructured forms of cinnamon oil interfered with tick reproduction, whereas a significant acaricidal effect was found when applied onto cattle.

  1. Development of lycopene-loaded lipid-core nanocapsules: physicochemical characterization and stability study

    NASA Astrophysics Data System (ADS)

    dos Santos, Priscilla Pereira; Paese, Karina; Guterres, Silvia Stanisçuaski; Pohlmann, Adriana Raffin; Costa, Tania Hass; Jablonski, André; Flôres, Simone Hickmann; Rios, Alessandro de Oliveira

    2015-02-01

    The objective of this study was to develop lycopene-loaded lipid-core nanocapsules (Lyc-LNCs) by the interfacial deposition of preformed poly(ɛ-caprolactone) (PCL). Lyc extract (93.9 %) was obtained from tomatoes, and the organic phase was prepared with polymer (PCL), caprylic/capric triglycerides, sorbitan monostearate, and Lyc in a mixture of acetone and ethanol under magnetic stirring at 40 °C. The organic phase was injected into an aqueous phase containing polysorbate 80, and the suspension was concentrated under reduced pressure. The formulation with a Lyc concentration of 85 µg/mL was characterized in terms of size distribution, zeta potential, encapsulation efficiency, pH, viscosity, and color. The Lyc-LNC formulation presented stable values for the z-average (193 ± 4.7 nm) and zeta potential (-11.5 ± 0.40 mV). Despite the lower pH, Lyc content, and color change of the suspension, the nanocapsules showed satisfactory stability, presenting around 50 % Lyc content after 14 days of storage at room temperature (25 °C).

  2. Specific Elimination of Latently HIV-1 Infected Cells Using HIV-1 Protease-Sensitive Toxin Nanocapsules.

    PubMed

    Wen, Jing; Yan, Ming; Liu, Yang; Li, Jie; Xie, Yiming; Lu, Yunfeng; Kamata, Masakazu; Chen, Irvin S Y

    2016-01-01

    Anti-retroviral drugs suppress HIV-1 plasma viremia to undetectable levels; however, latent HIV-1 persists in reservoirs within HIV-1-infected patients. The silent provirus can be activated through the use of drugs, including protein kinase C activators and histone deacetylase inhibitors. This "shock" approach is then followed by "kill" of the producing cells either through direct HIV-1-induced cell death or natural immune mechanisms. However, these mechanisms are relatively slow and effectiveness is unclear. Here, we develop an approach to specifically target and kill cells that are activated early in the process of virus production. We utilize a novel nanocapsule technology whereby the ricin A chain is encapsulated in an inactive form within a polymer shell. Specificity for release of the ricin A toxin is conferred by peptide crosslinkers that are sensitive to cleavage by HIV-1 protease. By using well-established latent infection models, J-Lat and U1 cells, we demonstrate that only within an HIV-1-producing cell expressing functional HIV-1 protease will the nanocapsule release its ricin A cargo, shutting down viral and cellular protein synthesis, and ultimately leading to rapid death of the producer cell. Thus, we provide proof of principle for a novel technology to kill HIV-1-producing cells without effects on non-target cells.

  3. Polymeric nanocapsules with up-converting nanocrystals cargo make ideal fluorescent bioprobes

    PubMed Central

    Bazylińska, U.; Wawrzyńczyk, D.; Kulbacka, J.; Frąckowiak, R.; Cichy, B.; Bednarkiewicz, A.; Samoć, M.; Wilk, K. A.

    2016-01-01

    An innovative approach for up-converting nanoparticles adaptation for bio-related and theranostic applications is presented. We have successfully encapsulated multiple, ~8 nm in size NaYF4 nanoparticles inside the polymeric nanocarriers with average size of ~150 nm. The initial coating of nanoparticles surfaces was preserved due to the hydrophobic environment inside the nanocapsules, and thus no single nanoparticle surface functionalization was necessary. The selection of biodegradable and sugar-based polyelectrolyte shells ensured biocompatibility of the nanostructures, while the choice of Tm3+ and Yb3+ NaYF4 nanoparticles co-doping allowed for near-infrared to near-infrared bioimaging of healthy and cancerous cell lines. The protective role of organic shell resulted in not only preserved high up-converted emission intensity and long luminescence lifetimes, without quenching from water environment, but also ensured low cytotoxicity and high cellular uptake of the engineered nanocapsules. The multifunctionality of the proposed nanocarriers is a consequence of both the organic exterior part that is accessible for conjugation with biologically important molecules, and the hydrophobic interior, which in future application may be used as a container for co-encapsulation of inorganic nanoparticles and anticancer drug cargo. PMID:27406954

  4. Facile Directed Assembly of Hollow Polymer Nanocapsules within Spontaneously Formed Catanionic Surfactant Vesicles

    SciTech Connect

    Kim, Mariya D.; Dergunov, Sergey; Richter, Andrew; Durbin, Jeffrey; Shmakov, Sergey; Jia, Ying; Kenbeilova, Saltanat; Orazbekuly, Yerbolat; Kengpeiil, Aigerim; Lindner, Erno; Pingali, Sai Venkatesh; Urban, Volker S; Weigand, Steven; Pinkhassik, Eugene

    2014-01-01

    Surfactant vesicles containing monomers in the interior of the bilayer were used to template hollow polymer nanocapsules. This study investigated the formation of surfactant/monomer assemblies by two loading methods, concurrent loading and diffusion loading. The assembly process and the resulting aggregates were investigated with dynamic light scattering, small angle neutron scattering, and small-angle X-ray scattering. Acrylic monomers formed vesicles with a mixture of cationic and anionic surfactants in a broad range of surfactant ratios. Regions with predominant formation of vesicles were broader for compositions containing acrylic monomers compared with blank surfactants. This observation supports the stabilization of the vesicular structure by acrylic monomers. Diffusion loading produced monomer-loaded vesicles unless vesicles were composed from surfactants at the ratios close to the boundary of a vesicular phase region on a phase diagram. Both concurrent-loaded and diffusion-loaded surfactant/monomer vesicles produced hollow polymer nanocapsules upon the polymerization of monomers in the bilayer followed by removal of surfactant scaffolds.

  5. Oral fondaparinux: use of lipid nanocapsules as nanocarriers and in vivo pharmacokinetic study

    PubMed Central

    Ramadan, Alyaa; Lagarce, Frederic; Tessier-Marteau, Anne; Thomas, Olivier; Legras, Pierre; Macchi, Laurent; Saulnier, Patrick; Benoit, Jean Pierre

    2011-01-01

    Oral anticoagulant therapy could be advanced using lipid-based nanoparticulate systems. This study examined lipid nanocapsules for their oral absorption potential as the first step in developing oral fondaparinux (Fp) novel carriers. Using phase inversion method and cationic surfactants such as hexadecyltrimethyl ammonium bromide (CTAB) or stearylamine (SA), cationic lipid nanocapsules (cLNCs), loaded with Fp on their surface, were prepared and characterized (zeta potential, size and Fp association efficiency and content). In vivo studies were conducted after single oral increasing doses of Fp-loaded cLNCs (0.5 to 5 mg/kg of Fp) in rats and the concentration of Fp in the plasma was measured by anti-factor Xa activity assay. The monodisperse, (~50 nm), positively charged Fp-cLNCs with high drug loadings demonstrated linear pharmacokinetic profiles of the drug with an increased oral absolute bioavailability (up to ~21%) compatible with therapeutic anticoagulant effect (>0.2 μg/mL). PMID:22162653

  6. Lipid nanocapsules as a new delivery system in copepods: Toxicity studies and optical imaging.

    PubMed

    Stancheva, Stefka; Souissi, Anissa; Ibrahim, Ali; Barras, Alexandre; Spriet, Corentin; Souissi, Sami; Boukherroub, Rabah

    2015-11-01

    In this paper, we investigated the potential of lipid nanocapsules (LNCs) as a delivery system of small hydrophobic molecules, polycyclic aromatic hydrocarbons (PAHs) - pyrene, fluoranthene, phenanthrene, in the copepod Acartia tonsa. The LNCs were produced by a phase inversion process with a nominal size of 50 nm. These nanocapsules were obtained without organic solvent and with pharmaceutically acceptable excipients. The PAHs-LNCs displayed a stable monodisperse size distribution and a good stability in sea water for 7 days. By using fluorescent LNCs, it was possible to evidence LNCs ingestion by the copepods using confocal laser scanning microscopy. While blank LNCs are not toxic to copepods at tested concentrations, PAH-loaded LNCs were found to be very toxic on A. tonsa with a high mortality rate reaching 95% after 72 h exposure to 200 nM pyrene-loaded LNCs. On the other hand, when acetone is used to dissolve an equivalent concentration of PAHs in sea water, the copepod mortality is 10 times lower than using LNCs as nano-delivery system. This confirms the efficiency of using LNCs to deliver molecules directly in the gut or copepod carapace. The small size and non toxicity of these delivery nano-systems make them suitable for drug delivery to copepods.

  7. Ultrastable Liquid-Liquid Interface as Viable Route for Controlled Deposition of Biodegradable Polymer Nanocapsules.

    PubMed

    Vecchione, Raffaele; Iaccarino, Giulia; Bianchini, Paolo; Marotta, Roberto; D'autilia, Francesca; Quagliariello, Vincenzo; Diaspro, Alberto; Netti, Paolo A

    2016-06-01

    Liquid-liquid interfaces are highly dynamic and characterized by an elevated interfacial tension as compared to solid-liquid interfaces. Therefore, they are gaining an increasing interest as viable templates for ordered assembly of molecules and nanoparticles. However, liquid-liquid interfaces are more difficult to handle compared to solid-liquid interfaces; their intrinsic instability may affect the assembly process, especially in the case of multiple deposition. Indeed, some attempts have been made in the deposition of polymer multilayers at liquid-liquid interfaces, but with limited control over size and stability. This study reports on the preparation of an ultrastable liquid-liquid interface based on an O/W secondary miniemulsion and its possible use as a template for the self-assembly of polymeric multilayer nanocapsules. Such polymer nanocapsules are made of entirely biodegradable materials, with highly controlled size-well under 200 nm-and multi-compartment and multifunctional features enriching their field of application in drug delivery, as well as in other bionanotechnology fields.

  8. Specific Elimination of Latently HIV-1 Infected Cells Using HIV-1 Protease-Sensitive Toxin Nanocapsules

    PubMed Central

    Wen, Jing; Yan, Ming; Liu, Yang; Li, Jie; Xie, Yiming; Lu, Yunfeng; Kamata, Masakazu; Chen, Irvin S. Y.

    2016-01-01

    Anti-retroviral drugs suppress HIV-1 plasma viremia to undetectable levels; however, latent HIV-1 persists in reservoirs within HIV-1-infected patients. The silent provirus can be activated through the use of drugs, including protein kinase C activators and histone deacetylase inhibitors. This “shock” approach is then followed by “kill” of the producing cells either through direct HIV-1-induced cell death or natural immune mechanisms. However, these mechanisms are relatively slow and effectiveness is unclear. Here, we develop an approach to specifically target and kill cells that are activated early in the process of virus production. We utilize a novel nanocapsule technology whereby the ricin A chain is encapsulated in an inactive form within a polymer shell. Specificity for release of the ricin A toxin is conferred by peptide crosslinkers that are sensitive to cleavage by HIV-1 protease. By using well-established latent infection models, J-Lat and U1 cells, we demonstrate that only within an HIV-1-producing cell expressing functional HIV-1 protease will the nanocapsule release its ricin A cargo, shutting down viral and cellular protein synthesis, and ultimately leading to rapid death of the producer cell. Thus, we provide proof of principle for a novel technology to kill HIV-1-producing cells without effects on non-target cells. PMID:27049645

  9. Triple-Modal Imaging of Magnetically-Targeted Nanocapsules in Solid Tumours In Vivo.

    PubMed

    Bai, Jie; Wang, Julie T-W; Rubio, Noelia; Protti, Andrea; Heidari, Hamed; Elgogary, Riham; Southern, Paul; Al-Jamal, Wafa' T; Sosabowski, Jane; Shah, Ajay M; Bals, Sara; Pankhurst, Quentin A; Al-Jamal, Khuloud T

    2016-01-01

    Triple-modal imaging magnetic nanocapsules, encapsulating hydrophobic superparamagnetic iron oxide nanoparticles, are formulated and used to magnetically target solid tumours after intravenous administration in tumour-bearing mice. The engineered magnetic polymeric nanocapsules m-NCs are ~200 nm in size with negative Zeta potential and shown to be spherical in shape. The loading efficiency of superparamagnetic iron oxide nanoparticles in the m-NC was ~100%. Up to ~3- and ~2.2-fold increase in tumour uptake at 1 and 24 h was achieved, when a static magnetic field was applied to the tumour for 1 hour. m-NCs, with multiple imaging probes (e.g. indocyanine green, superparamagnetic iron oxide nanoparticles and indium-111), were capable of triple-modal imaging (fluorescence/magnetic resonance/nuclear imaging) in vivo. Using triple-modal imaging is to overcome the intrinsic limitations of single modality imaging and provides complementary information on the spatial distribution of the nanocarrier within the tumour. The significant findings of this study could open up new research perspectives in using novel magnetically-responsive nanomaterials in magnetic-drug targeting combined with multi-modal imaging.

  10. Iron-Loaded Magnetic Nanocapsules for pH-Triggered Drug Release and MRI Imaging

    PubMed Central

    2014-01-01

    Magnetic nanocapsules were synthesized for controlled drug release, magnetically assisted delivery, and MRI imaging. These magnetic nanocapsules, consisting of a stable iron nanocore and a mesoporous silica shell, were synthesized by controlled encapsulation of ellipsoidal hematite in silica, partial etching of the hematite core in acid, and reduction of the core by hydrogen. The iron core provided a high saturation magnetization and was stable against oxidation for at least 6 months in air and 1 month in aqueous solution. The hollow space between the iron core and mesoporous silica shell was used to load anticancer drug and a T1-weighted MRI contrast agent (Gd-DTPA). These multifunctional monodispersed magnetic “nanoeyes” were coated by multiple polyelectrolyte layers of biocompatible poly-l-lysine and sodium alginate to control the drug release as a function of pH. We studied pH-controlled release, magnetic hysteresis curves, and T1/T2 MRI contrast of the magnetic nanoeyes. They also served as MRI contrast agents with relaxivities of 8.6 mM–1 s–1 (r1) and 285 mM–1 s–1 (r2). PMID:24748722

  11. Polymeric nanocapsules with up-converting nanocrystals cargo make ideal fluorescent bioprobes

    NASA Astrophysics Data System (ADS)

    Bazylińska, U.; Wawrzyńczyk, D.; Kulbacka, J.; Frąckowiak, R.; Cichy, B.; Bednarkiewicz, A.; Samoć, M.; Wilk, K. A.

    2016-07-01

    An innovative approach for up-converting nanoparticles adaptation for bio-related and theranostic applications is presented. We have successfully encapsulated multiple, ~8 nm in size NaYF4 nanoparticles inside the polymeric nanocarriers with average size of ~150 nm. The initial coating of nanoparticles surfaces was preserved due to the hydrophobic environment inside the nanocapsules, and thus no single nanoparticle surface functionalization was necessary. The selection of biodegradable and sugar-based polyelectrolyte shells ensured biocompatibility of the nanostructures, while the choice of Tm3+ and Yb3+ NaYF4 nanoparticles co-doping allowed for near-infrared to near-infrared bioimaging of healthy and cancerous cell lines. The protective role of organic shell resulted in not only preserved high up-converted emission intensity and long luminescence lifetimes, without quenching from water environment, but also ensured low cytotoxicity and high cellular uptake of the engineered nanocapsules. The multifunctionality of the proposed nanocarriers is a consequence of both the organic exterior part that is accessible for conjugation with biologically important molecules, and the hydrophobic interior, which in future application may be used as a container for co-encapsulation of inorganic nanoparticles and anticancer drug cargo.

  12. Nanocapsules of therapeutic proteins with enhanced stability and long blood circulation for hyperuricemia management.

    PubMed

    Zhang, Xiaopei; Xu, Duo; Jin, Xin; Liu, Gan; Liang, Sheng; Wang, Hui; Chen, Wei; Zhu, Xinyuan; Lu, Yunfeng

    2017-06-10

    Among a broad spectrum of medical treatments, protein therapeutics holds tremendous opportunities for the treatment of metabolic disorders, cancer, autoimmune diseases and etc. Broad adaption of protein therapeutics, however, still remain challenging, not only because of poor protein stability, but they also experience fast clearance after administrated and elicit immune responses, resulting in undesirable biodistribution and short blood residence time. In this study, we demonstrate a novel protein delivery method via encapsulating therapeutic proteins within thin shells of poly(N-vinylpyrrolidone) (PVP), which leads to significantly improved protein stability, reduced macrophage uptake, prolonged circulation time and reduced immunogenicity. Exemplified with urate oxidase (UOx), the enzyme used for hyperuricemia treatment, as-formed UOx nanocapsules, n(UOx), exhibits enhanced stability, more significant therapeutic effects, and a more than 10-fold improvement in circulation time when compared with native UOx. This technology not only demonstrates the use of UOx nanocapsules for hyperuricemia management, but also provides a general approach for a broad spectrum of therapeutic proteins for in vivo applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Triple-Modal Imaging of Magnetically-Targeted Nanocapsules in Solid Tumours In Vivo

    PubMed Central

    Bai, Jie; Wang, Julie T.-W.; Rubio, Noelia; Protti, Andrea; Heidari, Hamed; Elgogary, Riham; Southern, Paul; Al-Jamal, Wafa' T.; Sosabowski, Jane; Shah, Ajay M.; Bals, Sara; Pankhurst, Quentin A.; Al-Jamal, Khuloud T.

    2016-01-01

    Triple-modal imaging magnetic nanocapsules, encapsulating hydrophobic superparamagnetic iron oxide nanoparticles, are formulated and used to magnetically target solid tumours after intravenous administration in tumour-bearing mice. The engineered magnetic polymeric nanocapsules m-NCs are ~200 nm in size with negative Zeta potential and shown to be spherical in shape. The loading efficiency of superparamagnetic iron oxide nanoparticles in the m-NC was ~100%. Up to ~3- and ~2.2-fold increase in tumour uptake at 1 and 24 h was achieved, when a static magnetic field was applied to the tumour for 1 hour. m-NCs, with multiple imaging probes (e.g. indocyanine green, superparamagnetic iron oxide nanoparticles and indium-111), were capable of triple-modal imaging (fluorescence/magnetic resonance/nuclear imaging) in vivo. Using triple-modal imaging is to overcome the intrinsic limitations of single modality imaging and provides complementary information on the spatial distribution of the nanocarrier within the tumour. The significant findings of this study could open up new research perspectives in using novel magnetically-responsive nanomaterials in magnetic-drug targeting combined with multi-modal imaging. PMID:26909110

  14. In vivo hair growth promotion effects of cosmetic preparations containing hinokitiol-loaded poly(epsilon-caprolacton) nanocapsules.

    PubMed

    Hwang, S L; Kim, J C

    2008-08-01

    Nanocapsules containing hinokitiol (HKL) were prepared by an emulsion-diffusion method. In an emulsification step in preparing nanocapsules, cetyltrimethylamonium chloride (CTAC) was employed as a cationic emulsifier, Poly(epsilon-caprolactone) (PCL) was use as a wall material and HKL dissolved in octylsalicylate (OS) was used as a core material. The submicron-sized nanoparticle was observed on a TEM. The size ranged 55-234 nm and the mean diameters were 223 nm, which were determined by a dynamic light scattering method. According to the results of pH-dependent microelectrophoresis, the absolute value of the surface potential of the nanocapsules was greater than 20 mV. The nanocapsules were colloidally stable over the pH range of 3-11. The nanocapsules were included in two kinds of preparations, namely shampoo and hair tonic, and the preparations were applied every day for 3 weeks on the clipped backs of 6 week-old mouse (C57BL/6) to investigate the hair growth-promoting effect. The degree of hair growth was evaluated by image-analysing the photographs of the backs and, in parallel, by the histological observation of the formation and the growth of hair or hair bulbs. The results were compared with those of commercially available Minoxidil solution (3%). Phosphate buffered saline was used as a control. The in vivo hair growth-promoting effects of the two preparations were comparable to those of Minoxidil solution. These results are in a good agreement with the histological and structural changes of follicles of the model animals, of which skins were treated with either the testing samples or the control in the same way the experiments of in vivo hair growth promotion were performed.

  15. In vitro cytotoxicity of Selol-loaded magnetic nanocapsules against neoplastic cell lines under AC magnetic field activation

    NASA Astrophysics Data System (ADS)

    Falqueiro, A. M.; Siqueira-Moura, M. P.; Jardim, D. R.; Primo, F. L.; Morais, P. C.; Mosiniewicz-Szablewska, E.; Suchocki, P.; Tedesco, A. C.

    2012-04-01

    The goals of this study are to evaluate invitro compatibility of magnetic nanomaterials and their therapeutic potential against cancer cells. Highly stable ionic magnetic fluid sample (maghemite, γ-Fe2O3) and Selol were incorporated into polymeric nanocapsules by nanoprecipitation method. The cytotoxic effect of Selol-loaded magnetic nanocapsules was assessed on murine melanoma (B16-F10) and oral squamous cell carcinoma (OSCC) cell lines following AC magnetic field application. The influence of different nanocapsules on cell viability was investigated by colorimetric MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. In the absence of AC magnetic field Selol-loaded magnetic nanocapsules, containing 100 µg/mL Selol plus 5 × 1012 particle/mL, showed antitumoral activity of about 50% on B16-F10 melanoma cells while OSCC carcinoma cells demonstrated drug resistance at all concentrations of Selol and magnetic fluid (range of 100-500 µg/mL Selol and 5 × 1012-2.5 × 1013 particle/mL). On the other hand, under AC applied fields (1 MHz and 40 Oe amplitude) B16-F10 cell viability was reduced down to 40.5% (±3.33) at the highest concentration of nanoencapsulated Selol. The major effect, however, was observed on OSCC cells since the cell viability drops down to about 33.3% (±0.38) under application of AC magnetic field. These findings clearly indicate that the Selol-loaded magnetic nanocapsules present different toxic effects on neoplastic cell lines. Further, the cytotoxic effect was maximized under AC magnetic field application on OSCC, which emphasizes the effectiveness of the magnetohyperthermia approach.

  16. Carbon-riveted Pt catalyst supported on nanocapsule MWCNTs-Al2O3 with ultrahigh stability for high-temperature proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Jiang, Zheng-Zhi; Wang, Zhen-Bo; Qu, Wei-Li; Rivera, Harry; Gu, Da-Ming; Yin, Ge-Ping

    2012-11-01

    Pt catalyst supported on nanocapsule MWCNTs-Al2O3 (multi-walled carbon nanotubes, MWCNTs) catalyst has been prepared by microwave-assisted polyol process (MAPP). The results of electrochemical measurements show that the nanocapsule Pt/MWCNTs-Al2O3 catalyst has higher activity due to more uniform dispersion and smaller size of Pt nanoparticles, and higher stability ascribed to the stronger metal-support interaction (SMSI) between Pt nanoparticles and nanocapsule support than in Pt/MWCNTs. Furthermore, the carbon-riveted nanocapsule Pt/MWCNTs-Al2O3 catalyst has been designed and synthesized on the basis of in situ carbonization of glucose. The physical characteristics such as X-ray diffraction (XRD), energy dispersive analysis of X-ray (EDAX), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) have indicated that α-Al2O3 indeed entered into the inside of the MWCNTs and formed a nanocapsule support of MWCNTs with α-Al2O3 as stuffing. The accelerated potential cycling tests (APCT) show that carbon-riveted nanocapsule Pt/MWCNTs-Al2O3 possesses 10 times the stability of Pt/C and has 4.5 times the life-span of carbon-riveted Pt/TiO2-C reported in our previous work. The significantly enhanced stability for carbon-riveted nanocapsule Pt/MWCNTs-Al2O3 catalyst is attributed to the reasons as follows: the inherently excellent mechanical resistance and stability of α-Al2O3 and MWCNTs in acidic and oxidative environments; SMSI between Pt nanoparticles and the nanocapsule support; the anchoring effect of the carbon layers formed during the carbon-riveting process (CRP); the increase of Pt(0) composition during CRP.

  17. Zeolitic imidazolate framework-8 (ZIF-8) as a sacrificial template: one-pot synthesis of hollow poly(dopamine) nanocapsules and yolk-structured poly(dopamine) nanocomposites

    NASA Astrophysics Data System (ADS)

    Ran, Jingyu; Xiao, Lihua; Wu, Weidang; Liu, Yike; Qiu, Wei; Wu, Jianming

    2017-02-01

    Hollow poly(dopamine) (PDA) nanocapsules and yolk-structured PDA nanocomposites were prepared by an aqueous one-pot synthesis method utilizing zeolitic imidazolate framework-8 (ZIF-8) nanocrystals as a sacrificial template without any special etchant. The resulting PDA nanocapsules show negligible cytotoxicity in HeLa cells after incubation for 48 h at various doses, which implies their potential as candidates for practical applications in drug transport and targeting.

  18. Zeolitic imidazolate framework-8 (ZIF-8) as a sacrificial template: one-pot synthesis of hollow poly(dopamine) nanocapsules and yolk-structured poly(dopamine) nanocomposites.

    PubMed

    Ran, Jingyu; Xiao, Lihua; Wu, Weidang; Liu, Yike; Qiu, Wei; Wu, Jianming

    2017-02-03

    Hollow poly(dopamine) (PDA) nanocapsules and yolk-structured PDA nanocomposites were prepared by an aqueous one-pot synthesis method utilizing zeolitic imidazolate framework-8 (ZIF-8) nanocrystals as a sacrificial template without any special etchant. The resulting PDA nanocapsules show negligible cytotoxicity in HeLa cells after incubation for 48 h at various doses, which implies their potential as candidates for practical applications in drug transport and targeting.

  19. Aqueous-core PEG-coated PLA nanocapsules for an efficient entrapment of water soluble anticancer drugs and a smart therapeutic response.

    PubMed

    Cosco, Donato; Paolino, Donatella; De Angelis, Francesco; Cilurzo, Felisa; Celia, Christian; Di Marzio, Luisa; Russo, Diego; Tsapis, Nicolas; Fattal, Elias; Fresta, Massimo

    2015-01-01

    Novel PEGylated PLA nanocapsules (PEG-AcPLA nanocapsules), loading high percentage of water soluble drugs have been formulated by using multiple emulsion technique without using conventional stabilizers. In particular, sodium deoxycholate hydrate has been used to obtain nanocapsules having a mean diameter of about 200 nm and a polydispersity index of ∼ 0.1. Gemcitabine hydrochloride (GEM) was used as a model of hydrophilic drug. GEM-loaded PEG-AcPLA nanocapsules demonstrated a high encapsulation efficacy and the drug-release followed a zero-order kinetic. MTT-assay evidenced an increased antitumor effect of GEM-loaded PEG-AcPLA nanocapsules compared to the free drug on different cancer cell lines and confocal laser scanning microscopy showed a significant improvement of cell interaction at 6h of incubation. In vivo anticancer activity of GEM-loaded PEG-AcPLA nanocapsules using two xenograft murine models of human solid tumors further supported the efficacy of this nano-drug, thus providing preliminary results about the potential clinical application of this innovative nanotherapeutic.

  20. Chemical Effects during Storage of Frozen Foods.

    ERIC Educational Resources Information Center

    Powrie, W. D.

    1984-01-01

    Discusses (1) characteristics, interrelationships, and distribution of food constituents (including water) in unfrozen food systems; (2) the freezing process; and (3) chemical changes in food during frozen storage. Protein alterations and lipid oxidation are emphasized. (JN)

  1. Defective Reduction in Frozen Pie Manufacturing Process

    NASA Astrophysics Data System (ADS)

    Nooted, Oranuch; Tangjitsitcharoen, Somkiat

    2017-06-01

    The frozen pie production has a lot of defects resulting in high production cost. Failure mode and effect analysis (FMEA) technique has been applied to improve the frozen pie process. Pareto chart is also used to determine the major defects of frozen pie. There are 3 main processes that cause the defects which are the 1st freezing to glazing process, the forming process, and the folding process. The Risk Priority Number (RPN) obtained from FMEA is analyzed to reduce the defects. If RPN of each cause exceeds 45, the process will be considered to be improved and selected for the corrective and preventive actions. The results showed that RPN values decreased after the correction. Therefore, the implementation of FMEA technique can help to improve the performance of frozen pie process and reduce the defects approximately 51.9%.

  2. Use of frozen section in genitourinary pathology.

    PubMed

    Shen, Steven S; Truong, Luan D; Ro, Jae Y; Ayala, Alberto G

    2012-08-01

    Frozen section diagnosis provides critical information for immediate surgical management decision making. Over the last several years, there have been some significant advances in treatment of genitourinary cancer, particularly with regard to surgical techniques. These changes in turn impact the type and frequency of intraoperative frozen section requests. In this review, we describe the main indications and diagnostic challenges of frozen section diagnosis during surgeries of each genitourinary organ system including prostate, kidney, bladder, testis, and penis. The pitfalls and approaches to different diagnostic situations are discussed. It is also stressed that pathologists must not only be familiar with the histological diagnosis, but also understand the limitations of frozen section diagnosis and communicate with urologists during the intraoperative treatment decision making process.

  3. Chemical Effects during Storage of Frozen Foods.

    ERIC Educational Resources Information Center

    Powrie, W. D.

    1984-01-01

    Discusses (1) characteristics, interrelationships, and distribution of food constituents (including water) in unfrozen food systems; (2) the freezing process; and (3) chemical changes in food during frozen storage. Protein alterations and lipid oxidation are emphasized. (JN)

  4. Artificial insemination of cranes with frozen semen

    USGS Publications Warehouse

    Gee, G.F.; Sexton, T.J.; Lewis, J.C.

    1979-01-01

    For the first time (1978) artificial insemination (AI) with frozen greater sandhill crane (Grus canadensis tabida) semen resulted in fertile eggs and chicks. During the 2 year (1977-78) study, 6 of 27 eggs produced were fertile. Three chicks hatched. Semen samples used for insemination were frozen and stored in liquid nitrogen for two months or less. Recent improvements in the laboratory indicated that a more effective sample can be prepared and greater fertility rates should be expected.

  5. Management of chickenpox with frozen mother's milk.

    PubMed

    Verd, Sergio; López, Esther

    2012-08-01

    If a mother has contracted chickenpox, the antibodies in her milk confer immunity against chickenpox to her breastfed babies. This passive immunization may avoid or spare the breastfed babies' symptoms of chickenpox. It is hypothesized that frozen breast milk may shorten chickenpox duration because specific antibodies against varicella zoster have been detected in human milk and they are resistant to digestion and are stable in frozen milk. The clinical outcomes of chickenpox in a 9-year-old boy and his father on frozen breast milk are reported. The study comprised a varicella-vaccine-refusing family attending a private office of pediatrics. The boy presented with a crusted varicella rash. The medical history revealed premature cessation of the typical varicella rash on day 3. It was coincidental with a supply of frozen human milk by his mother. Next, the father (41 years old) of this patient contracted chickenpox: he was on frozen breast milk from day 2, and no new pox emerged thereafter. The rash spread and numbered 50 to 150 lesions on day 2. Instead, the typical rash was expected to appear in three successive crops of lesions throughout the first week. The disease usually numbers approximately 250-500 lesions in unvaccinated healthy persons. Frozen breast milk may shorten chickenpox duration.

  6. [Scientific ethics and frozen embryos].

    PubMed

    Valenzuela, C Y

    2001-05-01

    Scientific Ethics is the theory and praxis of decisions. Philosophical Ethics is presented as the theory and praxis of the good. As the good differs among cultures, Philosophical Ethics is dependent on the endo-cultural good conception. The decision (included that one of adhesion or not to a world vision) depends on neuro-psychic specific factors: i) cognitive factors that include mostly the knowledge of the alternatives and their consequences and the ideological or religious conception of good in relation to the alternatives; ii) affective factors that make alternatives pleasant, unpleasant or neutral, attractive, repulsive or neutral; iii) emotional factors that associate to alternatives anger, peace or neutrality, sadness, happiness or neutrality; iv) value factors that assign importance, triviality or neutrality to alternatives, or assign them significance, irrelevancy or neutrality. There are unspecific factors such as the psychic energy, desire or others. Mixed factors such as attitude, motivation, intention and others. Scientific Ethics deals with the mind as a materio-energetic process which is different from the soul, eggs and embryos of any species are full individuals of that species, because, they have initiated a copy of their genome that specify, give autonomy and define them as individuals. For Scientific Ethics to leave frozen embryos like that for ever, to defrost and get rid of them or to use their cells for science are synonymous of killing them. To defrost them to use their cells as stem cells for somatic cell therapy or to implant them into uteri to continue their development is to maintain alive their cells, but only the implantation allows their maintenance as individuals, thus, being the only compatible with the Christian ethics. The compatibility of these alternatives with other ethics is discussed.

  7. 21 CFR 152.126 - Frozen cherry pie.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Frozen cherry pie. 152.126 Section 152.126 Food... HUMAN CONSUMPTION FRUIT PIES Requirements for Specific Standardized Fruit Pies § 152.126 Frozen cherry pie. (a) Identity. (1) Frozen cherry pie (excluding baked and then frozen) is the food prepared...

  8. 21 CFR 152.126 - Frozen cherry pie.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Frozen cherry pie. 152.126 Section 152.126 Food... HUMAN CONSUMPTION FRUIT PIES Requirements for Specific Standardized Fruit Pies § 152.126 Frozen cherry pie. (a) Identity. (1) Frozen cherry pie (excluding baked and then frozen) is the food prepared...

  9. 21 CFR 152.126 - Frozen cherry pie.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Frozen cherry pie. 152.126 Section 152.126 Food... HUMAN CONSUMPTION FRUIT PIES Requirements for Specific Standardized Fruit Pies § 152.126 Frozen cherry pie. (a) Identity. (1) Frozen cherry pie (excluding baked and then frozen) is the food prepared...

  10. 21 CFR 160.190 - Frozen egg yolks.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen egg yolks. 160.190 Section 160.190 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.190 Frozen egg yolks. (a) Frozen egg yolks, frozen yolks is the food prepared by freezing egg yolks...

  11. 21 CFR 160.190 - Frozen egg yolks.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Frozen egg yolks. 160.190 Section 160.190 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.190 Frozen egg yolks. (a) Frozen egg yolks, frozen yolks is the food prepared by freezing egg yolks...

  12. 21 CFR 160.150 - Frozen egg whites.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen egg whites. 160.150 Section 160.150 Food... HUMAN CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.150 Frozen egg whites. (a) Frozen egg whites, frozen egg albumen is the food prepared by...

  13. 21 CFR 160.150 - Frozen egg whites.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Frozen egg whites. 160.150 Section 160.150 Food... HUMAN CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.150 Frozen egg whites. (a) Frozen egg whites, frozen egg albumen is the food prepared by...

  14. 21 CFR 160.150 - Frozen egg whites.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Frozen egg whites. 160.150 Section 160.150 Food... HUMAN CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.150 Frozen egg whites. (a) Frozen egg whites, frozen egg albumen is the food prepared by...

  15. 21 CFR 160.190 - Frozen egg yolks.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Frozen egg yolks. 160.190 Section 160.190 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.190 Frozen egg yolks. (a) Frozen egg yolks, frozen yolks is the food prepared by freezing egg yolks...

  16. 21 CFR 160.190 - Frozen egg yolks.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Frozen egg yolks. 160.190 Section 160.190 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.190 Frozen egg yolks. (a) Frozen egg yolks, frozen yolks is the food prepared by freezing egg yolks...

  17. 21 CFR 160.150 - Frozen egg whites.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Frozen egg whites. 160.150 Section 160.150 Food... HUMAN CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.150 Frozen egg whites. (a) Frozen egg whites, frozen egg albumen is the food prepared by...

  18. 21 CFR 160.150 - Frozen egg whites.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Frozen egg whites. 160.150 Section 160.150 Food... HUMAN CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.150 Frozen egg whites. (a) Frozen egg whites, frozen egg albumen is the food prepared by...

  19. 21 CFR 160.190 - Frozen egg yolks.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Frozen egg yolks. 160.190 Section 160.190 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.190 Frozen egg yolks. (a) Frozen egg yolks, frozen yolks is the food prepared by freezing egg yolks...

  20. 21 CFR 152.126 - Frozen cherry pie.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen cherry pie. 152.126 Section 152.126 Food... HUMAN CONSUMPTION FRUIT PIES Requirements for Specific Standardized Fruit Pies § 152.126 Frozen cherry pie. (a) Identity. (1) Frozen cherry pie (excluding baked and then frozen) is the food prepared by...

  1. 21 CFR 152.126 - Frozen cherry pie.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Frozen cherry pie. 152.126 Section 152.126 Food... HUMAN CONSUMPTION FRUIT PIES Requirements for Specific Standardized Fruit Pies § 152.126 Frozen cherry pie. (a) Identity. (1) Frozen cherry pie (excluding baked and then frozen) is the food prepared by...

  2. Hollow graphitic nanocapsules as efficient electrode materials for sensitive hydrogen peroxide detection.

    PubMed

    Liu, Wei-Na; Ding, Ding; Song, Zhi-Ling; Bian, Xia; Nie, Xiang-Kun; Zhang, Xiao-Bing; Chen, Zhuo; Tan, Weihong

    2014-02-15

    Carbon nanomaterials are typically used in electrochemical biosensing applications for their unique properties. We report a hollow graphitic nanocapsule (HGN) utilized as an efficient electrode material for sensitive hydrogen peroxide detection. Methylene blue (MB) molecules could be efficiently adsorbed on the HGN surfaces, and this adsorption capability remained very stable under different pH regimes. HGNs were used as three-dimensional matrices for coimmobilization of MB electron mediators and horseradish peroxidase (HRP) to build an HGN-HRP-MB reagentless amperometric sensing platform to detect hydrogen peroxide. This simple HGN-HRP-MB complex demonstrated very sensitive and selective hydrogen peroxide detection capability, as well as high reproducibility and stability. The HGNs could also be utilized as matrices for immobilization of other enzymes, proteins or small molecules and for different biomedical applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. In situ targeted MRI detection of Helicobacter pylori with stable magnetic graphitic nanocapsules

    PubMed Central

    Li, Yunjie; Hu, Xiaoxiao; Ding, Ding; Zou, Yuxiu; Xu, Yiting; Wang, Xuewei; Zhang, Yin; Chen, Long; Chen, Zhuo; Tan, Weihong

    2017-01-01

    Helicobacter pylori infection is implicated in the aetiology of many diseases. Despite numerous studies, a painless, fast and direct method for the in situ detection of H. pylori remains a challenge, mainly due to the strong acidic/enzymatic environment of the gastric mucosa. Herein, we report the use of stable magnetic graphitic nanocapsules (MGNs), for in situ targeted magnetic resonance imaging (MRI) detection of H. pylori. Several layers of graphene as the shell effectively protect the magnetic core from corrosion while retaining the superior contrast effect for MRI in the gastric environment. Boronic-polyethylene glycol molecules were synthesized and modified on the MGN surface for targeted MRI detection. In a mouse model of H. pylori-induced infection, H. pylori was specifically detected through both T2-weighted MR imaging and Raman gastric mucosa imaging using functionalized MGNs. These results indicated that enhancement of MRI using MGNs may be a promising diagnostic and bioimaging platform for very harsh conditions. PMID:28643777

  4. Controlled formation of polymer nanocapsules with high diffusion-barrier properties and prediction of encapsulation efficiency.

    PubMed

    Hofmeister, Ines; Landfester, Katharina; Taden, Andreas

    2015-01-02

    Polymer nanocapsules with high diffusion-barrier performance were designed following simple thermodynamic considerations. Hindered diffusion of the enclosed material leads to high encapsulation efficiencies (EEs), which was demonstrated based on the encapsulation of highly volatile compounds of different chemical natures. Low interactions between core and shell materials are key factors to achieve phase separation and a high diffusion barrier of the resulting polymeric shell. These interactions can be characterized and quantified using the Hansen solubility parameters. A systematic study of our copolymer system revealed a linear relationship between the Hansen parameter for hydrogen bonding (δh ) and encapsulation efficiencies which enables the prediction of encapsulated amounts for any material. Furthermore EEs of poorly encapsulated materials can be increased by mixing them with a mediator compound to give lower overall δh values.

  5. Bioreducible nanocapsules prepared from the self-assembly of branched polymer in nanodroplet.

    PubMed

    Wang, Long-Hai; Ding, Sheng-Gang; Yan, Jun-Jie; You, Ye-Zi

    2014-02-01

    Though great attention has been paid in constructing well-defined nano-structures via the self-assembly of amphiphilic macromolecules, the self-assembly of non-amphiphilic macromolecules in nanodroplet has drawn less attention up to now. Recently, we prepared a temperature-responsive PEG-based branched polymer with disulfide bonds in its backbone via reversible addition-fragmentation chain transfer (RAFT) polymerization of 2-(2-methoxyethoxy) ethyl methacrylate, oligo(ethylene glycol) methacrylate, and N,N'-cystamine bisacrylamide. Subsequently, we loaded the branched polymer into nanodroplets, and have found that the self-assembly behaviors of this branched poly-mer in the nanodroplet are different from those in common solution. Bioreducible nanocapsules with tunable size can easily formed in nanodroplet even at high concentration.

  6. Nanostructured chitosan-surfactant matrices as polyphenols nanocapsules template with zero order release kinetics.

    PubMed

    Gârlea, Ana; Melnig, V; Popa, M I

    2010-04-01

    Nanostructured membranes and films of cationic surfactant-chitosan with tannic acid as polyphenol model were obtained by phase inversion method. The membranes were investigated by Attenuated Total Reflectance Fourier Transform InfraRred, X-Ray Diffraction, Scanning Electron Microscopy and Thermogravimetry, and the films topography was analysed by Atomic Force Microscopy. The analysis reveals that the interactions at the molecular level between cationic CTAB surfactant and cationic chitosan polymer strive to weaken membrane stability, whereas, the tannic acid is favoured to cluster with CTAB and diminish the membrane thermodynamic instability. The nanocapsules formed, with dimensions in the range of 16.35-27.68 nm, are congregating in clusters having dimensions in the domain of 50-300 nm. The layers resulted from these nanostructures arrangement constitute a surfactant-chitosan matrix with tannic acid suitable for drug controlled release with zero order kinetics.

  7. Understanding the self-assembly process and behavior of metal-seamed pyrogallol[4]arene nanocapsules

    NASA Astrophysics Data System (ADS)

    Mossine, Andrew V.

    C-alkylpyrogallol[4]arenes (PgCs) are bowl-shaped compounds that are commonly used as supramolecular building blocks in the construction of larger entities such as capsules, nanotubes, and layered networks. Many of these assemblies are constructed using non-covalent means and, as such, are inherently unstable in polar media. Although metal coordination with the hydroxyl-rich PgC upper rim can be exploited to synthesize assemblies with enhanced stability, few reports of this can be found in the literature. Thus, a thorough investigation of these metal-seamed assemblies and their manipulation is of importance. Prior work in the Atwood lab has produced three examples of metal-organic nanocapsules (MONCs) based on PgCs. These include two hexameric MONCs (based on Cu2+ and Ga3+) as well as a single example of a dimeric MONC (based on Zn2+). As it was unknown whether other metal cations could lead to the formation of similar entities, PgC complexation experiments were conducted with other first series transition metal cations, notably Ni2+, Co2+ and Mn2+. All of these led to nanocapsular materials, which were identified and studied using single crystal X-ray diffraction (scXRD). Once the foundational studies were complete, syntheses were also performed under varied conditions, specifically with Ni2+ and Cu2+. This led to the characterization of both dimeric and hexameric MONCs with these two metals, as well as the characterization of many other capsular materials. The information collected from these experiments also led to an intriguing question: which specific conditions lead to the formation of dimeric vs. hexameric MONCs? To answer this question, solid-state analysis using scXRD was coupled to in situ analysis utilizing small angle neutron scattering (SANS). This work showed that the formation of the dimer is typically favored at higher temperatures while the formation of the hexamer is favored at lower temperatures for both of the metals tested. Studies that varied

  8. Pyrimethamine-loaded lipid-core nanocapsules to improve drug efficacy for the treatment of toxoplasmosis.

    PubMed

    Pissinate, Kenia; dos Santos Martins-Duarte, Érica; Schaffazick, Scheila Rezende; de Oliveira, Catiúscia Padilha; Vommaro, Rossiane Cláudia; Guterres, Sílvia Stanisçuaski; Pohlmann, Adriana Raffin; de Souza, Wanderley

    2014-02-01

    We propose an innovative product based on the nanoencapsulation of pyrimethamine (PYR), aiming an improvement of drug efficacy for the treatment of toxoplasmosis. The in vitro cytotoxicity effect of encapsulated PYR and PYR-colloidal suspension was concomitantly evaluated against LLC-MK2 lineage and mouse peritoneal macrophage showing that the cells had similar tolerance for both PYR encapsulated or in the aqueous suspension. CF1 mice acutely infected with tachyzoites of Toxoplasma gondii RH strain treated with different doses (5.0-10 mg/kg/day) of PYR-nanocapsules had survival rate higher than the animals treated with the same doses of non-encapsulated PYR. Thus, encapsulation of PYR improved the efficacy of this drug against an acute model of toxoplasmosis in mice and can be considered an alternative for reducing the dose of PYR, which, in turn, could also reduce the side effects associated to the treatment.

  9. Applications of nanosystems to anticancer drug therapy (Part I. Nanogels, nanospheres, nanocapsules).

    PubMed

    Talevi, Alan; Gantner, Melisa E; Ruiz, María E

    2014-01-01

    One of the greatest challenges in cancer drug therapy is to maximize the effectiveness of the active agent while reducing its systemic adverse effects. To add more, many widely-used chemoterapeutic agents present unfavorable physicochemical properties (e.g. low solubility, lack of chemical or biological stability) that hamper or limit their therapeutic applications. All these issues may be overcome by designing adequate drug delivery systems; nanocarriers are particularly suitable for this purpose. Nanosystems can be used for targeted-drug release, treatment, diagnostic imaging and therapy monitoring. They allow the formulation of drug delivery systems with user-defined characteristics regarding solubility, biodegradability, particle size, release kinetics and active targeting, among others. This review (Part I) focuses on recent patents published between 2008 and the present day, related to nanospheres, nanocapsules and nanogels applied to anticancer drug therapy. Other nanosystems is covered in a second article (Part II).

  10. Ultralight Fe@C Nanocapsules/Sponge Composite with Reversibly Tunable Microwave Absorption Performances.

    PubMed

    Li, Yixing; Mao, Zhe; Liu, Rongge; Zhao, Xiaoning; Zhang, Yanhui; Qin, Gaowu; Zhang, Xuefeng

    2017-08-11

    Microwave absorbers are usually designed to solve electromagnetic interferences at a specific frequency, while the requirements may be dynamic during service life. Therefore, a recoverable tuning for microwave absorption properties in response to an external stimulus would be highly desirable. We herein present a micro/nano-scale hybrid absorber, in which high-performance Fe@C nanocapsule absorbents are integrated with a porous melamine sponge skeleton, exhibiting multiple merits of light weight, strong absorption and high elasticity. By mechanically compressing and decompressing the absorber, microwave absorption performances can be effectively shifted between 18 GHz and 26.5 GHz. The present study thus provides a new strategy for the design of a 'dynamic' microwave absorber.

  11. Lipid Nanocapsule-Based Gels for Enhancement of Transdermal Delivery of Ketorolac Tromethamine

    PubMed Central

    Varshosaz, Jaleh; Hajhashemi, Valiollah; Soltanzadeh, Sindokht

    2011-01-01

    Previous reports show ineffective transdermal delivery of ketorolac by nanostructured lipid carriers (NLCs). The aim of the present work was enhancement of transdermal delivery of ketorolac by another colloidal carriers, lipid nanocapsules (LNCs). LNCs were prepared by emulsification with phase transition method and mixed in a Carbomer 934P gel base with oleic acid or propylene glycol as penetration enhancers. Permeation studies were performed by Franz diffusion cell using excised rat abdominal skin. Aerosil-induced rat paw edema model was used to investigate the in vivo performance. LNCs containing polyethylene glycol hydroxyl stearate, lecithin in Labrafac as the oily phase, and dilution of the primary emulsion with 3.5-fold volume of cold water produced the optimized nanoparticles. The 1% Carbomer gel base containing 10% oleic acid loaded with nanoparticles enhanced and prolonged the anti-inflammatory effects of this drug to more than 12 h in Aerosil-induced rat paw edema model. PMID:22175029

  12. In situ targeted MRI detection of Helicobacter pylori with stable magnetic graphitic nanocapsules

    NASA Astrophysics Data System (ADS)

    Li, Yunjie; Hu, Xiaoxiao; Ding, Ding; Zou, Yuxiu; Xu, Yiting; Wang, Xuewei; Zhang, Yin; Chen, Long; Chen, Zhuo; Tan, Weihong

    2017-06-01

    Helicobacter pylori infection is implicated in the aetiology of many diseases. Despite numerous studies, a painless, fast and direct method for the in situ detection of H. pylori remains a challenge, mainly due to the strong acidic/enzymatic environment of the gastric mucosa. Herein, we report the use of stable magnetic graphitic nanocapsules (MGNs), for in situ targeted magnetic resonance imaging (MRI) detection of H. pylori. Several layers of graphene as the shell effectively protect the magnetic core from corrosion while retaining the superior contrast effect for MRI in the gastric environment. Boronic-polyethylene glycol molecules were synthesized and modified on the MGN surface for targeted MRI detection. In a mouse model of H. pylori-induced infection, H. pylori was specifically detected through both T2-weighted MR imaging and Raman gastric mucosa imaging using functionalized MGNs. These results indicated that enhancement of MRI using MGNs may be a promising diagnostic and bioimaging platform for very harsh conditions.

  13. Ultralight Fe@C Nanocapsules/Sponge Composite with Reversibly Tunable Microwave Absorption Performances

    NASA Astrophysics Data System (ADS)

    Li, Yixing; Mao, Zhe; Liu, Rongge; Zhao, Xiaoning; Zhang, Yanhui; Qin, Gaowu; Zhang, Xuefeng

    2017-08-01

    Microwave absorbers are usually designed to solve electromagnetic interferences at a specific frequency, while the requirements may be dynamic during service life. Therefore, a recoverable tuning for microwave absorption properties in response to an external stimulus would be highly desirable. We herein present a micro/nano-scale hybrid absorber, in which high-performance Fe@C nanocapsule absorbents are integrated with a porous melamine sponge skeleton, exhibiting multiple merits of light weight, strong absorption and high elasticity. By mechanically compressing and decompressing the absorber, microwave absorption performances can be effectively shifted between 18 GHz and 26.5 GHz. The present study thus provides a new strategy for the design of a ‘dynamic’ microwave absorber.

  14. 21 CFR 146.137 - Frozen orange juice.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Frozen orange juice. 146.137 Section 146.137 Food... Beverages § 146.137 Frozen orange juice. (a) Frozen orange juice is orange juice as defined in § 146.135, except that it is frozen. (b) The name of the food is “Frozen orange juice”. Such name may be preceded...

  15. 21 CFR 146.137 - Frozen orange juice.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen orange juice. 146.137 Section 146.137 Food... Beverages § 146.137 Frozen orange juice. (a) Frozen orange juice is orange juice as defined in § 146.135, except that it is frozen. (b) The name of the food is “Frozen orange juice”. Such name may be preceded...

  16. 21 CFR 146.137 - Frozen orange juice.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Frozen orange juice. 146.137 Section 146.137 Food... Beverages § 146.137 Frozen orange juice. (a) Frozen orange juice is orange juice as defined in § 146.135, except that it is frozen. (b) The name of the food is “Frozen orange juice”. Such name may be preceded on...

  17. 21 CFR 146.137 - Frozen orange juice.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Frozen orange juice. 146.137 Section 146.137 Food... Beverages § 146.137 Frozen orange juice. (a) Frozen orange juice is orange juice as defined in § 146.135, except that it is frozen. (b) The name of the food is “Frozen orange juice”. Such name may be preceded on...

  18. 21 CFR 146.137 - Frozen orange juice.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Frozen orange juice. 146.137 Section 146.137 Food... Beverages § 146.137 Frozen orange juice. (a) Frozen orange juice is orange juice as defined in § 146.135, except that it is frozen. (b) The name of the food is “Frozen orange juice”. Such name may be preceded on...

  19. Evaluation of tea tree oil for controlling Rhipicephalus microplus in dairy cows.

    PubMed

    Pazinatto Boito, Jhonatan; Santos, Roberto C; Vaucher, Rodrigo A; Raffin, Renata; Machado, Gustavo; Tonin, Alexandre A; Da Silva, Aleksandro S

    2016-07-30

    Our research aimed to test the effects of Melaleuca alternifolia oil (pure and in nanocapsules) in the control of Rhipicephalus microplus in dairy cattle. For this purpose, the in vivo studies used 15 cows distributed in three different groups with the same number of animals. Five cows remained untreated (Group A), representing the control group; other five cows were sprayed with TTO (at 5%) in its pure form (Group B); and five cows were sprayed with nanocapsules of TTO (at 0.75%) (Group C). On days 1 and 4 post-treatments (PT), all cows had their ticks counted. On day 1 PT, two ticks from each cow were collected to evaluate the effect of the treatment on ticḱs reproduction (in vitro assays). The pure form of TTO caused a significant reduction (P<0.05) in the number of ticks from the Group B compared to the Group A on day 4 PT. However, there was no significant difference in the number of ticks on cows from Groups A and C after treatment (P>0.05). Treatment with TTO in nanocapsules (Group C) interfered with R. microplus reproduction, leading to lower oviposition by female ticks and hatchability (34.5% of efficacy). On the other hand, TTO oil (Group B) did not interfere on ticḱs reproduction, i.e. showed higher hatchability than the control group. Therefore, it is possible to conclude that pure TTO has an acaricidal effect in dairy cows, in addition to an effect on ticḱs reproduction when used its nanocapsulated form. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. 1H NMR Self-Diffusion in Polymer-Surfactant Nanocapsules and Cryogels with Enzyme.

    PubMed

    Shapiro; Pykhteeva; Levashov

    1998-10-01

    The multicomponent self-diffusion in nanocapsules and cryogel biocatalytic systems containing alpha-chymotrypsin has been studied with the NMR-PGSE method at various temperatures and compared with the diffusion of such systems without enzyme. Unilamellar vesicles have been formed in water after "coating" with Brij-97 of the poly-(N,N-diallyl-N,N-didodecyl ammonium bromide), poly-DDAB, nanocapsules. The latter have been obtained by UV-irradiation of reversed hydrated micelles from DDAB in cyclohexane. Cryogels were made from poly(vinyl alcohol), PVA, aqueous solutions by a freezing-thawing cyclic process. Both compartmented systems were used as vehicles of the enzyme entrapped in inner aqueous cavities. The activation energies of self-diffusion for both these systems have been calculated. These data contain information concerning morphology and molecular packing. Encapsulation of alpha-chymotrypsin in the poly-DDAB/Brij-97 vesicles and the PVA cryogel lowers the Ds values for all molecules and shifts the cloud point toward the lower temperature. On the contrary, the syneresis point for the PVA cryogel is shifted for 8 degrees toward the higher temperature by the entrapment of the enzyme. Besides, entrapment of alpha-chymotrypsin in the cryogel promotes the increase of the Ea values for the PVA chain on 1.5 kJ/mol below the syneresis point. Such a difference indicates the influence of the H-bond system of PVA hydroxyl groups and water molecules on the interference of the protein globule. Entrapment of alpha-chymotrypsin leads to consolidation of this H-bond system. Copyright 1998 Academic Press.

  1. Mineralization of cellulose in frozen boreal soils

    NASA Astrophysics Data System (ADS)

    Oquist, Mats G.; Segura, Javier; Sparrman, Tobias; Nilsson, Mats; Schleucher, Jurgen

    2015-04-01

    Soils of high-latitude ecosystems store a large fraction of the global soil carbon. In boreal forests, the microbial mineralization of soil organic matter (SOM) during winter can affect the ecosystems net carbon balance. Recent research has shown that microorganisms in the organic surface layer of boreal forest soil can mineralize and grow on simple, soluble monomeric substrates under frozen conditions. However, any substantial impacts of microbial activity in frozen soils on long-term soil carbon balances ultimately depends on whether soil microorganisms can utilize and grow the more complex, polymeric constituents of SOM. In order to evaluate the potential for soil microorganisms to metabolize carbon polymers at low temperatures, we incubated boreal forest soil samples amended with [13C]-cellulose and studied the microbial catabolic and anabolic utilization of the substrate under frozen and unfrozen conditions (-4 and +4°C). Freezing of the soil markedly reduced microbial utilization of the cellulose. The [13C]-CO2 production rate in the samples at +4°C were 0.52 mg CO2 SOM -1 day-1 while rates in the frozen samples (-4°C) were 0.01 mg CO2 SOM -1 day-1. However, newly synthetized [13C]-enriched cell membrane lipids, PLFAs, were detected in soil samples incubated both above and below freezing, confirming that cellulose can sustain also anabolic activity of the microbial populations under frozen conditions. The reduced metabolic rates induced by freezing indicate constraints on exoenzymatic activity, as well as substrate diffusion rates that we can attribute to reduced liquid water content of the frozen soil. We conclude that the microbial population in boreal forest soil has the capacity to metabolize, and grow, on polymeric substrates at temperatures below zero, which involves maintaining exoenzymatic activity in frozen soils. This capacity manifests the importance of SOM mineralization during the winter season and its importance for the net carbon balance of

  2. Effect of coating material on uptake of indocyanine green-loaded nanocapsules by HeLa cervical cancer cells

    NASA Astrophysics Data System (ADS)

    Jung, Bongsu; Lomeli, Eulieses; Anvari, Bahman

    2010-02-01

    Fluorescent molecular probes offer a potential for early cancer detection. Indocyanine green (ICG) is an FDAapproved near-infrared (NIR) fluorescent dye used in ophthalmic angiography and assessment of cardiac and hepatic functions. However, clinical applications of ICG remain very limited due to its rapid clearance from vascular circulation, unstable optical properties, non-specific interactions with plasma proteins, and inability for localized targeting. To overcome these limitations, we have encapsulated ICG within nanoconstructs composed of poly(allylamine) hydrochloride and disodium hydrogen phosphate salt. To understand the effects of coating materials on the cellular uptake of the nanocapsules, we have measured the uptake of ICG-loaded nanocapsules (ICG-NCs) with various coating materials by HeLa cancerous cervical epithelial cells in-vitro. Results of this study provide important information for the choice of appropriate coating materials that will result in maximal uptake of ICG-NCs in optical and phototherapy of cancerous tissue.

  3. Development and validation of a fast RP-HPLC method for the determination of clobetasol propionate in topical nanocapsule suspensions.

    PubMed

    Fontana, M C; Bastos, M O; Beck, R C R

    2010-09-01

    A simple and rapid high-performance liquid chromatographic method is validated for the determination of clobetasol propionate in topical nanocapsule suspensions. The method is carried out on an RP-18 column with a mobile phase composed of methanol-water (80:20 v/v) and UV detection at 241 nm. The method validation yields good results with respect to linearity, specificity, precision, accuracy, and robustness. The calibration curve in the range of 5.0-40.0 microg/mL shows a correlation coefficient of 0.9999. Precision (intra-day and inter-day) is demonstrated by a relative standard deviation lower than 1.5%. Accuracy is assessed by the recovery test of clobetasol propionate from sample matrixes (98.33 +/- 0.88%). In conclusion, the method is suitable to be applied to assay clobetasol propionate in topical formulations of polymeric nanocapsules, avoiding the use of a buffer solution in the mobile phase.

  4. Gold nanoshelled liquid perfluorocarbon magnetic nanocapsules: a nanotheranostic platform for bimodal ultrasound/magnetic resonance imaging guided photothermal tumor ablation.

    PubMed

    Ke, Hengte; Wang, Jinrui; Tong, Sheng; Jin, Yushen; Wang, Shumin; Qu, Enze; Bao, Gang; Dai, Zhifei

    2013-01-01

    Imaging guided ablation therapy has been applied in both biomedical research and clinical trials and turned out to be one of the most promising approaches for cancer treatment. Herein, the multifunctional nanocapsules were fabricated through loading perfluorooctylbromide (PFOB) and superparamagnetic iron oxide nanoparticles (SPIOs) into poly(lactic acid) (PLA) nanocapsules (NCs), followed by the formation of PEGylated gold nanoshell on the surface. The resulting multi-component NCs were proved to be able to act as nanotheranostic agent to achieve successful bimodal ultrasound (US)/magnetic resonance imaging (MRI) guided photothermal ablation in human tumor xenograft models non-invasively. Such a single theranostic agent with the combination of real-time US and high-resolution MR imaging would be of great value to offer more comprehensive diagnostic information and dynamics of disease progression for the accurate location of therapeutic focusing spot in the targeted tumor tissue, showing great potential as an effective nanoplatform for contrast imaging guided photothermal therapy.

  5. Releasable Layer-by-Layer Assembly of Stabilized Lipid Nanocapsules on Microneedles for Enhanced Transcutaneous Vaccine Delivery

    PubMed Central

    DeMuth, Peter C.; Moon, James J.; Suh, Heikyung; Hammond, Paula T.; Irvine, Darrell J.

    2012-01-01

    Here we introduce a new approach for transcutaneous drug delivery, using microneedles coated with stabilized lipid nanocapsules for delivery of a model vaccine formulation. Poly(lactide-co-glycolide) (PLGA) microneedle arrays were coated with multilayer films via layer-by-layer (LbL) assembly of a biodegradable cationic poly(β-amino ester) (PBAE) and negatively-charged interbilayer-crosslinked multilamellar lipid vesicles (ICMVs). To test the potential of these nanocapsule-coated microneedles for vaccine delivery, we loaded ICMVs with a protein antigen and the molecular adjuvant monophosphoryl lipid A (MPLA). Following application of microneedle arrays to the skin of mice for 5 minutes, (PBAE/ICMV) films were rapidly transferred from microneedle surfaces into the cutaneous tissue, and remained in the skin following removal of the microneedle arrays. Multilayer films implanted in the skin dispersed ICMV cargos in the treated tissue over the course of 24 hours in vivo, allowing for uptake of the lipid nanocapsules by antigen presenting cells (APCs) in the local tissue and triggering their activation in situ. Microneedle-mediated transcutaneous vaccination with ICMV-carrying multilayers promoted robust antigen-specific humoral immune responses with a balanced generation of multiple IgG isotypes, whereas bolus delivery of soluble or vesicle-loaded antigen via intradermal injection or transcutaneous vaccination with microneedles encapsulating soluble protein elicited weak, IgG1-biased humoral immune responses. These results highlight the potential of lipid nanocapsules delivered by microneedles as a promising platform for non-invasive vaccine delivery applications. PMID:22920601

  6. Biosafety of Non-Surface Modified Carbon Nanocapsules as a Potential Alternative to Carbon Nanotubes for Drug Delivery Purposes

    PubMed Central

    Tang, Alan C. L.; Hwang, Gan-Lin; Chang, Min-Yao; Tang, Zack C. W.; Tsai, Meng-Da; Luo, Chwan-Yao; Hoffman, Allan S.; Hsieh, Patrick C. H.

    2012-01-01

    Background Carbon nanotubes (CNTs) have found wide success in circuitry, photovoltaics, and other applications. In contrast, several hurdles exist in using CNTs towards applications in drug delivery. Raw, non-modified CNTs are widely known for their toxicity. As such, many have attempted to reduce CNT toxicity for intravenous drug delivery purposes by post-process surface modification. Alternatively, a novel sphere-like carbon nanocapsule (CNC) developed by the arc-discharge method holds similar electric and thermal conductivities, as well as high strength. This study investigated the systemic toxicity and biocompatibility of different non-surface modified carbon nanomaterials in mice, including multi-walled carbon nanotubes (MWCNTs), single-walled carbon nanotubes (SWCNTs), carbon nanocapsules (CNCs), and C60 fullerene (C60). The retention of the nanomaterials and systemic effects after intravenous injections were studied. Methodology and Principal Findings MWCNTs, SWCNTs, CNCs, and C60 were injected intravenously into FVB mice and then sacrificed for tissue section examination. Inflammatory cytokine levels were evaluated with ELISA. Mice receiving injection of MWCNTs or SWCNTs at 50 µg/g b.w. died while C60 injected group survived at a 50% rate. Surprisingly, mortality rate of mice injected with CNCs was only at 10%. Tissue sections revealed that most carbon nanomaterials retained in the lung. Furthermore, serum and lung-tissue cytokine levels did not reveal any inflammatory response compared to those in mice receiving normal saline injection. Conclusion Carbon nanocapsules are more biocompatible than other carbon nanomaterials and are more suitable for intravenous drug delivery. These results indicate potential biomedical use of non-surface modified carbon allotrope. Additionally, functionalization of the carbon nanocapsules could further enhance dispersion and biocompatibility for intravenous injection. PMID:22457723

  7. Synthesis of multi-functional nanocapsules via interfacial AGET ATRP in miniemulsion for tumor micro-environment responsive drug delivery.

    PubMed

    Tian, Kun; Zeng, Jin; Zhao, Xubo; Liu, Lei; Jia, Xu; Liu, Peng

    2015-10-01

    Novel multi-functional polymeric hollow nanocapsules (PHN) based on the crosslinked poly(tert-butyl acrylate) (PtBA) shells were synthesized in a miniemulsion interfacial polymerization via activator generated electron transfer atom transfer radical polymerization (AGET ATRP) technique with N,N'-bis(acryloyl) cystamine (BACy) as cross-linking agent, CuBr₂ as catalyst, ascorbic acid (VC) as reducing agent and hexadecane as inert solvent. In the AGET ATRP, a folate-conjugated block copolymer, folate-poly(ethylene glycol)-b-poly(tert-butyl acrylate) (FA-PEG-tBA-Br), was used as macroinitiator/stabilizer, and the specific amphiphilic nature of the copolymer led the extending inward of polymer chains. The DLS analysis directly showed the PHN with an average diameter of 150 nm was obtained. After the PtBA shells were transformed into poly(acrylic acid) (PAA) by hydrolysis, doxorubicin (DOX), as a model drug, was loaded efficiently into the hydrolyzed polymeric hollow nanocapsules (HPHN), then the in vitro release of drug was carried out in phosphate buffer solution (PBS, pH 7.4 or 5.0, with or without DTT or GSH of different concentrations). It showed that the existence of folate group significantly improved pH stimuli-responsive and DOX-loading capacity of the polymeric nanocapsules. An acidic pH (5.0) and presence of GSH would accelerate the DOX release behavior. Thus, these multi-functional polymeric nanocapsules have excellent available properties in the field of targeted and controlled drug delivery for cancer therapy. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Fall Speeds of Freezing and Frozen Raindrops

    NASA Astrophysics Data System (ADS)

    Flynn, A. M.; Rahman, K. M.; Testik, F. Y.

    2016-12-01

    In this study, we investigated the fall speeds of freezing and frozen raindrops through field observations. While there have been many studies on the fall speed of warm raindrops (i.e. raindrops that are in liquid state during fall and after impact on a surface), yielding a number of parameterizations to predict the terminal fall speed of warm raindrops, such studies are limited for freezing and frozen raindrops. Moreover, the parameterizations developed for predicting the terminal fall speeds of warm raindrops are not applicable to freezing and frozen raindrops. The information on freezing and frozen raindrop fall speeds has important meteorological applications: for example, identification of precipitation type and radar retrieval of precipitation rates during such events. In this study, field data was collected using a new instrument called the High-speed Optical Disdrometer (HOD) that we recently developed. This data provided valuable insights into fall speeds of freezing and frozen raindrops, which will be discussed in our presentation. This material is based upon work supported by the National Science Foundation under Grants No. AGS-1144846 and AGS-1612681.

  9. 3D printed tablets loaded with polymeric nanocapsules: An innovative approach to produce customized drug delivery systems.

    PubMed

    Beck, R C R; Chaves, P S; Goyanes, A; Vukosavljevic, B; Buanz, A; Windbergs, M; Basit, A W; Gaisford, S

    2017-08-07

    The generation of multi-functional drug delivery systems, namely solid dosage forms loaded with nano-sized carriers, remains little explored and is still a challenge for formulators. For the first time, the coupling of two important technologies, 3D printing and nanotechnology, to produce innovative solid dosage forms containing drug-loaded nanocapsules was evaluated here. Drug delivery devices were prepared by fused deposition modelling (FDM) from poly(ε-caprolactone) (PCL) and Eudragit(®) RL100 (ERL) filaments with or without a channelling agent (mannitol). They were soaked in deflazacort-loaded nanocapsules (particle size: 138nm) to produce 3D printed tablets (printlets) loaded with them, as observed by SEM. Drug loading was improved by the presence of the channelling agent and a linear correlation was obtained between the soaking time and the drug loading (r(2)=0.9739). Moreover, drug release profiles were dependent on the polymeric material of tablets and the presence of the channelling agent. In particular, tablets prepared with a partially hollow core (50% infill) had a higher drug loading (0.27% w/w) and faster drug release rate. This study represents an original approach to convert nanocapsules suspensions into solid dosage forms as well as an efficient 3D printing method to produce novel drug delivery systems, as personalised nanomedicines. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Pharmacokinetics on a microscale: visualizing Cy5-labeled oligonucleotide release from poly(n-butylcyanoacrylate) nanocapsules in cells

    PubMed Central

    Tomcin, Stephanie; Baier, Grit; Landfester, Katharina; Mailänder, Volker

    2014-01-01

    For successful design of a nanoparticulate drug delivery system, the fate of the carrier and cargo need to be followed. In this work, we fluorescently labeled poly(n-butylcyanoacrylate) (PBCA) nanocapsules as a shell and separately an oligonucleotide (20 mer) as a payload. The nanocapsules were formed by interfacial anionic polymerization on aqueous droplets generated by an inverse miniemulsion process. After uptake, the PBCA capsules were shown to be round-shaped, endosomal structures and the payload was successfully released. Cy5-labeled oligonucleotides accumulated at the mitochondrial membrane due to a combination of the high mitochondrial membrane potential and the specific molecular structure of Cy5. The specificity of this accumulation at the mitochondria was shown as the uncoupler dinitrophenol rapidly diminished the accumulation of the Cy5-labeled oligonucleotide. Importantly, a fluorescence resonance energy transfer investigation showed that the dye-labeled cargo (Cy3/Cy5-labeled oligonucleotides) reached its target site without degradation during escape from an endosomal compartment to the cytoplasm. The time course of accumulation of fluorescent signals at the mitochondria was determined by evaluating the colocalization of Cy5-labeled oligonucleotides and mitochondrial markers for up to 48 hours. As oligonucleotides are an ideal model system for small interfering RNA PBCA nanocapsules demonstrate to be a versatile delivery platform for small interfering RNA to treat a variety of diseases. PMID:25473285

  11. Characterization of rheology and release profiles of olanzapine-loaded lipid-core nanocapsules in thermosensitive hydrogel.

    PubMed

    Dimer, F A; Pohlmann, A R; Guterres, S S

    2013-12-01

    In this study we developed a new drug delivery system for olanzanpine comprised of drug-loaded lipid-core nanocapsules incorporated in a thermosensitive hydrogel, intended to sustain the drug release. Firstly, olanzapine, a hydrophobic drug, was loaded in poly(epsilon-caprolactone) lipid core nanocapsules prepared by interfacial deposition of preformed polymer. The effects of the presence of ethanol and the amounts of sorbitan monostearate and medium-chain triglycerides on the particle size, zeta potential, polydispersity index, presence of microparticles and encapsulation efficiency were investigated using a 2(3) factorial design. The optimized nanocapsules were incorporated into a hydrophilic polymer (Poloxamer 407) dispersion in order to obtain a thermosensitive gel. The formulation containing 0.077 g of sorbitan monostearate, 0.22 ml of medium-chain triglycerides, 3 ml of ethanol and 18% of the thermosensitive polymer was selected according to the physicochemical properties. The rheology and release profiles of the mixed hydrophobic and hydrophilic delivery system were successfully characterized and revealed its great potential for the administration of hydrophobic drugs such as olanzapine with sustained in situ drug release.

  12. Evaluation of antimicrobial activity of glycerol monolaurate nanocapsules against American foulbrood disease agent and toxicity on bees.

    PubMed

    Lopes, Leonardo Q S; Santos, Cayane G; de Almeida Vaucher, Rodrigo; Gende, Liesel; Raffin, Renata P; Santos, Roberto C V

    2016-08-01

    The American Foulbrood Disease (AFB) is a fatal larval bee infection. The etiologic agent is the bacterium Paenibacillus larvae. The treatment involves incineration of all contaminated materials, leading to high losses. The Glycerol Monolaurate (GML) is a known antimicrobial potential compound, however its use is reduced due to its low solubility in water and high melting point. The nanoencapsulation of some drugs offers several advantages like improved stability and solubility in water. The present study aimed to evaluate the antimicrobial activity against P. larvae and the toxicity in bees of GML nanoparticles. The nanocapsules were produced and presented mean diameter of 210 nm, polydispersity index of 0.044, and zeta potential of -23.4 mV demonstrating the acceptable values to predict a stable system. The microdilution assay showed that it is necessary 142 and 285 μg/mL of GML nanocapsules to obtain a bacteriostatic and bactericidal effect respectively. The time-kill curve showed the controlled release of compound, exterminating the microorganism after 24 h. The GML nanocapsules were able to kill the spore form of Paenibacillus larvae while the GML do not cause any effect. The assay in bees showed that the GML has a high toxicity while the GML nanoparticles showed a decrease on toxic effects. Concluding, the formulation shows positive results in the action to combat AFB besides not causing damage to bees.

  13. Spray-dried powders improve the controlled release of antifungal tioconazole-loaded polymeric nanocapsules compared to with lyophilized products.

    PubMed

    Ribeiro, Roseane Fagundes; Motta, Mariana Heldt; Härter, Andréia Pisching Garcia; Flores, Fernanda Cramer; Beck, Ruy Carlos Ruver; Schaffazick, Scheila Rezende; de Bona da Silva, Cristiane

    2016-02-01

    This work aimed to obtain solid formulations from polymeric nanocapsules and nanoemulsions containing tioconazole, a broad spectrum antifungal drug. Two dehydration methods were used: spray-drying and freeze drying, using lactose as adjuvant (10%, w/v). The liquid formulations had a mean particle size around 206 nm and 182 nm for nanocapsules and nanoemulsions, respectively, and an adequate polydispersity index. Tioconazole content was close to the theoretical amount (1.0 mg/mL). After drying, the content ranged between 98 and 102%with a mean nanometric size of the dried products after redispersion. Scanning electron microscopy showed that the particles are rounded, sphere-shaped for the dried products obtained by spray-drying, and shapeless and irregular shapes for those obtained by freeze-drying. In the microbiological evaluation, all dried products remained active against the yeast Candida albicans when compared to the original systems. The dried products obtained by spray-drying from nanocapsules presented better control of the tioconazole release when compared to the freeze-drying products.

  14. Inclusion of Zinc Oxide Nanoparticles into Virus-Like Peptide Nanocapsules Self-Assembled from Viral β-Annulus Peptide

    PubMed Central

    Fujita, Seiya; Matsuura, Kazunori

    2014-01-01

    A viral β-annulus peptide connected with a zinc oxide (ZnO)-binding sequence (HCVAHR) at its N-terminal was synthesized, and the inclusion behavior of quantum-sized ZnO nanoparticles into the peptide nanocapsules formed by self-assembly of the peptide in water was investigated. Dynamic light scattering (DLS) measurements showed that ZnO nanoparticles (approximately 10 nm) in the presence of the peptide (0.1 mM) formed assemblies with an average size of 48 ± 24 nm, whereas ZnO nanoparticles in the absence of the peptide formed large aggregates. Transmission electron microscopy (TEM) observations of the ZnO nanoparticles in the presence of the peptide revealed that ZnO nanoparticles were encapsulated into the peptide nanocapsules with a size of approximately 50 nm. Fluorescence spectra of a mixture of the peptide and ZnO nanoparticles suggested that the ZnO surface and the peptide interact. Template synthesis of ZnO nanoparticles with the peptide nanocapsules afforded larger nanoparticles (approximately 40 nm), which are not quantum-sized ZnO.

  15. Effects of Ultrasound Irradiation on the Release Profile of 5-fluorouracil from Magnetic Polylactic co-glycolic Acid Nanocapsules

    PubMed Central

    Abed, Z.; Beik, J.; Khoee, S.; Khoei, S.; Shakeri-Zadeh, A.; Shiran, M.B.

    2016-01-01

    Background: Drug nano-carriers are one of the most important tools for targeted cancer therapy so that undesired side effects of chemotherapy drugs are minimized. In this area, the use of ultrasound can be helpful in controlling drug release from nanoparticles to achieve higher treatment efficiency. Objective: Here, we studies the effects of ultrasound irradiation on the release profile of 5-fluorouracil (5-Fu) loaded magnetic poly lactic co-glycolic acid (PLGA) nanocapsules. Methods: 5-Fu loaded magnetic PLGA nanocapsules were synthesized by multiple emulsification method. Particle size was measured by dynamic light scattering (DLS) and transmission electron microscope (TEM). The pattern of drug release was assessed with and without 3 MHz ultrasound waves at intensities of 0.3, 0.5 and 1 w/cm2 for exposure time of 5 and 10 min in phosphate-buffered saline (PBS). Results: The size of nanoparticles was about 70 nm. Electron microscope images revealed the spherical shape of nanoparticles. The results demonstrated that the intensity and exposure time of ultrasound irradiation have significant effects on the profile of drug release from nanoparticles. Conclusion: It may be concluded that the application of ultrasound to control the release profile of drug loaded nanocapsules would be a promising method to develop a controlled drug delivery strategy in cancer therapy. PMID:27853726

  16. Stimuli-responsive protamine-based biodegradable nanocapsules for enhanced bioavailability and intracellular delivery of anticancer agents

    NASA Astrophysics Data System (ADS)

    Radhakrishnan, Krishna; Thomas, Midhun B.; Pulakkat, Sreeranjini; Gnanadhas, Divya P.; Chakravortty, Dipshikha; Raichur, Ashok M.

    2015-08-01

    Enzyme- and pH-responsive polyelectrolyte nanocapsules having diameters in the range of 200 ± 20 nm were fabricated by means of Layer-by-Layer assembly of biopolymers, protamine, and heparin, and then loaded with anticancer drug doxorubicin. The incorporation of the FDA-approved peptide drug protamine as a wall component rendered the capsules responsive to enzyme stimuli. The stimuli-responsive drug release from these nanocapsules was evaluated, and further modulation of capsule permeability to avoid premature release was demonstrated by crosslinking the wall components. The interaction of the nanocapsules with cancer cells was studied using MCF-7 breast cancer cells. These capsules were readily internalized and disintegrated inside the cells, culminating in the release of the loaded doxorubicin and subsequent cell death as observed by confocal microscopy and MTT Assay. The bioavailability studies performed using BALB/c mice revealed that the encapsulated doxorubicin exhibited enhanced bioavailability compared to free doxorubicin. Our results indicate that this stimuli-responsive system fabricated from clinically used FDA-approved molecules and exhibiting minimal premature release has great potential for drug-delivery applications.

  17. n-Alkanes and polynuclear aromatic hydrocarbons in fresh-forzen and precooked-frozen mussels

    SciTech Connect

    Hernandez, J.E.; Machado, L.T.; Corbella, R.

    1995-09-01

    Heavy oil pollution has been found in sea water and coastal environments not only near industrial petroleum districts and places of oil spillage but also in other places where crude oil and/or refined products can be carried to by winds, streams, etc. Marine oil pollution may not only affect productivity and quality of marine organisms but may ultimately affect the health of the human population as there is a possible health risk from consumption of sea food contaminated by oil-derived carcinogens such as polycyclic aromatic hydrocarbons (PAHs). In the marine habitat, many organisms readily accumulate n-alkanes and PAHs from the environment and store them at a relatively high level in their tissues, and studies have been carried out on the accumulation and depuration of toxic organic pollutants in marine organisms. As a part of a continuous monitoring program of the foods imported to the Canary Islands this paper presents the results obtained in the determination of n-alkanes and PAHs in fresh-frozen and precooked-frozen mussels, Perna canaliculus, commercialized in these islands. 9 refs., 2 figs., 5 tabs.

  18. Soil organic matter mineralization in frozen soils

    NASA Astrophysics Data System (ADS)

    Harrysson Drotz, S.; Sparrman, T.; Schleucher, J.; Nilsson, M.; Öquist, M. G.

    2009-12-01

    Boreal forest soils are frozen for a large part of the year and soil organic matter mineralization during this period has been shown to significantly influence the C balance of boreal forest ecosystems. Mineralization proceeds through heterotrophic microbial activity, but the understanding of the environmental controls regulating soil organic matter mineralization under frozen conditions is poor. Through a series of investigations we have addressed this issue in order to elucidate to what extent a range of environmental factors control mineralization processes in frozen soils and also the microbial communities potential to oxidize organic substrates and grow under such conditions. The unfrozen water content in the frozen soils was shown to be an integral control on the temperature response of biogenic CO2 production across the freezing point of bulk soil water. We found that osmotic potential was an important contributor to the total water potential and, hence, the unfrozen water content of frozen soil. From being low and negligible in an unfrozen soil, the osmotic potential was found to contribute up to 70% of the total water potential in frozen soil, greatly influencing the volume of liquid water. The specific factors of how soil organic matter composition affected the unfrozen water content and CO2 production of frozen soil were studied by CP-MAS NMR. We concluded that abundance of aromatics and recalcitrant compounds showed a significant positive correlation with unfrozen water content and these were also the major soil organic fractions that similarly correlated with the microbial CO2 production of the frozen soils. Thus, the hierarchy of environmental factors controlling SOM mineralization changes as soils freeze and environmental controls elucidated from studies of unfrozen systems can not be added on frozen conditions. We have also investigated the potential activity of soil microbial communities under frozen conditions in order to elucidate temperature

  19. Preference mapping of frozen and fresh raspberries.

    PubMed

    Villamor, R R; Daniels, C H; Moore, P P; Ross, C F

    2013-06-01

    The purpose of the study was to identify key sensory attributes that influence consumer liking for frozen and fresh red raspberries using preference mapping. Sensory profiling of different raspberry cultivars and selections from the Washington State Univ. and Oregon State Univ. breeding programs was carried out using a trained panel (frozen, n = 12 and fresh, n = 10). In addition, a subset of frozen and fresh raspberries of each cultivar was assessed by consumers for sensory acceptability (n = 105 and n = 100, respectively). Based on overall hedonic ratings, cluster analysis identified 3 clusters of frozen raspberry consumers from day 1 (41% "nondistinguishers," 34% "likers," and 25% "nonlikers") and day 2 (41% "group 1 likers," 26% "nonlikers," and 34% and 33% group 2 likers"). For fresh raspberry consumers, 2 clusters were detected from day 1 (54% "likers" and 46% nondistinguishers") and day 2 (54% "group 1 likers" and 46% "group 2 likers"). Preference mapping was applied on the descriptive sensory and acceptability of clustered consumer data. Partial least squares regression results showed that liking of frozen raspberries was driven by high raspberry flavor, firmness, and sweetness. Conversely, disliking of frozen raspberries was related to high sour and aftertaste intensity. In the case of fresh raspberries, high color uniformity, raspberry aroma, raspberry flavor, floral aroma, green flavor, bitter, astringency, and aftertaste increased the acceptability, whereas high color intensity and green aroma were associated with negative drivers of liking. The information obtained in this study can be a useful guide for breeders in the selection of characteristics for growing superior quality raspberries. © 2013 Institute of Food Technologists®

  20. Albumin nanocapsules containing fenretinide: pre-clinical evaluation of cytotoxic activity in experimental models of human non-small cell lung cancer.

    PubMed

    Pignatta, Sara; Orienti, Isabella; Falconi, Mirella; Teti, Gabriella; Arienti, Chiara; Medri, Laura; Zanoni, Michele; Carloni, Silvia; Zoli, Wainer; Amadori, Dino; Tesei, Anna

    2015-02-01

    The present study deals with the preparation of albumin nanocapsules containing fenretinide and their evaluation in experimental models of human non-small cell lung cancer. These nanocapsules showed enhanced antitumor activity with respect to free fenretinide due to the solubilization effect of albumin on the hydrophobic drug, known to improve bioavailability. The high expression of caveolin-1 on the A549 cell surface further enhanced the antitumor activity of the nanoencapsulated fenretinide. Caveolin-1 favored albumin uptake and improved the efficacy of the fenretinide-loaded albumin nanocapsules, especially in 3-D cultures where the densely packed 3-D structures impaired drug diffusibility and severely reduced the activity of the free drug. The efficacy of the fenretinide albumin nanocapsules was further confirmed in tumor xenograft models of A549 by the significant delay in tumor progression observed with respect to control after intravenous administration of the novel formulation. This study describes the preparation of fenretinide containing albumin nanocapsules and their evaluation in experimental models of non-small cell lung cancer, showing enhanced antitumor activity compared to free fenretinide. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Phase-Shifted PFH@PLGA/Fe3O4 Nanocapsules for MRI/US Imaging and Photothermal Therapy with near-Infrared Irradiation.

    PubMed

    Zhao, Yajing; Song, Weixiang; Wang, Dong; Ran, Haitao; Wang, Ronghui; Yao, Yuanzhi; Wang, Zhigang; Zheng, Yuanyi; Li, Pan

    2015-07-08

    Photothermal therapy (PTT) utilizes photothermal conversion reagents to generate heat energy from absorbed light to effectively treat various malignant diseases. This approach has attracted broad and increasing interest in cancer treatment. Near-infrared (NIR)-induced PTT is particularly attractive because of its minimal absorbance by normal tissue and relatively deep tissue penetration. To improve the efficacy of PTT, we have developed nanocapsules encapsulating superparamagnetic iron oxide (Fe3O4) as synergistic agents for NIR-induced PTT. In this study, phase-shift and NIR photoabsorbing poly(lactic-co-glycolic acid) (PLGA) nanocapsules (perfluorohexane (PFH)@PLGA/Fe3O4) were fabricated for MRI/US dual-modal imaging-guided PTT. The multifunctional nanocapsules can be used not only to increase the local tumor temperature by absorbing the NIR energy but also as bimodal contrast agents for both MRI and US imaging. Such nanocapsules can be converted into microbubbles under NIR irradiation, which produces excellent contrast for US imaging and enhanced cancer ablation. We refer to the nanocapsule phase transition process induced by the infrared lamp as NIR radiation droplet vaporization (NIRDV).

  2. The effect of refrigerated and frozen storage on butter flavor and texture.

    PubMed

    Krause, A J; Miracle, R E; Sanders, T H; Dean, L L; Drake, M A

    2008-02-01

    Butter is often stored for extended periods of time; therefore, it is important for manufacturers to know the refrigerated and frozen shelf life. The objectives of this study were to characterize the effect of refrigerated and frozen storage on the sensory and physical characteristics of butter. Fresh butter was obtained on 2 occasions from 2 facilities in 113-g sticks and 4-kg bulk blocks (2 facilities, 2 package forms). Butters were placed into both frozen (-20 degrees C) and refrigerated storage (5 degrees C). Frozen butters were sampled after 0, 6, 12, 15, and 24 mo; refrigerated butters were sampled after 0, 3, 6, 9, 12, 15, and 18 mo. Every 3 mo, oxidative stability index (OSI) and descriptive sensory analysis (texture, flavor, and color) were conducted. Every 6 mo, peroxide value (PV), free fatty acid value (FFV), fatty acid profiling, vane, instrumental color, and oil turbidity were examined. A mixed-model ANOVA was conducted to characterize the effects of storage time, temperature, and package type. Storage time, temperature, and package type affected butter flavor, OSI, PV, and FFV. Refrigerated butter quarters exhibited refrigerator/stale off-flavors concurrent with increased levels of oxidation (lower oxidative stability and higher PV and FFV) within 6 mo of refrigerated storage, and similar trends were observed for refrigerated bulk butter after 9 mo. Off-flavors were not evident in frozen butters until 12 or 18 mo for quarters and bulk butters, respectively. Off-flavors in frozen butters were not correlated with instrumental oxidation measurements. Because butter is such a desirable fat source in terms of flavor and textural properties, it is important that manufacturers understand how long their product can be stored before negative attributes develop.

  3. Monitoring pH-Triggered Drug Release from Radioluminescent Nanocapsules with X-Ray Excited Optical Luminescence

    PubMed Central

    Chen, Hongyu; Moore, Thomas; Qi, Bin; Colvin, Daniel C.; Jelen, Erika K.; Hitchcock, Dale A.; He, Jian; Mefford, O. Thompson; Gore, John C.; Alexis, Frank; Anker, Jeffrey N.

    2013-01-01

    One of the greatest challenges in cancer therapy is to develop methods to deliver chemotherapy agents to tumor cells while reducing systemic toxicity to non-cancerous cells. A promising approach to localizing drug release is to employ drug-loaded nanoparticles with coatings that release the drugs only in the presence of specific triggers found in the target cells such as pH, enzymes, or light. However, many parameters affect the nanoparticle distribution and drug release rate and it is difficult to quantify drug release in situ. In this work, we show proof of principle for a “smart” radioluminescent nanocapsule with X-ray excited optical luminescence (XEOL) spectrum that changes during release of the optically absorbing chemotherapy drug, doxorubicin. XEOL provides an almost background-free luminescent signal for measuring drug release from particles irradiated by a narrow X-ray beam. We study in vitro pH triggered release rates of doxorubicin from nanocapsules coated with a pH responsive polyelectrolyte multilayer using HPLC and XEOL spectroscopy. The doxorubicin was loaded to over 5 % by weight, and released from the capsule with a time constant in vitro of ~ 36 days at pH 7.4, and 21.4 hr at pH 5.0, respectively. The Gd2O2S:Eu nanocapsules are also paramagnetic at room temperature with similar magnetic susceptibility and similarly good MRI T2 relaxivities to Gd2O3, but the sulfur increases the radioluminescence intensity and shifts the spectrum. Empty nanocapsules did not affect cell viability up to concentrations of at least 250 μ/ml. These empty nanocapsules accumulated in a mouse liver and spleen following tail vein injection, and could be observed in vivo using XEOL. The particles are synthesized with a versatile template synthesis technique which allows for control of particle size and shape. The XEOL analysis technique opens the door to non-invasive quantification of drug release as a function of nanoparticle size, shape, surface chemistry and tissue

  4. p,p'-Methoxyl-diphenyl diselenide-loaded polymeric nanocapsules as a novel approach to inflammatory pain treatment: Behavioral, biochemistry and molecular evidence.

    PubMed

    Marcondes Sari, Marcel Henrique; Zborowski, Vanessa Angonesi; Ferreira, Luana Mota; Jardim, Natália Silva; Barbieri, Allanna Valentini; Cruz, Letícia; Nogueira, Cristina Wayne

    2017-09-22

    The current study investigated the effect of organoselenium compound p,p'-methoxyl-diphenyl diselenide [(OMePhSe)2], free or incorporated into nanocapsules, on behavioral, biochemical and molecular alterations in an inflammatory pain model induced by complete Freund's adjuvant (CFA). Male Swiss mice received an intraplantar injection of CFA in the hindpaw and 24 h later they were treated via the intragastric route with a single (OMePhSe)2 administration, in its free form (dissolved in canola oil) or (OMePhSe)2 NC. The anti-hypernociceptive time- and dose-response curves were carried out using the von Frey hair test. Biochemical and histological parameters were determined in samples of injected paws and those of cerebral contralateral cortex were collected to determine immuno content of inflammatory proteins. Both (OMePhSe)2 forms reduced the hypernociception induced by CFA as well as attenuated the altered parameters of the inflammatory process in the paw (paw edema, myeloperoxidase and histological). However, the (OMePhSe)2 NC had a more prolonged anti-hypernociceptive action (7h) at a lower dose (10mg/kg) and superior effects on the paw alterations than the free compound form (4h and 25mg/kg). Furthermore, independent of the (OMePhSe)2 form, its administration decreased the MAPKs pathway activation (JNK;ERK1,2; p38) as well as iNOS, COX-2, Nf-κB and IL-1β protein contents in the cerebral contralateral cortex that were increased by paw CFA injection. Therefore, (OMePhSe)2 NC had superior anti-inflammatory action, which possibly occurs by the inflammatory protein content modulation and also attenuates paw biochemical and histological inflammatory alterations induced by CFA injection. Copyright © 2017. Published by Elsevier B.V.

  5. Exclusion of Nitrate from Frozen Aqueous Solutions

    NASA Astrophysics Data System (ADS)

    Marrocco, H. A.; Michelsen, R. R.

    2013-12-01

    Reactions occurring at the surface of ice, sea ice, and snow in Earth's cryosphere have an impact on the composition of the overlying atmosphere. In order to elucidate reaction mechanisms and model their contributions to atmospheric processes, the morphology of frozen aqueous surfaces and amounts of reactants contained therein must be determined. To this end, the exclusion of nitrate ions to the surface of frozen aqueous solutions has been studied by attenuated total reflection infrared spectroscopy (ATR-IR). In this technique the near-surface region of the frozen films are interrogated to a depth of a few hundred nanometers from the film-crystal interface. Aqueous solutions (0.001 to 0.01 M) of sodium nitrate (NaNO3), magnesium nitrate (Mg(NO3)2), and nitric acid (HNO3) were quickly frozen on the germanium ATR crystal and observed at a constant temperature of about -18°C. In addition to ice and the solutes, liquid water in varying amounts was observed in the spectra. The amount of nitrate in the surface liquid is three to four orders of magnitude higher than in the unfrozen solution. While all the nitrate salts exhibit exclusion to the unfrozen surface, the dynamics are different for different counter-ions. Results are compared to freezing point depression data and the predictions of equilibrium thermodynamics.

  6. Frozen yogurt with added inulin and isomalt.

    PubMed

    Isik, U; Boyacioglu, D; Capanoglu, E; Erdil, D Nilufer

    2011-04-01

    The objective of this study was to produce a frozen yogurt containing low fat and no added sugar. Samples containing 5% polydextrose, 0.065% aspartame and acesulfame-K mixture, and different levels of inulin and isomalt (5.0, 6.5, and 8.0%) were produced at pilot scale and analyzed for their physical and chemical properties including proximate composition, viscosity, acidity, overrun, melting rate, heat shock stability, as well as sensory characteristics, and viability of lactic acid bacteria. With the addition of inulin and isomalt, viscosity increased by 19 to 52% compared with that of sample B (reduced-fat control). The average calorie values of samples substituted with sweeteners were about 43% lower than that of original sample. Low-calorie frozen yogurt samples melted about 33 to 48% slower than the reduced-fat control sample at 45 min. Based on quantitative descriptive profile test results, statistically significant differences among products were observed for hardness, iciness, foamy melting, whey separation, and sweetness characteristics. The results of principal component analysis showed that the sensory properties of the sample containing 6.5% inulin and 6.5% isomalt were similar to those of control. Lactic acid bacteria counts of frozen yogurt were found to be between 8.12 and 8.49 log values, 3 mo after the production. The overall results showed that it is possible to produce an attractive frozen yogurt product with the incorporation of inulin and isomalt with no added sugar and reduced fat.

  7. Frozen water waves over rough topographical bottoms.

    PubMed

    Chen, Liang-Shan; Ye, Zhen

    2004-09-01

    The propagation of surface water waves over rough topographical bottoms is investigated by the multiple scattering theory. It is shown that the waves can be localized spatially through the process of multiple scattering and wave interference, a peculiar wave phenomenon which has been previously discussed for frozen light in optical systems [Nature 390, 661 (1997)

  8. Sewage Effluent Infiltrates Frozen Forest Soil

    Treesearch

    Alfred Ray Harris

    1976-01-01

    Secondarily treated sewage effluent, applied at the rate of 1 and 2 inches per week, infiltrated a frozen Sparta sand soil forested with jack pine and scrub oak. Maximum frost depth in treated plots averaged 60 cm and in check plots averages 35 cm. Nitrogen was mobile with some accumulation. Phosphorus was absorbed.

  9. Using frozen sugarcane for alcohol production

    SciTech Connect

    Irvine, J.E.

    1980-01-01

    The three areas that produce sugarcane in the mainland US are subject to crop-damaging freezes. Florida has fewer freezes. Texas and Louisiana are hurt frequently. Hard freezes end processing for sugar production when dextrans form and prevent crystallization. Dextran is formed from sugar by bacteria. Work at the Audubon Sugar Institute, LSU, has shown that crystallization of sucrose can be achieved with juice from frozen sugarcane when enzymes are used to reduce the size of the dextran molecule. Frozen cane may also be processed for alcohol production. How long the cane would be suitable as feedstock was questioned; its use would depend on sugar content. Sugarcane has been tested for post-freeze deterioration at the US Sugarcane Field Laboratory for over 50 years, and the emphasis has been on the response of varieties selected for sugar production in post-freeze deterioration. The data indicated that juice from frozen sugarcane in any of the tests would be adequate for alcohol production; fermentation based on mash with a sugar content of 9 to 11% for rum, and 15% for industrial alcohol. Total fermentable carbohydrates in frozen cane would be even higher since the data did not include invert sugars or starch. 1 table. (DP)

  10. 7 CFR 58.349 - Frozen cream.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Products Bearing Usda Official Identification § 58.349 Frozen cream. The flavor shall be sweet, pleasing and desirable, but may possess the following flavors to a slight degree: Aged, bitter, flat, smothered, storage; and cooked and feed flavors to a definite degree. It shall be free from rancid, oxidized or...

  11. Graphene Oxide and Gadolinium-Chelate Functionalized Poly(lactic acid) Nanocapsules Encapsulating Perfluorooctylbromide for Ultrasound/Magnetic Resonance Bimodal Imaging Guided Photothermal Ablation of Cancer.

    PubMed

    Li, Zhenglin; Ke, Hengte; Wang, Jinrui; Miao, Zhaohua; Yue, Xiuli

    2016-03-01

    This paper successfully fabricated a novel multifunctional theranostic agent (PFOB@PLA/GO/Gd-DTPA NCs) by loading perfluorooctylbromide (PFOB) into poly(lactic acid) (PLA) nanocapsules (NCs) followed by surface functionalization with graphene oxide (GO) and gadolinium-chelate (Gd-DTPA). It was found that the resulting nanoagent could serve as a contrast agent simultaneously to enhance ultrasound (US) and magnetic resonance imaging (MRI). Benefiting from the strong absorption in the near infrared (NIR) region, the nanocapsules could efficiently kill cancer cells under NIR laser irradiation. Thus, such a single theranostic agent with the combination of realtime US imaging and high-resolution MR imaging could achieve great therapeutic effectiveness without systemic damage to the body. In addition, the cytotoxicity assay on HUVEC cells revealed a good biocompatibility of PFOB@PLA/GO/Gd-DTPA NCs, showing that the versatile nanocapsule system may hold great potential as an effective nanoplatform for contrast enhanced imaging guided photothermal therapy.

  12. Comparison of treatments to inactivate viral hemorrhagic septicemia virus (VHSV-IVb) in frozen baitfish.

    PubMed

    Phelps, Nicholas B D; Goodwin, Andrew E; Marecaux, Emily; Goyal, Sagar M

    2013-02-28

    Current US state and federal fish health regulations target the spread of viral hemorrhagic septicemia virus-IVb (VHSV-IVb) through movement restrictions of live fish; however, they largely ignore the potential for the virus to be spread through commercial distribution and use of frozen baitfish from VHSV-IVb-positive regions. Some state laws do require treatment of frozen baitfish to inactivate VHSV, and additional methods have been proposed, but few scientific studies have examined the efficacy of these treatments. In this study, bluegills Lepomis macrochirus were challenged with VHSV-IVb and frozen to represent standard industry methods, disinfected by various treatments, and tested for infectious VHSV-IVb using virus isolation. The virus was isolated from 70% of fish subjected to 3 freeze/thaw cycles. All other treatment methods were effective in inactivating the virus, including treatment with isopropyl alcohol, mineral oil, salt and borax, and dehydration. Dehydration followed by rehydration is rapid and effective, and therefore, seems to be the best option for inactivating VHSV-IVb present in frozen baitfish while maintaining their usefulness as bait.

  13. Novel therapeutic mechanisms determine the effectiveness of lipid-core nanocapsules on melanoma models

    PubMed Central

    Drewes, Carine C; Fiel, Luana A; Bexiga, Celina G; Asbahr, Ana Carolina C; Uchiyama, Mayara K; Cogliati, Bruno; Araki, Koiti; Guterres, Sílvia S; Pohlmann, Adriana R; Farsky, Sandra P

    2016-01-01

    Melanoma is a severe metastatic skin cancer with poor prognosis and no effective treatment. Therefore, novel therapeutic approaches using nanotechnology have been proposed to improve therapeutic effectiveness. Lipid-core nanocapsules (LNCs), prepared with poly(ε-caprolactone), capric/caprylic triglyceride, and sorbitan monostearate and stabilized by polysorbate 80, are efficient as drug delivery systems. Here, we investigated the effects of acetyleugenol-loaded LNC (AcE-LNC) on human SK-Mel-28 melanoma cells and its therapeutic efficacies on melanoma induced by B16F10 in C57B6 mice. LNC and AcE-LNC had z-average diameters and zeta potential close to 210 nm and -10.0 mV, respectively. CytoViva® microscopy images showed that LNC and AcE-LNC penetrated into SK-Mel-28 cells, and remained in the cytoplasm. AcE-LNC in vitro treatment (18–90×109 particles/mL; 1 hour) induced late apoptosis and necrosis; LNC and AcE-LNC (3–18×109 particles/mL; 48 hours) treatments reduced cell proliferation and delayed the cell cycle. Elevated levels of nitric oxide were found in supernatant of LNC and AcE-LNC, which were not dependent on nitric oxide synthase expressions. Daily intraperitoneal or oral treatment (days 3–10 after tumor injection) with LNC or AcE-LNC (1×1012 particles/day), but not with AcE (50 mg/kg/day, same dose as AcE-LNC), reduced the volume of the tumor; nevertheless, intraperitoneal treatment caused toxicity. Oral LNC treatment was more efficient than AcE-LNC treatment. Moreover, oral treatment with nonencapsulated capric/caprylic triglyceride did not inhibit tumor development, implying that nanocapsule supramolecular structure is important to the therapeutic effects. Together, data herein presented highlight the relevance of the supramolecular structure of LNCs to toxicity on SK-Mel-28 cells and to the therapeutic efficacy on melanoma development in mice, conferring novel therapeutic mechanisms to LNC further than a drug delivery system. PMID:27099491

  14. Novel therapeutic mechanisms determine the effectiveness of lipid-core nanocapsules on melanoma models.

    PubMed

    Drewes, Carine C; Fiel, Luana A; Bexiga, Celina G; Asbahr, Ana Carolina C; Uchiyama, Mayara K; Cogliati, Bruno; Araki, Koiti; Guterres, Sílvia S; Pohlmann, Adriana R; Farsky, Sandra P

    2016-01-01

    Melanoma is a severe metastatic skin cancer with poor prognosis and no effective treatment. Therefore, novel therapeutic approaches using nanotechnology have been proposed to improve therapeutic effectiveness. Lipid-core nanocapsules (LNCs), prepared with poly(ε-caprolactone), capric/caprylic triglyceride, and sorbitan monostearate and stabilized by polysorbate 80, are efficient as drug delivery systems. Here, we investigated the effects of acetyleugenol-loaded LNC (AcE-LNC) on human SK-Mel-28 melanoma cells and its therapeutic efficacies on melanoma induced by B16F10 in C57B6 mice. LNC and AcE-LNC had z-average diameters and zeta potential close to 210 nm and -10.0 mV, respectively. CytoViva(®) microscopy images showed that LNC and AcE-LNC penetrated into SK-Mel-28 cells, and remained in the cytoplasm. AcE-LNC in vitro treatment (18-90×10(9) particles/mL; 1 hour) induced late apoptosis and necrosis; LNC and AcE-LNC (3-18×10(9) particles/mL; 48 hours) treatments reduced cell proliferation and delayed the cell cycle. Elevated levels of nitric oxide were found in supernatant of LNC and AcE-LNC, which were not dependent on nitric oxide synthase expressions. Daily intraperitoneal or oral treatment (days 3-10 after tumor injection) with LNC or AcE-LNC (1×10(12) particles/day), but not with AcE (50 mg/kg/day, same dose as AcE-LNC), reduced the volume of the tumor; nevertheless, intraperitoneal treatment caused toxicity. Oral LNC treatment was more efficient than AcE-LNC treatment. Moreover, oral treatment with nonencapsulated capric/caprylic triglyceride did not inhibit tumor development, implying that nanocapsule supramolecular structure is important to the therapeutic effects. Together, data herein presented highlight the relevance of the supramolecular structure of LNCs to toxicity on SK-Mel-28 cells and to the therapeutic efficacy on melanoma development in mice, conferring novel therapeutic mechanisms to LNC further than a drug delivery system.

  15. 21 CFR 161.176 - Frozen raw lightly breaded shrimp.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen raw lightly breaded shrimp. 161.176 Section 161.176 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Shellfish § 161.176 Frozen raw lightly breaded shrimp. Frozen raw lightly breaded shrimp complies with...

  16. 7 CFR 58.650 - Requirements for frozen custard.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Requirements for frozen custard. 58.650 Section 58.650... Products Bearing Usda Official Identification § 58.650 Requirements for frozen custard. The same requirements apply as for ice cream except plain frozen custard shall have a minimum egg yolk solids content...

  17. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Frozen processed food... DEPARTMENT SUPPLEMENTARY REGULATIONS SPECIAL PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a label complying with the Federal...

  18. 48 CFR 846.302-72 - Frozen processed foods.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Frozen processed foods... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 846.302-72 Frozen processed foods. The contracting officer shall insert the clause at 852.246-72, Frozen processed foods, in solicitations and contracts for...

  19. 48 CFR 852.246-72 - Frozen processed foods.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Frozen processed foods. 852.246-72 Section 852.246-72 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... Frozen processed foods. As prescribed in 846.302-72, insert the following clause: Frozen Processed Foods...

  20. 48 CFR 846.302-72 - Frozen processed foods.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Frozen processed foods... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 846.302-72 Frozen processed foods. The contracting officer shall insert the clause at 852.246-72, Frozen processed foods, in solicitations and contracts for...

  1. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Frozen processed food... DEPARTMENT SUPPLEMENTARY REGULATIONS SPECIAL PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a label complying with the Federal...

  2. 48 CFR 852.246-72 - Frozen processed foods.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Frozen processed foods. 852.246-72 Section 852.246-72 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... Frozen processed foods. As prescribed in 846.302-72, insert the following clause: Frozen Processed Foods...

  3. 21 CFR 146.146 - Frozen concentrated orange juice.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Frozen concentrated orange juice. 146.146 Section... Fruit Juices and Beverages § 146.146 Frozen concentrated orange juice. (a) Frozen concentrated orange juice is the food prepared by removing water from the juice of mature oranges as provided in §...

  4. 21 CFR 146.146 - Frozen concentrated orange juice.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Frozen concentrated orange juice. 146.146 Section... Fruit Juices and Beverages § 146.146 Frozen concentrated orange juice. (a) Frozen concentrated orange juice is the food prepared by removing water from the juice of mature oranges as provided in §...

  5. 21 CFR 146.146 - Frozen concentrated orange juice.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Frozen concentrated orange juice. 146.146 Section... Fruit Juices and Beverages § 146.146 Frozen concentrated orange juice. (a) Frozen concentrated orange juice is the food prepared by removing water from the juice of mature oranges as provided in §...

  6. 21 CFR 146.146 - Frozen concentrated orange juice.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Frozen concentrated orange juice. 146.146 Section... Fruit Juices and Beverages § 146.146 Frozen concentrated orange juice. (a) Frozen concentrated orange juice is the food prepared by removing water from the juice of mature oranges as provided in §...

  7. 21 CFR 146.146 - Frozen concentrated orange juice.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen concentrated orange juice. 146.146 Section... Fruit Juices and Beverages § 146.146 Frozen concentrated orange juice. (a) Frozen concentrated orange juice is the food prepared by removing water from the juice of mature oranges as provided in §...

  8. 48 CFR 846.302-72 - Frozen processed foods.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Frozen processed foods... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 846.302-72 Frozen processed foods. The contracting officer shall insert the clause at 852.246-72, Frozen processed foods, in solicitations and contracts...

  9. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Frozen processed food... DEPARTMENT SUPPLEMENTARY REGULATIONS SPECIAL PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a label complying with the...

  10. 48 CFR 852.246-72 - Frozen processed foods.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Frozen processed foods. 852.246-72 Section 852.246-72 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... Frozen processed foods. As prescribed in 846.302-72, insert the following clause: Frozen Processed...

  11. 48 CFR 852.246-72 - Frozen processed foods.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Frozen processed foods. 852.246-72 Section 852.246-72 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... Frozen processed foods. As prescribed in 846.302-72, insert the following clause: Frozen Processed...

  12. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Frozen processed food... DEPARTMENT SUPPLEMENTARY REGULATIONS SPECIAL PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a label complying with the...

  13. 48 CFR 846.302-72 - Frozen processed foods.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Frozen processed foods... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 846.302-72 Frozen processed foods. The contracting officer shall insert the clause at 852.246-72, Frozen processed foods, in solicitations and contracts...

  14. 48 CFR 852.246-72 - Frozen processed foods.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Frozen processed foods. 852.246-72 Section 852.246-72 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... Frozen processed foods. As prescribed in 846.302-72, insert the following clause: Frozen Processed...

  15. 48 CFR 846.302-72 - Frozen processed foods.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Frozen processed foods... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 846.302-72 Frozen processed foods. The contracting officer shall insert the clause at 852.246-72, Frozen processed foods, in solicitations and contracts...

  16. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... DEPARTMENT SUPPLEMENTARY REGULATIONS SPECIAL PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a label complying with the Federal... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Frozen processed...

  17. 21 CFR 146.120 - Frozen concentrate for lemonade.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... lemonade is the frozen food prepared from one or both of the lemon juice ingredients specified in paragraph... percent by weight. (b) The lemon juice ingredients referred to in paragraph (a) of this section are: (1) Lemon juice or frozen lemon juice or a mixture of these. (2) Concentrated lemon juice or frozen...

  18. 21 CFR 161.176 - Frozen raw lightly breaded shrimp.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Frozen raw lightly breaded shrimp. 161.176 Section... Shellfish § 161.176 Frozen raw lightly breaded shrimp. Frozen raw lightly breaded shrimp complies with the provisions of § 161.175, except that it contains not less than 65 percent of shrimp material, as...

  19. 21 CFR 161.176 - Frozen raw lightly breaded shrimp.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Frozen raw lightly breaded shrimp. 161.176 Section... Shellfish § 161.176 Frozen raw lightly breaded shrimp. Frozen raw lightly breaded shrimp complies with the provisions of § 161.175, except that it contains not less than 65 percent of shrimp material, as...

  20. 21 CFR 161.176 - Frozen raw lightly breaded shrimp.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Frozen raw lightly breaded shrimp. 161.176 Section... Shellfish § 161.176 Frozen raw lightly breaded shrimp. Frozen raw lightly breaded shrimp complies with the provisions of § 161.175, except that it contains not less than 65 percent of shrimp material, as...

  1. 21 CFR 161.176 - Frozen raw lightly breaded shrimp.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Frozen raw lightly breaded shrimp. 161.176 Section... Shellfish § 161.176 Frozen raw lightly breaded shrimp. Frozen raw lightly breaded shrimp complies with the provisions of § 161.175, except that it contains not less than 65 percent of shrimp material, as...

  2. Frozen O2 layer revealed by neutron reflectometry

    DOE PAGES

    Steffen, A.; Glavic, A.; Holderer, O.; ...

    2016-05-27

    We investigated a 63 thick film originating from frozen air on a solid substrate via neutron reflectometry. Furthermore, the experiment shows that neutron reflectometry allows performing chemical surface analysis by quantifying the composition of this frozen layer and identifies the film to be frozen oxygen.

  3. 21 CFR 135.110 - Ice cream and frozen custard.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Ice cream and frozen custard. 135.110 Section 135.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION FROZEN DESSERTS Requirements for Specific Standardized Frozen Desserts § 135...

  4. 21 CFR 135.110 - Ice cream and frozen custard.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Ice cream and frozen custard. 135.110 Section 135.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION FROZEN DESSERTS Requirements for Specific Standardized Frozen Desserts § 135...

  5. 21 CFR 135.110 - Ice cream and frozen custard.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Ice cream and frozen custard. 135.110 Section 135.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION FROZEN DESSERTS Requirements for Specific Standardized Frozen Desserts § 135...

  6. 21 CFR 135.110 - Ice cream and frozen custard.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Ice cream and frozen custard. 135.110 Section 135.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION FROZEN DESSERTS Requirements for Specific Standardized Frozen Desserts § 135...

  7. Production of Carbon Clusters by Means of Arc Discharge and Their Application 3.Carbon Nanotubes and Nanocapsules Produced by Arc Discharge and their Applications

    NASA Astrophysics Data System (ADS)

    Saito, Yahachi

    This paper characterizes and describes the growth of carbon nanotubes (multiwall and single-wall) and nanocapsules produced by electric arc discharge. For the preparation of multiwall nanotubes, an electrode of pure carbon is evaporated in helium gas, while single-wall nanotubes are produced with the aid of metal catalysts. When carbon is evaporated together with metals, carbon nanocages filled with fine metal particles (called “nanocapsules”) are produced in addition to single-wall nanotubes. The growth of nanotubes and nanocapsules is discussed. Finally, the application of nanotubes in a field emission electron source (cold cathode) is demonstrated.

  8. Batch testing for noroviruses in frozen raspberries.

    PubMed

    De Keuckelaere, Ann; Li, Dan; Deliens, Bart; Stals, Ambroos; Uyttendaele, Mieke

    2015-01-02

    Berries, in particular raspberries, have been associated with multiple recalls due to norovirus contamination and were linked to a number of norovirus (NoV) outbreaks. In the present study a total of 130 samples of frozen raspberries were collected from 26 batches in four different raspberry processing companies. In two companies the samples consisted of bulk frozen raspberries serving as raw material for the production of raspberry puree (an intermediate food product in a business to business setting). In two other companies, the samples consisted of bulk individually quick frozen (IQF) raspberries serving as raw material for the production of frozen fruit mixes (as a final food product for consumer). Enumeration of Escherichia coli and coliforms was performed as well as real-time reverse transcription PCR (RT-qPCR) detection of GI and GII NoV (in 2 × 10 g). In addition, in cases where positive NoV GI or GII RT-qPCR signals were obtained, an attempt to sequence the amplicons was undertaken. Six out of 70 samples taken from the 14 batches of frozen raspberries serving raspberry puree production provided a NoV RT-qPCR signal confirmed by sequencing. Four of these six positive samples clustered in one batch whereas the other two positive samples clustered in another batch from the same company. All six positive samples showed NoV RT-qPCR signals above the limit of quantification of the RT-qPCR assay. These two positive batches of frozen raspberries can be classified as being of insufficient sanitary quality. The mean NoV level in 20 g of these raspberry samples was 4.3 log genomic copies NoV GI/20 g. The concern for public health is uncertain as NoV RT-qPCR detection is unable to discriminate between infectious and non-infectious virus particles. For the IQF raspberries, one batch out of 12 tested NoV positive, but only 1 out of the 5 samples analyzed in this batch showed a positive RT-qPCR GI NoV signal confirmed by sequencing. The RT-qPCR signal was below the

  9. Optimization of in vitro release of an anticonvulsant using nanocapsule-based thermogels.

    PubMed

    Esmaeili, Akbar; Singh, Sonia

    2017-03-01

    Controlling the release rate of anticonvulsant drugs can have a significant effect on the efficacy of these drugs and the safety with which they can be administered to patients. This study investigated in vitro release of the anticonvulsant ethosuximide from nanocapsule-based N,O-carboxymethyl chitosan and hyaluronan-methylcellulose hydrogels using two experimental designs: a one-factor-at-a-time method and an optimization method employing a Taguchi design. Using the first method, the release rate of the drug was significantly reduced compared with other delivery systems. With the second method, when the drug was blended into a hyaluronan-methylcellulose hydrogel the release rate was similarly reduced, with full release occurring after three days. Scanning electron microscopy, Fourier-transform infrared spectroscopy, and ultraviolet-visible spectrophotometry were used to study the drug encapsulation, and two mathematical models for evaluating encapsulation efficiency were developed. The results of this study show promise for use of nanoencapsulated thermoresponsive hydrogels in clinical delivery of anticonvulsants. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Ferrociphenol lipid nanocapsule delivery by mesenchymal stromal cells in brain tumor therapy.

    PubMed

    Roger, Mathilde; Clavreul, Anne; Huynh, Ngoc Trinh; Passirani, Catherine; Schiller, Paul; Vessières, Anne; Montero-Menei, Claudia; Menei, Philippe

    2012-02-14

    The prognosis of patients with malignant glioma remains extremely poor despite surgery and improvements in radio- and chemo-therapies. Thus, treatment strategies that specifically target these tumors have the potential to greatly improve therapeutic outcomes. "Marrow-isolated adult multilineage inducible" cells (MIAMI cells) are a subpopulation of mesenchymal stromal cells (MSCs) which possess the ability to migrate to brain tumors. We have previously shown that MIAMI cells were able to efficiently incorporate lipid nanocapsules (LNCs) without altering either their stem cell properties or their migration capacity. In this study, we assessed whether the cytotoxic effects of MIAMI cells loaded with LNCs containing an organometallic complex (ferrociphenol or Fc-diOH) could be used to treat brain tumors. The results showed that MIAMI cells internalized Fc-diOH-LNCs and that this internalization did not induce MIAMI cell death. Furthermore, Fc-diOH-LNC-loaded MIAMI cells produced a cytotoxic effect on U87MG glioma cells in vitro. This cytotoxic effect was validated in vivo after intratumoral injection of Fc-diOH-LNC-loaded MIAMI cells in a heterotopic U87MG glioma model in nude mice. These promising results open up a new field of treatment in which cellular vehicles and nanoparticles can be combined to treat brain tumors. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. NFL-lipid nanocapsules for brain neural stem cell targeting in vitro and in vivo.

    PubMed

    Carradori, Dario; Saulnier, Patrick; Préat, Véronique; des Rieux, Anne; Eyer, Joel

    2016-09-28

    The replacement of injured neurons by the selective stimulation of neural stem cells in situ represents a potential therapeutic strategy for the treatment of neurodegenerative diseases. The peptide NFL-TBS.40-63 showed specific interactions towards neural stem cells of the subventricular zone. The aim of our work was to produce a NFL-based drug delivery system able to target neural stem cells through the selective affinity between the peptide and these cells. NFL-TBS.40-63 (NFL) was adsorbed on lipid nanocapsules (LNC) whom targeting efficiency was evaluated on neural stem cells from the subventricular zone (brain) and from the central canal (spinal cord). NFL-LNC were incubated with primary neural stem cells in vitro or injected in vivo in adult rat brain (right lateral ventricle) or spinal cord (T10). NFL-LNC interactions with neural stem cells were different depending on the origin of the cells. NFL-LNC showed a preferential uptake by neural stem cells from the brain, while they did not interact with neural stem cells from the spinal cord. The results obtained in vivo correlate with the results observed in vitro, demonstrating that NFL-LNC represent a promising therapeutic strategy to selectively deliver bioactive molecules to brain neural stem cells. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Inner ear biocompatibility of lipid nanocapsules after round window membrane application.

    PubMed

    Zhang, Ya; Zhang, Weikai; Löbler, Marian; Schmitz, Klaus-Peter; Saulnier, Patrick; Perrier, Thomas; Pyykkö, Ilmari; Zou, Jing

    2011-02-14

    Nanoparticle-mediated drug delivery represents the future in terms of treating inner ear diseases. Lipid core nanocapsules (LNCs), 50 nm in size, were shown to pass though the round window membrane (RWM) and reached the spiral ganglion cells and nerve fibers, among other cell types in the inner ear. The present study aimed to evaluate the toxicity of the LNCs in vitro and in vivo, utilizing intact round window membrane delivery in rats. The primary cochlear cells and mouse fibroblast cells treated with LNCs displayed dosage dependant toxicity. In vivo study showed that administration of LNCs did not cause hearing loss, nanoparticle application-related cell death, or morphological changes in the inner ear, at up to 28 days of observation. The cochlear neural elements, such as synaptophysin, ribbon synapses, and S-100, were not affected by the administration of LNCs. However, expression of neurofilament-200 decreased in SGCs and in cochlear nerve in osseous spiral lamina canal after LNC delivery, a phenomenon that requires further investigation. LNCs are potential vectors for the delivery of drugs to the inner ear. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. Blinking Phase-Change Nanocapsules Enable Background-Free Ultrasound Imaging

    PubMed Central

    Hannah, Alexander S.; Luke, Geoffrey P.; Emelianov, Stanislav Y.

    2016-01-01

    Microbubbles are widely used as contrast agents to improve the diagnostic capability of conventional, highly speckled, low-contrast ultrasound imaging. However, while microbubbles can be used for molecular imaging, these agents are limited to the vascular space due to their large size (> 1 μm). Smaller microbubbles are desired but their ultrasound visualization is limited due to lower echogenicity or higher resonant frequencies. Here we present nanometer scale, phase changing, blinking nanocapsules (BLInCs), which can be repeatedly optically triggered to provide transient contrast and enable background-free ultrasound imaging. In response to irradiation by near-infrared laser pulses, the BLInCs undergo cycles of rapid vaporization followed by recondensation into their native liquid state at body temperature. High frame rate ultrasound imaging measures the dynamic echogenicity changes associated with these controllable, periodic phase transitions. Using a newly developed image processing algorithm, the blinking particles are distinguished from tissue, providing a background-free image of the BLInCs while the underlying B-mode ultrasound image is used as an anatomical reference of the tissue. We demonstrate the function of BLInCs and the associated imaging technique in a tissue-mimicking phantom and in vivo for the identification of the sentinel lymph node. Our studies indicate that BLInCs may become a powerful tool to identify biological targets using a conventional ultrasound imaging system. PMID:27570556

  14. In vivo imaging of DNA lipid nanocapsules after systemic administration in a melanoma mouse model.

    PubMed

    David, Stephanie; Carmoy, Nathalie; Resnier, Pauline; Denis, Caroline; Misery, Laurent; Pitard, Bruno; Benoit, Jean-Pierre; Passirani, Catherine; Montier, Tristan

    2012-02-14

    The biodistribution of intravenously injected DNA lipid nanocapsules (DNA LNCs), encapsulating pHSV-tk, was analysed by in vivo imaging on an orthotopic melanoma mouse model and by a subsequent treatment with ganciclovir (GCV), using the gene-directed enzyme prodrug therapy (GDEPT) approach. Luminescent melanoma cells, implanted subcutaneously in the right flank of the mice, allowed us to follow tumour growth and tumour localisation with in vivo bioluminescence imaging (BLI). In parallel, DNA LNCs or PEG DNA LNCs (DNA LNCs recovered with PEG(2000)) encapsulating a fluorescent probe, DiD, allowed us to follow their biodistribution with in vivo biofluorescence imaging (BFI). The BF-images confirmed a prolonged circulation-time for PEG DNA LNCs as was previously observed on an ectotopic model of glioma; comparison with BL-images evidenced the colocalisation of PEG DNA LNCs and melanoma cells. After these promising results, treatment with PEG DNA LNCs and GCV on a few animals was performed and the treatment efficacy measured by BLI. The first results showed tumour growth reduction tendency and, once optimised, this therapy strategy could become a new option for melanoma treatment. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Lipid Nanocapsules Loaded with Rhenium-188 Reduce Tumor Progression in a Rat Hepatocellular Carcinoma Model

    PubMed Central

    Vanpouille-Box, Claire; Lacoeuille, Franck; Roux, Jérôme; Aubé, Christophe; Garcion, Emmanuel; Lepareur, Nicolas; Oberti, Frédéric; Bouchet, Francis; Noiret, Nicolas; Garin, Etienne; Benoît, Jean-Pierre; Couturier, Olivier; Hindré, François

    2011-01-01

    Background Due to their nanometric scale (50 nm) along with their biomimetic properties, lipid nanocapsules loaded with Rhenium-188 (LNC188Re-SSS) constitute a promising radiopharmaceutical carrier for hepatocellular carcinoma treatment as its size may improve tumor penetration in comparison with microspheres devices. This study was conducted to confirm the feasibility and to assess the efficacy of internal radiation with LNC188Re-SSS in a chemically induced hepatocellular carcinoma rat model. Methodology/Principal Findings Animals were treated with an injection of LNC188Re-SSS (80 MBq or 120 MBq). The treated animals (80 MBq, n = 12; 120 MBq, n = 11) were compared with sham (n = 12), blank LNC (n = 7) and 188Re-perrhenate (n = 4) animals. The evaluation criteria included rat survival, tumor volume assessment, and vascular endothelial growth factor quantification. Following treatment with LNC188Re-SSS (80 MBq) therapeutic efficiency was demonstrated by an increase in the median survival from 54 to 107% compared with control groups with up to 7 long-term survivors in the LNC188Re-SSS group. Decreased vascular endothelial growth factor expression in the treated rats could indicate alterations in the angiogenesis process. Conclusions/Significance Overall, these results demonstrate that internal radiation with LNC188Re-SSS is a promising new strategy for hepatocellular carcinoma treatment. PMID:21408224

  16. Affibody-displaying bio-nanocapsules effective in EGFR, typical biomarker, expressed in various cancer cells.

    PubMed

    Nishimura, Yuya; Ezawa, Ryosuke; Ishii, Jun; Ogino, Chiaki; Kondo, Akihiko

    2017-01-15

    The expression of epidermal growth factor receptor (EGFR) across a wide range of tumor cells has attracted attention for use as a tumor marker in drug delivery systems. Therefore, binding molecules with the ability to target EGFR have been developed. Among them, we focused on affibodies that are binding proteins derived from staphylococcal protein A. By displaying affibody (ZEGFR) binding to EGFR on the surface of a bio-nanocapsule (BNC) derived from a hepatitis B virus (HBV), we developed an altered BNC (ZEGFR-BNC) with a high specificity to EGFR-expressing cells. We considered two different types of ZEGFR (Z955 and Z1907), and found that the Z1907 dimer-displaying BNC ([Z1907]2-BNC) could effectively bind to EGFR-expressing cells and deliver drugs to the cytosol. Since this study showed that [Z1907]2-BNC could target EGFR-expressing cells, we would use this particle as a drug delivery carrier for various cancer cells expressing EGFR. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Demonstration of the interactions between aromatic compound-loaded lipid nanocapsules and Acinetobacter baumannii bacterial membrane.

    PubMed

    Montagu, A; Joly-Guillou, M-L; Guillet, C; Bejaud, J; Rossines, E; Saulnier, P

    2016-06-15

    Acinetobacter baumannii is an important nosocomial pathogen that is resistant to many commonly-used antibiotics. One strategy for treatment is the use of aromatic compounds (carvacrol, cinnamaldehyde) against A. baumannii. The aim of this study was to determine the interactions between bacteria and lipid nanocapsules (LNCs) over time based on the fluorescence of 3,3'-Dioctadecyloxacarbocyanine Perchlorate-LNCs (DiO-LNCs) and the properties of trypan blue to analyse the physicochemical mechanisms occurring at the level of the biological membrane. The results demonstrated the capacity of carvacrol-loaded LNCs to interact with and penetrate the bacterial membrane in comparison with cinnamaldehyde-loaded LNCs and unloaded LNCs. Modifications of carvacrol after substitution of hydroxyl functional groups by fatty acids demonstrated the crucial role of hydroxyl functions in antibacterial activity. Finally, after contact with the efflux pump inhibitor, carbonylcyanide-3-chlorophenyl hydrazine (CCCP), the results indicated the total synergistic antibacterial effect with Car-LNCs, showing that CCCP is associated with the action mechanism of carvacrol, especially at the level of the efflux pump mechanism.

  18. Lipid-core nanocapsules increase the oral efficacy of quercetin in cutaneous leishmaniasis.

    PubMed

    Sousa-Batista, A J; Poletto, F S; Philipon, C I M S; Guterres, S S; Pohlmann, A R; Rossi-Bergmann, B

    2017-06-27

    New oral treatments are needed for all forms of leishmaniasis. Here, the improved oral efficacy of quercetin (Qc) and its penta-acetylated derivative (PQc) was evaluated in cutaneous leishmaniasis after encapsulation in lipid-core nanocapsules (LNCs) of poly(ε-caprolactone). Leishmania amazonensis-infected BALB/c mice were given 51 daily oral doses of free drugs (16 mg kg-1) or LNC-loaded drugs (0·4 mg kg-1). While treatment with free Qc reduced the lesion sizes and parasite loads by 38 and 71%, respectively, LNC-Qc produced 64 and 91% reduction, respectively. The antileishmanial efficacy of PQc was similar but not as potently improved by encapsulation as Qc. None of the treatments increased aspartate aminotransferase, alanine aminotransferase or creatinine serum levels. These findings indicate that when encapsulated in LNC, Qc and, to a lesser extent, PQc can safely produce an enhanced antileishmanial effect even at a 40-fold lower dose, with implications for the development of a new oral drug for cutaneous leishmaniasis.

  19. Percutaneous absorption of benzophenone-3 loaded lipid nanoparticles and polymeric nanocapsules: A comparative study.

    PubMed

    Gilbert, E; Roussel, L; Serre, C; Sandouk, R; Salmon, D; Kirilov, P; Haftek, M; Falson, F; Pirot, F

    2016-05-17

    For the last years, the increase of the number of skin cancer cases led to a growing awareness of the need of skin protection against ultraviolet (UV) radiations. Chemical UV filters are widely used into sunscreen formulations as benzophenone-3 (BP-3), a usually used broad spectrum chemical UV filter that has been shown to exercise undesirable effects after topical application. Innovative sunscreen formulations are thus necessary to provide more safety to users. Lipid carriers seem to be a good alternative to formulate chemical UV filters reducing their skin penetration while maintaining good photo-protective abilities. The aim of this work was to compare percutaneous absorption and cutaneous bioavailability of BP-3 loaded into solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC), nanostructured polymeric lipid carriers (NPLC) and nanocapsules (NC). Particle size, zeta potential and in vitro sun protection factor (SPF) of nanoparticle suspensions were also investigated. Results showed that polymeric lipid carriers, comprising NPLC and NC, significantly reduced BP-3 skin permeation while exhibiting the highest SPF. This study confirms the interesting potential of NPLC and NC to formulate chemical UV filters.

  20. Designing a Poly (N-isopropylacrylamide) Nanocapsule for Magnetic Field-assisted Drug Delivery

    NASA Astrophysics Data System (ADS)

    Denmark, Daniel; Mukherjee, Pritish; Witanachchi, Sarath

    2014-03-01

    The method of synthesis and the characteristics of polymer based nanocapsules as biomedical drug delivery systems are presented. Magnetic iron oxide nanoparticles have been incorporated into these capsules for effective guidance with external magnetic fields to transport therapeutic compounds to various parts of the human body. Once they have reached their destination they can be stimulated to release the drug to the target tissue through externally applied fields. The polymeric material that constitutes the capsules is specifically designed to melt away with the external stimuli to deliver the therapeutic bio agents near the target tissue. In this work we use nebulization to create aqueous poly (N-isopropylacrylamide) nanoparticles that decompose after being heated beyond their transition temperature. Transmission Electron Microscopic imaging (TEM) and dynamic light scattering (DLS) experiments have been conducted to study the decomposition of the capsules under external stimuli. Distribution of the magnetic nanoparticles within the capsules and their role in delivering the bio agents have been investigated by the Magnetic Force Microscopy (MFM).

  1. Distribution of lipid nanocapsules in different cochlear cell populations after round window membrane permeation.

    PubMed

    Zou, Jing; Saulnier, Patrick; Perrier, Thomas; Zhang, Ya; Manninen, Tommi; Toppila, Esko; Pyykkö, Ilmari

    2008-10-01

    Hearing loss is a major public health problem, and its treatment with traditional therapy strategies is often unsuccessful due to limited drug access deep in the temporal bone. Multifunctional nanoparticles that are targeted to specified cell populations, biodegradable, traceable in vivo, and equipped with controlled drug/gene release may resolve this problem. We developed lipid core nanocapsules (LNCs) with sizes below 50 nm. The aim of the present study is to evaluate the ability of the LNCs to pass through the round window membrane and reach inner ear targets. FITC was incorporated as a tag for the LNCs and Nile Red was encapsulated inside the oily core to assess the integrity of the LNCs. The capability of LNCs to pass through the round window membrane and the distribution of the LNCs inside the inner ear were evaluated in rats via confocal microscopy in combination with image analysis using ImageJ. After round window membrane administration, LNCs reached the spiral ganglion cells, nerve fibers, and spiral ligament fibrocytes within 30 min. The paracellular pathway was the main approach for LNC penetration of the round window membrane. LNCs can also reach the vestibule, middle ear mucosa, and the adjacent artery. Nuclear localization was detected in the spiral ganglion, though infrequently. These results suggest that LNCs are potential vectors for drug delivery into the spiral ganglion cells, nerve fibers, hair cells, and spiral ligament.

  2. Immune cell impact of three differently coated lipid nanocapsules: pluronic, chitosan and polyethylene glycol

    PubMed Central

    Farace, Cristiano; Sánchez-Moreno, Paola; Orecchioni, Marco; Manetti, Roberto; Sgarrella, Francesco; Asara, Yolande; Peula-García, José M.; Marchal, Juan A.; Madeddu, Roberto; Delogu, Lucia G.

    2016-01-01

    Lipid nanocapsules (NCs) represent promising tools in clinical practice for diagnosis and therapy applications. However, the NC appropriate functionalization is essential to guarantee high biocompatibility and molecule loading ability. In any medical application, the immune system-impact of differently functionalized NCs still remains to be fully understood. A comprehensive study on the action exerted on human peripheral blood mononuclear cells (PBMCs) and major immune subpopulations by three different NC coatings: pluronic, chitosan and polyethylene glycol-polylactic acid (PEG) is reported. After a deep particle characterization, the uptake was assessed by flow-cytometry and confocal microscopy, focusing then on apoptosis, necrosis and proliferation impact in T cells and monocytes. Cell functionality by cell diameter variations, different activation marker analysis and cytokine assays were performed. We demonstrated that the NCs impact on the immune cell response is strongly correlated to their coating. Pluronic-NCs were able to induce immunomodulation of innate immunity inducing monocyte activations. Immunomodulation was observed in monocytes and T lymphocytes treated with Chitosan-NCs. Conversely, PEG-NCs were completely inert. These findings are of particular value towards a pre-selection of specific NC coatings depending on biomedical purposes for pre-clinical investigations; i.e. the immune-specific action of particular NC coating can be excellent for immunotherapy applications. PMID:26728491

  3. Understanding the adsorption of salmon calcitonin, antimicrobial peptide AP114 and polymyxin B onto lipid nanocapsules.

    PubMed

    Umerska, Anita; Matougui, Nada; Groo, Anne-Claire; Saulnier, Patrick

    2016-06-15

    The adsorption of therapeutic molecules, e.g., peptides, onto nanocarriers is influenced by the properties of the carrier, adsorbed molecule and continuous phase. Hence, through changes in the composition of the nanocarrier and the medium, it should be possible to tune the system to make it capable of efficiently adsorbing peptides. The adsorption of calcitonin, antimicrobial peptide AP114 and polymyxin B onto lipid nanocapsules was investigated. The adsorption data were fitted to a Langmuir isotherm. Dynamic light scattering and laser Doppler velocimetry were used to investigate the changes in the hydrodynamic diameter and zeta potential, respectively, of the nanocarrier. The peptide adsorption was primarily governed by electrostatic forces; however, even without the presence of an ionisable surfactant, a significant amount of each tested molecule was adsorbed due to the enormous surface area of the nanocarriers and to peptide-nanocarrier interactions. The addition of an ionisable lipophilic surfactant, lecithin, improved the adsorption yield, which reached values of up to 100%. The adsorption yield and the properties of the nanocarrier, particularly the zeta potential, depended on the carrier and peptide concentrations and their mixing ratio. The adsorption of all tested molecules obeyed the Langmuir model over a limited concentration range.

  4. Enhancing radiotherapy by lipid nanocapsule-mediated delivery of amphiphilic gold nanoparticles to intracellular membranes.

    PubMed

    Yang, Yu-Sang; Carney, Randy P; Stellacci, Francesco; Irvine, Darrell J

    2014-09-23

    Amphiphilic gold nanoparticles (amph-NPs), composed of gold cores surrounded by an amphiphilic mixed organic ligand shell, are capable of embedding within and traversing lipid membranes. Here we describe a strategy using crosslink-stabilized lipid nanocapsules (NCs) as carriers to transport such membrane-penetrating particles into tumor cells and promote their transfer to intracellular membranes for enhanced radiotherapy of cancer. We synthesized and characterized interbilayer-crosslinked multilamellar lipid vesicles (ICMVs) carrying amph-NPs embedded in the capsule walls, forming Au-NCs. Confocal and electron microscopies revealed that the intracellular distribution of amph-NPs within melanoma and breast tumor cells following uptake of free particles vs Au-NCs was quite distinct and that amph-NPs initially delivered into endosomes by Au-NCs transferred over a period of hours to intracellular membranes through tumor cells, with greater intracellular spread in melanoma cells than breast carcinoma cells. Clonogenic assays revealed that Au-NCs enhanced radiotherapeutic killing of melanoma cells. Thus, multilamellar lipid capsules may serve as an effective carrier to deliver amphiphilic gold nanoparticles to tumors, where the membrane-penetrating properties of these materials can significantly enhance the efficacy of frontline radiotherapy treatments.

  5. Treatment of acute thromboembolism in mice using heparin-conjugated carbon nanocapsules.

    PubMed

    Tang, Alan C L; Chang, Ming-Yao; Tang, Zack C W; Li, Hui-Jing; Hwang, Gan-Lin; Hsieh, Patrick C H

    2012-07-24

    The unsurpassed properties in electrical conductivity, thermal conductivity, strength, and surface area-to-volume ratio allow for many potential applications of carbon nanomaterials in various fields. Recently, studies have characterized the potential of using carbon nanotubes (CNTs) as a biomaterial for biomedical applications and as a drug carrier via intravenous injection. However, most studies show that unmodified CNTs possess a high degree of toxicity and cause inflammation, mechanical obstruction from high organ retention, and other biocompatibility issues following in vivo delivery. In contrast, carbon nanocapsules (CNCs) have a lower aspect ratio compared with CNTs and have a higher dispersion rate. To investigate the possibility of using CNCs as an alternative to CNTs for drug delivery, heparin-conjugated CNCs (CNC-H) were studied in a mouse model of acute hindlimb thromboembolism. Our results showed that CNC-H not only displayed superior antithrombotic activity in vitro and in vivo but they also had the ability to extend the thrombus formation time far longer than an injection of heparin or CNCs alone. Therefore, the present study showed for the first time that functionalized CNCs can act as nanocarriers to deliver thrombolytic therapeutics.

  6. Dodecyl creatine ester and lipid nanocapsule: a double strategy for the treatment of creatine transporter deficiency.

    PubMed

    Trotier-Faurion, Alexandra; Passirani, Catherine; Béjaud, Jérôme; Dézard, Sophie; Valayannopoulos, Vassili; Taran, Fréderic; de Lonlay, Pascale; Benoit, Jean-Pierre; Mabondzo, Aloïse

    2015-01-01

    Creatine transporter (CT) deficiency is characterized by mutations in the gene encoding CT, leading to impaired transport of creatine at the cell membrane. Patients with this disease would thus benefit from replenishment of creatine inside the brain cells. We report a therapeutic strategy based on the use of dodecyl creatine ester incorporated into lipid nanocapsules (LNCs). The dodecyl creatine ester was incorporated in the shells of LNCs using Transcutol(®) (Gattefossé SAS, Saint-Priest, France). The interactions of dodecyl creatine ester encapsulated in LNCs with an in vitro cell-based blood-brain barrier model was studied. The entry of the dodecyl creatine ester encapsulated in LNCs and the conversion of dodecyl creatine ester to creatine in the cells were also studied in the pathological context of CT deficiency. We showed that these LNCs can cross the blood-brain barrier and enter brain endothelial cells. In human fibroblasts lacking functional CT, all or part of the dodecyl creatine ester was released from the LNCs and biotransformed to creatine, thus indicating the value of this strategy in this therapeutic context.

  7. Novel biocompatible nanocapsules for slow release of fragrances on the human skin.

    PubMed

    Hosseinkhani, Baharak; Callewaert, Chris; Vanbeveren, Nelleke; Boon, Nico

    2015-01-25

    There is a growing demand for fragranced products, but due to the poor aqueous solubility and instability of fragrance molecules, their use is limited. Nowadays, fragrance encapsulation in biocompatible nanocontainer material is emerging as a novel strategy to overcome the evaporation of volatile molecules and to prolong the sensory characteristics of fragrance molecules and the longevity of perfumes. The objective of this study was to develop an innovative sustained release system of perfume, by entrapping fragrance molecules in a polymeric nanocarrier; the impact of this strategy on the human axillary microbiome was further assessed. Stabilised poly-l-lactic acid nanocapsules (PLA-NCs) with a diameter of approximately 115 nm were prepared through nanoprecipitation. Size and morphology of the capsules were evaluated using Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS). Two model hydrophobic compounds, chlorobenzene and fluorescein, representing two different types of functionalised molecules, were encapsulated in PLA-NCs with an efficiency rate of 50%. Different release behaviours were seen, dependent on hydrophobicity. For hydrophobic compounds, a steady release was observed over 48hours. The polymeric nanocarriers did not impact the human axillary microbiome. Because of the slow and sustained release of fragrances, encapsulation of molecules in biocompatible NCs can represent a revolutionary contribution to the future of toiletries, body deodorant products, and in washing and cleaning sectors.

  8. Frozen shoulder and the Big Five personality traits.

    PubMed

    Debeer, Philippe; Franssens, Fien; Roosen, Isabelle; Dankaerts, Wim; Claes, Laurence

    2014-02-01

    In the past, several studies have suggested the existence of a "periarthritic personality" in patients with frozen shoulder. We conducted a study to determine differences in personality traits in patients with primary and secondary frozen shoulders. We prospectively evaluated 118 patients (84 women and 34 men; mean age, 53.8 years; SD 7.56) with a frozen shoulder. Of these patients, 48 had an idiopathic frozen shoulder and 70 had a secondary frozen shoulder. Personality traits were determined by the NEO Five-Factor Inventory (NEO-FFI) scale. This questionnaire measures the 5 major personality traits and is based on the norms determined in a neutral test situation for 2415 controls. Compared with healthy controls, no differences in personality traits were found in patients with primary and secondary frozen shoulder, except for Conscientiousness and Extraversion, for which patients with secondary frozen shoulder scored significantly higher than healthy controls. Patients with primary frozen shoulder scored significantly higher on Openness to Experience than did patients with secondary frozen shoulder; on the other 4 Big Five personality traits, no significant differences were found between patients with primary and secondary frozen shoulder. More specifically, patients with idiopathic frozen shoulder did not score higher on the trait Neuroticism as would be expected from previous publications. Our study results do not indicate that patients with an idiopathic frozen shoulder have a specific personality compared with healthy controls. Only a few differences were found in personality traits when the entire frozen shoulder group was compared with healthy controls and between patients with primary and secondary frozen shoulders. The results of this study suggest that these differences are not sufficient to speak about a specific "frozen shoulder personality." Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights

  9. 21 CFR 101.95 - “Fresh,” “freshly frozen,” “fresh frozen,” “frozen fresh.”

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false âFresh,â âfreshly frozen,â âfresh frozen,â âfrozen fresh.â 101.95 Section 101.95 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION FOOD LABELING Specific Requirements...

  10. The Jefferson Lab Frozen Spin Target

    SciTech Connect

    Christopher Keith, James Brock, Christopher Carlin, Sara Comer, David Kashy, Josephine McAndrew, David Meekins, Eugene Pasyuk, Joshua Pierce, Mikell Seely

    2012-08-01

    A frozen spin polarized target, constructed at Jefferson Lab for use inside a large acceptance spectrometer, is described. The target has been utilized for photoproduction measurements with polarized tagged photons of both longitudinal and circular polarization. Protons in TEMPO-doped butanol were dynamically polarized to approximately 90% outside the spectrometer at 5 T and 200-300 mK. Photoproduction data were acquired with the target inside the spectrometer at a frozen-spin temperature of approximately 30 mK with the polarization maintained by a thin, superconducting coil installed inside the target cryostat. A 0.56 T solenoid was used for longitudinal target polarization and a 0.50 T dipole for transverse polarization. Spin relaxation times as high as 4000 hours were observed. We also report polarization results for deuterated propanediol doped with the trityl radical OX063.

  11. [Intraoperative frozen sections of the thyroid gland].

    PubMed

    Synoracki, S; Ting, S; Siebolts, U; Dralle, H; Koperek, O; Schmid, K W

    2015-07-01

    The goal of evaluation of intraoperative frozen sections of the thyroid gland is to achieve a definitive diagnosis which determines the subsequent surgical management as fast as possible; however, due to the specific methodological situation of thyroid frozen sections evaluation a conclusive diagnosis can be made in only some of the cases. If no conclusive histological diagnosis is possible during the operation, subsequent privileged processing of the specimen allows a final diagnosis at the latest within 48 h in almost all remaining cases. Applying this strategy, both pathologists and surgeons require a high level of communication and knowledge regarding the specific diagnostic and therapeutic peculiarities of thyroid malignancies because different surgical strategies must be employed depending on the histological tumor subtype.

  12. The Jefferson Lab frozen spin target

    NASA Astrophysics Data System (ADS)

    Keith, C. D.; Brock, J.; Carlin, C.; Comer, S. A.; Kashy, D.; McAndrew, J.; Meekins, D. G.; Pasyuk, E.; Pierce, J. J.; Seely, M. L.

    2012-08-01

    A frozen spin polarized target, constructed at Jefferson Lab for use inside a large acceptance spectrometer, is described. The target has been utilized for photoproduction measurements with polarized tagged photons of both longitudinal and circular polarization. Protons in TEMPO-doped butanol were dynamically polarized to approximately 90% outside the spectrometer at 5 T and 200-300 mK. Photoproduction data were acquired with the target inside the spectrometer at a frozen-spin temperature of approximately 30 mK with the polarization maintained by a thin, superconducting coil installed inside the target cryostat. A 0.56 T solenoid was used for longitudinal target polarization and a 0.50 T dipole for transverse polarization. Spin-lattice relaxation times as high as 4000 h were observed. We also report polarization results for deuterated propanediol doped with the trityl radical OX063.

  13. Nano-emulsions and nanocapsules by the PIT method: an investigation on the role of the temperature cycling on the emulsion phase inversion.

    PubMed

    Anton, Nicolas; Gayet, Pascal; Benoit, Jean-Pierre; Saulnier, Patrick

    2007-11-01

    This paper focuses on the phenomenological understanding of temperature cycling process, applied to the phase inversion temperature (PIT) method. The role of this particular thermal treatment on emulsions phase inversion, as well as its ability to generate nano-emulsions have been investigated. In order to propose a general study, we have based our investigations on a given formulation of nano-emulsions classically proposed in the literature [Heurtault, B., Saulnier, P., Pech, B., Proust, J. E., Benoit, J.P., 2002. A novel phase inversion-based process for the preparation of lipid nanocarriers. Pharm. Res. 19, 875; Lamprecht, A., Bouligand, Y, Benoit, J.P., 2002. New lipid nanocapsules exhibit sustained release properties for amiodarone. J. Control. Release 84, 59-68], using a polyethoxylated model nonionic surfactant, a polyoxyehtylene-660-12-hydroxy stearate, stabilizing the emulsion composed of caprilic triglycerides (triglycerides medium chains), salt water (and also phospholipidic amphiphiles neutral for the formulation). Characterization of nano-emulsions was performed by dynamic light scattering (DLS) which provides the hydrodynamic diameter, but also the polydispersity index (PDI), as a fundamental criteria to judge the quality of the dispersion. Another aspect of the characterization was done following the emulsion inversion and structure by electrical conductivity through the temperature scan. Overall, the role such a temperature cycling process on the formulation of nano-emulsions appears to be relatively important, and globally enhanced as the surfactant concentration is lowered. Actually, both the hydrodynamic diameter and the PDI decrease as a function of the number and temperature cycles up to stabilize a steady state. Eventually, such a cycling process allows the generation of nano-emulsions in ranges of compositions largely expanded when compared with the classical PIT method. These general and interesting trends emerge from the results, are

  14. Demonstration of an Artificial Frozen Barrier

    DTIC Science & Technology

    2012-11-01

    used for deep excavation, tunneling, and underground construction ( Hass and Schäfers 2006). Frozen barriers can be created us- ing artificial...adjacent are soil, rock, or other solids. These mate- rials usually cause problems when more traditional techniques, such as grouting, are used ( Hass ...H. M. 2007. The periglacial environment. Chichester: J. Wiley. Hass , H., and P. Schäfers. 2006. Application of ground freezing for underground

  15. Cutting Frozen Ground with Disc Saws

    DTIC Science & Technology

    1975-06-01

    a (actor ot 5. taking a depth widtli ratio toi the uncut nbs ol 2. Axle torces on the cutter wheel depend on the design ol the cutting teeth and on...position. If the shoulder of the cutting tool behind the cutting edge is exactly tangential, it will grind against uncut material and...AD-A012 114 CUTTING FROZEN GROUND UITH DISC SAWS Mai colm Mel lor Cold Regions Research and Engineering Laboratory Hanover, New

  16. Frozen soil barriers for hazardous waste confinement

    SciTech Connect

    Dash, J.G.; Leger, R.; Fu, H.Y.

    1997-12-31

    Laboratory and full field measurements have demonstrated the effectiveness of artificial ground freezing for the containment of subsurface hazardous and radioactive wastes. Bench tests and a field demonstration have shown that cryogenic barriers are impenetrable to aqueous and non aqueous liquids. As a result of the successful tests the US Department of Energy has designated frozen ground barriers as one of its top ten remediation technologies.

  17. Drug response in organoids generated from frozen primary tumor tissues

    PubMed Central

    Walsh, Alex J.; Cook, Rebecca S.; Sanders, Melinda E.; Arteaga, Carlos L.; Skala, Melissa C.

    2016-01-01

    Primary tumor organoids grown in three-dimensional culture provide an excellent platform for studying tumor progression, invasion, and drug response. However, organoid generation protocols require fresh tumor tissue, which limits organoid research and clinical use. This study investigates cellular morphology, viability, and drug response of organoids derived from frozen tissues. The results demonstrate that viable organoids can be grown from flash-frozen and thawed tissue and from bulk tissues slowly frozen in DMSO supplemented media. While the freezing process affects the basal metabolic rate of the cells, the optical metabolic imaging index correlates between organoids derived from fresh and frozen tissue and can be used to detect drug response of organoids grown from frozen tissues. The slow, DMSO frozen tissue yielded organoids with more accurate drug response than the flash frozen tissues, and thus bulk tissue should be preserved for subsequent organoid generation by slow freezing in DMSO supplemented media. PMID:26738962

  18. Drug response in organoids generated from frozen primary tumor tissues.

    PubMed

    Walsh, Alex J; Cook, Rebecca S; Sanders, Melinda E; Arteaga, Carlos L; Skala, Melissa C

    2016-01-07

    Primary tumor organoids grown in three-dimensional culture provide an excellent platform for studying tumor progression, invasion, and drug response. However, organoid generation protocols require fresh tumor tissue, which limits organoid research and clinical use. This study investigates cellular morphology, viability, and drug response of organoids derived from frozen tissues. The results demonstrate that viable organoids can be grown from flash-frozen and thawed tissue and from bulk tissues slowly frozen in DMSO supplemented media. While the freezing process affects the basal metabolic rate of the cells, the optical metabolic imaging index correlates between organoids derived from fresh and frozen tissue and can be used to detect drug response of organoids grown from frozen tissues. The slow, DMSO frozen tissue yielded organoids with more accurate drug response than the flash frozen tissues, and thus bulk tissue should be preserved for subsequent organoid generation by slow freezing in DMSO supplemented media.

  19. The new frozen spin target at MAMI

    NASA Astrophysics Data System (ADS)

    Thomas, A.; Borisov, N. S.; Arends, H.-J.; Fedorov, A. N.; Gurevich, G. M.; Kondratiev, R. L.; Korolija, M.; Lazarev, A. B.; Martinez, M.; Meyer, W.; Mironov, S. V.; Neganov, A. B.; Pavlov, V. N.; Ortega, H.; Reicherz, G.; Usov, Yu. A.

    2013-11-01

    The new frozen spin polarized target for experiments at the polarized beam of the real photon facility A2 of the MAMI accelerator is described. The A2-collaboration at the Mainz Microtron MAMI is measuring photon absorption cross section using circularly and linearly polarized photons up to the energy of 1.5 GeV. The photons are produced in the' Bremsstrahlungs' process. In the years 2005/2006 the Crystal Ball detector with its unique capability to cope with multi photon final states was set up in Mainz. Since 2010 the experimental apparatus has been completed by a polarized target. The horizontal dilution refrigerator of the Frozen-Spin Target has been constructed and is operated in close cooperation with the Joint Institute for Nuclear Research in Dubna, Russia. The system offers the opportunity to provide longitudinally and transversely polarized protons and deuteron. In this paper the operation experience of this new Frozen-Spin Target and first results from the runs in 2010 and 2011 are presented.

  20. Nuclear protein extraction from frozen porcine myocardium.

    PubMed

    Kuster, Diederik W D; Merkus, Daphne; Jorna, Huub J J; Dekkers, Dick H W; Duncker, Dirk J; Verhoeven, Adrie J M

    2011-06-01

    Protocols for the extraction of nuclear proteins have been developed for cultured cells and fresh tissue, but sometimes only frozen tissue is available. We have optimized the homogenization procedure and subsequent fractionation protocol for the preparation of nuclear protein extracts from frozen porcine left ventricular (LV) tissue. This method gave a highly reproducible protein yield (6.5±0.7% of total protein; mean±SE, n=9) and a 6-fold enrichment of the nuclear marker protein B23. The nuclear protein extracts were essentially devoid of cytosolic, myofilament, and histone proteins. Compared to nuclear extracts from fresh LV tissue, some loss of nuclear proteins to the cytosolic fraction was observed. Using this method, we studied the distribution of tyrosine phosphorylated signal transducer and activator of transcription 3 (PY-STAT3) in LV tissue of animals treated with the β-agonist dobutamine. Upon treatment, PY-STAT3 increased 30.2±8.5-fold in total homogenates, but only 6.9±2.1-fold (n=4, P=0.03) in nuclear protein extracts. Of all PY-STAT3 formed, only a minor fraction appeared in the nuclear fraction. This simple and reproducible protocol yielded nuclear protein extracts that were highly enriched in nuclear proteins with almost complete removal of cytosolic and myofilament proteins. This nuclear protein extraction protocol is therefore well-suited for nuclear proteome analysis of frozen heart tissue collected in biobanks.

  1. Existence of frozen-in coordinate systems

    NASA Technical Reports Server (NTRS)

    Chertkov, A. D.

    1995-01-01

    The 'frozen-in' coordinate systems were first introduced in the works on 'reconnection' and 'magnetic barrier' theories (see review by M.l.Pudovkin and V.S.Semenov, Space Sci. Rev. 41,1 1985). The idea was to utilize the mathematical apparatus developed for 'general relativity' theory to simplify obtaining solutions to the ideal MHD equations set. Magnetic field (B), plasma velocity (v), and their vector product were used as coordinate vectors. But there exist no stationary solutions of ideal MHD set that satisfies the required boundary conditions at infinity (A.D.Chertkov, Solar Wind Seven Conf.,Pergamon Press,1992,165) having non-zero vector product of v and B where v and B originate from the same sphere. The existence of a solution is the hidden mine of the mentioned theories. The solution is constructed in the coordinate system, which is unknown and indeterminate before obtaining this solution. A substitution of the final solution must be done directly into the initial MHD set in order to check the method. One can demonstrate that 'solutions' of Petschek's problem, obtained by 'frozen-in' coordinate systems, does not satisfy just the 'frozen-in' equation, i.e. induction equation. It stems from the fact that Petschek's 're-connection' model, treated as a boundary problem, is over determined. This problem was incorrectly formulated.

  2. Rapid detection of irradiated frozen hamburgers

    NASA Astrophysics Data System (ADS)

    Delincée, Henry

    2002-03-01

    DNA comet assay can be employed as a rapid and inexpensive screening test to check whether frozen ground beef patties (hamburgers) have been irradiated as a means to increase their safety by eliminating pathogenic bacteria, e.g. E. coli O157:H7. Such a detection procedure will provide an additional check on compliance with existing regulations, e.g. enforcement of labelling and rules in international trade. Frozen ready prepared hamburgers from the market place were `electron irradiated' with doses of 0, 1.3, 2.7, 4.5 and 7.2kGy covering the range of potential commercial irradiation. DNA fragmentation in the hamburgers was made visible within a few hours using the comet assay, and non-irradiated hamburgers could be easily discerned from the irradiated ones. Even after 9 months of frozen storage, irradiated hamburgers could be identified. Since DNA fragmentation may also occur with other food processes (e.g. temperature abuse), positive screening tests shall be confirmed using a validated method to specifically prove an irradiation treatment, e.g. EN 1784 or EN 1785.

  3. Electrical conductivity of single molecular junctions assembled from Co- and Co3C-encapsulating carbon nanocapsules.

    PubMed

    Matsuura, Daisuke; Kizuka, Tokushi

    2014-03-01

    Single molecular junctions (SMJs) were assembled from cobalt (Co)- and Co carbide (Co3C)-encapsulating carbon nanocapsules (CNCs) and two gold electrodes inside a high-resolution transmission electron microscope equipped with a specimen-piezomanipulation system. The structure and electrical transport properties of the SMJs were investigated in situ. The current density depended on the perimeter of the contact area between CNCs and the electrodes, showing that the current flowed not through the encapsulated region but rather along the graphene layers of CNCs. It was demonstrated that the properties of graphene can be applied to nanodevices using CNCs irrespective of the encapsulating materials.

  4. Effect of oil phase transition on freeze/thaw-induced demulsification of water-in-oil emulsions.

    PubMed

    Lin, Chang; He, Gaohong; Dong, Chunxu; Liu, Hongjing; Xiao, Gongkui; Liu, YuanFa

    2008-05-20

    Recently, there has been an increasing interest in the breakage of water-in-oil (W/O) emulsions by the freeze/thaw method. Most of the previous works focused on the phase transition of the water droplet phase. This paper emphasizes the effect of continuous oil phase transition. A series of oils with different freezing points were used as oil phases to produce model emulsions, which were then frozen and thawed. The emulsion whose oil phase froze before the water droplet phase did (OFBW) on cooling was readily demulsified with a dewatering ratio as high as over 80%, but the emulsion whose oil phase did not freeze when the water droplet phase did (NOFBW) was relatively hard to break. The difference in demulsification performance between them resulted from the distinction between their demulsification mechanisms via the analyses of the emulsion stability, emulsion crystallization/melting behaviors, oil phase physical properties, and wettability of the frozen oil phase, etc. For the OFBW emulsion, the first-frozen oil phase was ruptured by the volume expansion of the subsequently frozen droplet phase, and meanwhile, some liquid droplet phase was drawn into the fine gaps/crevices of the frozen oil phase to bridge droplets, which were considered to be essential to the emulsion breakage, whereas for the NOFBW emulsion, the demulsification was attributed to the collision mechanism proposed in our previous work. The findings may provide some criteria for selecting a proper oil phase in the emulsion liquid membrane (ELM) process and then offer an alternative approach to recycle the oil phase for continuous operation. This work may also be useful for emulsion stability against temperature cycling.

  5. [Dynamics of clinical changes and healing of purulent wounds in application of nanocapsules of phosphatidylcholine in complex of treatment of patients, suffering the oral cavity floor phlegmon].

    PubMed

    Avetikov, D S; Kuong, Vu Vyet; Stavytskiy, S O; Lokes, K P; Voloshyna, L I

    2015-03-01

    Substantiation of expediency for nanocapsules of phosphatidylcholine (lipin) application, owing antihypoxant, antioxydant and immunostimulating action in complex of treatment of patients, suffering odontogenic phlegmon of oral cavity floor (OPHOCF), is presented. The preparation application have promoted a trustworthy reduction of exudation of purulent content, as well as more rapid occurrence of granulations and the wound epithelization.

  6. The release kinetics of β-carotene nanocapsules/xanthan gum coating and quality changes in fresh-cut melon (cantaloupe).

    PubMed

    Zambrano-Zaragoza, María L; Quintanar-Guerrero, David; Del Real, Alicia; Piñon-Segundo, Elizabeth; Zambrano-Zaragoza, José F

    2017-02-10

    The main aim of this work was to evaluate the effect of the β-carotene release rate from nanocapsules incorporated into a xanthan gumcoating on the physical and physicochemical properties of fresh-cut melon (var. cantaloupe). Several coatings were studied: xanthan gum alone (XG), xanthan gum combined with nanocapsules (Ncs/XG), xanthan gum combined with nanospheres (Nsp/XG), nanocapsules (Ncs), and nanospheres (Nsp), all of which were compared to untreated fresh-cut melon in order to determine their preservation efficiency. The β-carotene release profiles from the Ncs and Ncs/XG treatments corresponded better to a Higuchi-type behavior (t(1/2)) for matrix systems (R2>0.95). Also observed was a good correlation between the release of β-carotene by the Ncs/XG treatment and the minor changes observed in the whiteness index (≤10%) and firmness (≤2%). These results lead to the conclusion that incorporating β-carotene nanocapsules into a polysaccharide matrix improves the properties of the coatings, thereby increasing storage time to 21days at 4°C.

  7. Liquid formulation containing doxorubicin-loaded lipid-core nanocapsules: Cytotoxicity in human breast cancer cell line and in vitro uptake mechanism.

    PubMed

    Antonow, Michelli B; Asbahr, Ana Carolina C; Raddatz, Paula; Beckenkamp, Aline; Buffon, Andréia; Guterres, Sílvia S; Pohlmann, Adriana R

    2017-07-01

    Cancer is a major public health problem in the world, being breast cancer the most frequent cancer affecting women. Despite advances in detection and treatment, mortality rates remain high. Therefore, new approaches for breast cancer treatments are necessary. In this study, our objective was to develop a liquid formulation containing doxorubicin-loaded lipid-core nanocapsules (DOX-LNC), to evaluate the in vitro antiproliferative activity and to determine the nanocapsules uptake by MCF-7 cells. Lipid-core nanocapsules (LNC), blank formulation, and DOX-LNC, proposed treatment, were prepared by self-assembling using the solvent displacement method. Hydrodynamic mean diameters (z-average) were respectively 191±31nm and 230±23nm presenting narrow size distributions. Drug content was 0.102±0.029mgmL(-1) with an encapsulation efficiency higher than 90%. Formulations were applied to semiconfluent MCF-7 cells. After 24h, LNC showed no cytotoxicity, while DOX-LNC showed an IC50 of 4.49 micromolar. After 72h of incubation, DOX-LNC showed an IC50 of 1.60 micromolar demonstrating a sustained effect. The nanocapsules were internalized by endocytosis mediated by caveolin and by fluid phase endocytosis, which are active transport mechanisms. In conclusion, the liquid formulation containing DOX-LNC showed to be a promising product for the breast cancer treatment opening new avenues for further in vivo studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. A healthy patient with bilateral frozen hips preceding bilateral frozen shoulders: a cautionary tale.

    PubMed

    Miller, Abigail R; Arnot, Dean; Wake, Melissa

    2015-11-12

    Adhesive capsulitis of the shoulder (frozen shoulder) is a common disease characterised by spontaneous onset of pain and restriction of movement, followed by 'thawing', with complete or near-complete resolution. Adhesive capsulitis of the hip has been reported in around a dozen patients. This report describes an otherwise-healthy middle-aged woman with apparent sequential resolving adhesive capsulitis of all four ball-and-socket joints over a 9-year period, initially affecting each hip and then each shoulder sequentially. The likely hip diagnosis became clear only retrospectively with development of the second frozen shoulder, 5 years after the first pain. All joints subsequently resolved within the expected timeframe and the patient remains healthy, other than having mild hypertension. This case illustrates that, when hip precedes shoulder involvement, there is the potential for the frozen hip to receive alternate diagnoses for which invasive open hip surgery could unnecessarily be recommended.

  9. Frying stability of rapeseed Kizakinonatane (Brassica napus) oil in comparison with canola oil.

    PubMed

    Ma, Jin-Kui; Zhang, Han; Tsuchiya, Tomohiro; Akiyama, Yoshinobu; Chen, Jie-Yu

    2015-04-01

    This study was carried out to investigate the frying performance of Kizakinonatane (Brassica napus) oil during deep-fat frying of frozen French fries with/without replenishment. Commercial regular canola oil was used for comparison. The frying oils were used during intermittent frying of frozen French fries at 180, 200, and 220 ℃ for 7 h daily over four consecutive days. The Kizakinonatane oil exhibited lower levels of total polar compounds, carbonyl value, and viscosity as well as comparable color (optical density) values to that of the canola oil. The monounsaturated fatty acid/polyunsaturated fatty acid ratios were lower than that of canola oil, whereas the polyunsaturated fatty acid/saturated fatty acid ratios are higher than that of canola oil after heating. Results showed that fresh Kizakinonatane oil contains higher levels of acid value, viscosity, optical density values, tocopherols, and total phenolics contents than that of canola oil. Replenishment with fresh oil had significant effects on all chemical and physical parameters, except the acid value of the Kizakinonatane oil during frying processes. Based on the results, the Kizakinonatane oil is inherently suitable for preparing deep-fried foods at high temperatures. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  10. Hypericin-loaded lipid nanocapsules for photodynamic cancer therapy in vitro

    NASA Astrophysics Data System (ADS)

    Barras, Alexandre; Boussekey, Luc; Courtade, Emmanuel; Boukherroub, Rabah

    2013-10-01

    Hypericin (Hy), a naturally occurring photosensitizer (PS), is extracted from Hypericum perforatum plants, commonly known as St. John's wort. The discovery of the in vitro and in vivo photodynamic activities of hypericin as a photosensitizer generated great interest, mainly to induce a very potent antitumoral effect. However, this compound belongs to the family of naphthodianthrones which are known to be poorly soluble in physiological solutions and produce non-fluorescent aggregates (A. Wirz et al., Pharmazie, 2002, 57, 543; A. Kubin et al., Pharmazie, 2008, 63, 263). These phenomena can reduce its efficiency as a photosensitizer for the clinical application. In the present contribution, we have prepared, characterized, and studied the photochemical properties of Hy-loaded lipid nanocapsule (LNC) formulations. The amount of singlet oxygen (1O2) generated was measured by the use of p-nitroso-dimethylaniline (RNO) as a selective scavenger under visible light irradiation. Our results showed that Hy-loaded LNCs suppressed aggregation of Hy in aqueous media, increased its apparent solubility, and enhanced the production of singlet oxygen in comparison with free drug. Indeed, encapsulation of Hy in LNCs led to an increase of 1O2 quantum yield to 0.29-0.44, as compared to 0.02 reported for free Hy in water. Additionally, we studied the photodynamic activity of Hy-loaded LNCs on human cervical carcinoma (HeLa) and Human Embryonic Kidney (HEK) cells. The cell viability decreased radically to 10-20% at 1 μM, reflecting Hy-loaded LNC25 phototoxicity.Hypericin (Hy), a naturally occurring photosensitizer (PS), is extracted from Hypericum perforatum plants, commonly known as St. John's wort. The discovery of the in vitro and in vivo photodynamic activities of hypericin as a photosensitizer generated great interest, mainly to induce a very potent antitumoral effect. However, this compound belongs to the family of naphthodianthrones which are known to be poorly soluble in

  11. Stability study and lyophilization of vitamin E-loaded nanocapsules prepared by membrane contactor.

    PubMed

    Khayata, N; Abdelwahed, W; Chehna, M F; Charcosset, C; Fessi, H

    2012-12-15

    In this research, we studied the accelerated stability of vitamin E-loaded nanocapsules (NCs) prepared by the nanoprecipitation method. Vitamin E-loaded NCs were optimized firstly at the laboratory scale and then scaled up using the membrane contactor technique. The optimum conditions of the membrane contactor preparation (pilot scale) produced vitamin E-loaded NCs with an average size of 253 nm, polydispersity index 0.19 and a zeta potential -16 mV. The average size, polydispersity index and zeta potential values were 185 nm, 0.12 and -15 mV, respectively for the NCs prepared at laboratory scale. No significant changes were noticed in these values after 3 and 6 months of storage at high temperature (40±2 °C) and relative humidity (75±5%) in spite of vitamin E sensitivity to light, heat and oxygen. The entrapment efficiency of NCs prepared at pilot scale was 97% at the beginning of the stability study, and became (95%, 59%) after 3 and 6 months of storage, respectively. These values at lab-scale were (98%, 96%, and 89%) at time zero and after 3 and 6 months of storage, respectively. This confirms the ability of vitamin E encapsulation to preserve its stability, which is one major goal of our work. Lyophilization of the optimized formula at lab-scale was also performed. Four types of cryoprotectants were tested (poly(vinyl pyrrolidone), sucrose, mannitol, and glucose). Freeze-dried NCs prepared with sucrose were found acceptable. The other lyophilized NCs obtained at different conditions presented large aggregates. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Encapsulation of docetaxel in oily core polyester nanocapsules intended for breast cancer therapy

    NASA Astrophysics Data System (ADS)

    Youm, Ibrahima; Yang, Xiao Yan; Murowchick, James B.; Youan, Bi-Botti C.

    2011-12-01

    This study is designed to test the hypothesis that docetaxel [Doc] containing oily core nanocapsules [NCs] could be successfully prepared with a high percentage encapsulation efficiency [EE%] and high drug loading. The oily core NCs were generated according to the emulsion solvent diffusion method using neutral Labrafac CC and poly( d, l-lactide) [PLA] as oily core and shell, respectively. The engineered NCs were characterized for particle mean diameter, zeta potential, EE%, drug release kinetics, morphology, crystallinity, and cytotoxicity on the SUM 225 breast cancer cell line by dynamic light scattering, high performance liquid chromatography, electron microscopies, powder X-ray diffraction, and lactate dehydrogenase bioassay. Typically, the formation of Doc-loaded, oily core, polyester-based NCs was evidenced by spherical nanometric particles (115 to 582 nm) with a low polydispersity index (< 0.05), high EE% (65% to 93%), high drug loading (up to 68.3%), and a smooth surface. Powder X-ray diffraction analysis revealed that Doc was not present in a crystalline state because it was dissolved within the NCs' oily core and the PLA shell. The drug/polymer interaction has been indeed thermodynamically explained using the Flory-Huggins interaction parameters. Doc release kinetic data over 144 h fitted very well with the Higuchi model ( R 2 > 0.93), indicating that drug release occurred mainly by controlled diffusion. At the highest drug concentration (5 μM), the Doc-loaded oily core NCs (as a reservoir nanosystem) enhanced the native drug cytotoxicity. These data suggest that the oily core NCs are promising templates for controlled delivery of poorly water soluble chemotherapeutic agents, such as Doc.

  13. Miltefosine Lipid Nanocapsules for Single Dose Oral Treatment of Schistosomiasis Mansoni: A Preclinical Study

    PubMed Central

    Eissa, Maha M.; El-Moslemany, Riham M.; Ramadan, Alyaa A.; Amer, Eglal I.; El-Azzouni, Mervat Z.; El-Khordagui, Labiba K.

    2015-01-01

    Miltefosine (MFS) is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD). This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs) as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%), good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs, allowing targeting

  14. Hypericin-loaded lipid nanocapsules for photodynamic cancer therapy in vitro.

    PubMed

    Barras, Alexandre; Boussekey, Luc; Courtade, Emmanuel; Boukherroub, Rabah

    2013-11-07

    Hypericin (Hy), a naturally occurring photosensitizer (PS), is extracted from Hypericum perforatum plants, commonly known as St. John's wort. The discovery of the in vitro and in vivo photodynamic activities of hypericin as a photosensitizer generated great interest, mainly to induce a very potent antitumoral effect. However, this compound belongs to the family of naphthodianthrones which are known to be poorly soluble in physiological solutions and produce non-fluorescent aggregates (A. Wirz et al., Pharmazie, 2002, 57, 543; A. Kubin et al., Pharmazie, 2008, 63, 263). These phenomena can reduce its efficiency as a photosensitizer for the clinical application. In the present contribution, we have prepared, characterized, and studied the photochemical properties of Hy-loaded lipid nanocapsule (LNC) formulations. The amount of singlet oxygen ((1)O2) generated was measured by the use of p-nitroso-dimethylaniline (RNO) as a selective scavenger under visible light irradiation. Our results showed that Hy-loaded LNCs suppressed aggregation of Hy in aqueous media, increased its apparent solubility, and enhanced the production of singlet oxygen in comparison with free drug. Indeed, encapsulation of Hy in LNCs led to an increase of (1)O2 quantum yield to 0.29-0.44, as compared to 0.02 reported for free Hy in water. Additionally, we studied the photodynamic activity of Hy-loaded LNCs on human cervical carcinoma (HeLa) and Human Embryonic Kidney (HEK) cells. The cell viability decreased radically to 10-20% at 1 μM, reflecting Hy-loaded LNC25 phototoxicity.

  15. Vesicles from pH-regulated reversible gemini amino-acid surfactants as nanocapsules for delivery.

    PubMed

    Lv, Jing; Qiao, Weihong; Li, Zongshi

    2016-10-01

    Reversible transition from micelles to vesicles by regulating pH were realized by gemini amino-acid surfactants N,N'-dialkyl-N,N'-diacetate ethylenediamine. Measurement results of ζ-potential at different pH and DLS at varying solvents revealed that the protonation between H(+) and double NCH2COO(-) groups (generating NH(+)CH2COO(-)), expressed as pKa1 and pKa2, is the key driving force to control the aggregation behaviors of gemini surfactant molecule. Effect of pH on the bilayer structure was studied in detail by using steady-state fluorescence spectroscopy of hydrophobic pyrene and Coumarin 153 (C153) respectively and fluorescence resonance energy transfer (FRET) from C153 to Rhodamine 6G (R6G). Various pH-regulated and pH-reversible self-assemblies were obtained in one surfactant system. Vitamin D3 was encapsulated in vesicle bilayers to form nano-VD3-capsules as VD3 supplement agent for health care products. By using the electrostatic attraction between Ca(2+) and double -COO(-) groups, nano-VD3-capsules with Ca(2+) coated outermost layers were prepared as a formulation for VD3 and calcium co-supplement agent. DLS and TEM were performed to check stability and morphology of the nano-capsules. It is concluded that the pH-regulated gemini amino-acid surfactants can be used to construct colloidal systems for delivering hydrophobic drugs or nutritions without lipids at human physiological pH level. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Oral administration of encapsulated bovine lactoferrin protein nanocapsules against intracellular parasite Toxoplasma gondii.

    PubMed

    Anand, Namrata; Sehgal, Rakesh; Kanwar, Rupinder Kaur; Dubey, Mohan Lal; Vasishta, Rakesh Kumar; Kanwar, Jagat Rakesh

    2015-01-01

    Toxoplasma gondii is a deadly intracellular parasite known to reside in every nucleated cell and known to cause severe complications in immunocompromised host. Standard drugs are cost effective and cause side effects, therefore, there is a necessity for a new drug molecule with immunomodulatory potential. Lactoferrin (Lf) is a natural milk protein, which has shown antimicrobial properties in its nanoformulation using alginate chitosan calcium phosphate bovine lactoferrin nanocapsules (AEC-CCo-CP-bLf-NCs). The present study was aimed to analyze and compare the effect of bovine Lf (bLf) in its native as well as nanoformulation (AEC-CCo-CP-bLf-NC) against coccidian parasite T. gondii. In vitro analysis has shown a significant increase in nitric oxide production and low parasitemia in in vitro cell culture model. In vivo BALB/c mice model have been used to develop human toxoplasmosis model. After treatment with NCs it has substantially increased the bioavailability of the protein and showed comparatively increased levels of reactive oxygen species, nitric oxide production, and Th1 cytokine which helped in parasite clearance. The mechanism of action of NCs has been clarified by immunoreactivity analysis, which showed accumulation of Lf in macrophages of various visceral organs, which is the site of parasite multiplication. Effect of NCs has significantly decreased (P<0.05) the parasite load in various organs and helped survival of mice till day 25 postinfection. Fe metabolism inside the mice has been found to be maintained even after administration of mono form of Lf, this indicates novelty of Lf protein. From the present study we concluded that nanoformulation did not reduce the therapeutic potential of Lf protein; however, nanoformulation has enhanced the stability of the protein and shown anti-toxoplasmal activity. Our study presents for the first time nanoformulation of Lf protein against Toxoplasma, which has advantages over the standard drug therapy without any

  17. Guests inducing p-sulfonatocalix[4]arenes into nanocapsule and layer structure

    SciTech Connect

    Zheng Guoli; Fan Weiqiang; Song Shuyan; Guo Huadong; Zhang Hongjie

    2010-06-15

    Reaction of sodium p-sulfonatocalix[4]arene and TbCl{sub 3} in the presence of 2,2'-bipyridine-N,N'-dioxide (bpdo) gives the 2:1 supramolecular nanocapsule [[Tb(bpdo){sub 2}.4H{sub 2}O]{sup 3+} intersection {l_brace}p-sulfonatocalix[4]arene{sup 4-{r_brace}}{sub 2}], which further interacts with the [Tb(bpdo){sub 4}]{sup 3+} through charge-assisted {pi}-stacking interactions forming a channel structure 1. In further investigation, we tried to use the terpyridine-1,1',1'-trisoxide (tpto) instead of bpdo. Although we failed to isolate a supramolecular capsules based on the tpto, lanthanide and p-sulfonatocalix[4]arene, a layer structure derived from p-sulfonatocalix[4]arene with an unusual [Cu(tpto){sub 2}]{sup 2+} incorporation into the cavity of the calixarene and an outside [Cu(tpto){sub 2}]{sup 2+} balancing the charge, has been obtained. Fluorescence spectra show clearly that compound 1 possesses the luminescence characteristics of Tb{sup 3+} and the ligand bpdo can sensitize Tb{sup 3+} ion. Gas sorption experiment shows the channel structure 1 has highly selective gas sorption properties for water and methanol. - Graphical abstract: In the presence of different guests, a nanochannel architecture based on the p-sulfonato[4]calixarene capsule and a layered structure based on the p-sulfonato[4]calixarene tecton have been synthesized, and the luminescence properties and guest sorption of porous structure have been investigated.

  18. Elucidation of the early infection machinery of hepatitis B virus by using bio-nanocapsule

    PubMed Central

    Liu, Qiushi; Somiya, Masaharu; Kuroda, Shun’ichi

    2016-01-01

    Currently, hepatitis B virus (HBV), upon attaching to human hepatocytes, is considered to interact first with heparan sulfate proteoglycan (HSPG) via an antigenic loop of HBV envelope S protein. Then, it is promptly transferred to the sodium taurocholate cotransporting polypeptide (NTCP) via the myristoylated N-terminal sequence of pre-S1 region (from Gly-2 to Gly-48, HBV genotype D), and it finally enters the cell by endocytosis. However, it is not clear how HSPG passes HBV to NTCP and how NTCP contributes to the cellular entry of HBV. Owing to the poor availability and the difficulty of manipulations, including fluorophore encapsulation, it has been nearly impossible to perform biochemical and cytochemical analyses using a substantial amount of HBV. A bio-nanocapsule (BNC), which is a hollow nanoparticle consisting of HBV envelope L protein, was efficiently synthesized in Saccharomyces cerevisiae. Since BNC could encapsulate payloads (drugs, genes, proteins) and specifically enter human hepatic cells utilizing HBV-derived infection machinery, it could be used as a model of HBV infection to elucidate the early infection machinery. Recently, it was demonstrated that the N-terminal sequence of pre-S1 region (from Asn-9 to Gly-24) possesses low pH-dependent fusogenic activity, which might play a crucial role in the endosomal escape of BNC payloads and in the uncoating process of HBV. In this minireview, we describe a model in which each domain of the HBV L protein contributes to attachment onto human hepatic cells through HSPG, initiation of endocytosis, interaction with NTCP in endosomes, and consequent provocation of membrane fusion followed by endosomal escape. PMID:27784961

  19. Miltefosine Lipid Nanocapsules for Single Dose Oral Treatment of Schistosomiasis Mansoni: A Preclinical Study.

    PubMed

    Eissa, Maha M; El-Moslemany, Riham M; Ramadan, Alyaa A; Amer, Eglal I; El-Azzouni, Mervat Z; El-Khordagui, Labiba K

    2015-01-01

    Miltefosine (MFS) is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD). This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs) as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%), good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs, allowing targeting

  20. Encapsulation of docetaxel in oily core polyester nanocapsules intended for breast cancer therapy

    PubMed Central

    2011-01-01

    This study is designed to test the hypothesis that docetaxel [Doc] containing oily core nanocapsules [NCs] could be successfully prepared with a high percentage encapsulation efficiency [EE%] and high drug loading. The oily core NCs were generated according to the emulsion solvent diffusion method using neutral Labrafac CC and poly(d, l-lactide) [PLA] as oily core and shell, respectively. The engineered NCs were characterized for particle mean diameter, zeta potential, EE%, drug release kinetics, morphology, crystallinity, and cytotoxicity on the SUM 225 breast cancer cell line by dynamic light scattering, high performance liquid chromatography, electron microscopies, powder X-ray diffraction, and lactate dehydrogenase bioassay. Typically, the formation of Doc-loaded, oily core, polyester-based NCs was evidenced by spherical nanometric particles (115 to 582 nm) with a low polydispersity index (< 0.05), high EE% (65% to 93%), high drug loading (up to 68.3%), and a smooth surface. Powder X-ray diffraction analysis revealed that Doc was not present in a crystalline state because it was dissolved within the NCs' oily core and the PLA shell. The drug/polymer interaction has been indeed thermodynamically explained using the Flory-Huggins interaction parameters. Doc release kinetic data over 144 h fitted very well with the Higuchi model (R2 > 0.93), indicating that drug release occurred mainly by controlled diffusion. At the highest drug concentration (5 μM), the Doc-loaded oily core NCs (as a reservoir nanosystem) enhanced the native drug cytotoxicity. These data suggest that the oily core NCs are promising templates for controlled delivery of poorly water soluble chemotherapeutic agents, such as Doc. PMID:22168815

  1. Oral administration of encapsulated bovine lactoferrin protein nanocapsules against intracellular parasite Toxoplasma gondii

    PubMed Central

    Anand, Namrata; Sehgal, Rakesh; Kanwar, Rupinder Kaur; Dubey, Mohan Lal; Vasishta, Rakesh Kumar; Kanwar, Jagat Rakesh

    2015-01-01

    Toxoplasma gondii is a deadly intracellular parasite known to reside in every nucleated cell and known to cause severe complications in immunocompromised host. Standard drugs are cost effective and cause side effects, therefore, there is a necessity for a new drug molecule with immunomodulatory potential. Lactoferrin (Lf) is a natural milk protein, which has shown antimicrobial properties in its nanoformulation using alginate chitosan calcium phosphate bovine lactoferrin nanocapsules (AEC-CCo-CP-bLf-NCs). The present study was aimed to analyze and compare the effect of bovine Lf (bLf) in its native as well as nanoformulation (AEC-CCo-CP-bLf-NC) against coccidian parasite T. gondii. In vitro analysis has shown a significant increase in nitric oxide production and low parasitemia in in vitro cell culture model. In vivo BALB/c mice model have been used to develop human toxoplasmosis model. After treatment with NCs it has substantially increased the bioavailability of the protein and showed comparatively increased levels of reactive oxygen species, nitric oxide production, and Th1 cytokine which helped in parasite clearance. The mechanism of action of NCs has been clarified by immunoreactivity analysis, which showed accumulation of Lf in macrophages of various visceral organs, which is the site of parasite multiplication. Effect of NCs has significantly decreased (P<0.05) the parasite load in various organs and helped survival of mice till day 25 postinfection. Fe metabolism inside the mice has been found to be maintained even after administration of mono form of Lf, this indicates novelty of Lf protein. From the present study we concluded that nanoformulation did not reduce the therapeutic potential of Lf protein; however, nanoformulation has enhanced the stability of the protein and shown anti-toxoplasmal activity. Our study presents for the first time nanoformulation of Lf protein against Toxoplasma, which has advantages over the standard drug therapy without any

  2. Characterisation and Skin Distribution of Lecithin-Based Coenzyme Q10-Loaded Lipid Nanocapsules

    NASA Astrophysics Data System (ADS)

    Zhou, Huafeng; Yue, Yang; Liu, Guanlan; Li, Yan; Zhang, Jing; Yan, Zemin; Duan, Mingxing

    2010-10-01

    The purpose of this study was to investigate the influence of the inner lipid ratio on the physicochemical properties and skin targeting of surfactant-free lecithin-based coenzyme Q10-loaded lipid nanocapsules (CoQ10-LNCs). The smaller particle size of CoQ10-LNCs was achieved by high pressure and a lower ratio of CoQ10/GTCC (Caprylic/capric triglyceride); however, the zeta potential of CoQ10-LNCs was above /- 60 mV/ with no distinct difference among them at different ratios of CoQ10/GTCC. Both the crystallisation point and the index decreased with the decreasing ratio of CoQ10/GTCC and smaller particle size; interestingly, the supercooled state of CoQ10-LNCs was observed at particle size below about 200 nm, as verified by differential scanning calorimetry (DSC) in one heating-cooling cycle. The lecithin monolayer sphere structure of CoQ10-LNCs was investigated by cryogenic transmission electron microscopy (Cryo-TEM). The skin penetration results revealed that the distribution of Nile red-loaded CoQ10-LNCs depended on the ratio of inner CoQ10/GTCC; moreover, epidermal targeting and superficial dermal targeting were achieved by the CoQ10-LNCs application. The highest fluorescence response was observed at a ratio of inner CoQ10/GTCC of 1:1. These observations suggest that lecithin-based LNCs could be used as a promising topical delivery vehicle for lipophilic compounds.

  3. Oral delivery system prolongs blood circulation of docetaxel nanocapsules via lymphatic absorption.

    PubMed

    Attili-Qadri, Suha; Karra, Nour; Nemirovski, Alina; Schwob, Ouri; Talmon, Yeshayahu; Nassar, Taher; Benita, Simon

    2013-10-22

    An original oral formulation of docetaxel nanocapsules (NCs) embedded in microparticles elicited in rats a higher bioavailability compared with the i.v. administration of the commercial docetaxel solution, Taxotere. In the present study, various animal studies were designed to elucidate the absorption process of docetaxel from such a delivery system. Again, the docetaxel NC formulation elicited a marked enhanced absorption compared with oral Taxotere in minipigs, resulting in relative bioavailability and Cmax values 10- and 8.4-fold higher, respectively, confirming the previous rat study results. It was revealed that orally absorbed NCs altered the elimination and distribution of docetaxel, as shown in the organ biodistribution rat study, due to their reinforced coating, while transiting through the enterocytes by surface adsorption of apoproteins and phospholipids. These findings were demonstrated by the cryogenic-temperature transmission electron microscopy results and confirmed by the use of a chylomicron flow blocker, cycloheximide, that prevented the oral absorption of docetaxel from the NC formulation in an independent pharmacokinetic study. The lipoproteinated NCs reduced the docetaxel release in plasma and its distribution among the organs. The improved anticancer activity compared with i.v. Taxotere, observed in the metastatic lung cancer model in Severe Combined Immune Deficiency-beige (SCID-bg) mice, should be attributed to the extravasation effect, leading to the lipoproteinated NC accumulation in lung tumors, where they exert a significant therapeutic action. To the best of our knowledge, no study has reported that the absorption of NCs was mediated by a lymphatic process and reinforced during their transit.

  4. Resveratrol-loaded lipid-core nanocapsules treatment reduces in vitro and in vivo glioma growth.

    PubMed

    Figueiró, Fabrício; Bernardi, Andressa; Frozza, Rudimar L; Terroso, Thatiana; Zanotto-Filho, Alfeu; Jandrey, Elisa H F; Moreira, José Claudio F; Salbego, Christianne G; Edelweiss, Maria I; Pohlmann, Adriana R; Guterres, Sílvia S; Battastini, Ana Maria O

    2013-03-01

    The development of novel therapeutic strategies to treat gliomas remains critical as a result of the poor prognoses, inef-. ficient therapies and recurrence associated with these tumors. In this context, biodegradable nanoparticles are emerging as efficient drug delivery systems for the treatment of difficult-to-treat diseases such as brain tumors. In the current study, we evaluated the antiglioma effect of trans-resveratrol-loaded lipid-core nanocapsules (RSV-LNC) based on in vitro (C6 glioma cell line) and in vivo (brain-implanted C6 cells) models of the disease. In vitro, RSV-LNC decreased the viability of C6 glioma cells to a higher extent than resveratrol in solution. Interestingly, RSV-LNC treatment was not cytotoxic to hippocampal organotypic cultures, a model of healthy neural cells, suggesting selectivity for cancer cells. RSV-LNC induced losses in glioma cell viability through induction of apoptotic cell death, as assessed by Annexin-FITC/PI assay, which was preceded by an early arrest in the S and G1 phases of the cell cycle. In brain-implanted C6 tumors, treatment with RSV-LNC (5 mg/kg/day, i.p.) for 10 days promoted a marked decrease in tumor size and also reduced the incidence of some malignant tumor-associated characteristics, such as intratumoral hemorrhaging, intratumoral edema and pseudopalisading, compared to resveratrol in solution. Taken together, the results presented herein suggest that nanoencapsulation of resveratrol improves its antiglioma activity, thus providing a provocative foundation for testing the clinical usefulness of nanoformulations of this natural compound as a new chemotherapeutic strategy for the treatment of gliomas.

  5. Gold Nanoshelled Liquid Perfluorocarbon Magnetic Nanocapsules: a Nanotheranostic Platform for Bimodal Ultrasound/Magnetic Resonance Imaging Guided Photothermal Tumor Ablation

    PubMed Central

    Ke, Hengte; Wang, Jinrui; Tong, Sheng; Jin, Yushen; Wang, Shumin; Qu, Enze; Bao, Gang; Dai, Zhifei

    2014-01-01

    Imaging guided ablation therapy has been applied in both biomedical research and clinical trials and turned out to be one of the most promising approaches for cancer treatment. Herein, the multifunctional nanocapsules were fabricated through loading perfluorooctylbromide (PFOB) and superparamagnetic iron oxide nanoparticles (SPIOs) into poly(lactic acid) (PLA) nanocapsules (NCs), followed by the formation of PEGylated gold nanoshell on the surface. The resulting multi-component NCs were proved to be able to act as nanotheranostic agent to achieve successful bimodal ultrasound (US)/magnetic resonance imaging (MRI) guided photothermal ablation in human tumor xenograft models non-invasively. Such a single theranostic agent with the combination of real-time US and high-resolution MR imaging would be of great value to offer more comprehensive diagnostic information and dynamics of disease progression for the accurate location of therapeutic focusing spot in the targeted tumor tissue, showing great potential as an effective nanoplatform for contrast imaging guided photothermal therapy. PMID:24396512

  6. Cationic Polymeric Nanocapsules as a Strategy to Target Dexamethasone to Viable Epidermis: Skin Penetration and Permeation Studies.

    PubMed

    Beber, Tiago Costa; de Andrade, Diego Fontana; Chaves, Paula dos Santos; Pohlmann, Adriana Raffin; Guterres, Silvia Stanisquaski; Beck, Ruy Carlos Ruver

    2016-02-01

    The present work aimed to evaluate the behavior of dexamethasone-loaded cationic polymericnanocapsules in hydrogels, regarding their in vitro drug release and skin drug retention and per- meation. Cationic polymeric nanocapsules prepared with Eudragit RS 100 as the polymeric wall had mean particle size of 139 +/- 3.6 nm, positive zeta potential (+11.38 +/- 1.7 mV), and high encapsulation efficiency (81 +/- 2%). After preparation, they were formulated as hydrogels, which showed non-Newtonian, plastic behavior, and acidic pH. Photon correlation spectroscopy analysis of these hydrogels demonstrated the presence of particles with mean particle size close to that of the original colloidal suspensions. The presence of dexamethasone-loaded nanocapsules in hydrogels promoted controlled drug release and an increase in the amount of drug delivered into viable epidermis, the main target tissue to topical glucocorticoid action. Moreover, the formulation did not increase the risk of drug penetration to dermis and permeation to the receptor compartment.

  7. Stimuli-responsive biodegradable poly(methacrylic acid) based nanocapsules for ultrasound traced and triggered drug delivery system.

    PubMed

    Yang, Peng; Li, Dian; Jin, Sha; Ding, Jing; Guo, Jia; Shi, Weibin; Wang, Changchun

    2014-02-01

    Ultrasound contrast agents (UCAs) have been investigated for echogenic intravenous drug delivery system. Due to the traditional UCAs with overlarge size (micro-scale), their reluctant accumulation in target organs and the instability have presented severe obstacles to the accurate response to the ultrasound and severely limited their further clinical application. Furthermore, elimination of drug carriers from the biologic system after their carrying out the diagnostic or therapeutic functions is one important aspect to be considered. The drug carriers with large sizes, avoiding renal filtration, will lead to increasing toxicity. In this present paper, we design and develop a new type of triple-stimuli responsive (ultrasound/pH/GSH) biodegradable nanocapsules, in which fill up with perfluorohexane, and the DOX-loaded PMAA with disulfide crosslinking forms the wall. These soft nanocapsules with uniform size of 300 nm can easily enter the tumor tissues via EPR effects. The PMAA shell has high DOX-loading content (36 wt%) and great drug loading efficiency (93.5%), the PFH filled can effectively enhance US imaging signal through acoustic droplet vaporization (ADV), ensuring diagnostic and image-guided therapeutic applications. What is more, the disulfide-crosslinked PMAA shell is biodegradable and thus safe for normal organisms. These merits enabled us optimize the balance of diagnostic, therapeutic and biodegradable functionalities in a multifunctional theranostic nanoplatform.

  8. Nanocapsule-delivered Sleeping Beauty mediates therapeutic Factor VIII expression in liver sinusoidal endothelial cells of hemophilia A mice.

    PubMed

    Kren, Betsy T; Unger, Gretchen M; Sjeklocha, Lucas; Trossen, Alycia A; Korman, Vicci; Diethelm-Okita, Brenda M; Reding, Mark T; Steer, Clifford J

    2009-07-01

    Liver sinusoidal endothelial cells are a major endogenous source of Factor VIII (FVIII), lack of which causes the human congenital bleeding disorder hemophilia A. Despite extensive efforts, gene therapy using viral vectors has shown little success in clinical hemophilia trials. Here we achieved cell type-specific gene targeting using hyaluronan- and asialoorosomucoid-coated nanocapsules, generated using dispersion atomization, to direct genes to liver sinusoidal endothelial cells and hepatocytes, respectively. To highlight the therapeutic potential of this approach, we encapsulated Sleeping Beauty transposon expressing the B domain-deleted canine FVIII in cis with Sleeping Beauty transposase in hyaluronan nanocapsules and injected them intravenously into hemophilia A mice. The treated mice exhibited activated partial thromboplastin times that were comparable to those of wild-type mice at 5 and 50 weeks and substantially shorter than those of untreated controls at the same time points. Further, plasma FVIII activity in the treated hemophilia A mice was nearly identical to that in wild-type mice through 50 weeks, while untreated hemophilia A mice exhibited no detectable FVIII activity. Thus, Sleeping Beauty transposon targeted to liver sinusoidal endothelial cells provided long-term expression of FVIII, without apparent antibody formation, and improved the phenotype of hemophilia A mice.

  9. Self-stability of C60 nanocapsules with radio-iodide content and its interaction with calcium atoms.

    PubMed

    Valderrama, Alejandro; Reynoso, Radamés; Gómez, Raúl W; Marquina, Vivianne

    2016-01-01

    This paper inquires the C60 capabilities to contain radio-iodide ((131)I2) molecules. The encapsulation conditions are investigated applying first principles method to simulate with geometric optimizations and molecular dynamics at 310 K and atmospheric pressure. We find that the n(131)I2@C60 system, where n = 1, 2, 3…, is stable if the content does not exceed three molecules of radio-iodide. The application of density functional theory allows us to determine that, the nanocapsules content limit is related with the amount of charge that is transferred from the iodine (131)I2 molecules to the carbon atoms in the fullerene surface. The Mulliken population analysis reveals that the excess of charge increases the repulsive forces between atoms and the bond length average in the C60 structure. The weakened bonds easily break and will critically damage the encapsulation properties. Additionally, we test the interaction nanocapsules with different amounts of radioactive iodine diatomic molecules content with calcium atoms, and find that only the fullerene containing one radioactive iodine diatomic molecule was able to interact with up to nine atoms of calcium without disrupting or cracking. Other fullerenes with two and three radio iodine diatomic molecules cannot resist the interaction with a single calcium atom without cracking or being broken.

  10. Effect of polyethylene glycol coatings on uptake of indocyanine green loaded nanocapsules by human spleen macrophages in vitro

    NASA Astrophysics Data System (ADS)

    Bahmani, Baharak; Gupta, Sharad; Upadhyayula, Srigokul; Vullev, Valentine I.; Anvari, Bahman

    2011-05-01

    Near-infrared (NIR) optically active nanoparticles are promising exogenous chromophores for applications in medical imaging and phototherapy. Since nanoparticles can be rapidly eliminated from the body by cells of the reticuloendothelial system, a thriving strategy to increase their blood circulation time is through surface modification with polyethylene glycol (PEG). We constructed polymeric nanocapsules loaded with indocyanine green (ICG), an FDA-approved NIR dye, and coated with aldehyde-terminated PEG. Using optical absorbance spectroscopy and flow cytometry, we investigated the effect of PEG coating and molecular weight (MW) of PEG [5000 and 30,000 Daltons (Da)] on the phagocytic content of human spleen macrophages incubated with ICG-containing nanocapsules (ICG-NCs) between 15 to 360 min. Our results indicate that surface coating with PEG is an effective method to reduce the phagocytic content of ICG-NCs within macrophages for at least up to 360 min of incubation time. Coating the surface of ICG-NCs with the low MW PEG results in lower phagocytic content of ICG-NCs within macrophages for at least up to 60 min of incubation time as compared to ICG-NCs coated with the high MW PEG. Surface coating of ICG-NCs with PEG is a promising approach to prolong vasculature circulation time of ICG for NIR imaging and phototherapeutic applications.

  11. Photosensitive nanocapsules for use in imaging from poly(styrene-co-divinylbenzene) cross-linked with coumarin derivatives.

    PubMed

    Sierant, Malgorzata; Paluch, Piotr; Florczak, Marcin; Rozanski, Artur; Miksa, Beata

    2013-11-01

    The study objective was to generate biocompatible probes and develop a stable macromolecule imaging system that are based on nanolipopolymersomes and can be used in living cells. We synthesized nanolipopolymersomes with a fluorescent polymer wall surrounded by an outer phospholipid shell that exhibits potential for the controlled delivery of diagnostic agents to cells. We describe a new type of probe suitable for dual detection methods (spectrophotometric and fluorescence). This aspect makes it unique among currently available probes because allows it to be detected with greater accuracy. We developed a highly fluorescent coumarinated polymer to overcome the limited brightness of conventional dyes with insufficient for long-term photostablility. Hydrophilic dyes (Lucifer yellow, Procion red, Procion blue) are entrapped in the aqueous core of stable polymeric nanocapsules with coumarin 6 embedded in a nanometre-thick poly(styrene-co-divinylbenzene) wall. Target compounds can be incorporated into nanocapsules in a single step. The hydrophilic phospholipids outer shell ensures biocompatibility and facilitates cell penetration. In this way, the novel fluorescent hybrid materials can help of nanotechnology.

  12. A novel approach to arthritis treatment based on resveratrol and curcumin co-encapsulated in lipid-core nanocapsules: In vivo studies.

    PubMed

    Coradini, Karine; Friedrich, Rossana B; Fonseca, Francisco N; Vencato, Marina S; Andrade, Diego F; Oliveira, Cláudia M; Battistel, Ana Paula; Guterres, Silvia S; da Rocha, Maria Izabel U M; Pohlmann, Adriana R; Beck, Ruy C R

    2015-10-12

    Resveratrol and curcumin are two natural polyphenols extensively used due to their remarkable anti-inflammatory activity. The present work presents an inedited study of the in vivo antioedematogenic activity of these polyphenols co-encapsulated in lipid-core nanocapsules on Complete Freund's adjuvant (CFA)-induced arthritis in rats. Lipid-core nanocapsules were prepared by interfacial deposition of preformed polymer. Animals received a single subplantar injection of CFA in the right paw. Fourteen days after arthritis induction, they were treated with resveratrol, curcumin, or both in solution or loaded in lipid-core nanocapsules (1.75 mg/kg/twice daily, i.p.), for 8 days. At the doses used, the polyphenols in solution were not able to decrease paw oedema. However, nanoencapsulation improved the antioedematogenic activity of polyphenols at the same doses. In addition, the treatment with co-encapsulated polyphenols showed the most pronounced effects, where an inhibition of 37-55% was observed between day 16 and 22 after arthritis induction. This treatment minimized most of the histological changes observed, like fibrosis in synovial tissue, cartilage and bone loss. In addition, unlike conventionally arthritis treatment, resveratrol and curcumin co-encapsulated in lipid-core nanocapsules did not alter important hepatic biochemical markers (ALP, AST, and ALT). In conclusion, the strategy of co-encapsulating resveratrol and curcumin in lipid-core nanocapsules improves their efficacy as oedematogenic agents, with no evidence of hepatotoxic effects. This is a promising strategy for the development of new schemes for treatment of chronic inflammation diseases, like arthritis.

  13. [The hygiene of refrigerated and frozen foods].

    PubMed

    Sinell, H J

    1989-04-01

    Health and spoilage hazards arising from refrigerated and deep frozen foods may be due to - raw materials, e.g. pathogenic microorganisms which come from infected living animals or contaminate raw foods during handling. Psychrotrophic organisms have particular significance as pathogens or spoilage organisms as they can multiply also during refrigeration; - improper processing. Temperature abuse and incorrect time/temperature relations are main causes for microorganisms being not destroyed at the expected rate or even getting a chance of multiplying. Proper handling after refrigeration or frozen storage of foods ("hygiene of thawing") deserves also particular attention. - contamination, i.e. initial contamination of raw products which are ready for consumption without further processing (fruits, raw salads). Recontamination which follows a heat process is much more important and occurs before, during and after application of cold. In those cases, again, one has to distinguish between products which (a) are ready for consumption without a process (bakery and confectionary goods, ice cream, drinking milk) and (b) have to pass a process which reduces the bacterial load before consuming the food (ready to eat dishes or other foods ready for reheating in the home). Sites of increased hygienic hazard are a) lack of partitioning "clean" and "unclean" areas and processes, b) defects of sanitation and hygiene of personnel, c) defects of packaging, d) leakage during aseptic filling. Hazards are controlled through product and plant specific analysis of the process flow followed by continuous monitoring the "Critical Control Points". As an example, a report is given on a study on random samples taken from 180.000 prepackaged deep frozen menus which had been produced for a mass meeting. Microbiological monitoring of the process revealed time/temperature relations as critical control points of primary importance. Particular problems arose from any stoppage at the production line

  14. Bacteriological profile of raw, frozen chicken nuggets.

    PubMed

    Eglezos, Sofroni; Dykes, Gary A; Huang, Bixing; Fegan, Narelle; Stuttard, Ed

    2008-03-01

    The bacteriological profile of raw, frozen chicken nuggets manufactured at a chicken processing facility in Queensland, Australia, was determined. Chicken nuggets are manufactured by grinding poultry, adding premixes to incorporate spices, forming the meat to the desired size and shape, applying a batter and breading, freezing, and packaging. A total of 300 frozen batches were analyzed for aerobic plate count, Escherichia coli, and Salmonella over a period of 4 years. The mean of the aerobic plate count was 5.4 log CFU/g, and counts at the 90th, 95th, and 99th percentiles were 5.7, 5.9, and 6.5 log CFU/g, respectively. The maximum number of bacteria detected was 6.6 log CFU/g. E. coli prevalence was 47%, and of the positive samples, the mean was 1.9 log CFU/g; counts at the 90th, 95th, and 99th percentiles were 2.3, 2.4, and 2.8 log CFU/g, respectively. The maximum number of E. coli was 2.9 log CFU/g. The Salmonella prevalence was 8.7%, and 57.7% of these isolates were typed as Salmonella subspecies II 4,12,[27]:b:[e,n,x] (Sofia), a low-virulence serotype well adapted to Australian poultry flocks. There was a significant relationship (P < 0.05) between season and both aerobic plate counts and E. coli counts, and no correlation between E. coli counts and Salmonella prevalence. This study provides valuable data on the bacteriological quality of raw, frozen chicken nuggets.

  15. Imaging radar observations of frozen Arctic lakes

    NASA Technical Reports Server (NTRS)

    Elachi, C.; Bryan, M. L.; Weeks, W. F.

    1976-01-01

    A synthetic aperture imaging L-band radar flown aboard the NASA CV-990 remotely sensed a number of ice-covered lakes about 48 km northwest of Bethel, Alaska. The image obtained is a high resolution, two-dimensional representation of the surface backscatter cross section, and large differences in backscatter returns are observed: homogeneous low returns, homogeneous high returns and/or low returns near lake borders, and high returns from central areas. It is suggested that a low return indicates that the lake is frozen completely to the bottom, while a high return indicates the presence of fresh water between the ice cover and the lake bed.

  16. The effect of irradiation in the quality of the avocado frozen pulp

    NASA Astrophysics Data System (ADS)

    Valdivia, Ma. Ángeles; Bustos, Ma. Emilia; Ruiz, Javier; Ruiz, Luisa F.

    2002-03-01

    The quality of frozen avocado pulp irradiated with 60Co gamma rays at doses of: 0.5, 1.0, 1.5, and 2.5 kGy, was studied. These are possible doses for reducing the content of bacteria Listeria monocytogenes by 1-4 log cycles. The study principally consisted of weekly evaluations of damages caused in lipids and chlorophyll pigment over a period of one year. No significant differences were found in either hydrolysis rancidity or in the oxidative rancidity for any of the doses. The concentrations of fatty acids and peroxides were below those established by Codex Alimentarius. This means that the quality of the oil in the frozen avocado pulp remains acceptable. The kinetic model for the oxidative rancidity is of first order and the shelf life of the product is of about 120 weeks. The concentrations of the fatty acids and of malondialdehyde were not high enough to produce off-flavors. It was also determined that the radiation doses did not influence the chemistry of the chlorophyll. The results were confirmed by the panelists, who accepted irradiated frozen pulp at the highest radiation dose.

  17. Study on radiation preservation of frozen egg liquid

    NASA Astrophysics Data System (ADS)

    Fengmei, Li; Yongbao, Gu; Dianhua, Chen

    2000-03-01

    In this paper the preservation process of γ-irradiated frozen egg liquid has been studied. It shows that the proper absorbed dose is 2 kGy and there is no significant difference in nutrient components, vitamins content between the irradiated frozen egg liquid and the control. A study of a diet including γ-irradiated frozen egg liquid was carried out with 58 volunteers who, during a 70-day test, indicated that the frozen egg liquid exposed to radiation is hygienic and safe.

  18. Microbiology of Specification and Commercial Precooked Frozen Meals.

    DTIC Science & Technology

    Bacteria, *Frozen foods , Coliform bacteria, Microorganisms, Enterobacteriaceae, Escherichia coli, Staphylococcus aureus, Clostridium perfringens...Streptococcus, Salmonella, Molds(Organisms), Yeasts, Food preservation, Cultures(Biology), Standards

  19. Survival of salmonella in processed chicken products during frozen storage.

    PubMed

    Dominguez, Silvia A; Schaffner, Donald W

    2009-10-01

    Frozen chicken products have been identified recently as a cause of salmonellosis. At least eight salmonellosis outbreaks from 1998 to 2008 have implicated undercooked frozen chicken nuggets, strips, and entrees as infection vehicles. Thus, the presence of Salmonella in frozen products may pose an infection risk if the product is improperly cooked. The objective of this study was to assess the survivability of Salmonella during frozen storage (-20 degrees ) when inoculated in processed chicken products. Four Salmonella strains originally isolated from poultry were inoculated into frozen chicken nuggets (fully cooked) and frozen chicken strips (containing raw poultry) at initial populations of 10(4) to 10(5) CFU/g. Survival was assessed during storage at -20 degrees for 16 weeks by measuring bacterial growth on minimal, selective, and nonselective agars. Results indicate that cell populations measured in nonselective agars (plate count agar and plate count agar supplemented with tetracycline) and minimal (M9) agar remained relatively constant during the entire -20 degrees storage period studied (16 weeks) for both chicken nuggets and strips. However, cell populations were significantly (P < 0.05) lower when measured in selective agar (XLT4) during the 16 weeks of frozen storage for both chicken nuggets and strips, suggesting that these cells were structurally injured. The data presented in this study indicate that Salmonella can survive frozen storage when inoculated in frozen, processed chicken products and confirm that microbial counts on selective agar are not representative of the total population of samples subject to freezing.

  20. Frozen Chemistry Effects on Nozzle Performance Simulations

    NASA Technical Reports Server (NTRS)

    Yoder, Dennis A.; Georgiadis, Nicholas J.; O'Gara, Michael R.

    2009-01-01

    Simulations of exhaust nozzle flows are typically conducted assuming the gas is calorically perfect, and typically modeled as air. However the gas inside a real nozzle is generally composed of combustion products whose thermodynamic properties may differ. In this study, the effect of gas model assumption on exhaust nozzle simulations is examined. The three methods considered model the nozzle exhaust gas as calorically perfect air, a calorically perfect exhaust gas mixture, and a frozen exhaust gas mixture. In the latter case the individual non-reacting species are tracked and modeled as a gas which is only thermally perfect. Performance parameters such as mass flow rate, gross thrust, and thrust coefficient are compared as are mean flow and turbulence profiles in the jet plume region. Nozzles which operate at low temperatures or have low subsonic exit Mach numbers experience relatively minor temperature variations inside the nozzle, and may be modeled as a calorically perfect gas. In those which operate at the opposite extreme conditions, variations in the thermodynamic properties can lead to different expansion behavior within the nozzle. Modeling these cases as a perfect exhaust gas flow rather than air captures much of the flow features of the frozen chemistry simulations. Use of the exhaust gas reduces the nozzle mass flow rate, but has little effect on the gross thrust. When reporting nozzle thrust coefficient results, however, it is important to use the appropriate gas model assumptions to compute the ideal exit velocity. Otherwise the values obtained may be an overly optimistic estimate of nozzle performance.

  1. Searching for Frozen Super Earth via Microlensing

    NASA Astrophysics Data System (ADS)

    Batista, V.; Beaulieu, J. P.; Cassan, A.; Coutures, C.; Donatowicz, J.; Fouqué, P.; Kubas, D.; Marquette, J. B.

    2009-04-01

    Microlensing planet hunt is a unique method to probe efficiently for frozen Super Earth orbiting the most common stars of our galaxy. It is nicely complementing the parameter space probed by very high accuracy radial velocity measurements and future space based detections of low mass transiting planets. In order to maximize the planet catch, the microlensing community is engaged in a total cooperation among the different groups (OGLE, MicroFUN, MOA, PLANET/RoboNET) by making the real time data available, and mutual informing/reporting about modeling efforts. Eight planets have been published so far by combinations of the different groups, 4 Jovian analogues, one Neptune and two Super Earth. Given the microlensing detection efficiency, it suggests that these Neptunes/Super Earths may be quite common. Using networks of dedicated 1-2m class telescopes, the microlensing community has entered a new phase of planet discoveries, and will be able to provide constraints on the abundance of frozen Super-Earths in the near future. Statistics about Mars to Earth mass planets, extending to the habitable zone will be achieved with space based wide field imagers (EUCLID) at the horizon 2017.

  2. Modelling infiltration processes in frozen soils

    NASA Astrophysics Data System (ADS)

    Ireson, A. M.; Barbour, L. S.

    2014-12-01

    Understanding the hydrological processes in soils subject to significant freeze-thaw is fraught by "experimental vagaries and theoretical imponderables" (Miller 1980, Applications of soil physics). The infiltration of snowmelt water and the subsequent transmission of unfrozen water during thawing, is governed by hydraulic conductivity values which are changing with both ice and unfrozen water content. Water held within pores is subject to capillary forces, which results in a freezing point depression (i.e. water remains in the liquid state slightly below 0°C). As the temperature drops below zero, water freezes first in the larger pores, and then in progressively smaller pores. Since the larger pores also are the first to empty by drainage, these pores may be air filled during freezing, while smaller water filled pores freeze. This explains why an unsaturated, frozen soil may still have a considerable infiltration capacity. Infiltration into frozen soil is a critical phenomena related to the risk of flooding in the Canadian prairies, controlling the partitioning of snowmelt into either infiltration or runoff. We propose a new model, based on conceptualizing the pore space as a bundle of capillary tubes (with significant differences to the capillary bundle model of Wannatabe and Flury, 2008, WRR, doi:10.1029/2008WR007102) which allows any air-filled macropores to contribute to the potential infiltration capacity of the soil. The patterns of infiltration and water movement during freeze-thaw from the model are compared to field observations from the Canadian prairies and Boreal Plains.

  3. Stability of Frozen Orbits Around Europa

    NASA Astrophysics Data System (ADS)

    Cardoso Dos Santos, Josué; Vilhena de Moraes, R.; Carvalho, J. S.

    2013-05-01

    Abstract (2,250 Maximum Characters): A planetary satellite of interest at the present moment for the scientific community is Europa, one of the four largest moons of Jupiter. There are some missions planned to visit Europa in the next years, for example, Jupiter Europa Orbiter (JEO, NASA) and Jupiter IcyMoon Explorer (JUICE, ESA). In this work we are formulating theories and constructing computer programs to be used in the design of aerospace tasks as regards the stability of artificial satellite orbits around planetary satellites. The studies are related to translational motion of orbits around planetary satellites considering polygenic perturbations due to forces, such as the nonspherical shape of the central body and the perturbation of the third body. The equations of motion will be developed in closed form to avoid expansions in eccentricity and inclination. For a description of canonical formalism are used the Delaunay canonical variables. The canonical set of equations, which are nonlinear differential equations, will be used to study the stability of orbits around Europa. We will use a simplified dynamic model, which considers the effects caused by non-uniform distribution of mass of Europa (J2, J3 and C22) and the gravitational attraction of Jupiter. Emphasis will be given to the case of frozen orbits, defined as having almost constant values of eccentricity, inclination, and argument of pericentre. An approach will be used to search for frozen orbits around planetary satellites and study their stability by applying a process of normalization of Hamiltonian. Acknowledges: FAPESP

  4. Primary Frozen Shoulder Syndrome: Arthroscopic Capsular Release

    PubMed Central

    Arce, Guillermo

    2015-01-01

    Idiopathic adhesive capsulitis, or primary frozen shoulder syndrome, is a fairly common orthopaedic problem characterized by shoulder pain and loss of motion. In most cases, conservative treatment (6-month physical therapy program and intra-articular steroid injections) improves symptoms and restores shoulder motion. In refractory cases, arthroscopic capsular release is indicated. This surgical procedure carries several advantages over other treatment modalities. First, it provides precise and controlled release of the capsule and ligaments, reducing the risk of traumatic complications observed after forceful shoulder manipulation. Second, release of the capsule and the involved structures with a radiofrequency device delays healing, which prevents adhesion formation. Third, the technique is straightforward, and an oral postoperative steroid program decreases pain and allows for a pleasant early rehabilitation program. Fourth, the procedure is performed with the patient fully awake under an interscalene block, which boosts the patient's confidence and adherence to the physical therapy protocol. In patients with refractory primary frozen shoulder syndrome, arthroscopic capsular release emerges as a suitable option that leads to a faster and long-lasting recovery. PMID:26870652

  5. Release profiles and morphological characterization by atomic force microscopy and photon correlation spectroscopy of 99mTechnetium-fluconazole nanocapsules.

    PubMed

    de Assis, Danielle Nogueira; Mosqueira, Vanessa Carla Furtado; Vilela, José Mário Carneiro; Andrade, Margareth Spangler; Cardoso, Valbert Nascimento

    2008-02-12

    Several classes of antifungal have been employed in candidiasis treatment, but patients with advanced immunodeficiency can present unsatisfactory results after therapy. In these cases, high doses of drugs or the use of multiple agents are sometimes used, and hence increasing the risk of serious side effects. Considering theses difficulties, the encapsulation of antifungal agents in nanoparticulate carriers has been used with the objective of modifying the pharmacokinetic of drugs resulting in more efficient treatments with less side effects. The purpose of this work was the preparation, characterization and the investigation of the release profiles of radiolabeled fluconazole nanocapsules. The size, homogeneity and zeta potential of NC preparations were determined with a Zetasizer 3000HS. The morphology and the structural organization were evaluated by atomic force microscopy (AFM). The release study in vitro of NC was evaluated in physiologic solution with or without 70% mouse plasma. The labeling yield of fluconazole with 99mTc was 94% and the radiolabeled drug was stable within 24h period. The encapsulation percentage of 99mTc-fluconazole in PLA-POLOX NC and PLA-PEG NC was approximately of 30%. The average diameter calculated by photon correlation spectroscopy (PCS) varied from 236 to 356 nm, while the average diameter determined by AFM varied from 238 to 411 nm. The diameter/height relation decreased significantly when 25% glutaraldehyde was used for NC fixation on mica. The zeta potential varied from -55 to -69 nm and surface-modified NC showed lower absolute values than conventional NC. The in vitro release of 99mTc-fluconazole in plasma medium of the conventional and surface-modified NC was greater than in saline. The drug release in plasma medium from conventional NC was faster than for surface-modified NC. The results obtained in this work suggest that the nanocapsules containing fluconazole could be used to identify infectious foci, due to the properties

  6. Fate of paclitaxel lipid nanocapsules in intestinal mucus in view of their oral delivery

    PubMed Central

    Groo, Anne-Claire; Saulnier, Patrick; Gimel, Jean-Christophe; Gravier, Julien; Ailhas, Caroline; Benoit, Jean-Pierre; Lagarce, Frederic

    2013-01-01

    The bioavailability of paclitaxel (Ptx) has previously been improved via its encapsulation in lipid nanocapsules (LNCs). In this work, the interactions between LNCs and intestinal mucus are studied because they are viewed as an important barrier to successful oral delivery. The rheological properties of different batches of pig intestinal mucus were studied under different conditions (the effect of hydration and the presence of LNCs). Fluorescence resonance energy transfer (FRET) was used to study the stability of LNCs in mucus at 37°C for at least 3 hours. Diffusion through 223, 446, and 893 μm mucus layers of 8.4, 16.8, and 42 μg/mL Ptx formulated as Taxol® (Bristol-Myers Squibb, Rueil-Malmaison, France) or encapsulated in LNCs (Ptx-LNCs) were investigated. The effect of the size of the LNCs on their diffusion was also investigated (range, 25–110 nm in diameter). Mucus behaves as a non-Newtonian gel with rheofluidifying properties and a flow threshold. The viscous (G″) and elastic (G′) moduli and flow threshold of the two mucus batches varied with water content, but G′ remained below G″. LNCs had no effect on mucus viscosity and flow threshold. The FRET efficiency remained at 78% after 3 hours. Because the destruction of the LNCs would lead to a FRET efficiency below 25%, these results suggest only a slight modification of LNCs after their contact with mucus. The diffusion of Taxol® and Ptx-LNCs in mucus decreases if the mucus layer is thicker. Interestingly, the apparent permeability across mucus is higher for Ptx-LNCs than for Taxol® for drug concentrations of 16.8 and 42 μg/mL Ptx (P<0.05). The diffusion of Ptx-LNCs through mucus is not size-dependent. This study shows that LNCs are stable in mucus, do not change mucus rheological properties, and improve Ptx diffusion at low concentrations, thus making these systems good candidates for Ptx oral delivery. The study of the physicochemical interaction between the LNC surface and its diffusion in

  7. Antibacterial action of lipid nanocapsules containing fatty acids or monoglycerides as co-surfactants.

    PubMed

    Umerska, Anita; Cassisa, Viviane; Matougui, Nada; Joly-Guillou, Marie-Laure; Eveillard, Matthieu; Saulnier, Patrick

    2016-11-01

    Lipid nanocapsules (LNCs) are a new generation of biomimetic nanocarriers obtained via a phase inversion temperature method and have an oily core of medium-chain triglycerides that is surrounded by a shelf containing a lipophilic surfactant (lecithin) and a hydrophilic surfactant macrogol 15-hydroxystearate. The aim of the present study was to produce LNCs with antibacterial activity by replacing lecithin with other lipophilic surface active compounds, namely medium-chain fatty acids and their 1-monoglycerides, which are known to have antimicrobial properties. Fatty acids and monoglycerides were found to affect the properties of LNCs, such as particle size and zeta potential. Incorporation of a co-surfactant decreased significantly particle size (p⩽0.0039). Furthermore, incorporation of either lecithin or fatty acids with at least 10 carbon atoms yielded LNCs with the zeta potential significantly more negative than that of LNCs composed solely of triglycerides and macrogol 15 hydroxystearate (p⩽0.0310). Moreover, they were capable of decreasing the phase inversion temperature. The activity of the LCNs against Gram-positive S. aureus, including a methicillin-resistant strain, increased with increases in the length of the hydrocarbon tail. Monoglyceride-LNCs were found to be more active than the corresponding fatty acids. The opposite behaviour was observed for Gram-negative bacteria, whereby only caproic acid- and caprylic acid-LNCs were found to be active against these organisms. The monoglyceride-LNCs were bactericidal, and they killed in a time-dependent manner. Fatty acid-LNCs killed in a concentration-dependent manner. A haemolysis assay was performed to obtain preliminary information on the safety of the tested LNCs. In the case of fatty acid-LNCs, the concentrations at which bacterial growth was inhibited were similar to the haemolytic concentrations. However, monoglyceride-LNCs showed antibacterial action at concentrations much lower than those at which

  8. A Possible Small Frozen Lake in Utopia Planitia, Mars

    NASA Astrophysics Data System (ADS)

    de Pablo, M. A.; Pacifici, A.; Komatsu, G.

    2008-03-01

    We describe the geomorphological features observed on a MOC-na image (E0402007) that reveal the existence of a possible small frozen lake on the surface of Utopia Planitia. Some of its characteristics are similar to some frozen lakes on the Earth.

  9. 21 CFR 146.126 - Frozen concentrate for colored lemonade.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices and Beverages § 146.126 Frozen concentrate for colored lemonade. (a) Frozen concentrate for... lemonade by § 146.120, except that it is colored with a safe and suitable fruit juice, vegetable juice, or...

  10. 21 CFR 146.126 - Frozen concentrate for colored lemonade.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices and Beverages § 146.126 Frozen concentrate for colored lemonade. (a) Frozen concentrate for... lemonade by § 146.120, except that it is colored with a safe and suitable fruit juice, vegetable juice, or...

  11. 21 CFR 146.126 - Frozen concentrate for colored lemonade.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices and Beverages § 146.126 Frozen concentrate for colored lemonade. (a) Frozen concentrate for... lemonade by § 146.120, except that it is colored with a safe and suitable fruit juice, vegetable juice, or...

  12. Application of manure to frozen ground in Ohio

    USDA-ARS?s Scientific Manuscript database

    Six small watersheds (approximately 1 ha each) at the USDA-ARS North Appalachian Experimental Watershed research station near Coshocton, Ohio were used to evaluate the environmental impacts of applying manure to frozen ground. On frozen, snow-covered ground in February, two watersheds received turk...

  13. Title: Characterizing a Frozen Extrasolar World

    NASA Technical Reports Server (NTRS)

    Skemer, Andrew J.; Morley, Caroline V.; Allers, Katelyn N.; Geballe, Thomas R.; Marley, Mark S.; Fortney, Jonathan J.; Faherty, Jacqueline K.; Bjoraker, Gordon L.

    2016-01-01

    The recently discovered brown dwarf WISE 0855 presents our first opportunity to study an object outside the Solar System that is nearly as cold as our own gas giant planets. However the traditional methodology for characterizing brown dwarfs-near infrared spectroscopy-is not currently feasible as WISE 0855 is too cold and faint. To characterize this frozen extrasolar world we obtained a 4.5-5.2 micrometers spectrum, the same bandpass long used to study Jupiter's deep thermal emission. Our spectrum reveals the presence of atmospheric water vapor and clouds, with an absorption profile that is strikingly similar to Jupiter. The spectrum is high enough quality to allow the investigation of dynamical and chemical processes that have long been studied in Jupiter's atmosphere, but this time on an extrasolar world.

  14. Preparation of frozen sections for analysis.

    PubMed

    Bratthauer, Gary L

    2010-01-01

    The analysis of frozen tissue by antibodies can be accomplished by the quick freezing of a small tissue sample in liquid nitrogen. Super-cooled isopentane can also be used to further the preservation process. Freezing preserves the available proteins in a near-native state for their identification by antibodies raised against naturally folded proteins. The tissues are sectioned onto charged glass slides where they can be optimally fixed in weakly or non-denaturing solutions such as acetone or those that are alcohol-based. Following mild pretreatment steps to allow for antibody use with low background, (the endogenous peroxidase enzyme or oxidative compounds quenched in a hydrogen peroxide solution and available charged sites blocked by incubation in a normal serum solution) the sections are ready for antigen detection.

  15. Lipid nanocapsules functionalized with polyethyleneimine for plasmid DNA and drug co-delivery and cell imaging

    NASA Astrophysics Data System (ADS)

    Skandrani, Nadia; Barras, Alexandre; Legrand, Dominique; Gharbi, Tijani; Boulahdour, Hatem; Boukherroub, Rabah

    2014-06-01

    The paper reports on the preparation of lipid nanocapsules (LNCs) functionalized with poly(ethyleneimine) (PEI) moieties and their successful use as drug and gene delivery systems. The cationic LNCs were produced by a phase inversion process with a nominal size of 25 nm and subsequently modified with PEI chains using a transacylation reaction. The functionalization process allowed good control over the nanoscale particle size (26.2 +/- 3.9 nm) with monodisperse size characteristics (PI < 0.2) and positive surface charge up to +18.7 mV. The PEI-modified LNCs (LNC25-T) displayed good buffering capacity. Moreover, the cationic LNC25-T were able to condense DNA and form complexes via electrostatic interactions in a typical weight ratio-dependent relationship. It was found that the mean diameter of LNC25-T/pDNA complexes increased to ~40-50 nm with the LNC25-T/pDNA ratio from 1 to 500. Gel electrophoresis and cell viability experiments showed that the LNC25-T/pDNA complexes had high stability with no cytotoxicity due to the anchored PEI polymers on the surface of LNCs. Finally, the transfection efficiency of the LNC25-T/pDNA complexes was studied and evaluated on HEK cell lines in comparison with free PEI/pDNA polyplexes. The combination of cationic LNCs with pDNA exhibited more than a 2.8-fold increase in transfection efficiency compared to the standard free PEI/pDNA polyplexes at the same PEI concentrations. Moreover, we have demonstrated that LNC25-T/pDNA loaded with a hydrophobic drug, paclitaxel, showed high drug efficacy. The high transfection efficiency combined with the potential of simultaneous co-delivery of hydrophobic drugs, relatively small size of LNC25-T/pDNA complexes, and fluorescence imaging can be crucial for gene therapy, as small particle sizes may be more favorable for in vivo studies.The paper reports on the preparation of lipid nanocapsules (LNCs) functionalized with poly(ethyleneimine) (PEI) moieties and their successful use as drug and gene

  16. Surface-active monomer as a stabilizer for polyurea nanocapsules synthesized via interfacial polyaddition in inverse miniemulsion.

    PubMed

    Rosenbauer, Eva-Maria; Landfester, Katharina; Musyanovych, Anna

    2009-10-20

    A surface-active monomer, polyisobutylene-succinimide pentamine (Lubrizol U), was used as a stabilizer for synthesizing polyurea nanocapsules with aqueous core via polyaddition at inverse miniemulsion droplet interface. Because of the presence of amine groups in the Lubrizol molecule, it is covalently incorporated into the polymeric interfacial layer after reaction, resulting in more compact (less permeable) capsule shell. The influence of the stabilizer and the monomer concentration on the shell thickness, colloidal stability, average capsule size, and capsule size polydispersity were examined in detail. Different materials, such as a water-soluble fluorescent dye and aqueous dispersion of magnetite nanoparticles with 10 nm in size, were used as inner phase of the polyurea capsules. The encapsulation efficiency was studied using fluorescein as a marker. As an example for biomedical application, the fluorescein-containing capsules were utilized in cell uptake experiments and visualized using fluorescence microscopy.

  17. 76 FR 6603 - Certain Frozen Warmwater Shrimp from Thailand; Notice of Amended Final Results of Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-07

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF COMMERCE International Trade Administration Certain Frozen Warmwater Shrimp from Thailand; Notice of Amended Final... antidumping duty order on certain frozen warmwater shrimp (shrimp) from Thailand. See Certain Frozen...

  18. Content of cadmium and lead in raw, fried and baked commercial frozen fishery products consumed in Poland.

    PubMed

    Winiarska-Mieczan, Anna; Grela, Eugeniusz R

    2017-07-01

    The study aimed to verify whether the consumption of frozen fishery products was safe in terms of Cd and Pb content. The study material was 31 frozen fishery products (15 breaded products and 16 fillets). Immediately before the analyses the products were subject to culinary treatment according to the recommendations of the producer: fried in colza oil or baked in a gas oven. The level of Cd and Pb was determined using the GF AAS method. The analysed frozen products contained on average 14.0 µg Cd kg(-1) and 18.5 µg Pb kg(-1) . Compared to raw products, baked fish contained 56% more Cd and 72% more Pb, whereas fried fish contained 16% more Cd and 15% more Pb. Compared to fried products, baked fish contained 34% more Cd and 49% more Pb. The content of Cd and Pb in the products did not exceed the acceptable standard. However, it cannot be clearly stated which method of culinary treatment of frozen fishery products is the best with regard to the level of Cd and Pb in the final products. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  19. Selective interaction of PEGylated polyglutamic acid nanocapsules with cancer cells in a 3D model of a metastatic lymph node.

    PubMed

    Alonso-Nocelo, Marta; Abellan-Pose, Raquel; Vidal, Anxo; Abal, Miguel; Csaba, Noemi; Alonso, Maria Jose; Lopez-Lopez, Rafael; de la Fuente, Maria

    2016-06-23

    Metastases are the most common reason of cancer death in patients with solid tumors. Lymph nodes, once invaded by tumor cells, act as reservoirs before cancer cells spread to distant organs. To address the limited access of intravenously infused chemotherapeutics to the lymph nodes, we have developed PEGylated polyglutamic acid nanocapsules (PGA-PEG NCs), which have shown ability to reach and to accumulate in the lymphatic nodes and could therefore act as nanotransporters. Once in the lymphatics, the idea is that these nanocapsules would selectively interact with cancer cells, while avoiding non-specific interactions with immune cells and the appearance of subsequent immunotoxicity. The potential of the PGA-PEG NCs, with a mean size of 100 nm and a negative zeta potential, to selectively reach metastatic cancer cells, has been explored in a novel 3D model that mimics an infiltrated lymph node. Our 3D model, a co-culture of cancer cells and lymphocytes, allows performing experiments under dynamic conditions that simulate the lymphatic flow. After perfusion of the nanocarriers, we observe a selective interaction with the tumor cells. Efficacy studies manifest the need to develop specific therapies addressed to treat metastatic cells that can be in a dormant state. We provide evidence of the ability of PGA-PEG NCs to selectively interact with the tumor cells in presence of lymphocytes, highlighting their potential in cancer therapeutics. We also state the importance of designing precise in vitro models that allow performing mechanistic assays, to efficiently develop and evaluate specific therapies to confront the formation of metastasis.

  20. Hesperetin-loaded lipid-core nanocapsules in polyamide: a new textile formulation for topical drug delivery

    PubMed Central

    Menezes, Paula dos Passos; Frank, Luiza Abrahão; Lima, Bruno dos Santos; de Carvalho, Yasmim Maria Barbosa Gomes; Serafini, Mairim Russo; Quintans-Júnior, Lucindo José; Pohlmann, Adriana Raffin; Guterres, Sílvia Stanisçuaski; Araújo, Adriano Antunes de Souza

    2017-01-01

    Chronic venous insufficiency is characterized by chronic reflux disorder of blood from the peripheral to the central vein, with subsequent venous hypertension and resulting changes in the skin. Traditionally, nonsurgical treatments relied on the use of compression therapy, and more recently a variety of flavonoids have been shown to have positive effects. There have also been developments of more effective drug delivery systems using various textiles and nanotechnology to provide new therapeutic options. Our objective was to use nanotechnology to develop a new formulation containing hesperetin (Hst), a substance not previously used in the treatment of chronic venous insufficiency, impregnated into textile fibers as a possible alternative treatment of venous diseases. We prepared the nanocapsules using the interfacial deposition of preformed polymer method with an Hst concentration of 0.5 mg/mL and then characterized the size and distribution of particles. To quantify the Hst in the samples, we developed an analytical method using high-performance liquid chromatography. Studies of encapsulation efficiency (98.81%±0.28%), microscopy, drug release (free-Hst: 104.96%±12.83%; lipid-core nanocapsule-Hst: 69.90%±1.33%), penetration/permeation, drug content (0.46±0.01 mg/mL) and the effect of washing the textile after drug impregnation were performed as part of the study. The results showed that nanoparticles of a suitable size and distribution with controlled release of the drug and penetration/permeation into the skin layers were achieved. Furthermore, it was established that polyamide was able to hold more of the drug, with a 2.54 times higher content than the cotton fiber; after one wash and after five washes, this relation was 2.80 times higher. In conclusion, this is a promising therapeutic alternative to be further studied in clinical trials. PMID:28352176

  1. Antitumor activity and systemic effects of PVM/MA-shelled selol nanocapsules in lung adenocarcinoma-bearing mice

    NASA Astrophysics Data System (ADS)

    de Souza, Ludmilla Regina; Alexandre Muehlmann, Luis; Carneiro Matos, Lívia; Simón-Vázquez, Rosana; Guerreiro Marques Lacava, Zulmira; Maurício Batista De-Paula, Alfredo; Mosiniewicz-Szablewska, Ewa; Suchocki, Piotr; César Morais, Paulo; González-Fernández, África; Nair Báo, Sônia; Bentes Azevedo, Ricardo

    2015-12-01

    Selol is a semi-synthetic compound containing selenite that is effective against cancerous cells and safer for clinical applications in comparison with other inorganic forms of selenite. Recently, we have developed a formulation of poly(methyl vinyl ether-co-maleic anhydride)-shelled selol nanocapsules (SPN), which reduced the proliferative activity of lung adenocarcinoma cells and presented little deleterious effects on normal cells in in vitro studies. In this study, we report on the antitumor activity and systemic effects induced by this formulation in chemically induced lung adenocarcinoma-bearing mice. The in vivo antitumor activity of the SPN was verified by macroscopic quantification, immunohistochemistry and morphological analyses. Toxicity analyses were performed by evaluations of the kidney, liver, and spleen; analyses of hemogram and plasma levels of alanine aminotransferase, aspartate transaminase, urea, and creatinine; and DNA fragmentation and cell cycle activity of the bone marrow cells. Furthermore, we investigated the potential of the SPN formulation to cause hemolysis, activate the complement system, provoke an inflammatory response and change the conformation of the plasma proteins. Our results showed that the SPN reduced the area of the surface tumor nodules but not the total number of tumor nodules. The biochemical and hematological findings were suggestive of the low systemic toxicity of the SPN formulation. The surface properties of the selol nanocapsules point to characteristics that are consistent with the treatment of the tumors in vivo: low hemolytic activity, weak inflammatory reaction with no activation of the complement system, and mild or absent conformational changes of the plasma proteins. In conclusion, this report suggests that the SPN formulation investigated herein exhibits anti-tumoral effects against lung adenocarcinoma in vivo and is associated with low systemic toxicity and high biocompatibility.

  2. Curcumin-loaded lipid-core nanocapsules as a strategy to improve pharmacological efficacy of curcumin in glioma treatment.

    PubMed

    Zanotto-Filho, Alfeu; Coradini, Karine; Braganhol, Elizandra; Schröder, Rafael; de Oliveira, Cláudia Melo; Simões-Pires, André; Battastini, Ana Maria Oliveira; Pohlmann, Adriana Raffin; Guterres, Sílvia Stanisçuaski; Forcelini, Cassiano Mateus; Beck, Ruy Carlos Ruver; Moreira, José Cláudio Fonseca

    2013-02-01

    In this study, we developed curcumin-loaded lipid-core nanocapsules (C-LNCs) in an attempt to improve the antiglioma activity of this polyphenol. C-LNC showed nanotechnological properties such as nanometric mean size (196 nm), 100% encapsulation efficiency, polydispersity index below 0.1, and negative zeta potential. The in vitro release assays demonstrated a controlled release of curcumin from lipid-core nanocapsules. In C6 and U251MG gliomas, C-LNC promoted a biphasic delivery of curcumin: the first peak occurred early in the treatment (1-3h), whereas the onset of the second phase occurred after 48 h. In C6 cells, the cytotoxicity of C-LNC was comparable to non-encapsulated curcumin only after 96 h, whereas C-LNCs were more cytotoxic than non-encapsulated curcumin after 24h of incubation in U251MG. Induction of G2/M arrest and autophagy were observed in C-LNC as well as in free-curcumin treatments. In rats bearing C6 gliomas, C-LNC (1.5mg/kg/day, i.p.) decreased the tumor size and malignance and prolonged animal survival when compared to same dose of non-encapsulated drug. In addition, serum markers of tissue toxicity and histological parameters were not altered. Considered overall, the data suggest that the nanoencapsulation of curcumin in LNC is an important strategy to improve its pharmacological efficacy in the treatment of gliomas. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. World oil

    NASA Astrophysics Data System (ADS)

    Sweeney, J. L.

    1982-06-01

    Results obtained through the application of 10 prominent world oil or world energy models to 12 scenarios are reported. These scenarios were designed to bound the range of likely future world oil market outcomes. Conclusions relate to oil market trends, impacts of policies on oil prices, security of oil supplies, impacts of policies on oil security problems, use of the oil import premium in policymaking, the transition to oil substitutes, and the state of the art of world oil modeling.

  4. Optical property of CR-39 synthesized by doping with methylviologen-encapsulated SiO2 nanocapsules as a solid-state X-ray plate detector

    NASA Astrophysics Data System (ADS)

    Miyoshi, Hirokazu; Kida, Fumio; Yamada, Kenji; Tsuchiya, Koichiro; Hase, Hitoshi

    2016-05-01

    A CR-39 plate synthesized by doping with methylviologen-encapsulated SiO2 nanocapsules was firstly demonstrated as a solid-state X-ray (80 kV) detector for diagnostic examination without etching using an alkali solution. The X-ray-irradiated area was clearly observed as an emission image by exciting with a laser in FLA-9000. The maximum intensity was obtained using a 532 nm laser. The emission intensity at the X-ray-irradiated area increased linearly from 0.5 to 3 Gy with increasing thickness from 1 to 5 mm. In 15-nm-diameter silica nanocapsules and 4-5-mm-thick CR-39, the maximum intensity was observed by X-ray irradiation.

  5. Synthesis of mesoporous SiO2-ZnO nanocapsules: encapsulation of small biomolecules for drugs and "SiOZO-plex" for gene delivery

    NASA Astrophysics Data System (ADS)

    Kumar, Vijay Bhooshan; Annamanedi, Madhavi; Prashad, Muvva Durga; Arunasree, Kalle M.; Mastai, Yitzhak; Gedanken, Aharon; Paik, Pradip

    2013-09-01

    This work presents a new synthesis of mesoporous SiO2-ZnO composite nanocapsules with sizes of 90-150 nm and represents their applications in encapsulation of small biomolecules (fluorescent molecules, drugs, and DNA) for uses in medical biotechnology (e.g., drug and gene delivery) for the first time. The nanocapsule size and morphology have been confirmed through the HRSEM and HRTEM. The mesoporous structure of the novel materials has been confirmed through both BET and HRTEM, and the pore diameter observed to be ca. 2-8 nm with an average diameter of 5.1 nm. The BET surface area of mesoporous SiO2-ZnO was found to be 230 m2 g-1. Three different types of pores were detected through HRTEM: type-I, normal pores in silica matrix, pore with ZnO nanoparticles at the boundary (type-II) and type-III, the pores with tiny ZnO nanoparticles ( 5-7 nm) inside them. To demonstrate the biocompatibility and cell viability of the nanocapsules, normal and cancerous lymphocyte cells have been chosen and investigated in a systematic way. Fluorescent dye (Rhodamine 6G), anticancer drug e.g., Doxorubicin (DOX) were loaded in all types of pores, and EtBr-labeled DNA molecules were loaded efficiently into the mesopores of second and third types of the composite nanocapsules to manifest the characteristic of mesoporous, and to find out its loading efficacy. The release kinetics of Rhodamine 6G and DOX were studied. The results highlight the potential of novel functional mesoporous SiO2-ZnO nanoparticles for using as the carrier of drugs and formation of "SiOZO-plex", a complex of mesoporous SiO2-ZnO with DNA for gene delivery applications.

  6. Haloperidol-loaded lipid-core polymeric nanocapsules reduce DNA damage in blood and oxidative stress in liver and kidneys of rats

    NASA Astrophysics Data System (ADS)

    Roversi, Katiane; Benvegnú, Dalila M.; Roversi, Karine; Trevizol, Fabíola; Vey, Luciana T.; Elias, Fabiana; Fracasso, Rafael; Motta, Mariana H.; Ribeiro, Roseane F.; dos S. Hausen, Bruna; Moresco, Rafael N.; Garcia, Solange C.; da Silva, Cristiane B.; Burger, Marilise E.

    2015-04-01

    Haloperidol (HP) nanoencapsulation improves therapeutic efficacy, prolongs the drug action time, and reduces its motor side effects. However, in a view of HP toxicity in organs like liver and kidneys in addition to the lack of knowledge regarding the toxicity of polymeric nanocapsules, our aim was to verify the influence of HP-nanoformulation on toxicity and oxidative stress markers in the liver and kidneys of rats, also observing the damage caused in the blood. For such, 28 adult male Wistar rats were designated in four experimental groups ( n = 7) and treated with vehicle (C group), free haloperidol suspension (FH group), blank nanocapsules suspension (B-Nc group), and haloperidol-loaded lipid-core nanocapsules suspension (H-Nc group). The nanocapsules formulation presented the size of approximately 250 nm. All suspensions were administered to the animals (0.5 mg/kg/day-i.p.) for a period of 28 days. Our results showed that FH caused damage in the liver, evidenced by increased lipid peroxidation, plasma levels of aspartate aminotransferase, and alanine aminotransferase, as well as decreased cellular integrity and vitamin C levels. In kidneys, FH treatment caused damage to a lesser extent, observed by decreased activity of δ-aminolevulinate dehydratase (ALA-D) and levels of VIT C. In addition, FH treatment was also related to a higher DNA damage index in blood. On the other hand, animals treated with H-Nc and B-Nc did not show damage in liver, kidneys, and DNA. Our study indicates that the nanoencapsulation of haloperidol was able to prevent the sub-chronic toxicity commonly observed in liver, kidneys, and DNA, thus reflecting a pharmacological superiority in relation to free drug.

  7. Caenorhabditis elegans as an alternative in vivo model to determine oral uptake, nanotoxicity, and efficacy of melatonin-loaded lipid-core nanocapsules on paraquat damage.

    PubMed

    Charão, Mariele Feiffer; Souto, Caroline; Brucker, Natália; Barth, Anelise; Jornada, Denise S; Fagundez, Daiandra; Ávila, Daiana Silva; Eifler-Lima, Vera L; Guterres, Silvia S; Pohlmann, Adriana R; Garcia, Solange Cristina

    2015-01-01

    Caenorhabditis elegans is an alternative in vivo model that is being successfully used to assess the pharmacological and toxic effects of drugs. The exponential growth of nanotechnology requires the use of alternative in vivo models to assess the toxic effects of theses nanomaterials. The use of polymeric nanocapsules has shown promising results for drug delivery. Moreover, these formulations have not been used in cases of intoxication, such as in treatment of paraquat (PQ) poisoning. Thus, the use of drugs with properties improved by nanotechnology is a promising approach to overcome the toxic effects of PQ. This research aimed to evaluate the absorption of rhodamine B-labeled melatonin (Mel)-loaded lipid-core nanocapsules (LNC) by C. elegans, the application of this model in nanotoxicology, and the protection of Mel-LNC against PQ damage. The formulations were prepared by self-assembly and characterized by particle sizing, zeta potential, drug content, and encapsulation efficiency. The results demonstrated that the formulations had narrow size distributions. Rhodamine B-labeled Mel-LNC were orally absorbed and distributed in the worms. The toxicity assessment of LNC showed a lethal dose 50% near the highest dose tested, indicating low toxicity of the nanocapsules. Moreover, pretreatment with Mel-LNC significantly increased the survival rate, reduced the reactive oxygen species, and maintained the development in C. elegans exposed to PQ compared to those worms that were either untreated or pretreated with free Mel. These results demonstrated for the first time the uptake and distribution of Mel-LNC by a nematode, and indicate that while LNC is not toxic, Mel-LNC prevents the effects of PQ poisoning. Thus, C. elegans may be an interesting alternative model to test the nanocapsules toxicity and efficacy.

  8. Caenorhabditis elegans as an alternative in vivo model to determine oral uptake, nanotoxicity, and efficacy of melatonin-loaded lipid-core nanocapsules on paraquat damage

    PubMed Central

    Charão, Mariele Feiffer; Souto, Caroline; Brucker, Natália; Barth, Anelise; Jornada, Denise S; Fagundez, Daiandra; Ávila, Daiana Silva; Eifler-Lima, Vera L; Guterres, Silvia S; Pohlmann, Adriana R; Garcia, Solange Cristina

    2015-01-01

    Caenorhabditis elegans is an alternative in vivo model that is being successfully used to assess the pharmacological and toxic effects of drugs. The exponential growth of nanotechnology requires the use of alternative in vivo models to assess the toxic effects of theses nanomaterials. The use of polymeric nanocapsules has shown promising results for drug delivery. Moreover, these formulations have not been used in cases of intoxication, such as in treatment of paraquat (PQ) poisoning. Thus, the use of drugs with properties improved by nanotechnology is a promising approach to overcome the toxic effects of PQ. This research aimed to evaluate the absorption of rhodamine B-labeled melatonin (Mel)-loaded lipid-core nanocapsules (LNC) by C. elegans, the application of this model in nanotoxicology, and the protection of Mel-LNC against PQ damage. The formulations were prepared by self-assembly and characterized by particle sizing, zeta potential, drug content, and encapsulation efficiency. The results demonstrated that the formulations had narrow size distributions. Rhodamine B-labeled Mel-LNC were orally absorbed and distributed in the worms. The toxicity assessment of LNC showed a lethal dose 50% near the highest dose tested, indicating low toxicity of the nanocapsules. Moreover, pretreatment with Mel-LNC significantly increased the survival rate, reduced the reactive oxygen species, and maintained the development in C. elegans exposed to PQ compared to those worms that were either untreated or pretreated with free Mel. These results demonstrated for the first time the uptake and distribution of Mel-LNC by a nematode, and indicate that while LNC is not toxic, Mel-LNC prevents the effects of PQ poisoning. Thus, C. elegans may be an interesting alternative model to test the nanocapsules toxicity and efficacy. PMID:26300641

  9. Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

    PubMed

    Abdelazez, Amro; Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao; Abdelmotaal, Heba; Sami, Rokayya; Meng, Xiang-Chen

    2017-01-01

    Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. (Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture (Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at -18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only.

  10. Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

    PubMed Central

    Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao

    2017-01-01

    Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. (Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture (Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at −18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only. PMID:28691028

  11. Radiation inactivation of foodborne pathogens on frozen seafood products.

    PubMed

    Sommers, Christopher H; Rajkowski, Kathleen T

    2011-04-01

    Foodborne illness due to consumption of contaminated seafood is, unfortunately, a regular occurrence in the United States. Ionizing (gamma) radiation can effectively inactivate microorganisms and extend the shelf life of seafood. In this study, the ability of gamma irradiation to inactivate foodborne pathogens surface inoculated onto frozen seafood (scallops, lobster meat, blue crab, swordfish, octopus, and squid) was investigated. The radiation D(10)-values (the radiation dose needed to inactivate 1 log unit of a microorganism) for Listeria monocytogenes, Staphylococcus aureus, and Salmonella inoculated onto seafood samples that were then frozen and irradiated in the frozen state (-20°C) were 0.43 to 0.66, 0.48 to 0.71, and 0.47 to 0.70 kGy, respectively. In contrast, the radiation D(10)-value for the same pathogens suspended on frozen pork were 1.26, 0.98, and 1.18 kGy for L. monocytogenes, S. aureus, and Salmonella, respectively. The radiation dose needed to inactivate these foodborne pathogens on frozen seafood is significantly lower than that for frozen meat or frozen vegetables.

  12. Morphology-controlled construction of hierarchical hollow hybrid SnO2@TiO2 nanocapsules with outstanding lithium storage

    PubMed Central

    Zhou, Linzong; Guo, Hong; Li, Tingting; Chen, Weiwei; Liu, Lixiang; Qiao, Jinli; Zhang, Jiujun

    2015-01-01

    A novel synthesis containing microwave-assisted HCl etching reaction and precipitating reaction is employed to prepare hierarchical hollow SnO2@TiO2 nanocapsules for anode materials of Li-ion batteries. The intrinsic hollow nanostructure can shorten the lengths for both ionic and electronic transport, enlarge the electrode surface areas, and improving accommodation of the anode volume change during Li insertion/extraction cycling. The hybrid multi-elements in this material allow the volume change to take place in a stepwise manner during electrochemical cycling. In particular, the coating of TiO2 onto SnO2 can enhance the electronic conductivity of hollow SnO2 electrode. As a result, the as-prepared SnO2@TiO2 nanocapsule electrode exhibits a stably reversible capacity of 770 mA hg−1 at 1 C, and the capacity retention can keep over 96.1% after 200 cycles even at high current rates. This approach may shed light on a new avenue for the fast synthesis of hierarchical hollow nanocapsule functional materials for energy storage, catalyst and other new applications. PMID:26482415

  13. Morphology-controlled construction of hierarchical hollow hybrid SnO2@TiO2 nanocapsules with outstanding lithium storage.

    PubMed

    Zhou, Linzong; Guo, Hong; Li, Tingting; Chen, Weiwei; Liu, Lixiang; Qiao, Jinli; Zhang, Jiujun

    2015-10-20

    A novel synthesis containing microwave-assisted HCl etching reaction and precipitating reaction is employed to prepare hierarchical hollow SnO2@TiO2 nanocapsules for anode materials of Li-ion batteries. The intrinsic hollow nanostructure can shorten the lengths for both ionic and electronic transport, enlarge the electrode surface areas, and improving accommodation of the anode volume change during Li insertion/extraction cycling. The hybrid multi-elements in this material allow the volume change to take place in a stepwise manner during electrochemical cycling. In particular, the coating of TiO2 onto SnO2 can enhance the electronic conductivity of hollow SnO2 electrode. As a result, the as-prepared SnO2@TiO2 nanocapsule electrode exhibits a stably reversible capacity of 770 mA hg(-1) at 1 C, and the capacity retention can keep over 96.1% after 200 cycles even at high current rates. This approach may shed light on a new avenue for the fast synthesis of hierarchical hollow nanocapsule functional materials for energy storage, catalyst and other new applications.

  14. Enhancement of cancer therapy efficacy by trastuzumab-conjugated and pH-sensitive nanocapsules with the simultaneous encapsulation of hydrophilic and hydrophobic compounds.

    PubMed

    Chiang, Chih-Sheng; Hu, Shang-Hsiu; Liao, Bang-Jie; Chang, Yuan-Ching; Chen, San-Yuan

    2014-01-01

    Trastuzumab-conjugated pH-sensitive double emulsion nanocapsules (DENCs) stabilized by a single-component Poly (vinyl alcohol) (PVA) with magnetic nanoparticles can be fabricated through a two-step double emulsion process; these nanocapsules can be used to encapsulate hydrophilic doxorubicin (Dox) and hydrophobic paclitaxel (PTX) simultaneously. When PMASH was attached to the shell of the DENCs, enhanced dual drug release of PTX/Dox was detected, specifically in intracellular acidic pH environments. The targeting ability of these Trastuzumab-conjugated DENCs was demonstrated with confocal images, which revealed a significantly elevated cellular uptake in HER-2 overexpressing SkBr3 cells. More importantly, an intravenous injection of this co-delivery system followed by magnetic targeting (MT) chemotherapy suppressed cancer growth in vivo more efficiently than the delivery of either PTX or Dox alone. The integration of the functionalities makes this combination therapy system a powerfully new tool for in vitro/in vivo cancer therapy, especially for in HER-2 positive cancers. Trastuzumab-conjugated pH-sensitive nanocapsules were used in this study for simultaneous targeted delivery of hydrophobic (PTX) and hydrophilic (Dox) anti-cancer agents to HER-2 positive cancer cells. Additional use of magnetic targeting demonstrated superior efficacy of this delivery system compared to PTX or Dox alone. © 2013.

  15. In-depth nanocrystallization enhanced Li-ions batteries performance with nitrogen-doped carbon coated Fe3O4 yolk-shell nanocapsules

    NASA Astrophysics Data System (ADS)

    Wu, Qianhui; Zhao, Rongfang; Liu, Wenjie; Zhang, Xiue; Shen, Xiao; Li, Wenlong; Diao, Guowang; Chen, Ming

    2017-03-01

    In this paper nitrogen-doped carbon-encapsulation Fe3O4 yolk-shell magnetic nanocapsules (Fe3O4@C-N nanocapsules) have been successfully constructed though a facile hydrothermal method and subsequent annealing process. Fe3O4 nanoparticles are completely enclosed in nitrogen-doped carbon shells with void space between the nanoparticle and the shell. The yolk-shell structure allows Fe3O4 nanoparticles to expand freely without breaking the outer carbon shell during the lithiation/delithiation processes. The volume expansion of Fe3O4 results in the in-depth nanocrystallization. Fortunately, the new generated small nanoparticles can increase the capability with the cycle increase due to the unique confinement effect and excellent electronic conductivity of the nitrogen-doped carbon shells. Hence, after 150 cycles, the discharge capacity of Fe3O4@C-N-700 nanocapsules still remained 832 mA h g-1 at 500 mA g-1, which corresponds to 116.7% of the lowest capacity (713 mA h g-1) at the 16th cycle. We believe that the yolk-shell structure is conducive to enhance the capacity of easy pulverization metal oxidation during the charge/discharge processes.

  16. An artemisinin-mediated ROS evolving and dual protease light-up nanocapsule for real-time imaging of lysosomal tumor cell death.

    PubMed

    Huang, Liwei; Luo, Yingping; Sun, Xian; Ju, Huangxian; Tian, Jiangwei; Yu, Bo-Yang

    2017-06-15

    Lysosomes are critical organelles for cellular homeostasis and can be used as potential targets to kill tumor cells from inside. Many photo-therapeutic methods have been developed to overproduce reactive oxygen species (ROS) to trigger lysosomal membrane permeabilization (LMP)-associated cell death pathway. However, these technologies rely on extra irradiation to activate the photosensitizers, which limits the applications in treating deep seated tumors and widespread metastatic lesions. This work reports a multifunctional nanocapsule to achieve targeted lysosomal tumor cell death without irradiation and real-time monitoring of drug effect through encapsulating artemisinin and dual protease light-up nanoprobe in a folate-functionalized liposome. The nanocapsule can be specifically uptaken by tumor cells via folate receptor-mediated endocytosis to enter lysosomes, in which artemisinin reacts with ferrous to generate ROS for LMP-associated cell death. By virtue of confocal fluorescence imaging, the artemisinin location in lysosome, ROS-triggered LMP and ultimate cell apoptosis can be visualized with the cathepsin B and caspase-3 activatable nanoprobe. Notably, the artemisinin-mediated ROS evolving for tumor therapy and real-time therapeutic monitoring were successfully implemented by living imaging in tumor-bearing mice, which broaden the nanocapsule for in vivo theranostics and may offer new opportunities for precise medicine.

  17. Magnetic core-shell nanocapsules with dual-targeting capabilities and co-delivery of multiple drugs to treat brain gliomas.

    PubMed

    Fang, Jen-Hung; Lai, Yen-Ho; Chiu, Tsung-Lang; Chen, You-Yin; Hu, Shang-Hsiu; Chen, San-Yuan

    2014-08-01

    Lactoferrin (Lf)-tethered magnetic double emulsion nanocapsules (Lf-MDCs) are assembled from polyvinyl alcohol (PVA), polyacrylic acid (PAA), and iron oxide (IO) nanoparticles. The core-shell nanostructure of the Lf-MDCs (particle diameters from 100 to 150 nm) can simultaneously accommodate a hydrophilic drug, doxorubicin (Dox), and a hydrophobic drug, curcumin (Cur), in the core and shell, respectively, of the nanocapsules for an efficient drug delivery system. The release patterns of the two drugs can be regulated by manipulating the surface charges and drug-loading ratios, providing the capability for a stepwise adjuvant release to treat cancer cells. The results demonstrate that the dual (Dox+Cur)-drug-loaded nanocapsule can be effectively delivered into RG2 glioma cells to enhance the cytotoxicity against the cells through a synergistic effect. The combined targeting, i.e., magnetic guidance and incorporation of Lf ligands, of these Lf-MDCs results in significantly elevated cellular uptake in the RG2 cells that overexpress the Lf receptor. Interestingly, an intravenous injection of the co-delivered chemotherapeutics follows by magnetic targeting in brain tumor-bearing mice not only achieve high accumulation at the targeted site but also more efficiently suppress cancer growth in vivo than does the delivery of either drug alone. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Poly-N-acryloyl-(l-phenylalanine methyl ester) hollow core nanocapsules facilitate sustained delivery of immunomodulatory drugs and exhibit adjuvant properties.

    PubMed

    Yamala, Anil Kumar; Nadella, Vinod; Mastai, Yitzhak; Prakash, Hridayesh; Paik, Pradip

    2017-09-11

    Polymeric hollow nanocapsules have attracted significant research attention as novel drug carriers and their preparation is of particular concern owing to the feasibility to encapsulate a broad range of drug molecules. This work presents for the first time the synthesis and development of novel poly-N-acryloyl l-phenylalanine methyl ester hollow core nanocapsules (NAPA-HPNs) of avg. size ca. 100-150 nm by the mini-emulsion technique. NAPA-HPNs are biocompatible and capable of encapsulating sodium nitroprusside (SNP) at a rate of ∼1.3 μM per mg of capsules. These NAPA-HPNs + SNP nano-formulations maintained homeostasis of macrophages which carry and facilitate the action of various drug molecules used against various diseases. These NAPA-HPNs also facilitate the prolonged release of a low level of nitric oxide (NO) and enhance the metabolic activities of pro-inflammatory macrophages, which are important for the action of various drugs in body fluids. NAPA-HPN mediated skewing of naïve macrophages toward the M1 phenotype potentially demonstrates its adjuvant action on the innate immune system. These results potentially suggested that NAPA-HPNs can serve both as a carrier of drugs as well as an adjuvant for the immune system. Thus, these nanocapsules could be used for the effective management of various infectious or tumor diseases where immune-stimulation is paramount for treatment.

  19. Morphology-controlled construction of hierarchical hollow hybrid SnO2@TiO2 nanocapsules with outstanding lithium storage

    NASA Astrophysics Data System (ADS)

    Zhou, Linzong; Guo, Hong; Li, Tingting; Chen, Weiwei; Liu, Lixiang; Qiao, Jinli; Zhang, Jiujun

    2015-10-01

    A novel synthesis containing microwave-assisted HCl etching reaction and precipitating reaction is employed to prepare hierarchical hollow SnO2@TiO2 nanocapsules for anode materials of Li-ion batteries. The intrinsic hollow nanostructure can shorten the lengths for both ionic and electronic transport, enlarge the electrode surface areas, and improving accommodation of the anode volume change during Li insertion/extraction cycling. The hybrid multi-elements in this material allow the volume change to take place in a stepwise manner during electrochemical cycling. In particular, the coating of TiO2 onto SnO2 can enhance the electronic conductivity of hollow SnO2 electrode. As a result, the as-prepared SnO2@TiO2 nanocapsule electrode exhibits a stably reversible capacity of 770 mA hg-1 at 1 C, and the capacity retention can keep over 96.1% after 200 cycles even at high current rates. This approach may shed light on a new avenue for the fast synthesis of hierarchical hollow nanocapsule functional materials for energy storage, catalyst and other new applications.

  20. A novel experiment for measuring infiltration into seasonal frozen soil

    NASA Astrophysics Data System (ADS)

    Demand, Dominic; Weiler, Markus

    2016-04-01

    Large parts of the northern hemisphere have at least seasonal frozen soils. Depending on the initial soil water content infiltration capacity can be reduced through pore blockage of ice. Many studies dealing with this topic used numerical modelling for estimating the effect of frozen soils on infiltration. Only a few studies investigated the influences of seasonal frozen soils on infiltration and runoff generation in field experiments. Some authors point out that preferential flow can be an important factor under frozen conditions, but only qualitative information are available so far. A missing methodology makes it hard to measure and quantify infiltration into frozen soils, especially the role of preferential flow. Therefore, a novel multi-method approach for measuring the influences of seasonal frozen soil on infiltration is presented. Sprinkling experiments with a rate of 50 mm/h were performed at frozen soil plots under wet and dry initial conditions in a grassland field site in the Black Forest, Germany. Additionally, two different water temperatures were used for the sprinkling experiments (~2°C and ~10°C). Thermal infrared imagery was tested for continuous, in-situ monitoring of the spatiotemporal soil thermal state during infiltration and the possibility to derive information on water flow. A dye tracer (Brilliant Blue FCF) was added to the infiltrating water and analyzed by image analysis for flow patterns and depth distribution. Thermal infrared imagery and dye tracer were used for the first time in field experiments in frozen soils and were tested for their potential to show the effect of preferential flow under frozen conditions. These information were related to observed soil moisture and temperature profiles measured with capacitance probes in five depths. Furthermore timing and amount of surface runoff was examined for all plots. Brilliant Blue flow patterns and surface runoff were compared against unfrozen soils with similar initial conditions