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Sample records for delivery system loaded

  1. Injectable nanoparticle-loaded hydrogen system for local delivery of sodium alendronate

    NARCIS (Netherlands)

    Posadowska, U.; Parizek, M.; Filova, E.; Wlodarczyk-Biegun, M.K.; Kamperman, M.M.G.; Bacakova, L.; Pamula, E.

    2015-01-01

    Systemic administration of bisphosphonates, e.g. sodium alendronate (Aln) is characterized by extremely low bioavailability and high toxicity. To omit aforementioned drawbacks an injectable system for the intra-bone delivery of Aln based on Aln-loaded nanoparticles (NPs-Aln) suspended in a hydrogel

  2. Design of Nanoparticles Loaded Acyclovir for Controlled Delivery System

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    Shadab Shahsavari

    2015-10-01

    Full Text Available Introduction: The aim of this research was to develop a new drug release systems based on Nanoparticles. In this study, the natural polymer chitosan was used for preparation of nanoparticles due to its unique properties, such as biocompatibility and biodegradability. Methods: The polymeric nano-drug controlled release system has been designed with experimental design D-optimal response surface methodology, for varied variables such as the concentration of acyclovir, concentration ratio of chitosan/ TPP and pH using the ionic gelation method. The nanoparticles were characterized morphologically by scanning electron microcopy (SEM, particle size analyser (DLS for determining size, zeta and PdI, Fourier Transform Infra-Red (FTIR Spectroscopy for determination of structure of nanoparticlesand thermo gravimetric analysis (TGAfor studying thermal behavior. The optimized nanoparticles were characterized. Results: The size of the particles was detected to be 132±24.3 nm; zeta potential was 32±2.87 mV; PdI of particles was 0.159±0.05; and calculated EE% was 85±4.38%. An in-vitro release study of the prepared nanoparticles illustrated that the percentage of acyclovir released from the nanoparticles was 80.17±2.45% within 48 hrs. Conclusion: The optimized nanoparticles according to SEM image, exhibited segregated and non-aggregated nanoparticles with sub-spherical smooth morphology and also the high thermal stability of acyclovir nanoparticles at temperature up to 200°C due to TGA analysis, which indicated a well-established structure of nanoparticles.

  3. Skin Delivery of Kojic Acid-Loaded Nanotechnology-Based Drug Delivery Systems for the Treatment of Skin Aging

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    M. L. Gonçalez

    2013-01-01

    Full Text Available The aging process causes a number of changes in the skin, including oxidative stress and dyschromia. The kojic acid (KA is iron chelator employed in treatment of skin aging, and inhibits tyrosinase, promotes depigmentation. Nanotechnology-based drug delivery systems, such as liquid crystalline systems (LCSs, can modulate drug permeation through the skin and improve the drug activity. This study is aimed at structurally developing and characterizing a kojic acid-loaded LCS, consists of water (W, cetostearyl isononanoate (oil—O and PPG-5-CETETH-20 (surfactant-S and evaluating its in vitro skin permeation and retention. Three regions of the diagram were selected for characterization: A (35% O, 50% S, 15% W, B (30% O, 50% S, 20% W and C (20% O, 50% S, 30% W, to which 2% KA was added. The formulations were subjected to polarized light microscopy, which indicated the presence of a hexagonal mesophase. Texture and bioadhesion assay showed that formulation B is suitable for topical application. According to the results from the in vitro permeation and retention of KA, the formulations developed can modulate the permeation of KA in the skin. The in vitro cytotoxic assays showed that KA-unloaded LCS and KA-loaded LCS didn't present cytotoxicity. PPG-5-CETETH-20-based systems may be a promising platform for KA skin delivery.

  4. Bleomycin Loaded Magnetite Nanoparticles Functionalized by Polyacrylic Acid as a New Antitumoral Drug Delivery System

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    Yue Xu

    2013-01-01

    Full Text Available Objective. To prepare, characterize, and analyze the release behavior of bleomycin-loaded magnetite nanoparticles (BLM-MNPs coated with polyacrylic acid (PAA as a new drug delivery system that can be specifically distributed in the tumor site. Methods. BLM-MNPs coated with PAA were prepared using a solvothermal approach. The particles were characterized using scanning electron microscope (SEM, vibrating sample magnetometer (VSM, and Fourier transform infrared spectroscopy (FTIR. The loading and release behaviors of BLM-MNPs were examined by a mathematical formula and in vitro release profile at pH 7.5. Results. The sphere Fe3O4 nanoparticles with the size of approximately 30 nm exhibit a saturation magnetization of 87 emu/g. The noncoordinated carboxylate groups of PAA confer on the good dispersibility in the aqueous solution and lead to a good loading efficiency of BLM reaching 50% or higher. Approximately 98% of immobilized BLM could be released within 24 h, of which 22.4% was released in the first hour and then the remaining was released slowly and quantitatively in the next 23 hours. Conclusion. BLM-MNPs were prepared and characterized successfully. The particles show high saturation magnetization, high drug loading capacity, and favorable release property, which could contribute to the specific delivery and controllable release of BLM, and the BLM-MNPs could be a potential candidate for the development of treating solid tumors.

  5. Injectable nanoparticle-loaded hydrogel system for local delivery of sodium alendronate.

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    Posadowska, Urszula; Parizek, Martin; Filova, Elena; Wlodarczyk-Biegun, Malgorzata; Kamperman, Marleen; Bacakova, Lucie; Pamula, Elzbieta

    2015-05-15

    Systemic administration of bisphosphonates, e.g. sodium alendronate (Aln) is characterized by extremely low bioavailability and high toxicity. To omit aforementioned drawbacks an injectable system for the intra-bone delivery of Aln based on Aln-loaded nanoparticles (NPs-Aln) suspended in a hydrogel matrix (gellan gum, GG) was developed. Aln was encapsulated in poly(lactide-co-glycolide) (PLGA 85:15) by solid-oil-water emulsification. Drug release tests showed that within 25 days all the encapsulated drug was released from NPs-Aln and the release rate was highest at the beginning and decreased with time. In contrast, by suspending NPs-Aln in a GG matrix, the release rate was significantly lower and more constant in time. The GG-NPs-Aln system was engineered to be easily injectable and was able to reassemble its structure after extrusion as shown by rheological measurements. Invitro studies showed that the GG-NPs-Aln was cytocompatible with MG-63 osteoblast-like cells and it inhibited RANKL-mediated osteoclastic differentiation of RAW 264.7 cells. The injectability, the sustained local delivery of small doses of Aln and the biological activity render the GG-NPs-Aln system promising for the local treatment of osteoporosis and other bone tissue disorders.

  6. Preparation and evaluation of nattokinase-loaded self-double-emulsifying drug delivery system

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    Xiaona Wang

    2015-10-01

    Full Text Available In the present study, we prepared nattokinase-loaded self-double-emulsifying drug delivery system (SDEDDS and investigated its preliminary pharmacodynamics. The type and concentration of oil phase, inner aqueous phase and emulsifier were screened to prepare optimum nattokinase-loaded SDEDDS. Next, the optimum formulations were characterized based on microstructure, volume-weighted mean droplet size, self-emulsifying rate, yield, storage stability, in vitro release and in vivo pharmacodynamics studies. The water/oil/water multiple emulsions exhibited typical multiple structure, with relatively small volume-weighted mean droplet size 6.0 ± 0.7 μm and high self-emulsifying ability (self-emulsifying time <2 min. Encapsulation of nattokinase was up to 86.8 ± 8.2%. The cumulative release of nattokinase within 8 h was about 30%, exhibiting a sustained release effect. The pharmacodynamics study indicated that nattokinase-loaded SDEDDS could significantly prolong the whole blood clotting time in mouse and effectively improve the carrageenan-induced tail thrombosis compared with nattokinase solution. Moreover, we showed that SDEDDS could successfully self-emulsify into water/oil/water multiple emulsions upon dilution in dispersion medium with gentle stirring and effectively protect nattokinase activity in gastric environment. Our findings suggested that SDEDDS could be a promising strategy for peptide and protein drugs by oral administration.

  7. Preparation and characterization of naproxen-loaded electrospun thermoplastic polyurethane nanofibers as a drug delivery system.

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    Akduman, Cigdem; Özgüney, Işık; Kumbasar, E Perrin Akcakoca

    2016-07-01

    The design and production of drug-loaded nanofiber based materials produced by electrospinning is of interest for use in innovative drug delivery systems. In the present study, ultra-fine fiber mats of thermoplastic polyurethane (TPU) containing naproxen (NAP) were successfully prepared by electrospinning from 8 and 10% (w/w) TPU solutions. The amount of NAP in the solutions was 10 and 20% based on the weight of TPU. The collection period of the drug-loaded electrospun TPU fibers was 5, 10 and 20h, and they were characterized by FTIR, DSC and TGA analysis. The morphology of the NAP-loaded electrospun TPU fiber mats was smooth, and the average diameters of these fibers varied between 523.66 and 723.50nm. The release characteristics of these fiber mats were determined by the total immersion method in the phosphate buffer solution at 37°C. It was observed that the collection period in terms of the mat thickness played a major role in the release rate of NAP from the electrospun TPU mats.

  8. Gentamicin loaded PLGA nanoparticles as local drug delivery system for the osteomyelitis treatment.

    Science.gov (United States)

    Posadowska, Urszula; Brzychczy-Włoch, Monika; Pamuła, Elżbieta

    2015-01-01

    Since there are more and more cases of multiresistance among microorganisms, rational use of antibiotics (especially their systemic vs. local application) is of great importance. Here we propose polymeric nanoparticles as locally applied gentamicin delivery system useful in osteomyelitis therapy. Gentamicin sulphate (GS) was encapsulated in the poly(lactide-co-glycolide) (PLGA 85:15) nanoparticles by double emulsification (water/oil/water, W1/O/W2). The nanoparticles were characterized by dynamic light scattering, laser electrophoresis and atomic force microscopy. UV-vis spectroscopy (O-phthaldialdehyde assay, OPA) and Kirby-Bauer tests were used to evaluate drug release and antimicrobial activity, respectively. Physicochemical characterization showed that size, shape and drug solubilization of the nanoparticles mainly depended on GS content and concentration of surface stabilizer (polyvinyl alcohol, PVA). Laser electrophoresis demonstrated negative value of zeta potential of the nanoparticles attributed to PLGA carboxyl end group presence. Drug release studies showed initial burst release followed by prolonged 35-day sustained gentamicin delivery. Agar-diffusion tests performed with pathogens causing osteomyelitis (Staphylococcus aureus and Staphylococcus epidermidis, both reference strains and clinical isolates) showed antibacterial activity of GS loaded nanoparticles (GS-NPs). It can be concluded that GS-NPs are a promising form of biomaterials useful in osteomyelitis therapy.

  9. The application of EDTA in drug delivery systems: doxorubicin liposomes loaded via NH4EDTA gradient

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    Song YZ

    2014-08-01

    Full Text Available Yanzhi Song,1 Zhenjun Huang,1 Yang Song,2 Qingjing Tian,1 Xinrong Liu,1 Zhennan She,1 Jiao Jiao,1 Eliza Lu,3 Yihui Deng11College of Pharmacy, Shenyang Pharmaceutical University, Shenyang, People’s Republic of China; 2Jiangsu Hansoh Pharmaceutical Co., Ltd., Lianyungang, People’s Republic of China; 3Livzon Mabpharm Inc., Zhuhai, People’s Republic of ChinaAbstract: The applications of ethylenediaminetetraacetic acid (EDTA have been expanded from the treatment of heavy metal poisoning to chelation therapies for atherosclerosis, heart disease, and cancers, in which EDTA reduces morbidity and mortality by chelating toxic metal ions. In this study, EDTA was used in a drug delivery system by adopting an NH4EDTA gradient method to load doxorubicin into liposomes with the goal of increasing therapeutic effects and decreasing drug-related cytotoxicity. The particle size of the optimum NH4EDTA gradient liposomes was 79.4±1.87 nm, and the entrapment efficiency was 95.54%±0.59%. In vitro studies revealed that liposomes prepared using an NH4EDTA gradient possessed long-term stability and delayed drug release. The in vivo studies also showed the superiority of the new doxorubicin formulation. Compared with an equivalent drug dose (5 mg/kg prepared by (NH42SO4 gradient, NH4EDTA gradient liposomes showed no significant differences in tumor inhibition ratio, but cardiotoxicity and liposome-related immune organ damage were lower, and no drug-related deaths were observed. These results show that use of the NH4EDTA gradient method to load doxorubicin into liposomes could significantly reduce drug toxicity without influencing antitumor activity.Keywords: NH4EDTA, liposome, doxorubicin, ion gradient, antitumor activity, toxicity

  10. Capsaicin-loaded vesicular systems designed for enhancing localized delivery for psoriasis therapy.

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    Gupta, Ruchi; Gupta, Madhu; Mangal, Sharad; Agrawal, Udita; Vyas, Suresh Prasad

    2016-05-01

    The aim of the current investigation is to evaluate the potential of capsaicin (CAP)-containing liposomes, niosomes and emulsomes in providing localized and controlled delivery, to improve the topical delivery of drug. CAP-bearing systems were prepared by the film hydration method and compared through various in vitro and in vivo parameters. The TEM photographs suggested that the carrier systems were spherical in shape and nanometric in size range. Skin retention studies of CAP from in vitro and in vivo experiments revealed significantly higher accumulation of drug in the case of the emul-gel formulation. Based on the results, we concluded that the emul-gel may be a potential approach for the topical delivery of CAP, for an effective therapy for psoriasis.

  11. Fabrication of functional hollow microspheres constructed from MOF shells: Promising drug delivery systems with high loading capacity and targeted transport

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    Gao, Xuechuan; Hai, Xiao; Baigude, Huricha; Guan, Weihua; Liu, Zhiliang

    2016-11-01

    An advanced multifunctional, hollow metal-organic framework (MOF) drug delivery system with a high drug loading level and targeted delivery was designed and fabricated for the first time and applied to inhibit tumour cell growth. This hollow MOF targeting drug delivery system was prepared via a simple post-synthetic surface modification procedure, starting from hollow ZIF-8 successfully obtained for the first time via a mild phase transformation under solvothermal conditions. As a result, the hollow ZIF-8 exhibits a higher loading capacity for the model anticancer drug 5-fluorouracil (5-FU). Subsequently, 5-FU-loaded ZIF-8 was encapsulated into polymer layers (FA-CHI-5-FAM) with three components: a chitosan (CHI) backbone, the imaging agent 5-carboxyfluorescein (5-FAM), and the targeting reagent folic acid (FA). Thus, an advanced drug delivery system, ZIF-8/5-FU@FA-CHI-5-FAM, was fabricated. A cell imaging assay demonstrated that ZIF-8/5-FU@FA-CHI-5-FAM could target and be taken up by MGC-803 cells. Furthermore, the as-prepared ZIF-8/5-FU@FA-CHI-5-FAM exhibited stronger cell growth inhibitory effects on MGC-803 cells because of the release of 5-FU, as confirmed by a cell viability assay. In addition, a drug release experiment in vitro indicated that ZIF-8/5-FU@FA-CHI-5-FAM exhibited high loading capacity (51%) and a sustained drug release behaviour. Therefore, ZIF-8/5-FU@FA-CHI-5-FAM could provide targeted drug transportation, imaging tracking and localized sustained release.

  12. D, L-Sulforaphane Loaded Fe3O4@ Gold Core Shell Nanoparticles: A Potential Sulforaphane Delivery System.

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    Kheiri Manjili, Hamidreza; Ma'mani, Leila; Tavaddod, Sharareh; Mashhadikhan, Maedeh; Shafiee, Abbas; Naderi-Manesh, Hossein

    2016-01-01

    A novel design of gold-coated iron oxide nanoparticles was fabricated as a potential delivery system to improve the efficiency and stability of d, l-sulforaphane as an anticancer drug. To this purpose, the surface of gold-coated iron oxide nanoparticles was modified for sulforaphane delivery via furnishing its surface with thiolated polyethylene glycol-folic acid and thiolated polyethylene glycol-FITC. The synthesized nanoparticles were characterized by different techniques such as FTIR, energy dispersive X-ray spectroscopy, UV-visible spectroscopy, scanning and transmission electron microscopy. The average diameters of the synthesized nanoparticles before and after sulforaphane loading were obtained ∼ 33 nm and ∼ 38 nm, respectively, when ∼ 2.8 mmol/g of sulforaphane was loaded. The result of cell viability assay which was confirmed by apoptosis assay on the human breast cancer cells (MCF-7 line) as a model of in vitro-cancerous cells, proved that the bare nanoparticles showed little inherent cytotoxicity, whereas the sulforaphane-loaded nanoparticles were cytotoxic. The expression rate of the anti-apoptotic genes (bcl-2 and bcl-xL), and the pro-apoptotic genes (bax and bak) were quantified, and it was found that the expression rate of bcl-2 and bcl-xL genes significantly were decreased when MCF-7 cells were incubated by sulforaphane-loaded nanoparticles. The sulforaphane-loaded into the designed gold-coated iron oxide nanoparticles, acceptably induced apoptosis in MCF-7 cells.

  13. D, L-Sulforaphane Loaded Fe3O4@ Gold Core Shell Nanoparticles: A Potential Sulforaphane Delivery System.

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    Hamidreza Kheiri Manjili

    Full Text Available A novel design of gold-coated iron oxide nanoparticles was fabricated as a potential delivery system to improve the efficiency and stability of d, l-sulforaphane as an anticancer drug. To this purpose, the surface of gold-coated iron oxide nanoparticles was modified for sulforaphane delivery via furnishing its surface with thiolated polyethylene glycol-folic acid and thiolated polyethylene glycol-FITC. The synthesized nanoparticles were characterized by different techniques such as FTIR, energy dispersive X-ray spectroscopy, UV-visible spectroscopy, scanning and transmission electron microscopy. The average diameters of the synthesized nanoparticles before and after sulforaphane loading were obtained ∼ 33 nm and ∼ 38 nm, respectively, when ∼ 2.8 mmol/g of sulforaphane was loaded. The result of cell viability assay which was confirmed by apoptosis assay on the human breast cancer cells (MCF-7 line as a model of in vitro-cancerous cells, proved that the bare nanoparticles showed little inherent cytotoxicity, whereas the sulforaphane-loaded nanoparticles were cytotoxic. The expression rate of the anti-apoptotic genes (bcl-2 and bcl-xL, and the pro-apoptotic genes (bax and bak were quantified, and it was found that the expression rate of bcl-2 and bcl-xL genes significantly were decreased when MCF-7 cells were incubated by sulforaphane-loaded nanoparticles. The sulforaphane-loaded into the designed gold-coated iron oxide nanoparticles, acceptably induced apoptosis in MCF-7 cells.

  14. Galantamine-loaded PLGA nanoparticles, from nano-emulsion templating, as novel advanced drug delivery systems to treat neurodegenerative diseases

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    Fornaguera, C.; Feiner-Gracia, N.; Calderó, G.; García-Celma, M. J.; Solans, C.

    2015-07-01

    Polymeric nanoparticles could be promising drug delivery systems to treat neurodegenerative diseases. Among the various methods of nanoparticle preparation, nano-emulsion templating was used in the present study to prepare galantamine-loaded nano-emulsions by a low-energy emulsification method followed by solvent evaporation to obtain galantamine-loaded polymeric nanoparticles. This approach was found to be suitable because biocompatible, biodegradable and safe nanoparticles with appropriate features (hydrodynamic radii around 20 nm, negative surface charge and stability higher than 3 months) for their intravenous administration were obtained. Encapsulation efficiencies higher than 90 wt% were obtained with a sustained drug release profile as compared to that from aqueous and micellar solutions. The enzymatic activity of the drug was maintained at 80% after its encapsulation into nanoparticles that were non-cytotoxic at the required therapeutic concentration. Therefore, novel galantamine-loaded polymeric nanoparticles have been designed for the first time using the nano-emulsification approach and showed the appropriate features to become advanced drug delivery systems to treat neurodegenerative diseases.Polymeric nanoparticles could be promising drug delivery systems to treat neurodegenerative diseases. Among the various methods of nanoparticle preparation, nano-emulsion templating was used in the present study to prepare galantamine-loaded nano-emulsions by a low-energy emulsification method followed by solvent evaporation to obtain galantamine-loaded polymeric nanoparticles. This approach was found to be suitable because biocompatible, biodegradable and safe nanoparticles with appropriate features (hydrodynamic radii around 20 nm, negative surface charge and stability higher than 3 months) for their intravenous administration were obtained. Encapsulation efficiencies higher than 90 wt% were obtained with a sustained drug release profile as compared to that from

  15. Bacterial ghosts as novel advanced drug delivery systems: antiproliferative activity of loaded doxorubicin in human Caco-2 cells.

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    Paukner, Susanne; Kohl, Gudrun; Lubitz, Werner

    2004-01-08

    Systemic application of anticancer drugs often causes severe toxic side effects. To reduce the undesired effects, advanced drug delivery systems are needed which are based on specific cell targeting vehicles. In this study, bacterial ghosts from Mannheimia haemolytica were used for site-specific delivery of doxorubicin (DOX) to human colorectal adenocarcinoma cells (Caco-2). Bacterial ghosts are non-denatured envelopes of Gram-negative bacteria with fully intact surface structures for specific attachment to mammalian cells. The in vitro release profile of DOX-ghosts demonstrated that the loaded drug was non-covalently associated with the bacterial ghosts and that the drug delivery vehicles themselves represent a slow release system. Adherence studies showed that the M. haemolytica ghosts more efficiently than E. coli ghosts targeted the Caco-2 cells and released the loaded DOX within the cells. Cytotoxicity assays revealed that the DOX-ghosts exhibited potent antiproliferative activities on Caco-2 cells as the DOX associated with ghosts was two magnitude of orders more cytotoxic than free DOX provided in the medium at the same concentrations. Notably, a significant reduction in the cell viability was measured with DOX-ghosts at low DOX concentrations, which had no inhibitory effect when applied as free DOX after incubation for 16 h or when applied at higher concentrations for only 10 min to the cells. As the higher antiproliferative effects of DOX on Caco-2 cells were mediated by the specific drug targeting properties of the bacterial ghosts, the bacterial ghost system represents a novel platform for advanced drug delivery.

  16. Soybean Lecithin Acts as both Absorption Enhancer and Oily Phase in an Insulin-loaded Emulsion System for Transmucosal Delivery

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    An insulin- loaded emulsion system (IES) was developed as a hypoglycaemic drug for transmucosal delivery. The selected formulation was a stable oil/water emulsion system. The particles in the emulsion system were distributed evenly, and the particle size ranged from 20 to 260 nm ( average size: 67.5 nm). Soybean lecithin played an important role in the emulsion system due to its abilities of acting as both absorption enhancer for insulin uptake through sublingual mucosa and oily phase for the emulsion system. The laser confocal scanning microscopic (LCSM) study showed that FITC-labelled insulin could penetrate the sublingual mucosa of rabbits,and the phase diagrams of the emulsion system suggested that soybean lecithin could take the place of oily phase to construct a stable emulsion system even if the traditional oil was absent. The applications of soybean lecithin as pharmaceutical biomaterial were extended for the further usage by present studies.

  17. Phase Transitions of Isotropic to Anisotropic Biocompatible Lipid-Based Drug Delivery Systems Overcoming Insoluble Benznidazole Loading

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    Letícia Streck

    2016-06-01

    Full Text Available Previous studies reported low benznidazole (BNZ loading in conventional emulsions due to the weak interaction of the drug with the most common oils used to produce foods or pharmaceuticals. In this study, we focused on how the type of surfactant, surfactant-to-oil ratio w/w (SOR and oil-to-water ratio w/w (OWR change the phase behavior of different lipid-based drug delivery systems (LBDDS produced by emulsion phase inversion. The surfactant mixture composed of soy phosphatidylcholine and sodium oleate (1:7, w/w, hydrophilic lipophilic balance = 16 stabilized medium chain triglyceride in water. Ten formulations with the clear aspect or less turbid dispersions (five with the SOR ranging from 0.5 to 2.5 and five with the OWR from 0.06 to 0.4 were selected from the phase behavior diagram to assess structural features and drug-loading capacity. The rise in the SOR induced the formation of distinct lipid-based drug delivery systems (nanoemulsions and liquid crystal lamellar type that were identified using rheological measurements and cross-polarized light microscopy images. Clear dispersions of small and narrow droplet-sized liquid-like nanoemulsions, Newtonian flow-type, were produced at SOR from 0.5 to 1.5 and OWR from 0.12 to 0.4, while clear liquid or gel-like liquid crystals were produced at SOR from 1.5 to 2.5. The BNZ loading was improved according to the composition and type of LBDDS produced, suggesting possible drug location among surfactant layers. The cell viability assays proved the biocompatibility for all of the prepared nanoemulsions at SOR less than 1.5 and liquid crystals at SOR less than 2.5, demonstrating their promising features for the oral or parenteral colloidal delivery systems containing benznidazole for Chagas disease treatment.

  18. Phase Transitions of Isotropic to Anisotropic Biocompatible Lipid-Based Drug Delivery Systems Overcoming Insoluble Benznidazole Loading.

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    Streck, Letícia; Sarmento, Víctor H V; Machado, Paula R L; Farias, Kleber J S; Fernandes-Pedrosa, Matheus F; da Silva-Júnior, Arnóbio Antônio

    2016-01-01

    Previous studies reported low benznidazole (BNZ) loading in conventional emulsions due to the weak interaction of the drug with the most common oils used to produce foods or pharmaceuticals. In this study, we focused on how the type of surfactant, surfactant-to-oil ratio w/w (SOR) and oil-to-water ratio w/w (OWR) change the phase behavior of different lipid-based drug delivery systems (LBDDS) produced by emulsion phase inversion. The surfactant mixture composed of soy phosphatidylcholine and sodium oleate (1:7, w/w, hydrophilic lipophilic balance = 16) stabilized medium chain triglyceride in water. Ten formulations with the clear aspect or less turbid dispersions (five with the SOR ranging from 0.5 to 2.5 and five with the OWR from 0.06 to 0.4) were selected from the phase behavior diagram to assess structural features and drug-loading capacity. The rise in the SOR induced the formation of distinct lipid-based drug delivery systems (nanoemulsions and liquid crystal lamellar type) that were identified using rheological measurements and cross-polarized light microscopy images. Clear dispersions of small and narrow droplet-sized liquid-like nanoemulsions, Newtonian flow-type, were produced at SOR from 0.5 to 1.5 and OWR from 0.12 to 0.4, while clear liquid or gel-like liquid crystals were produced at SOR from 1.5 to 2.5. The BNZ loading was improved according to the composition and type of LBDDS produced, suggesting possible drug location among surfactant layers. The cell viability assays proved the biocompatibility for all of the prepared nanoemulsions at SOR less than 1.5 and liquid crystals at SOR less than 2.5, demonstrating their promising features for the oral or parenteral colloidal delivery systems containing benznidazole for Chagas disease treatment.

  19. Phase Transitions of Isotropic to Anisotropic Biocompatible Lipid-Based Drug Delivery Systems Overcoming Insoluble Benznidazole Loading

    Science.gov (United States)

    Streck, Letícia; Sarmento, Víctor H. V.; Machado, Paula R. L.; Farias, Kleber J. S.; Fernandes-Pedrosa, Matheus F.; da Silva-Júnior, Arnóbio Antônio

    2016-01-01

    Previous studies reported low benznidazole (BNZ) loading in conventional emulsions due to the weak interaction of the drug with the most common oils used to produce foods or pharmaceuticals. In this study, we focused on how the type of surfactant, surfactant-to-oil ratio w/w (SOR) and oil-to-water ratio w/w (OWR) change the phase behavior of different lipid-based drug delivery systems (LBDDS) produced by emulsion phase inversion. The surfactant mixture composed of soy phosphatidylcholine and sodium oleate (1:7, w/w, hydrophilic lipophilic balance = 16) stabilized medium chain triglyceride in water. Ten formulations with the clear aspect or less turbid dispersions (five with the SOR ranging from 0.5 to 2.5 and five with the OWR from 0.06 to 0.4) were selected from the phase behavior diagram to assess structural features and drug-loading capacity. The rise in the SOR induced the formation of distinct lipid-based drug delivery systems (nanoemulsions and liquid crystal lamellar type) that were identified using rheological measurements and cross-polarized light microscopy images. Clear dispersions of small and narrow droplet-sized liquid-like nanoemulsions, Newtonian flow-type, were produced at SOR from 0.5 to 1.5 and OWR from 0.12 to 0.4, while clear liquid or gel-like liquid crystals were produced at SOR from 1.5 to 2.5. The BNZ loading was improved according to the composition and type of LBDDS produced, suggesting possible drug location among surfactant layers. The cell viability assays proved the biocompatibility for all of the prepared nanoemulsions at SOR less than 1.5 and liquid crystals at SOR less than 2.5, demonstrating their promising features for the oral or parenteral colloidal delivery systems containing benznidazole for Chagas disease treatment. PMID:27376278

  20. Development, Characterization, and Pharmacodynamic Evaluation of Hydrochlorothiazide Loaded Self-Nanoemulsifying Drug Delivery Systems

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    Pankajkumar S. Yadav

    2014-01-01

    Full Text Available The objective of the current work was to develop optimized self-nanoemulsifying drug delivery systems (SNEDDS and evaluate their in vitro and in vivo performance. The research comprised various studies which includes solubility studies in various vehicles, pseudoternary phase diagram construction, and preparation and characterization of SNEDDS along with in vitro dissolution and in vivo pharmacodynamic profiling. Based on dissolution profile, a remarkable increase in rate of dissolution was observed in comparison with plain drug and marketed formulation. Optimized SNEDDS formulation was composed of Capmul MCM (19.17% w/w, Tween 80 (57.5% w/w, Transcutol P (12.7% w/w, and HCT (4.17% w/w. In vivo pharmacodynamic evaluation in Wistar rats showed considerable increase in pharmacological effect of HCT by SNEDDS formulation as compared with plain HCT.

  1. Preparation and in Vivo Evaluation of a Dutasteride-Loaded Solid-Supersaturatable Self-Microemulsifying Drug Delivery System

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    Min-Soo Kim

    2015-05-01

    Full Text Available The purpose of this study was to prepare a dutasteride-loaded solid-supersaturatable self-microemulsifying drug delivery system (SMEDDS using hydrophilic additives with high oral bioavailability, and to determine if there was a correlation between the in vitro dissolution data and the in vivo pharmacokinetic parameters of this delivery system in rats. A dutasteride-loaded solid-supersaturatable SMEDDS was generated by adsorption of liquid SMEDDS onto Aerosil 200 colloidal silica using a spray drying process. The dissolution and oral absorption of dutasteride from solid SMEDDS significantly increased after the addition of hydroxypropylmethyl cellulose (HPMC or Soluplus. Solid SMEDDS/Aerosil 200/Soluplus microparticles had higher oral bioavailability with 6.8- and 5.0-fold higher peak plasma concentration (Cmax and area under the concentration-time curve (AUC values, respectively, than that of the equivalent physical mixture. A linear correlation between in vitro dissolution efficiency and in vivo pharmacokinetic parameters was demonstrated for both AUC and Cmax values. Therefore, the preparation of a solid-supersaturatable SMEDDS with HPMC or Soluplus could be a promising formulation strategy to develop novel solid dosage forms of dutasteride.

  2. Formulation and evaluation of dorzolamide hydrochloride-loaded nanoparticles as controlled release drug delivery system

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    Azza A Hasan

    2012-01-01

    Full Text Available This study aimed to prepare anti-glaucomatous dorzolamide hydrochloride-(Dorzo loaded nanoparticles as a controlled release system. Eudragit RS 100 (RS and/or RL 100 (RL were used in formulations by an opportunely adapted Quasi-emulsion solvent diffusion technique. The formulations were evaluated in terms of particle size, zeta potential, drug entrapment, and release profile. All formulations showed tiny particle size varying from 114 to 395 nm for RS and 65 to 277 nm for RL. Positive zeta potential was +19 to +32 mV for RS and +23 to +42 mV for RL formulations. It was demonstrated that increasing polymer concentration lead to increase the percentage of drug entrapped in all batches, to a certain extent (drug: polymer 1:4. Nanoparticles prepared using RL showed lower entrapment efficiency than RS. In contrast, increasing the stirring rate resulted in an increase in the percentage of Dorzo entrapped. A prolonged drug release was shown by all the formulations. Increasing the polymer concentration caused a decrease in the release rate. Moreover, it was evident that increasing RL content increased the amount of Dorzo released. Dorzo-loaded nanoparticles could represent promising drug ophthalmic carriers, due to small particle size, positive zeta potential, and sustained release profile; hence, expecting prolonged corneal contact time, more therapeutically efficient, decreased frequency of administration per day, and better patient compliance.

  3. Efficient induction of antimicrobial activity with vancomycin nanoparticle-loaded poly(trimethylene carbonate) localized drug delivery system

    Science.gov (United States)

    Zhang, Yang; Liang, Ruo-jia; Xu, Jiao-jiao; Shen, Li-feng; Gao, Jian-qing; Wang, Xu-ping; Wang, Na-ni; Shou, Dan; Hu, Ying

    2017-01-01

    Surgery and the local placement of an antibiotic are the predominant therapies to treat chronic osteomyelitis. Vancomycin-loaded N-trimethyl chitosan nanoparticles (VCM/TMC NPs) as a potential drug delivery system have high intracellular penetration and effective intracellular antibacterial activity. This study investigated the effects of a biocompatible material, poly(trimethylene carbonate) (PTMC), to increase the sustained effectiveness of an intracellular antibiotic and its potential application in antibiotic delivery. VCM/TMC NP-PTMC was characterized using scanning electron microscopy and Fourier transform infrared spectroscopy to determine the morphology, stability and chemical interaction of the drug with the polymer. Further, the biodegradation, antibacterial activity, protein adsorption, cell proliferation and drug release characteristics were evaluated. In addition, a Staphylococcus aureus-induced osteomyelitis rabbit model was used to investigate the antibiotic activity and bone repair capability of VCM/TMC NP-PTMC. The results showed that the composite beads of VCM/TMC NPs followed a sustained and slow release pattern and had excellent antibacterial activity and a higher protein adsorption and cell proliferation rate than the VCM-PTMC in vitro. Furthermore, VCM/TMC NP-PTMC inhibits bacteria and promotes bone repair in vivo. Thus, VCM/TMC NP-PTMC might be beneficial in periodontal management to reduce the bacterial load at the infection site and promote bone repair.

  4. Development of a Prolonged-Release Drug Delivery System with Magnolol Loaded in Amino-Functionalized Mesoporous Silica

    Directory of Open Access Journals (Sweden)

    Alina Stefanache

    2017-03-01

    Full Text Available Magnolol (MG is a small-molecule neolignan polyphenolic compound isolated from the genus Magnolia. The anti-inflammatory, anti-oxidative, anti-diabetic, anti-tumorgenic, anti-neurodegenerative, anti-depressant and anti-microbial properties of MG are well documented in recent literature. These fascinating multiple biological activities of MG encourage research about the development of new delivery and administration approaches able to maximize its potential benefits. This study describes the amino-functionalization of the SBA-15 (Santa Barbara Amorphous mesoporous matrix by post-synthesis grafting using APTES (3-aminopropyltriethoxysilane and the characterization of amino-functionalized mesoporous silica SBA-15 loaded with MG in order to achieve modified drug delivery systems. The amino-functionalization of silica SBA-15 was carried out by grafting by refluxing in dry toluene. The powders obtained were characterized texturally by Brunauer-Emmett-Teller (BET surface area analysis measurements and morphologically by scanning electron microscopy. MG loading degree in the nanoporous matrix was determined by the HPLC method at λ = 290 nm. Results showed that by grafting the amino groups in the silica SBA-15, we obtained amino-functionalized silica SBA-15 with an ordered structure, with specific surfaces and pore sizes that differ from the original matrix, which was reflected in the amount of MG immobilized and release kinetics profile.

  5. Fast Disintegrating Quercetin-Loaded Drug Delivery Systems Fabricated Using Coaxial Electrospinning

    Directory of Open Access Journals (Sweden)

    Xiao-Yan Li

    2013-10-01

    Full Text Available The objective of this study is to develop a structural nanocomposite of multiple components in the form of core-sheath nanofibres using coaxial electrospinning for the fast dissolving of a poorly water-soluble drug quercetin. Under the selected conditions, core-sheath nanofibres with quercetin and sodium dodecyl sulphate (SDS distributed in the core and sheath part of nanofibres, respectively, were successfully generated, and the drug content in the nanofibres was able to be controlled simply through manipulating the core fluid flow rates. Field emission scanning electron microscope (FESEM images demonstrated that the nanofibres prepared from the single sheath fluid and double core/sheath fluids (with core-to-sheath flow rate ratios of 0.4 and 0.7 have linear morphology with a uniform structure and smooth surface. The TEM images clearly demonstrated the core-sheath structures of the produced nanocomposites. Differential scanning calorimetry (DSC and X-ray diffraction (XRD results verified that quercetin and SDS were well distributed in the polyvinylpyrrolidone (PVP matrix in an amorphous state, due to the favourite second-order interactions. In vitro dissolution studies showed that the core-sheath composite nanofibre mats could disintegrate rapidly to release quercetin within 1 min. The study reported here provides an example of the systematic design, preparation, characterization and application of a new type of structural nanocomposite as a fast-disintegrating drug delivery system.

  6. Diphtheria toxoid loaded poly-(epsilon-caprolactone) nanoparticles as mucosal vaccine delivery systems.

    Science.gov (United States)

    Singh, Jasvinder; Pandit, Sreenivas; Bramwell, Vincent W; Alpar, H Oya

    2006-02-01

    Poly-(epsilon-caprolactone) (PCL), a poly(lactide-co-glycolide) (PLGA)-PCL blend and co-polymer nanoparticles encapsulating diphtheria toxoid (DT) were investigated for their potential as a mucosal vaccine delivery system. The nanoparticles, prepared using a water-in-oil-in-water (w/o/w) double emulsion solvent evaporation method, demonstrated release profiles which were dependent on the properties of the polymers. An in vitro experiment using Caco-2 cells showed significantly higher uptake of PCL nanoparticles in comparison to polymeric PLGA, the PLGA-PCL blend and co-polymer nanoparticles. The highest uptake mediated by the most hydrophobic nanoparticles using Caco-2 cells was mirrored in the in vivo studies following nasal administration. PCL nanoparticles induced DT serum specific IgG antibody responses significantly higher than PLGA. A significant positive correlation between hydrophobicity of the nanoparticles and the immune response was observed following intramuscular administration. The positive correlation between hydrophobicity of the nanoparticles and serum DT specific IgG antibody response was also observed after intranasal administration of the nanoparticles. The cytokine assays showed that the serum IgG antibody response induced is different according to the route of administration, indicated by the differential levels of IL-6 and IFN-gamma. The nanoparticles eliciting the highest IgG antibody response did not necessarily elicit the highest levels of the cytokines IL-6 and IFN-gamma.

  7. Docetaxel-Loaded Chitosan Microspheres as a Lung Targeted Drug Delivery System: In Vitro and in Vivo Evaluation

    Directory of Open Access Journals (Sweden)

    Hao Wang

    2014-02-01

    Full Text Available The aim of this study was to prepare docetaxel-loaded chitosan microspheres and to evaluate their in vitro and in vivo characteristics. Glutaraldehyde crosslinked microspheres were prepared using a water-in-oil emulsification method, and characterized in terms of the morphological examination, particle size distribution, encapsulation ratio, drug-loading coefficient and in vitro release. Pharmacokinetics and biodistribution studies were used to evaluate that microspheres have more advantage than the conventional formulations. The emulsion crosslinking method was simple to prepare microspheres and easy to scale up. The formed microspheres were spherical in shape, with a smooth surface and the size was uniform (9.6 ± 0.8 µm; the encapsulation efficiency and drug loading of prepared microspheres were 88.1% ± 3.5% and 18.7% ± 1.2%, respectively. In vitro release indicated that the DTX microspheres had a well-sustained release efficacy and in vivo studies showed that the microspheres were found to release the drug to a maximum extent in the target tissue (lung. The prepared microspheres were found to possess suitable physico-chemical properties and the particle size range. The sustained release of DTX from microspheres revealed its applicability as drug delivery system to minimize the exposure of healthy tissues while increasing the accumulation of therapeutic drug in target sites.

  8. Bimatoprost-loaded ocular inserts as sustained release drug delivery systems for glaucoma treatment: in vitro and in vivo evaluation.

    Directory of Open Access Journals (Sweden)

    Juçara Ribeiro Franca

    Full Text Available The purpose of the present study was to develop and assess a novel sustained-release drug delivery system of Bimatoprost (BIM. Chitosan polymeric inserts were prepared using the solvent casting method and characterized by swelling studies, infrared spectroscopy, differential scanning calorimetry, drug content, scanning electron microscopy and in vitro drug release. Biodistribution of 99mTc-BIM eye drops and 99mTc-BIM-loaded inserts, after ocular administration in Wistar rats, was accessed by ex vivo radiation counting. The inserts were evaluated for their therapeutic efficacy in glaucomatous Wistar rats. Glaucoma was induced by weekly intracameral injection of hyaluronic acid. BIM-loaded inserts (equivalent to 9.0 µg BIM were administered once into conjunctival sac, after ocular hypertension confirmation. BIM eye drop was topically instilled in a second group of glaucomatous rats for 15 days days, while placebo inserts were administered once in a third group. An untreated glaucomatous group was used as control. Intraocular pressure (IOP was monitored for four consecutive weeks after treatment began. At the end of the experiment, retinal ganglion cells and optic nerve head cupping were evaluated in the histological eye sections. Characterization results revealed that the drug physically interacted, but did not chemically react with the polymeric matrix. Inserts sustainedly released BIM in vitro during 8 hours. Biodistribution studies showed that the amount of 99mTc-BIM that remained in the eye was significantly lower after eye drop instillation than after chitosan insert implantation. BIM-loaded inserts lowered IOP for 4 weeks, after one application, while IOP values remained significantly high for the placebo and untreated groups. Eye drops were only effective during the daily treatment period. IOP results were reflected in RGC counting and optic nerve head cupping damage. BIM-loaded inserts provided sustained release of BIM and seem to be a

  9. Bimatoprost-loaded ocular inserts as sustained release drug delivery systems for glaucoma treatment: in vitro and in vivo evaluation.

    Science.gov (United States)

    Franca, Juçara Ribeiro; Foureaux, Giselle; Fuscaldi, Leonardo Lima; Ribeiro, Tatiana Gomes; Rodrigues, Lívia Bomfim; Bravo, Renata; Castilho, Rachel Oliveira; Yoshida, Maria Irene; Cardoso, Valbert Nascimento; Fernandes, Simone Odília; Cronemberger, Sebastião; Ferreira, Anderson José; Faraco, André Augusto Gomes

    2014-01-01

    The purpose of the present study was to develop and assess a novel sustained-release drug delivery system of Bimatoprost (BIM). Chitosan polymeric inserts were prepared using the solvent casting method and characterized by swelling studies, infrared spectroscopy, differential scanning calorimetry, drug content, scanning electron microscopy and in vitro drug release. Biodistribution of 99mTc-BIM eye drops and 99mTc-BIM-loaded inserts, after ocular administration in Wistar rats, was accessed by ex vivo radiation counting. The inserts were evaluated for their therapeutic efficacy in glaucomatous Wistar rats. Glaucoma was induced by weekly intracameral injection of hyaluronic acid. BIM-loaded inserts (equivalent to 9.0 µg BIM) were administered once into conjunctival sac, after ocular hypertension confirmation. BIM eye drop was topically instilled in a second group of glaucomatous rats for 15 days days, while placebo inserts were administered once in a third group. An untreated glaucomatous group was used as control. Intraocular pressure (IOP) was monitored for four consecutive weeks after treatment began. At the end of the experiment, retinal ganglion cells and optic nerve head cupping were evaluated in the histological eye sections. Characterization results revealed that the drug physically interacted, but did not chemically react with the polymeric matrix. Inserts sustainedly released BIM in vitro during 8 hours. Biodistribution studies showed that the amount of 99mTc-BIM that remained in the eye was significantly lower after eye drop instillation than after chitosan insert implantation. BIM-loaded inserts lowered IOP for 4 weeks, after one application, while IOP values remained significantly high for the placebo and untreated groups. Eye drops were only effective during the daily treatment period. IOP results were reflected in RGC counting and optic nerve head cupping damage. BIM-loaded inserts provided sustained release of BIM and seem to be a promising system

  10. Development of erythropoietin receptor-targeted drug delivery system against breast cancer using tamoxifen-loaded nanostructured lipid carriers

    Directory of Open Access Journals (Sweden)

    Beh CY

    2017-03-01

    Full Text Available Chaw Yee Beh,1 Chee Wun How,1,2 Jhi Biau Foo,2 Jia Ning Foong,3 Gayathri Thevi Selvarajah,3 Abdullah Rasedee1,3 1Laboratory of Vaccines and Immunotherapeutics, Institute of Bioscience, Universiti Putra Malaysia, Serdang, 2Faculty of Pharmacy, MAHSA University, Jenjarom, 3Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang, Malaysia Abstract: Tamoxifen (TAM has been used in the treatment of breast cancers and is supplemented with erythropoietin (EPO to alleviate the cancer-related anemia. The purported deleterious effects caused by the use of EPO with chemotherapeutic agents in the treatment of cancer-related anemia vary across studies and remain controversial. The use of nanoparticles as a drug delivery system has the potential to improve the specificity of anticancer drugs. In this study, we simultaneously incorporated two pharmacological active ingredients in one nanocarrier to develop EPO-conjugated TAM-loaded lipid nanoparticles (EPO-TAMNLC, a targeted delivery system, to enhance the cytotoxic activity while reducing the side effects of the ingredients. The effect of temperature in modulating the thermodynamic parameters associated with the binding of EPO and TAMNLC was assessed using isothermal titration calorimetry, while the unfolding of EPO structure was determined using fluorescence-quenching approach. The association efficiency of EPO and TAMNLC was 55.43%. Unlike binding of albumin to TAMNLC, the binding of EPO to TAMNLC occurred through endothermic and entropy-driven reaction. The EPO-TAMNLC formulation was stable because of the hydrophobic interaction and the high free energy, suggesting the spontaneity of the interactions between EPO and TAMNLC. The EPO-TAMNLC enhanced the in vitro cytotoxicity of TAM to MCF-7 cells. The EPO surface-functionalized TAMNLC could sequentially deliver EPO and TAM as well as improving site-specific delivery of these therapeutic compounds. Keywords: tamoxifen, thermodynamic interaction

  11. Doxorubicin-loaded platelets as a smart drug delivery system: An improved therapy for lymphoma

    Science.gov (United States)

    Xu, Peipei; Zuo, Huaqin; Chen, Bing; Wang, Ruju; Ahmed, Arsalan; Hu, Yong; Ouyang, Jian

    2017-01-01

    Chemotherapy is majorly used for the treatment of many cancers, including lymphoma. However, cytotoxic drugs, utilized in chemotherapy, can induce various side effects on normal tissues because of their non-specific distribution in the body. Natural platelets are used as drug carriers because of their biocompatibility and specific targeting to vascular disorders, such as cancer, inflammation, and thrombosis. In this work, doxorubicin (DOX) was loaded in natural platelets for treatment of lymphoma. Results showed that DOX was loaded into platelets with high drug loading and encapsulation efficiency. DOX did not significantly induce morphological and functional changes in platelets. DOX-platelet facilitated intracellular drug accumulation through “tumor cell-induced platelet aggregation” and released DOX into the medium in a pH-controlled manner. This phenomenon reduced the adverse effects and enhanced the therapeutic efficacy. The growth inhibition of lymphoma Raji cells was enhanced, and the cardiotoxicity of DOX was reduced when DOX was loaded in platelets. DOX-platelet improved the anti-tumor activity of DOX by regulating the expression of apoptosis-related genes. Thus, platelets can serve as potential drug carriers to deliver DOX for clinical treatment of lymphoma. PMID:28198453

  12. Polyelectrolyte Complex Based Interfacial Drug Delivery System with Controlled Loading and Improved Release Performance for Bone Therapeutics

    Directory of Open Access Journals (Sweden)

    David Vehlow

    2016-03-01

    Full Text Available An improved interfacial drug delivery system (DDS based on polyelectrolyte complex (PEC coatings with controlled drug loading and improved release performance was elaborated. The cationic homopolypeptide poly(l-lysine (PLL was complexed with a mixture of two cellulose sulfates (CS of low and high degree of substitution, so that the CS and PLL solution have around equal molar charged units. As drugs the antibiotic rifampicin (RIF and the bisphosphonate risedronate (RIS were integrated. As an important advantage over previous PEC systems this one can be centrifuged, the supernatant discarded, the dense pellet phase (coacervate separated, and again redispersed in fresh water phase. This behavior has three benefits: (i Access to the loading capacity of the drug, since the concentration of the free drug can be measured by spectroscopy; (ii lower initial burst and higher residual amount of drug due to removal of unbound drug and (iii complete adhesive stability due to the removal of polyelectrolytes (PEL excess component. It was found that the pH value and ionic strength strongly affected drug content and release of RIS and RIF. At the clinically relevant implant material (Ti40Nb similar PEC adhesive and drug release properties compared to the model substrate were found. Unloaded PEC coatings at Ti40Nb showed a similar number and morphology of above cultivated human mesenchymal stem cells (hMSC compared to uncoated Ti40Nb and resulted in considerable production of bone mineral. RIS loaded PEC coatings showed similar effects after 24 h but resulted in reduced number and unhealthy appearance of hMSC after 48 h due to cell toxicity of RIS.

  13. Loading of microcontainers for oral drug delivery

    DEFF Research Database (Denmark)

    Marizza, Paolo

    , they are usually degraded before they are absorbed. These combined factors considerably reduce the bioavailability of many active ingredients. Several strategies have been developed to overcome these challenges. One of them are microfabricated drug delivery devices. Microreservoir based-systems are characterized...... of drugs and with the perspective of mass production. In a first instance, the suitability of inkjet printing as filling method was elucidated. Solutions containing furosemide and lipid based formulations of insulin were dispensed into microcontainers. Secondly, this technique was successfully utilized...... to dispense controlled amounts of polymer into microcontainers. Subsequently, polymer filled-containers were loaded with drug. To achieve this, supercritical impregnation technology was successfully employed. Furthermore, in vitro drug dissolution studies showed that the loading yields and the release...

  14. Design, characterization, and biological evaluation of curcumin-loaded surfactant-based systems for topical drug delivery

    Directory of Open Access Journals (Sweden)

    Fonseca-Santos B

    2016-09-01

    Full Text Available Bruno Fonseca-Santos, Aline Martins dos Santos, Camila Fernanda Rodero, Maria Palmira Daflon Gremião, Marlus Chorilli School of Pharmaceutical Sciences, UNESP – São Paulo State University, Araraquara, São Paulo Brazil Abstract: From previous studies, it has been found that curcumin exhibits an anti-inflammatory activity and is being used for the treatment of skin disorders; however, it is hydrophobic and has weak penetrating ability, resulting in poor drug transport through the stratum corneum. The aim of this study was to develop liquid crystalline systems for topical administration of curcumin for the treatment of inflammation. These liquid crystalline systems were developed from oleic acid, polyoxypropylene (5 polyoxyethylene (20 cetyl alcohol, and water as the surfactant, oil phase, and aqueous phase, respectively. These systems were characterized, and polarized light microscopy showed anisotropy with lamellar mesophases (Formulation 1 and hexagonal mesophases (Formulations 2 and 3, which were confirmed by the peak ratio measured using small-angle X-ray scattering. In addition, rheological tests revealed that the formulations exhibited gel-like behavior (G'>G'', as evidenced by the increased G' values that indicate structured systems. Texture profile analysis showed that hexagonal mesophases have high values of hardness, adhesiveness, and compressibility, which indicate structured systems. In vitro studies on bioadhesion revealed that the hexagonal mesophases increased the bioadhesiveness of the systems to the skin of the pig ear. An in vivo inflammation experiment showed that the curcumin-loaded hexagonal mesophase exhibited an anti-inflammatory activity as compared to the positive control (dexamethasone. The results suggest that this system has a potential to be used as a bioadhesive vehicle for the topical administration of curcumin. Therefore, it is possible to conclude that these systems can be used for the optimization of drug

  15. Design, characterization, and biological evaluation of curcumin-loaded surfactant-based systems for topical drug delivery

    Science.gov (United States)

    Fonseca-Santos, Bruno; dos Santos, Aline Martins; Rodero, Camila Fernanda; Gremião, Maria Palmira Daflon; Chorilli, Marlus

    2016-01-01

    From previous studies, it has been found that curcumin exhibits an anti-inflammatory activity and is being used for the treatment of skin disorders; however, it is hydrophobic and has weak penetrating ability, resulting in poor drug transport through the stratum corneum. The aim of this study was to develop liquid crystalline systems for topical administration of curcumin for the treatment of inflammation. These liquid crystalline systems were developed from oleic acid, polyoxypropylene (5) polyoxyethylene (20) cetyl alcohol, and water as the surfactant, oil phase, and aqueous phase, respectively. These systems were characterized, and polarized light microscopy showed anisotropy with lamellar mesophases (Formulation 1) and hexagonal mesophases (Formulations 2 and 3), which were confirmed by the peak ratio measured using small-angle X-ray scattering. In addition, rheological tests revealed that the formulations exhibited gel-like behavior (G′>G″), as evidenced by the increased G′ values that indicate structured systems. Texture profile analysis showed that hexagonal mesophases have high values of hardness, adhesiveness, and compressibility, which indicate structured systems. In vitro studies on bioadhesion revealed that the hexagonal mesophases increased the bioadhesiveness of the systems to the skin of the pig ear. An in vivo inflammation experiment showed that the curcumin-loaded hexagonal mesophase exhibited an anti-inflammatory activity as compared to the positive control (dexamethasone). The results suggest that this system has a potential to be used as a bioadhesive vehicle for the topical administration of curcumin. Therefore, it is possible to conclude that these systems can be used for the optimization of drug delivery systems to the skin. PMID:27660447

  16. Tamoxifen citrate loaded ethosomes for transdermal drug delivery system: preparation and characterization.

    Science.gov (United States)

    Sarwa, Khomendra Kumar; Suresh, Preeti K; Debnath, Manabendra; Ahmad, Mohammad Zaki

    2013-08-01

    Long term tamoxifen citrate therapy is imperative to treat several dermatological and hormonal sensitive disorders. Successful oral and parenteral administration of tamoxifen citrate has been challenging since it undergoes enzymatic degradation and has poor aqueous solubility issues. In the present work, tamoxifen citrate loaded ethosomes were prepared and characterized for transdermal applications. The prepared formulations were characterized for morphological features, particle size distribution, calorimetric attributes, zeta potential and drug entrapment. Permeation profile of prepared ethosomes was compared with liposomes and hydroethonalic solution across cellophane membrane and human cadaver skin. Results of the permeation studies indicate that ethosomes were able to deliver >90% drug within 24 hours of application, while liposomes and hydroethanolic solution delivered only 39.04% and 36.55% respectively. Skin deposition and stability studies are also reported.

  17. 雷公藤甲素纳米载药系统的研究进展%Research progress of triptolide-loaded nanoparticles delivery systems

    Institute of Scientific and Technical Information of China (English)

    杨祥良; 杨亚江; 刘明星; 梅之南; 陈华兵; 郭国宁; 徐辉碧

    2005-01-01

    This paper reviewed the study of triptolide-loaded nano delivery systems (NDOS) in our group during the past. It was investigated for the preparation, characterization, pharmacology and toxicology of solid lipid nanoparticles (SLN), microemulsion and polymeric nanoparticles. The results indicated that the NDS presented more powerful activity and a lower toxicity in comparison with other drug carrier.

  18. Dual-mechanism gastroretentive drug delivery system loaded with an amorphous solid dispersion prepared by hot-melt extrusion.

    Science.gov (United States)

    Vo, Anh Q; Feng, Xin; Pimparade, Manjeet; Ye, Xinyou; Kim, Dong Wuk; Martin, Scott T; Repka, Michael A

    2017-02-28

    In the present study, we aimed to prepare a gastroretentive drug delivery system that would be both highly resistant to gastric emptying via multiple mechanisms and would also potentially induce in situ supersaturation. The bioadhesive floating pellets, loaded with an amorphous solid dispersion, were prepared in a single step of hot-melt extrusion technology. Hydroxypropyl cellulose (Klucel™ MF) and hypromellose (Benecel™ K15M) were used as matrix-forming polymers, and felodipine was used as the model drug. The foam pellets were fabricated based on the expansion of CO2, which was generated from sodium bicarbonate during the melt-extrusion process. A 2(n) full factorial experimental design was utilized to investigate the effects of formulation compositions to the pellet properties. The melt-extrusion process transformed the crystalline felodipine into an amorphous state that was dispersed and "frozen" in the polymer matrix. All formulations showed high porosity and were able to float immediately, without lag time, on top of gastric fluid, and maintained their buoyancy over 12h. The pellet-specific floating force, which could be as high as 4800μN/g, increased significantly during the first hour, and was relatively stable until 9h. The sodium bicarbonate percentage was found to be most significantly effect to the floating force. The ex vivo bioadhesion force of the pellets to porcine stomach mucosa was approximately 5mN/pellet, which was more than five times higher than the gravitation force of the pellet saturated with water. Drug release was well controlled up to 12h in the sink condition of 0.5% sodium lauryl sulphate in 0.1N HCl. The dissolution at 1, 3, 5, and 8h were 5-12%, 25-45%, 55-80%, and ≥75% respectively for all 11 formulations. In biorelevant dissolution medium, a supersaturated solution was formed, and the concentration was maintained at around 2μg/mL, approximately 10-folds higher than that of the pure felodipine. All input factors

  19. Curcumin loaded pH-sensitive hybrid lipid/block copolymer nanosized drug delivery systems.

    Science.gov (United States)

    Jelezova, Ivelina; Drakalska, Elena; Momekova, Denitsa; Shalimova, Natalia; Momekov, Georgi; Konstantinov, Spiro; Rangelov, Stanislav; Pispas, Stergios

    2015-10-12

    Curcumin is a perspective drug candidate with pleiotropic antineoplastic activity, whose exceptionally low aqueous solubility and poor pharmacokinetic properties have hampered its development beyond the preclinical level. A possible approach to overcome these limitations is the encapsulation of curcumin into nano-carriers, incl. liposomes. The present contribution is focused on feasibility of using hybrid pH-sensitive liposomes, whereby curcumin is entrapped as a free drug and as a water soluble inclusion complex with PEGylated tert-butylcalix[4]arene, which allows the drug to occupy both the phospholipid membranes and the aqueous core of liposomes. The inclusion complexes were encapsulated in dipalmithoylphosphathydilcholine:cholesterol liposomes, whose membranes were grafted with a poly(isoprene-b-acrylic acid) diblock copolymer to confer pH-sensitivity. The liposomes were characterized by DLS, ζ-potential measurements, cryo-TEM, curcumin encapsulation efficacy, loading capacity, and in vitro release as a function of pH. Free and formulated curcumin were further investigated for cytotoxicity, apoptosis-induction and caspase-8, and 9 activation in chemosensitive HL-60 and its resistant sublines HL-60/Dox and HL-60/CDDP. Formulated curcumin was superior cytotoxic and apoptogenic agent vs. the free drug. The mechanistic assay demonstrated that the potent proapoptotic effects of pH-sensitive liposomal curcumin presumably mediated via recruitment of both extrinsic and intrinsic apoptotic pathways in both HL-60 and HL-60/CDDP cells.

  20. In vitro comparative evaluation of monolayered multipolymeric films embedded with didanosine-loaded solid lipid nanoparticles: a potential buccal drug delivery system for ARV therapy.

    Science.gov (United States)

    Jones, Elsabé; Ojewole, Elizabeth; Kalhapure, Rahul; Govender, Thirumala

    2014-05-01

    Drug delivery via the buccal route has emerged as a promising alternative to oral drug delivery. Didanosine (DDI) undergoes rapid degradation in the gastrointestinal tract, has a short half-life and low oral bioavailability, making DDI a suitable candidate for buccal delivery. Recent developments in buccal drug delivery show an increased interest toward nano-enabled delivery systems. The advantages of buccal drug delivery can be combined with that of nanoparticulate delivery systems to provide a superior delivery system. The aim of this study was to design and evaluate the preparation of novel nano-enabled films for buccal delivery of DDI. Solid lipid nanoparticles (SLNs) were prepared via hot homogenization followed by ultrasonication and were characterized before being incorporated into nano-enabled monolayered multipolymeric films (MMFs). Glyceryl tripalmitate with Poloxamer 188 was identified as most suitable for the preparation of DDI-loaded SLNs. SLNs with desired particle size (PS) (201 nm), polydispersity index (PDI) (0.168) and zeta potential (-18.8 mV) were incorporated into MMFs and characterized. Conventional and nano-enabled MMFs were prepared via solvent casting/evaporation using Eudragit RS100 and hydroxypropyl methylcellulose. Drug release from the nano-enabled films was found to be faster (56% versus 20% in first hour). Conventional MMFs exhibited higher mucoadhesion and mechanical strength than nano-enabled MMFs. SLNs did not adversely affect the steady state flux (71.63 ± 13.54 µg/cm(2) h versus 74.39 ± 15.95 µg/cm(2) h) thereby confirming the potential transbuccal delivery of DDI using nano-enabled MMFs. Nano-enabled buccal films for delivery of DDI can be successfully prepared, and these physico-mechanical studies serve as a platform for future formulation optimization work in this emerging field.

  1. Vincristine-sulphate-loaded liposome-templated calcium phosphate nanoshell as potential tumor-targeting delivery system.

    Science.gov (United States)

    Thakkar, Hetal Paresh; Baser, Amit Kumar; Parmar, Mayur Prakashbhai; Patel, Ketul Harshadbhai; Ramachandra Murthy, Rayasa

    2012-06-01

    Vincristine-sulfate-loaded liposomes were prepared with an aim to improve stability, reduce drug leakage during systemic circulation, and increase intracellular uptake. Liposomes were prepared by the thin-film hydration method, followed by coating with calcium phosphate, using the sequential addition approach. Prepared formulations were characterized for size, zeta potential, drug-entrapment efficiency, morphology by transmission electron microscopy (TEM), in vitro drug-release profile, and in vitro cell cytotoxicity study. Effect of formulation variables, such as drug:lipid ratio as well as nature and volume of hydration media, were found to affect drug entrapment, and the concentration of calcium chloride in coating was found to affect size and coating efficiency. Size, zeta potential, and TEM images confirmed that the liposomes were effectively coated with calcium phosphate. The calcium phosphate nanoshell exhibited pH-dependent drug release, showing significantly lower release at pH 7.4, compared to the release at pH 4.5, which is the pH of the tumor interstitium. The in vitro cytotoxicity study done on the lung cancer cell line indicated that coated liposomes are more cytotoxic than plain liposomes and drug solution, indicating their potential for intracellular drug delivery. The cell-uptake study done on the lung cancer cell line indicated that calcium-phosphate-coated liposomes show higher cell uptake than uncoated liposomes.

  2. Formulation optimization of Docetaxel loaded self-emulsifying drug delivery system to enhance bioavailability and anti-tumor activity.

    Science.gov (United States)

    Valicherla, Guru R; Dave, Kandarp M; Syed, Anees A; Riyazuddin, Mohammed; Gupta, Anand P; Singh, Akhilesh; Wahajuddin; Mitra, Kalyan; Datta, Dipak; Gayen, Jiaur R

    2016-05-31

    Poor bioavailability of Docetaxel (DCT) arising due to its low aqueous solubility and permeability limits its clinical utility. The aim of the present study was to develop DCT loaded self-emulsified drug delivery systems (D-SEDDS) and evaluate its potential ability to improve the oral bioavailability and therapeutic efficacy of DCT. D-SEDDS were characterized for their in vitro antitumor activity, in situ single pass intestinal perfusion (SPIP), bioavailability, chylomicron flow blocking study and bio-distribution profile. The D-SEDDS were prepared using Capryol 90, Vitamin E TPGS, Gelucire 44/14 and Transcutol HP with a ratio of 32.7/29.4/8.3/29.6 using D-Optimal Mixture Design. The solubility of DCT was improved upto 50 mg/mL. The oral bioavailability of the D-SEDDS in rats (21.84 ± 3.12%) was increased by 3.19 fold than orally administered Taxotere (6.85 ± 1.82%). The enhanced bioavailability was probably due to increase in solubility and permeability. In SPIP, effective permeability of D-SEDDS was significantly higher than Taxotere. D-SEDDS showed 25 fold more in vitro cytotoxic activity compared to free DCT. Chylomicron flow blocking study and tissue distribution demonstrated the intestinal lymphatic transport of D-SEDDS and higher retention in tumor than Taxotere. The data suggests that D-SEDDS showed desired stability, enhanced oral bioavailability and in vitro antitumor efficacy.

  3. Self-nanoemulsifying drug delivery systems for oral insulin delivery

    DEFF Research Database (Denmark)

    Li, Ping; Tan, Angel; Prestidge, Clive A

    2014-01-01

    This study aims at evaluating the combination of self-nanoemulsifying drug delivery systems (SNEDDS) and enteric-coated capsules as a potential delivery strategy for oral delivery of insulin. The SNEDDS preconcentrates, loaded with insulin-phospholipid complex at different levels (0, 2.5 and 10% w...

  4. Bioavailability Enhancement of Paclitaxel via a Novel Oral Drug Delivery System: Paclitaxel-Loaded Glycyrrhizic Acid Micelles

    Directory of Open Access Journals (Sweden)

    Fu-Heng Yang

    2015-03-01

    Full Text Available Paclitaxel (PTX, taxol, a classical antitumor drug against a wide range of tumors, shows poor oral bioavailability. In order to improve the oral bioavailability of PTX, glycyrrhizic acid (GA was used as the carrier in this study. This was the first report on the preparation, characterization and the pharmacokinetic study in rats of PTX-loaded GA micelles The PTX-loaded micelles, prepared with ultrasonic dispersion method, displayed small particle sizes and spherical shapes. Differential scanning calorimeter (DSC thermograms indicated that PTX was entrapped in the GA micelles and existed as an amorphous state. The encapsulation efficiency was about 90%, and the drug loading rate could reach up to 7.90%. PTX-loaded GA micelles displayed a delayed drug release compared to Taxol in the in vitro release experiment. In pharmacokinetic study via oral administration, the area under the plasma concentration-time curve (AUC0→24 h of PTX-loaded GA micelles was about six times higher than that of Taxol (p < 0.05. The significant oral absorption enhancement of PTX from PTX-loaded GA micelles could be largely due to the increased absorption in jejunum and colon intestine. All these results suggested that GA would be a promising carrier for the oral delivery of PTX.

  5. Novel Drug Delivery System Based on Docetaxel-Loaded Nanocapsules as a Therapeutic Strategy Against Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Antonia Aránega

    2012-04-01

    Full Text Available 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 IC50 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.

  6. Fabrication and evaluation of curcumin-loaded nanoparticles based on solid lipid as a new type of colloidal drug delivery system

    Directory of Open Access Journals (Sweden)

    J Chen

    2013-01-01

    Full Text Available Curcumin has very broad spectrum of biological activities; however, photodegradation, short half-life and low bioavailability have limited its clinical application. Curcumin-loaded solid lipid nanoparticles were studied to overcome these problems. The aim of this study was to optimize the best formulation on curcumin-loaded solid lipid nanoparticles. Emulsion-evaporation and low temperature-solidification technique was applied with monostearin as lipid carriers. The single factor analysis and orthogonal design were used to optimize formulation and various parameters were investigate. By the optimisation of a single factor analysis and orthogonal test, the particles size, polydispersity index, zeta potential, encapsulation efficiency and drug loading capacity of the optimised formulation were 99.99 nm, 0.158, −19.9 mV, 97.86%, and 4.35%, respectively. The differential scanning calorimetry and X-ray diffraction analysis results demonstrated new structure was formed in nanoparticles. The release kinetics in vitro demonstrated curcumin-loaded solid lipid nanoparticles can control drug release. These studies confirmed that curcumin-loaded solid lipid nanoparticles could be prepared successfully with high drug entrapment efficiency and loading capacity. Curcumin-loaded solid lipid nanoparticles may be a promising drug delivery system to control drug release and improve bioavailability.

  7. SYSTEMIC DELIVERY OF DICLOFENAC SODIUM AFTER TOPICAL APPLICATION OF GELS INCORPORATED WITH DRUG-LOADED SOLID LIPID NANOPARTICLES (SLN

    Directory of Open Access Journals (Sweden)

    NARESH GADDAM JITHAN AUKUNURU

    2013-09-01

    Full Text Available The aim of this study was to prepare and evaluate gels incorporating solid lipid nanoparticles (SLNs of diclofenac sodium for systemic delivery of the active after topical application. SLNs were prepared using hot homogenization followed by sonication technique and these were incorporated into freshly prepared carbopol gel. Three different gel formulations (DSL1, DSL2 and DSL3 were prepared and characterized for particle size, charge, viscosity, morphology, and drug-lipid compatibility. The gels were evaluated for in vitro drug release, ex vivo permeation studies and in vivo absorption. The gels enriched with SLN sustained the drug release for 24 h both in vitro and in vivo. The results suggest enhancement in systemic delivery of diclofenac sodium with gels incorporating SLNs.

  8. On-chip microreactor system for the production of nano-emulsion loaded liposomes: towards targeted delivery of lipophilic drugs

    NARCIS (Netherlands)

    Langelaan, M.L.P.; Emmelkamp, J.; Segers, M.J.A.; Lenting, H.B.M.

    2011-01-01

    An on-chip microreactor system for the production of novel nano-biodevices is presented. This nano-biodevice consists of a nano-emulsion loaded with lipophilic drugs, entrapped in liposomes. These nano-biodevices can be equipped with targeting molecules for higher drug efficiency. The microreactor s

  9. Design and Concept of Polyzwitterionic Copolymer Microgel Drug Delivery Systems In Situ Loaded with Non-steroidal Anti-inflammatory Ibuprofen.

    Science.gov (United States)

    Kostova, Bistra; Kamenska, Elena; Georgieva, Dilyana; Balashev, Konstantin; Rachev, Dimitar; Georgiev, George

    2017-01-01

    Nowadays, the modern pharmaceutical investigations are directed toward obtaining of new polymer micro- and nano-sized drug delivery carriers. In this respect, the use of hydrogel carriers based on polyzwitterions (PZIs) is an opportunity in the preparation of polymer drug delivery systems with desired characteristics. This paper describes the synthesis and characterization of micro-structured p(VA-co-DMAPS) systems with different compositions in situ loaded with Ibuprofen by emulsifier-free emulsion copolymerization (EEC) in water. The mean size of the prepared microparticles was measured by SEM and particles have been visualized by AFM. The inclusion of Ibuprofen in the polyzwitterionic copolymer microgel systems was established by using DSC. In vitro drug release experiments were carried out in order to estimate the ability of the obtained microgels to modify the release of water-insoluble Ibuprofen.

  10. Fabrication and loading of microcontainers for oral drug delivery

    DEFF Research Database (Denmark)

    Petersen, Ritika Singh

    is achieved. Characterization of spin coating of drug-polymer films is thoroughly performed using microscopy, profilometry, differential scanning calorimetry, Raman spectroscopy, X-ray diffraction and microdissolution release tests. These films are applied for loading of microcontainers. Furosemide which......Oral drug delivery is considered as the most patient compliant delivery route. However, it faces many obstacles, especially due to the ever-increasing number of drugs that are poorly soluble and barely absorbed in the gastro-intestinal tract. Moreover, drugs can degrade in the harsh acidic...... environment of stomach before they reach the intestine. These issues lead to reduced bioavailability of active ingredients. To combat that novel oral drug delivery systems have been developed. Some of these systems that have gained significant interest in this field are reservoir based drug delivery...

  11. Dual-functional transdermal drug delivery system with controllable drug loading based on thermosensitive poloxamer hydrogel for atopic dermatitis treatment

    Science.gov (United States)

    Wang, Wenyi; Wat, Elaine; Hui, Patrick C. L.; Chan, Ben; Ng, Frency S. F.; Kan, Chi-Wai; Wang, Xiaowen; Hu, Huawen; Wong, Eric C. W.; Lau, Clara B. S.; Leung, Ping-Chung

    2016-04-01

    The treatment of atopic dermatitis (AD) has long been viewed as a problematic issue by the medical profession. Although a wide variety of complementary therapies have been introduced, they fail to combine the skin moisturizing and drug supply for AD patients. This study reports the development of a thermo-sensitive Poloxamer 407/Carboxymethyl cellulose sodium (P407/CMCs) composite hydrogel formulation with twin functions of moisture and drug supply for AD treatment. It was found that the presence of CMCs can appreciably improve the physical properties of P407 hydrogel, which makes it more suitable for tailored drug loading. The fabricated P407/CMCs composite hydrogel was also characterized in terms of surface morphology by field emission scanning electron microscopy (FE-SEM), rheological properties by a rheometer, release profile in vitro by dialysis method and cytotoxicity test. More importantly, the findings from transdermal drug delivery behavior revealed that P407/CMCs showed desirable percutaneous performance. Additionally, analysis of cytotoxicity test suggested that P407/CMCs composite hydrogel is a high-security therapy for clinical trials and thus exhibits a promising way to treat AD with skin moisturizing and medication.

  12. Topical Application of Retinyl Palmitate-Loaded Nanotechnology-Based Drug Delivery Systems for the Treatment of Skin Aging

    Directory of Open Access Journals (Sweden)

    Marcela B. Oliveira

    2014-01-01

    Full Text Available The objective of this study was to perform a structural characterization and evaluate the in vitro safety profile and in vitro antioxidant activity of liquid crystalline systems (LCS with and without retinyl palmitate (RP. LCS containing polyether functional siloxane (PFS as a surfactant, silicon glycol copolymer (SGC as oil phase, and water in the ratios 30 : 25 : 45 and 40 : 50 : 10 with (OLSv = RP-loaded opaque liquid system and TLSv = RP-loaded transparent liquid system, respectively and without (OLS and TLS, respectively RP were studied. Samples were characterized using polarized light microscopy (PLM and rheology analysis. In vitro safety profile was evaluated using red cell hemolysis and in vitro cytotoxicity assays. In vitro antioxidant activity was performed by the DPPH method. PLM analysis showed the presence of lamellar LCS just to TLS. Regardless of the presence of RP, the rheological studies showed the pseudoplastic behavior of the formulations. The results showed that the incorporation of RP in LCS improved the safety profile of the drug. In vitro antioxidant activity suggests that LCS presented a higher capacity to maintain the antioxidant activity of RP. PFS-based systems may be a promising platform for RP topical application for the treatment of skin aging.

  13. Project delivery system (PDS)

    CERN Document Server

    2001-01-01

    As business environments become increasingly competitive, companies seek more comprehensive solutions to the delivery of their projects. "Project Delivery System: Fourth Edition" describes the process-driven project delivery systems which incorporates the best practices from Total Quality and is aligned with the Project Management Institute and ISO Quality Standards is the means by which projects are consistently and efficiently planned, executed and completed to the satisfaction of clients and customers.

  14. Docetaxel (DTX)-loaded polydopamine-modified TPGS-PLA nanoparticles as a targeted drug delivery system for the treatment of liver cancer.

    Science.gov (United States)

    Zhu, Dunwan; Tao, Wei; Zhang, Hongling; Liu, Gan; Wang, Teng; Zhang, Linhua; Zeng, Xiaowei; Mei, Lin

    2016-01-01

    Polydopamine-based surface modification is a simple way to functionalize polymeric nanoparticle (NP) surfaces with ligands and/or additional polymeric layers. In this work, we developed DTX-loaded formulations using polydopamine-modified NPs synthesized using D-α-tocopherol polyethylene glycol 1000 succinate-poly(lactide) (pD-TPGS-PLA/NPs). To target liver cancer cells, galactosamine was conjugated on the prepared NPs (Gal-pD-TPGS-PLA/NPs) to enhance the delivery of DTX via ligand-mediated endocytosis. The size and morphology of pD-TPGS-PLA/NPs and Gal-pD-TPGS-PLA/NPs changed obviously compared with TPGS-PLA/NPs. In vitro studies showed that TPGS-PLA/NPs, pD-TPGS-PLA/NPs and Gal-pD-TPGS-PLA/NPs had similar release profiles of DTX. Both confocal laser scanning microscopy and flow cytometric results showed that coumarin 6-loaded Gal-pD-TPGS-PLA/NPs had the highest cellular uptake efficiency in liver cancer cell line HepG2. Moreover, DTX-loaded Gal-pD-TPGS-PLA/NPs inhibited the growth of HepG2 cells more potently than TPGS-PLA/NPs, pD-TPGS-PLA/NPs, and a clinically available DTX formulation (Taxotere®). The in vivo biodistribution experiments show that the Gal-pD-TPGS-PLA/NPs are specifically targeted to the tumor. Furthermore, the in vivo anti-tumor effects study showed that injecting DTX-loaded Gal-pD-TPGS-PLA/NPs reduced the tumor size most significantly on hepatoma-bearing nude mice. These results suggest that Gal-pD-TPGS-PLA/NPs prepared in the study specifically interacted with the hepatocellular carcinoma cells through ligand-receptor recognition and they may be used as a potentially eligible drug delivery system targeting liver cancers. Polydopamine-based surface modification is a simple way to functionalize polymeric nanoparticle surfaces with ligands and/or additional polymeric layers. In this work, we developed docetaxel (DTX)-loaded formulations using polydopamine-modified NPs synthesized from D-α-tocopherol polyethylene glycol 1000 succinate

  15. Quality by design of curcumin-loaded calcium alginate emulsion beads as an oral controlled release delivery system

    Directory of Open Access Journals (Sweden)

    Mayyas Al-Remawi

    2015-03-01

    Full Text Available The aim of the study was to prepare a curcumin floating bead system to act as an oral controlled release delivery system. The methodology includes the use of calcium alginate emulsion beads which contains two important ingredients oleic acid and Tween® 80. The ingredient effect was assessed in terms of curcumin release and gel stability. The formulations with higher concentrations of oleic acid were found to be more stable and selected for further analysis. The drug release mechanism was also evaluated in simulated gastric fluid. Response surface methodology was used to determine the optimum conditions for preparation in terms of floating time and curcumin release. Two factors were assessed i.e. the crosslinking time and Tween 80 concentration. It was found that both factors were affecting the floating time and drug release. The optimum conditions for the preparation of curcumin beads were determined and tested. The observed and predicted responses of the optimum curcumin bead formulation were almost the same

  16. Preparation and evaluation of a self-nanoemulsifying drug delivery system loaded with Akebia saponin D–phospholipid complex

    Directory of Open Access Journals (Sweden)

    Shen J

    2016-09-01

    Full Text Available Jinyang Shen,1 Jianping Bi,2 Hongli Tian,1 Ye Jin,1 Yuan Wang,3 Xiaolin Yang,4 Zhonglin Yang,1 Junping Kou,5 Fei Li1 1State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 2Shandong Provincial Traditional Chinese Medical Hospital & Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, 3Traditional Chinese Medical Hospital of Pukou District, 4Key Laboratory of Pharmaceutical and Biological Marine Resources Research and Development of Jiangsu Province, Nanjing University of Chinese Medicine, 5Jiangsu Key Laboratory of TCM Evaluation and Translational Research, Department of Complex Prescription of TCM, China Pharmaceutical University, Nanjing, People’s Republic of China Background: Akebia saponin D (ASD exerts various pharmacological activities but with poor oral bioavailability. In this study, a self-nanoemulsifying drug delivery system (SNEDDS based on the drug–phospholipid complex technique was developed to improve the oral absorption of ASD.Methods: ASD–phospholipid complex (APC was prepared using a solvent-evaporation method and characterized by infrared spectroscopy, differential scanning calorimetry, morphology observation, and solubility test. Oil and cosurfactant were selected according to their ability to dissolve APC, while surfactant was chosen based on its emulsification efficiency in SNEDDS. Pseudoternary phase diagrams were constructed to determine the optimized APC-SNEDDS formulation, which was characterized by droplet size determination, zeta potential determination, and morphology observation. Robustness to dilution and thermodynamic stability of optimized formulation were also evaluated. Subsequently, pharmacokinetic parameters and oral bioavailability of ASD, APC, and APC-SNEDDS were investigated in rats.Results: The liposolubility significantly increased 11.4-fold after formation of APC, which was verified by the solubility test in n-octanol. Peceol (Glyceryl

  17. Preparation and evaluation of a self-nanoemulsifying drug delivery system loaded with Akebia saponin D–phospholipid complex

    Science.gov (United States)

    Shen, Jinyang; Bi, Jianping; Tian, Hongli; Jin, Ye; Wang, Yuan; Yang, Xiaolin; Yang, Zhonglin; Kou, Junping; Li, Fei

    2016-01-01

    Background Akebia saponin D (ASD) exerts various pharmacological activities but with poor oral bioavailability. In this study, a self-nanoemulsifying drug delivery system (SNEDDS) based on the drug–phospholipid complex technique was developed to improve the oral absorption of ASD. Methods ASD–phospholipid complex (APC) was prepared using a solvent-evaporation method and characterized by infrared spectroscopy, differential scanning calorimetry, morphology observation, and solubility test. Oil and cosurfactant were selected according to their ability to dissolve APC, while surfactant was chosen based on its emulsification efficiency in SNEDDS. Pseudoternary phase diagrams were constructed to determine the optimized APC-SNEDDS formulation, which was characterized by droplet size determination, zeta potential determination, and morphology observation. Robustness to dilution and thermodynamic stability of optimized formulation were also evaluated. Subsequently, pharmacokinetic parameters and oral bioavailability of ASD, APC, and APC-SNEDDS were investigated in rats. Results The liposolubility significantly increased 11.4-fold after formation of APC, which was verified by the solubility test in n-octanol. Peceol (Glyceryl monooleate [type 40]), Cremophor® EL (Polyoxyl 35 castor oil), and Transcutol HP (Diethylene glycol monoethyl ether) were selected as oil, surfactant, and cosurfactant, respectively. The optimal formulation was composed of Glyceryl monooleate (type 40), Polyoxyl 35 castor oil, Diethylene glycol monoethyl ether, and APC (1:4.5:4.5:1.74, w/w/w/w), which showed a particle size of 148.0±2.7 nm and a zeta potential of −13.7±0.92 mV after dilution with distilled water at a ratio of 1:100 (w/w) and good colloidal stability. Pharmacokinetic studies showed that APC-SNEDDS exhibited a significantly greater Cmax1 (733.4±203.8 ng/mL) than ASD (437.2±174.2 ng/mL), and a greater Cmax2 (985.8±366.6 ng/mL) than ASD (180.5±75.1 ng/mL) and APC (549.7±113

  18. Physicochemical characterization by AFM, FT-IR and DSC and biological assays of a promising antileishmania delivery system loaded with a natural Brazilian product.

    Science.gov (United States)

    Marquele-Oliveira, Franciane; Torres, Elina Cassia; Barud, Hernane da Silva; Zoccal, Karina Furlani; Faccioli, Lúcia Helena; Hori, Juliana I; Berretta, Andresa Aparecida

    2016-05-10

    The control and treatment of Leishmaniasis, a neglected and infectious disease affecting approximately 12 million people worldwide, are challenging. Leishmania parasites multiply intracellularly within macrophages located in deep skin and in visceral tissues, and the currently employed treatments for this disease are subject to significant drawbacks, such as resistance and toxicity. Thus, the search for new Leishmaniasis treatments is compulsory, and Ocotea duckei Vattimo, a plant-derived product from the biodiverse Brazilian flora, may be a promising new treatment for this disease. In this regard, the aim of this work was to develop and characterize a delivery system based on solid lipid nanoparticles (SLN) that contain the liposoluble lignan fraction (LF) of Ocotea duckei Vattimo, which targets the Leishmania phagolysosome of infected macrophages. LF-loaded SLNs were obtained via the hot microemulsion method, and their physical and chemical properties were comprehensively assessed using PCS, AFM, SEM, FT-IR, DSC, HPLC, kinetic drug release studies, and biological assays. The size of the developed delivery system was 218.85±14.2 nm, its zeta potential was -30 mV and its entrapment efficiency (EE%) was high (the EEs% of YAN [yangambin] and EPI-YAN [epi-yangambin] markers were 94.21±0.40% and 94.20±0.00%, respectively). Microscopy, FT-IR and DSC assays confirmed that the delivery system was nanosized and indicated a core-shell encapsulation model, which corroborated the measured kinetics of drug release. The total in vitro release rates of YAN and EPI-YAN in buffer (with sink conditions attained) were 29.6±8.3% and 34.3±8.9%, respectively, via diffusion through the cellulose acetate membrane of the SLN over a period of 4 h. After 24 h, the release rates of both markers reached approximately 45%, suggesting a sustained pattern of release. Mathematical modeling indicated that both markers, YAN and EPI-YAN, followed matrix diffusion-based release kinetics (Higuchi

  19. Design, formulation, in vitro, in vivo, and pharmacokinetic evaluation of nisoldipine-loaded self-nanoemulsifying drug delivery system

    Energy Technology Data Exchange (ETDEWEB)

    Krishnamoorthy, Balakumar; Habibur Rahman, S. M.; Tamil selvan, N. [PSG College of Pharmacy, Department of Pharmaceutics (India); Hari prasad, R. [PSG College of Pharmacy, Department of Pharmaceutical Analysis (India); Rajkumar, M. [PSG College of Pharmacy, Department of Pharmaceutics (India); Siva selvakumar, M. [PSG College of Pharmacy, Department of Pharmaceutical Analysis (India); Vamshikrishna, K. [PSG College of Pharmacy, Department of Pharmaceutics (India); Gregory, Marslin [University of Minho, Department of Biology (Portugal); Vijayaraghavan, Chellan, E-mail: balakumar-27@yahoo.co.uk, E-mail: drvijayaragha@gmail.com [PSG College of Pharmacy, Department of Pharmaceutics (India)

    2015-01-15

    The aim of the present work was to prepare and optimize the self-nanoemulsifying drug delivery system (SNEDDS) of poor aqueous soluble and less bioavailable nisoldipine to improve its solubility and bioavailability. The solubility of nisoldipine was assessed in various vehicles and ternary phase diagram was constructed to identify the efficient self-emulsifying region. The selected formulations were evaluated for self-emulsification time, droplet size analysis, and in vitro drug release profile. The optimized formulation ACP 19 had reduced particle size (118.3 ± 1.53 nm), when compared to PCT 08 (740 ± 1.16 nm). In vitro drug release study revealed that 98.05 ± 0.95 and 93.71 ± 1.05 % of drug was, respectively, released from ACP 19 and PCT 08 formulations at 24 h, whereas only 47.42 ± 0.65 % was released from drug in suspension. ACT 19 and PCT 08, respectively, showed 2.5- and 2.22-folds greater bioavailability than drug in suspension. PK Solver 2.0 was used for analysis of data obtained from in vivo study and the results revealed that both ACP 19 SNEDDS and drug in suspension fit into one-compartment pharmacokinetic model.

  20. The Effect of Digestion and Drug Load on Halofantrine Absorption from Self-nanoemulsifying Drug Delivery System (SNEDDS)

    DEFF Research Database (Denmark)

    Michaelsen, Maria Hotoft; Wasan, Kishor M.; Sivak, Olena

    2016-01-01

    A super-saturated self-nanoemulsifying drug delivery system (super-SNEDDS), containing the poorly water-soluble drug halofantrine (Hf) at 150% of equilibrium solubility (Seq), was compared in vitro and in vivo with a conventional SNEDDS (75% of Seq) with respect to bioavailability and digestibility....... Further, the effect of digestion on oral absorption of Hf from SNEDDS and super-SNEDDS was assessed by incorporation of the lipase inhibitor tetrahydrolipstatin (orlistat) into the SNEDDS. The SNEDDS contained soybean oil/Maisine 34-I (1:1), Kolliphor RH40, and ethanol at a ratio of 55:35:10, w/w percent....... For the dynamic in vitro lipolysis, the precipitation of Hf at 60 min was significantly larger for the super-SNEDDS (66.8 ± 16.4%) than for the SNEDDS (18.5 ± 9.2%). The inhibition of the in vitro digestion by orlistat (1% (w/w)) lowered drug precipitation significantly for both the super-SNEDDS (36.8 ± 1...

  1. Ivermectin-loaded lipid nanocapsules: toward the development of a new antiparasitic delivery system for veterinary applications.

    Science.gov (United States)

    Gamboa, G V Ullio; Palma, S D; Lifschitz, A; Ballent, M; Lanusse, C; Passirani, C; Benoit, J P; Allemandi, D A

    2016-05-01

    Ivermectin (IVM) is probably one of the most widely used antiparasitic drugs worldwide, and its efficacy is well established. However, slight differences in formulation may change the plasma kinetics, the biodistribution, and in consequence, the efficacy of this compound. The present study focuses on the development of a novel nanocarrier for the delivery of lipophilic drugs such as IVM and its potential application in antiparasitic control. Lipid nanocapsules (LNC) were prepared by a new phase inversion procedure and characterized in terms of size, surface potential, encapsulation efficiency, and physical stability. A complement activation assay (CH50) and uptake experiments by THP-1 macrophage cells were used to assess the stealth properties of this nanocarrier in vitro. Finally, a pharmacokinetics and biodistribution study was carried out as a proof of concept after subcutaneous (SC) injection in a rat model. The final IVM-LNC suspension displayed a narrow size distribution and an encapsulation rate higher than 90 % constant over the evaluated time (60 days). Through flow cytometry and blood permanence measurements, it was possible to confirm the ability of these particles to avoid the macrophage uptake. Moreover, the systemic disposition of IVM in the LNC administered by the SC route was higher (p < 0.05) (1367 ng h/ml) compared to treatment with a commercial formulation (CF) (1193 ng.h/ml), but no significant differences in the biodistribution pattern were found. In conclusion, this new carrier seems to be a promising therapeutic approach in antiparasitic control and to delay the appearance of resistance.

  2. Influence of lipid composition and drug load on the in vitro performance of self-nanoemulsifying drug delivery systems

    DEFF Research Database (Denmark)

    Thomas, Nicky; Müllertz, Anette; Graf, Anja

    2012-01-01

    size of dispersed medium-chain (MC)-SNEDDS based on the surfactant Cremophor RH40 was not affected by increasing drug loads of SIM, whereas the droplet size of the corresponding long-chain (LC)-SNEDDS increased. During 60 min in vitro lipolysis, MC-SNEDDS maintained approximately 95% of SIM in solution......, surfactant, and cosolvent but varied in the chain length of the lipid component. Utilization of the surfactant Cremophor EL resulted in pronounced changes in the droplet size of dispersed SNEDDS containing increasing drug loads of the poorly water-soluble compound simvastatin (SIM). In contrast, the droplet......, independent of the drug load. At the start of lipolysis of LC-SNEDDS, up to 34% of the drug precipitated. However, the initial precipitate dissolved in the lipolysis medium 30 min after start of in vitro lipolysis. The study suggests that drug load and lipid composition should be considered for the design...

  3. MUCOSAL DRUG DELIVERY SYSTEM

    OpenAIRE

    Madan Jyotsana; Banode Sagar; Dangi Mahesh

    2010-01-01

    The process of mucoadhesion involving a polymeric drug delivery system is a complex one that includes processes such as wetting, adsorption and interpenetration of polymer chains. The success and degree of mucoadhesion bonding is influenced by various polymer-based properties such as the degree of cross-linking, chain length and the presence of various functional groupings. The attractiveness of mucosal-targeted controlled drug delivery of active pharmaceutical ingredients, has led formulatio...

  4. Structural Features and the Anti-Inflammatory Effect of Green Tea Extract-Loaded Liquid Crystalline Systems Intended for Skin Delivery

    Directory of Open Access Journals (Sweden)

    Patricia Bento da Silva

    2017-01-01

    Full Text Available Camellia sinensis, which is obtained from green tea extract (GTE, has been widely used in therapy owing to the antioxidant, chemoprotective, and anti-inflammatory activities of its chemical components. However, GTE is an unstable compound, and may undergo reactions that lead to a reduction or loss of its effectiveness and even its degradation. Hence, an attractive approach to overcome this problem to protect the GTE is its incorporation into liquid crystalline systems (LCS that are drug delivery nanostructured systems with different rheological properties, since LCS have both fluid liquid and crystalline solid properties. Therefore, the aim of this study was to develop and characterize GTE-loaded LCS composed of polyoxypropylene (5 polyoxyethylene (20 cetyl alcohol, avocado oil, and water (F25E, F29E, and F32E with different rheological properties and to determine their anti-inflammatory efficacy. Polarized light microscopy revealed that the formulations F25, F29, and F32 showed hexagonal, cubic, and lamellar liquid crystalline mesophases, respectively. Rheological studies showed that F32 is a viscous Newtonian liquid, while F25 and F29 are dilatant and pseudoplastic non-Newtonian fluids, respectively. All GTE-loaded LCS behaved as pseudoplastic with thixotropy; furthermore, the presence of GTE increased the S values and decreased the n values, especially in F29, indicating that this LCS has the most organized structure. Mechanical and bioadhesive properties of GTE-unloaded and -loaded LCS corroborated the rheological data, showing that F29 had the highest mechanical and bioadhesive values. Finally, in vivo inflammation assay revealed that the less elastic and consistent LCS, F25E and F32E presented statistically the same anti-inflammatory activity compared to the positive control, decreasing significantly the paw edema after 4 h; whereas, the most structured and elastic LCS, F29E, strongly limited the potential effects of GTE. Thereby, the

  5. Improved corneal bioavailability of ofloxacin: biodegradable microsphere-loaded ion-activated in situ gel delivery system

    Science.gov (United States)

    Sayed, Elshaimaa G; Hussein, Amal K; Khaled, Khaled A; Ahmed, Osama AA

    2015-01-01

    The aim of the study was to improve corneal penetration and bioavailability of ofloxacin (OFX) eye preparations. OFX was incorporated in poly (lactide-co-glycolide) as biodegradable microspheres using oil in oil emulsion solvent evaporation technique. The prepared OFX microspheres were then incorporated in Gelrite® in situ gel preparation. In addition, OFX Gelrite-based in situ gel formulations were prepared. OFX formulations were characterized for gelling capacity, viscosity, and rheological properties. Release studies for OFX microspheres, OFX in situ gel, and OFX-loaded microspheres in situ gel formulations were carried out to investigate release characteristics of the drug. The prepared OFX formulations were then investigated in vivo compared with commercially available OFX eyedrops. Results showed that the optimum Gelrite concentration was at 0.4%–0.7% w/v; the prepared formulations were viscous liquid transformed into a pourable gel immediately after the addition of simulated tear fluid with a gelling factor of 27–35. Incorporation of OFX-loaded microspheres in Gelrite solution (0.4% w/v) significantly altered the release profiles of OFX-loaded microspheres in situ gel formula compared with the corresponding OFX gels and OFX microspheres. In vivo results in rabbits showed that OFX-loaded microspheres in situ gel formula improved the relative bioavailability by 11.7-fold compared with the commercially available OFX eyedrops. In addition, the longer duration of action of OFX-loaded microspheres in situ gel formula preparations is thought to avoid frequent instillations, which improves patient tolerability and compliance. PMID:25792803

  6. A pH/glutathione double responsive drug delivery system using molecular imprint technique for drug loading

    Science.gov (United States)

    Zhang, Kelin; Guan, Xiujuan; Qiu, Yanxin; Wang, Dongdong; Zhang, Xiaoyu; Zhang, Haixia

    2016-12-01

    A surface molecular imprinting polymer (SMIP) with doxorubicin (DOX) as the template was prepared on the surface of mesoporous silica nanoparticles (MSNs), which were further used as DOX carriers. The loading amount of DOX was calculated as 10.5 ± 0.2 wt% with loading efficiency of 70 ± 8%. The DOX release was controlled because the monomer molecule used in polymerization of SMIP containing sulfur-sulfur bonding, which could be decomposed with an acidic pH and glutathione (GSH). Under an acidic pH and high concentration of GSH, there was greater release of DOX than under normal physiological conditions, which induced less damage to normal cells than to cancer cells. Confocal laser scanning microscopy studies verified the invasion of the DOX within SMIP into TCA8113 cancer cells. These results indicate that the prepared SMIP was an effective nanocarrier.

  7. Ion-paired pirenzepine-loaded micelles as an ophthalmic delivery system for the treatment of myopia.

    Science.gov (United States)

    Li, Yanan; Zhang, Yong; Li, Pengmei; Mi, Gujie; Tu, Jiasheng; Sun, Linlin; Webster, Thomas J; Shen, Yan

    2017-08-01

    Myopia is one of the most common ocular disorders for which standard treatments, such as refractive surgery, often involve invasive procedures. Pirenzepine (PRZ), a muscarinic receptor antagonist, has been recognized as a promising candidate for the treatment of myopia, but possesses poor ocular bioavailability. The overall objective of this study was to prepare PRZ-sorbic acid complexes suitable to be encapsulated into micelles with high efficiency for optimal ophthalmic delivery. The results demonstrated that sorbic acid, used as the counter ion, had the most significant effects in increasing the octanol-water distribution coefficient of PRZ as well as improving its corneal permeability in vitro among various counter ions tested. In vivo absorption results showed that a 1.5 times higher bioavailability was achieved by the addition of sorbic acid at a 1:1 ratio. Cytotoxicity studies in vitro and biocompatibility studies in vivo indicated that the micelles did not cause significant toxicities to the eyes. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Thermo-sensitive liposomes loaded with doxorubicin and lysine modified single-walled carbon nanotubes as tumor-targeting drug delivery system.

    Science.gov (United States)

    Zhu, Xiali; Xie, Yingxia; Zhang, Yingjie; Huang, Heqing; Huang, Shengnan; Hou, Lin; Zhang, Huijuan; Li, Zhi; Shi, Jinjin; Zhang, Zhenzhong

    2014-11-01

    This report focuses on the thermo-sensitive liposomes loaded with doxorubicin and lysine-modified single-walled carbon nanotube drug delivery system, which was designed to enhance the anti-tumor effect and reduce the side effects of doxorubicin. Doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes was prepared by reverse-phase evaporation method, the mean particle size was 232.0 ± 5.6 nm, and drug entrapment efficiency was 86.5 ± 3.7%. The drug release test showed that doxorubicin released more quickly at 42℃ than at 37℃. Compared with free doxorubicin, doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes could efficiently cross the cell membranes and afford higher anti-tumor efficacy on the human hepatic carcinoma cell line (SMMC-7721) cells in vitro. For in vivo experiments, the relative tumor volumes of the sarcomaia 180-bearing mice in thermo-sensitive liposomes group and doxorubicin group were significantly smaller than those of N.S. group. Meanwhile, the combination of near-infrared laser irradiation at 808 nm significantly enhanced the tumor growth inhibition both on SMMC-7721 cells and the sarcomaia 180-bearing mice. The quality of life such as body weight, mental state, food and water intake of sarcomaia 180 tumor-bearing mice treated with doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes were much higher than those treated with doxorubicin. In conclusion, doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes combined with near-infrared laser irradiation at 808 nm may potentially provide viable clinical strategies for targeting delivery of anti-cancer drugs.

  9. Colloidal drug delivery systems in vaccine delivery.

    Science.gov (United States)

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

    2013-01-01

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

  10. Mucoadhesive drug delivery systems

    Directory of Open Access Journals (Sweden)

    Rahamatullah Shaikh

    2011-01-01

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

  11. MEMS: Enabled Drug Delivery Systems.

    Science.gov (United States)

    Cobo, Angelica; Sheybani, Roya; Meng, Ellis

    2015-05-01

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

  12. Energy-Aware Load Balancing in Content Delivery Networks

    CERN Document Server

    Mathew, Vimal; Shenoy, Prashant

    2011-01-01

    Internet-scale distributed systems such as content delivery networks (CDNs) operate hundreds of thousands of servers deployed in thousands of data center locations around the globe. Since the energy costs of operating such a large IT infrastructure are a significant fraction of the total operating costs, we argue for redesigning CDNs to incorporate energy optimizations as a first-order principle. We propose techniques to turn off CDN servers during periods of low load while seeking to balance three key design goals: maximize energy reduction, minimize the impact on client-perceived service availability (SLAs), and limit the frequency of on-off server transitions to reduce wear-and-tear and its impact on hardware reliability. We propose an optimal offline algorithm and an online algorithm to extract energy savings both at the level of local load balancing within a data center and global load balancing across data centers. We evaluate our algorithms using real production workload traces from a large commercial ...

  13. Folate attached, curcumin loaded Fe{sub 3}O{sub 4} nanoparticles: A novel multifunctional drug delivery system for cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Thu Huong, Le Thi [Institute of Materials Science, Ha Noi 844 (Viet Nam); Vietnam National University of Agriculture, Ha Noi 844 (Viet Nam); Nam, Nguyen Hoai, E-mail: nhnam@ims.vast.ac.vn [Institute of Materials Science, Ha Noi 844 (Viet Nam); Doan, Do Hai [Institute of Materials Science, Ha Noi 844 (Viet Nam); My Nhung, Hoang Thi [Hanoi University of Science, Vietnam National University, Ha Noi 844 (Viet Nam); Quang, Bui Thuc [National Gegiatrics Hospital, Ha Noi 844 (Viet Nam); Nam, Pham Hong; Thong, Phan Quoc; Phuc, Nguyen Xuan [Institute of Materials Science, Ha Noi 844 (Viet Nam); Thu, Ha Phuong, E-mail: thuhp@ims.vast.ac.vn [Institute of Materials Science, Ha Noi 844 (Viet Nam)

    2016-04-01

    Study and development of drug delivery nanosystem for cancer treatment are attracting great attention in recent years. In this work, we studied the role of folic acid as a targeting factor on magnetic nanoparticle Fe{sub 3}O{sub 4} based curcumin loading nanosystem. Characteristics of the nanosystems were investigated by Fourier transform infrared spectroscopy (FTIR) and field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), thermal gravimetric analysis (TGA) and vibrating sample magnetometer (VSM), while targeting role of folic was accessed in vivo on tumor bearing mice. The results showed that folate attached Fe{sub 3}O{sub 4} based curcumin loading nanosystem has very small size and exhibits better targeting effect compared to the counterpart without folate. In addition, magnetic induction heating of this nanosystem evidenced its potential for cancer hyperthermia. - Highlights: • Folate attached, curcumin loaded Fe3O4 nanoparticles were prepared and characterized. • The NPs have high curcumin loading capacity and good ability for hyperthermia. • Folate shows its bioactivity of effectively targeting the NPs to tumor tissues. • Chemotherapy, hyperthermia and targeting factor are all well combined in the NPs.

  14. Load Control System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, Daniel [Montana Tech of the Univ. of Montana, Butte, MT (United States)

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  15. Melatonin loaded ethanolic liposomes: physicochemical characterization and enhanced transdermal delivery.

    Science.gov (United States)

    Dubey, Vaibhav; Mishra, Dinesh; Jain, N K

    2007-09-01

    The current investigation aims to evaluate the transdermal potential of novel ethanolic liposomes (ethosomes) bearing Melatonin (MT), an anti-jet lag agent associated with poor skin permeation and long lag time. MT loaded ethosomes were prepared and characterized for vesicular shape and surface morphology, vesicular size, entrapment efficiency, stability, in vitro skin permeation and in vivo skin tolerability. Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and Dynamic Light Scattering (DLS) defined ethosomes as spherical, unilamellar structures having low polydispersity (0.032+/-0.011) and nanometric size range (122+/-3.5 nm). % Entrapment efficiency of MT in ethosomal carrier was found to be 70.71+/-1.4. Stability profile of prepared system assessed for 120 days revealed very low aggregation and growth in vesicular size (7.6+/-1.2%). MT loaded ethosomal carriers also provided an enhanced transdermal flux of 59.2+/-1.22 microg/cm2/h and decreased lag time of 0.9 h across human cadaver skin. Fourier Transform-Infrared (FT-IR) data generated to assess the fluidity of skin lipids after application of formulation revealed a greater mobility of skin lipids on application of ethosomes as compared to that of ethanol or plain liposomes. Skin permeation profile of the developed formulation further assessed by confocal laser scanning microscopy (CLSM) revealed an enhanced permeation of Rhodamine Red (RR) loaded formulations to the deeper layers of the skin (240 microm). Further, a better skin tolerability of ethosomal suspension on rabbit skin suggested that ethosomes may offer a suitable approach for transdermal delivery of melatonin.

  16. Dextran-based microspheres as controlled delivery systems for proteins

    NARCIS (Netherlands)

    Vlugt-Wensink, K.D.F.

    2007-01-01

    Dextran-based microspheres as controlled delivery systems for proteins Dextran based microspheres are investigated as controlled delivery system for proteins. Microspheres were prepared by polymerization of dex-HEMA in an aqueous two-phase system of dex-HEMA and PEG. Protein loaded microspheres are

  17. Preparation and Evaluation of Enteric-Coated Chitosan Derivative-Based Microparticles Loaded with Salmon Calcitonin as an Oral Delivery System

    Directory of Open Access Journals (Sweden)

    Hiraku Onishi

    2016-09-01

    Full Text Available Background: The production of protein drugs has recently increased due to advances in biotechnology, but their clinical use is generally limited to parenteral administration due to low absorption in non-parenteral administration. Therefore, non-parenteral delivery systems allowing sufficient absorption draw much attention. Methods: Microparticles (MP were prepared using chitosan-4-thio-butylamidine conjugate (Ch-TBA, trimethyl-chitosan (TMC, and chitosan (Ch. Using salmon calcitonin (sCT as a model protein drug, Ch-TBA-, Ch-TBA/TMC (4/1-, and Ch-based MP were produced, and their Eudragit L100 (Eud-coated MP, named Ch-TBA-MP/Eud, Ch-TBA/TMC-MP/Eud, and Ch-MP/Eud, respectively, were prepared as oral delivery systems. These enteric-coated microparticles were examined in vitro and in vivo. Results: All microparticles before and after enteric coating had a submicron size (600–800 nm and micrometer size (1300–1500 nm, respectively. In vitro release patterns were similar among all microparticles; release occurred gradually, and the release rate was slower at pH 1.2 than at pH 6.8. In oral ingestion, Ch-TBA-MP/Eud suppressed plasma Ca levels most effectively among the microparticles tested. The relative effectiveness of Ch-TBA-MP/Eud to the intramuscular injection was 8.6%, while the sCT solution showed no effectiveness. Conclusion: The results suggest that Eud-coated Ch-TBA-based microparticles should have potential as an oral delivery system of protein drugs.

  18. RECENT ADVANCES IN NOVEL DRUG DELIVERY SYSTEMS

    Directory of Open Access Journals (Sweden)

    Manivannan Rangasamy

    2010-12-01

    Full Text Available Drug delivered can have significant effect on its efficacy. Some drugs have an optimum concentration range with in which maximum benefit is derived and concentrations above (or below the range can be toxic or produce no therapeutic effect. Various drug delivery and drug targeting systems are currently under development. The main goal for developing such delivery systems is to minimize drug degradation and loss, to prevent harmful side effects and to increase bioavailability. Targeting is the ability to direct the drug loaded system to the site of interest. Among drug carrier one can name soluble polymers, microparticles made of insoluble (or biodegradable natural and synthetic polymers, microcapsules, cells, cell ghosts, lipoproteins, liposomes and micelles. Two major mechanisms can be distinguished for addressing the desired sites for drug release, (a Passive and (b Active targeting. Controlled drug carrier systems such as micellar solutions, vescicles and liquid crystal dispersions, as well as nanoparticle dispersions consisting of small particles of 10 – 400 nm show great promise as drug delivery systems. Hydrogels are three dimensional, hydrophilic, polymer networks capable of imbibing large amounts of water or biological fluids. Buckyballs, a novel delivery system with 60 carbon atoms formed in the shape of hollow ball. They are other type’s namely bucky babies, fuzzy balls, gadofullereness, and giant fullerenes. Nanoparticles can be classified as nano tubes, nano wires, nano cantilever, nanoshells, quantum dots, nano pores. Researchers at north western university using gold particles to develop ultra sensitive detection systems for DNA and protein markers associated with many forms of cancer, including breast and prostrate cancer. Drug loaded erythrocytes is one of the growing and potential systems for delivery of drugs and enzymes.

  19. Transcutaneous antigen delivery system

    Directory of Open Access Journals (Sweden)

    Mi-Young Lee

    2013-01-01

    Full Text Available Transcutaneous immunization refers to the topical applicationof antigens onto the epidermis. Transcutaneous immunizationtargeting the Langerhans cells of the skin has received muchattention due to its safe, needle-free, and noninvasive antigendelivery. The skin has important immunological functions withunique roles for antigen-presenting cells such as epidermalLangerhans cells and dermal dendritic cells. In recent years,novel vaccine delivery strategies have continually beendeveloped; however, transcutaneous immunization has not yetbeen fully exploited due to the penetration barrier representedby the stratum corneum, which inhibits the transport ofantigens and adjuvants. Herein we review recent achievementsin transcutaneous immunization, focusing on the variousstrategies for the enhancement of antigen delivery andvaccination efficacy. [BMB Reports 2013; 46(1: 17-24

  20. Starch Applications for Delivery Systems

    Science.gov (United States)

    Li, Jason

    2013-03-01

    Starch is one of the most abundant and economical renewable biopolymers in nature. Starch molecules are high molecular weight polymers of D-glucose linked by α-(1,4) and α-(1,6) glycosidic bonds, forming linear (amylose) and branched (amylopectin) structures. Octenyl succinic anhydride modified starches (OSA-starch) are designed by carefully choosing a proper starch source, path and degree of modification. This enables emulsion and micro-encapsulation delivery systems for oil based flavors, micronutrients, fragrance, and pharmaceutical actives. A large percentage of flavors are encapsulated by spray drying in today's industry due to its high throughput. However, spray drying encapsulation faces constant challenges with retention of volatile compounds, oxidation of sensitive compound, and manufacturing yield. Specialty OSA-starches were developed suitable for the complex dynamics in spray drying and to provide high encapsulation efficiency and high microcapsule quality. The OSA starch surface activity, low viscosity and film forming capability contribute to high volatile retention and low active oxidation. OSA starches exhibit superior performance, especially in high solids and high oil load encapsulations compared with other hydrocolloids. The submission is based on research and development of Ingredion

  1. Novel central nervous system drug delivery systems.

    Science.gov (United States)

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

    2014-05-01

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

  2. Optimizing Consulting Delivery Systems.

    Science.gov (United States)

    Spottswood, Curran

    1980-01-01

    Summarizes a study of several types of consulting groups in the Bell System and describes characteristics which are associated with high-impact consulting. A strategy which is designed for internal consulting organizations to maximize the likelihood of both initial success and long-term survival of the group is proposed. (Author/MER)

  3. Software Build and Delivery Systems

    Energy Technology Data Exchange (ETDEWEB)

    Robey, Robert W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-07-10

    This presentation deals with the hierarchy of software build and delivery systems. One of the goals is to maximize the success rate of new users and developers when first trying your software. First impressions are important. Early successes are important. This also reduces critical documentation costs. This is a presentation focused on computer science and goes into detail about code documentation.

  4. Intranasal Delivery of Camptothecin-Loaded Tat-Modified Nanomicells for Treatment of Intracranial Brain Tumors

    Directory of Open Access Journals (Sweden)

    Yuuki Takashima

    2012-10-01

    Full Text Available The blood-brain barrier is a substantial obstacle for delivering anticancer agents to brain tumors, and new strategies for bypassing it are sorely needed for brain tumor therapy. Intranasal delivery provides a practical, noninvasive method for delivering therapeutic agents to the brain. Intranasal application of nano-sized micelles that have been modified with Tat peptide facilitates brain delivery of fluorescent model materials. In this study, we evaluated a nose-to-brain delivery system for brain tumor therapy. We nasally administered the anti-tumor drug camptothecin (CPT in solution and in methoxy poly(ethylene glycol (MPEG/poly(e-caprolactone (PCL amphiphilic block copolymers (MPEG-PCL and cell penetrating peptide, Tat analog-modified MPEG-PCL (MPEG-PCL-Tat MPEG-PCL-Tat to rats bearing intracranial glioma tumors and quantified the cytotoxicity against glioma cells, and the therapeutic effects. CPT-loaded MPEG-PCL-Tat micelles showed higher cytotoxicity than CPT-loaded MPEG-PCL. CPT-free MPEG-PCL-Tat didn’t show any cytotoxicity, even at high concentrations (2 mmol/mL. CPT-loaded MPEG-PCL-Tat micelles significantly prolonged the median survival of rats. These results indicate that intranasal delivery of anti-cancer drugs with cell penetrating peptide-modified nanomicelles might be an effective therapy for brain tumors.

  5. Sterile Product Packaging and Delivery Systems.

    Science.gov (United States)

    Akers, Michael J

    2015-01-01

    Both conventional and more advanced product container and delivery systems are the focus of this brief article. Six different product container systems will be discussed, plus advances in primary packaging for special delivery systems and needle technology.

  6. Drug loading, dispersion stability, and therapeutic efficacy in targeted drug delivery with carbon nanotubes

    OpenAIRE

    Heister, E; Neves, V.; Lamprecht, C.; Silva, SRP; Coley, HM; Mcfadden, J.

    2012-01-01

    We have designed a drug delivery system for the anti-cancer drugs doxorubicin and mitoxantrone based on carbon nanotubes, which is stable under biological conditions, allows for sustained release, and promotes selectivity through an active targeting scheme. Carbon nanotubes are particularly promising for this area of application due to their high surface area, allowing for high drug loading, and their unique interaction with cellular membranes. We have taken a systematic approach to PEG conju...

  7. Nasal mucoadhesive delivery systems of the anti-parkinsonian drug, apomorphine: influence of drug-loading on in vitro and in vivo release in rabbits.

    Science.gov (United States)

    Ikechukwu Ugwoke, M; Sam, E; Van Den Mooter, G; Verbeke, N; Kinget, R

    1999-04-20

    Lyophilized polyacrylic acid powder formulations loaded with apomorphine HCl were prepared and the influence of drug loading on in vitro release and in vivo absorption studied after intranasal administration in rabbits. These formulations prepared with Carbopol 971P, Carbopol 974P and polycarbophil sustained apomorphine release both in vitro and in vivo. The in vitro release rate and mechanism were both influenced by the drug loading. There was no large influence of drug loading on the time to achieve the peak (Tmax) for a particular polymer, but Tmax differed between different polymers. For a particular drug loading, the Tmax from Carbopol 971P was the slowest compared with that for Carbopol 974P and polycarbophil; however, only the Tmax from Carbopol 971P loaded with 15% w/w of apomorphine was significantly longer than polycarbophil of similar drug loading (P=0.0386). The trend further observed was that increasing drug loading led to increased peak plasma concentration and area under the curve (AUC). In the second part of this study, a mixture containing an immediate release component and sustained release formulation was administered in an attempt to increase the initial plasma level, as this could be therapeutically beneficial. Only one peak plasma concentration was observed and the initial plasma concentrations were no higher than those obtained with solely sustained release formulation. The Tmax, the peak plasma drug concentration (Cmax) and AUC from the lactose-containing formulation were lower than the formulation without lactose but the differences were only marginally statistically significant for Cmax (P=0.0911) and AUC (P=0.0668), but not Tmax (P=0.2788).

  8. Loading of Drug-Polymer Matrices in Microreservoirs for Oral Drug Delivery

    DEFF Research Database (Denmark)

    Petersen, Ritika Singh; Keller, Stephan Sylvest; Boisen, Anja

    2016-01-01

    For major advances in microfabricated drug delivery systems (DDS), fabrication methods with high throughput using biocompatible polymers are required. Once these DDS are fabricated, loading of drug poses a significant challenge. Here, hot punching is presented as an innovative method for drug...... loading in microfabricated DDS. The microfabricated DDS are microcontainers fabricated in photoresist SU-8 and biopolymer poly-L-lactic-acid (PLLA). Furosemide (F) drug is embedded in poly-ε-caprolactone (PCL) polymer matrix. This F-PCL drug polymer matrix is loaded in SU-8 and PLLA microcontainers using...... hot punching with >99% yield. Thus, it is illustrated that hot punching allows high-throughput, parallel loading of 3D polymer microcontainers with drug-polymer matrices in a single process step....

  9. Phytochemical-loaded mesoporous silica nanoparticles for nose-to-brain olfactory drug delivery.

    Science.gov (United States)

    Lungare, Shital; Hallam, Keith; Badhan, Raj K S

    2016-11-20

    Central nervous system (CNS) drug delivery is often hampered due to the insidious nature of the blood-brain barrier (BBB). Nose-to-brain delivery via olfactory pathways have become a target of attention for drug delivery due to bypassing of the BBB. The antioxidant properties of phytochemicals make them promising as CNS active agents but possess poor water solubility and limited BBB penetration. The primary aim of this study was the development of mesoporous silica nanoparticles (MSNs) loaded with the poorly water-soluble phytochemicals curcumin and chrysin which could be utilised for nose-to-brain delivery. We formulated spherical MSNP using a templating approach resulting in ∼220nm particles with a high surface porosity. Curcumin and chrysin were successfully loaded into MSNP and confirmed through Fourier transformation infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and HPLC approaches with a loading of 11-14% for curcumin and chrysin. Release was pH dependant with curcumin demonstrating increased chemical stability at a lower pH (5.5) with a release of 53.2%±2.2% over 24h and 9.4±0.6% for chrysin. MSNP were demonstrated to be non-toxic to olfactory neuroblastoma cells OBGF400, with chrysin (100μM) demonstrating a decrease in cell viability to 58.2±8.5% and curcumin an IC50 of 33±0.18μM. Furthermore confocal microscopy demonstrated nanoparticles of <500nm were able to accumulate within cells with FITC-loaded MSNP showing membrane localised and cytoplasmic accumulation following a 2h incubation. MSNP are useful carriers for poorly soluble phytochemicals and provide a novel vehicle to target and deliver drugs into the CNS and bypass the BBB through olfactory drug delivery.

  10. Design and evaluation of an intravesical delivery system for superficial bladder cancer: preparation of gemcitabine HCl-loaded chitosan-thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers.

    Science.gov (United States)

    Şenyiğit, Zeynep Ay; Karavana, Sinem Yaprak; İlem-Özdemir, Derya; Çalışkan, Çağrı; Waldner, Claudia; Şen, Sait; Bernkop-Schnürch, Andreas; Baloğlu, Esra

    2015-01-01

    This study aimed to develop an intravesical delivery system of gemcitabine HCl for superficial bladder cancer in order to provide a controlled release profile, to prolong the residence time, and to avoid drug elimination via urination. For this aim, bioadhesive nanoparticles were prepared with thiolated chitosan (chitosan-thioglycolic acid conjugate) and were dispersed in bioadhesive chitosan gel or in an in situ gelling poloxamer formulation in order to improve intravesical residence time. In addition, nanoparticle-loaded gels were diluted with artificial urine to mimic in vivo conditions in the bladder and were characterized regarding changes in gel structure. The obtained results showed that chitosanthioglycolic acid nanoparticles with a mean diameter of 174.5±3.762 nm and zeta potential of 32.100±0.575 mV were successfully developed via ionotropic gelation and that the encapsulation efficiency of gemcitabine HCl was nearly 20%. In vitro/ex vivo characterization studies demonstrated that both nanoparticles and nanoparticle-loaded chitosan and poloxamer gels might be alternative carriers for intravesical administration of gemcitabine HCl, prolonging its residence time in the bladder and hence improving treatment efficacy. However, when the gel formulations were diluted with artificial urine, poloxamer gels lost their in situ gelling properties at body temperature, which is in conflict with the aimed formulation property. Therefore, 2% chitosan gel formulation was found to be a more promising carrier system for intravesical administration of nanoparticles.

  11. Organic nanotubes for drug loading and cellular delivery.

    Science.gov (United States)

    Wakasugi, Ai; Asakawa, Masumi; Kogiso, Masaki; Shimizu, Toshimi; Sato, Mamiko; Maitani, Yoshie

    2011-07-15

    Organic nanotubes made of synthetic amphiphilic molecules are novel materials that form by self-assembly. In this study, organic nanotubes with a carboxyl group (ONTs) at the surface were used as a carrier for the anticancer drug doxorubicin, which has a weak amine group. The IC(50) values of ONT for cells were higher than that of conventional liposomes, suggesting that ONTs are safe. The results showed that the drug loading of ONTs was susceptible to the effect of ionic strength and H(+) concentration in the medium, and drug release from ONTs was promoted at lower pH, which is favorable for the release of drugs in the endosome after cellular uptake. ONTs loaded with the drug were internalized, and the drug was released quickly in the cells, as demonstrated on transmission electron microscopy images of ONTs and the detection of a 0.05% dose of ONT chelating gadolinium in the cells. Moreover, ONT could be modified chemically with folate by simply mixing with a folate-conjugate lipid. Therefore, these novel, biodegradable organic nanotubes have the potential to be used as drug carriers for controlled and targeting drug delivery.

  12. Synthesis and Characterization of Poly(lactic-co-glycolic Acid Nanoparticles-Loaded Chitosan/Bioactive Glass Scaffolds as a Localized Delivery System in the Bone Defects

    Directory of Open Access Journals (Sweden)

    K. Nazemi

    2014-01-01

    Full Text Available The functionality of tissue engineering scaffolds can be enhanced by localized delivery of appropriate biological macromolecules incorporated within biodegradable nanoparticles. In this research, chitosan/58S-bioactive glass (58S-BG containing poly(lactic-co-glycolic acid (PLGA nanoparticles has been prepared and then characterized. The effects of further addition of 58S-BG on the structure of scaffolds have been investigated to optimize the characteristics of the scaffolds for bone tissue engineering applications. The results showed that the scaffolds had high porosity with open pores. It was also shown that the porosity decreased with increasing 58S-BG content. Furthermore, the PLGA nanoparticles were homogenously distributed within the scaffolds. According to the obtained results, the nanocomposites could be considered as highly bioactive bone tissue engineering scaffolds with the potential of localized delivery of biological macromolecules.

  13. Evaluation of Drug Load and Polymer by Using a 96-Well Plate Vacuum Dry System for Amorphous Solid Dispersion Drug Delivery

    OpenAIRE

    Chiang, Po-Chang; Ran, Yingqing; Chou, Kang-Jye; Cui, Yong; Sambrone, Amy; Chan, Connie; Hart, Ryan

    2012-01-01

    It is well recognized that poor dissolution rate and solubility of drug candidates are key limiting factors for oral bioavailability. While numerous technologies have been developed to enhance solubility of the drug candidates, poor water solubility continuously remains a challenge for drug delivery. Among those technologies, amorphous solid dispersions (SD) have been successfully employed to enhance both dissolution rate and solubility of poorly water-soluble drugs. This research reports a h...

  14. Electronic Nicotine Delivery Systems Key Facts Infographic

    Data.gov (United States)

    U.S. Department of Health & Human Services — Explore the Electronic Nicotine Delivery Systems Key Facts Infographic which outlines key facts related to electronic nicotine delivery systems (ENDS), including...

  15. Preparing and evaluating delivery systems for proteins

    DEFF Research Database (Denmark)

    Jorgensen, L; Moeller, E H; van de Weert, M

    2006-01-01

    From a formulation perspective proteins are complex and therefore challenging molecules to develop drug delivery systems for. The success of a formulation depends on the ability of the protein to maintain the native structure and activity during preparation and delivery as well as during shipping...... and long-term storage of the formulation. Therefore, the development and evaluation of successful and promising drug delivery systems is essential. In the present review, some of the particulate drug delivery systems for parenteral delivery of protein are presented and discussed. The challenge...... for incorporation of protein in particulate delivery systems is exemplified by water-in-oil emulsions....

  16. Preparation and In Vitro Release of Drug-Loaded Microparticles for Oral Delivery Using Wholegrain Sorghum Kafirin Protein

    Directory of Open Access Journals (Sweden)

    Esther T. L. Lau

    2015-01-01

    Full Text Available Kafirin microparticles have been proposed as an oral nutraceutical and drug delivery system. This study investigates microparticles formed with kafirin extracted from white and raw versus cooked red sorghum grains as an oral delivery system. Targeted delivery to the colon would be beneficial for medication such as prednisolone, which is used in the management of inflammatory bowel disease. Therefore, prednisolone was loaded into microparticles of kafirin from the different sources using phase separation. Differences were observed in the protein content, in vitro protein digestibility, and protein electrophoretic profile of the various sources of sorghum grains, kafirin extracts, and kafirin microparticles. For all of the formulations, the majority of the loaded prednisolone was not released in in vitro conditions simulating the upper gastrointestinal tract, indicating that most of the encapsulated drug could reach the target area of the lower gastrointestinal tract. This suggests that these kafirin microparticles may have potential as a colon-targeted nutraceutical and drug delivery system.

  17. Methylprednisolone acetate-loaded hydroxyapatite nanoparticles as a potential drug delivery system for treatment of rheumatoid arthritis: In vitro and in vivo evaluations.

    Science.gov (United States)

    Jafari, Samira; Maleki-Dizaji, Nasrin; Barar, Jaleh; Barzegar-Jalali, Mohammad; Rameshrad, Maryam; Adibkia, Khosro

    2016-08-25

    The objective of this study was to improve the therapeutic efficacy of methylprednisolone acetate (MPA) in the treatment of rheumatoid arthritis (RA) by incorporating the drug into the hydroxyapatite (HAp) nanoparticles. The nanoparticles were synthesized using a chemical precipitation technique and their size and morphology were evaluated by dynamic light scattering and scanning electron microscopy (SEM). The solid-state behavior of the nanoparticles was also characterized by operating X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). The Brunauer-Emmett-Teller and Barrett-Joyner-Halenda N2 adsorption/desorption analyses were also performed to determine the surface area, Vm (the volume of the N2 adsorbed on the one gram of the HAp when the monolayer is complete) and the pore size of the samples. Furthermore, the therapeutic efficacy of the prepared nanoformulation on the adjuvant induced arthritic rats was assessed. HAp mesoporous nanoparticles with a particle size of 70.45nm, pore size of 2.71nm and drug loading of 44.53% were obtained. The specific surface area of HAp as well as the Vm values were decreased after the drug loading process. The nanoformulation revealed the slower drug release profile compared to the pure drug. The MTT assay indicated that the MPA-loaded nanoparticles had a lower cytotoxic effect on NIH-3T3 and CAOV-4 cell lines compared to the pure drug. Interestingly, the in vivo study confirmed that the drug-loaded nanoparticles could considerably decrease the paw volume and normalize the hematological abnormalities in the arthritic rats.

  18. Dual drug-loaded nanoparticles on self-integrated scaffold for controlled delivery

    Directory of Open Access Journals (Sweden)

    Bennet D

    2012-07-01

    Full Text Available Devasier Bennet,1 Mohana Marimuthu,1 Sanghyo Kim,1 Jeongho An21Department of Bionanotechnology, Gachon University, Gyeonggi, Republic of Korea; 2Department of Polymer Science and Engineering, SunKyunKwan University, Gyeonggi, Republic of KoreaAbstract: Antioxidant (quercetin and hypoglycemic (voglibose drug-loaded poly-D,L-lactide-co-glycolide nanoparticles were successfully synthesized using the solvent evaporation method. The dual drug-loaded nanoparticles were incorporated into a scaffold film using a solvent casting method, creating a controlled transdermal drug-delivery system. Key features of the film formulation were achieved utilizing several ratios of excipients, including polyvinyl alcohol, polyethylene glycol, hyaluronic acid, xylitol, and alginate. The scaffold film showed superior encapsulation capability and swelling properties, with various potential applications, eg, the treatment of diabetes-associated complications. Structural and light scattering characterization confirmed a spherical shape and a mean particle size distribution of 41.3 nm for nanoparticles in the scaffold film. Spectroscopy revealed a stable polymer structure before and after encapsulation. The thermoresponsive swelling properties of the film were evaluated according to temperature and pH. Scaffold films incorporating dual drug-loaded nanoparticles showed remarkably high thermoresponsivity, cell compatibility, and ex vivo drug-release behavior. In addition, the hybrid film formulation showed enhanced cell adhesion and proliferation. These dual drug-loaded nanoparticles incorporated into a scaffold film may be promising for development into a transdermal drug-delivery system.Keywords: quercetin, voglibose, biocompatible materials, encapsulation, transdermal

  19. Vaginal delivery of carboplatin-loaded thermosensitive hydrogel to prevent local cervical cancer recurrence in mice.

    Science.gov (United States)

    Wang, Xue; Wang, Jin; Wu, Wenbin; Li, Hongjun

    2016-11-01

    Local tumor recurrence after cervical cancer surgery remains a clinical problem. Vaginal delivery of thermosensitive hydrogel may be suited to reduce tumor relapse rate with more efficacy and safety. A pilot study was carried out to evaluate the efficacy of carboplatin-loaded poloxamer hydrogel to prevent local recurrence of cervical cancer after surgery. In vivo vaginal retention evaluation of 27% poloxamer hydrogel in mice was proven to be a suitable vaginal drug delivery formulation due to its low gelation temperature. A mimic orthotopic cervical/vaginal cancer recurrence model after surgery was established by injecting murine cervical cancer cell line U14 into the vaginal submucosa to simulate the residual tumor cells infiltrated in the surgical site, followed by drug administration 24 h later to interfere with the formation/recurrence of the tumor. By infusing fluorescein sodium-loaded hydrogel into the vagina of mice, a maximized accumulation of fluorescein sodium (Flu) in the vagina was achieved and few signals were observed in other organs. When used in the prevention of the cervical cancer formation/recurrence in mice, the carboplatin-loaded poloxamer hydrogel exhibited great efficacy and systemic safety. In conclusion, thermosensitive hydrogel presents a simple, practical approach for the local drug delivery via vagina against cervical cancer recurrence.

  20. Anti-cancer vaccination by transdermal delivery of antigen peptide-loaded nanogels via iontophoresis.

    Science.gov (United States)

    Toyoda, Mao; Hama, Susumu; Ikeda, Yutaka; Nagasaki, Yukio; Kogure, Kentaro

    2015-04-10

    Transdermal vaccination with cancer antigens is expected to become a useful anti-cancer therapy. However, it is difficult to accumulate enough antigen in the epidermis for effective exposure to Langerhans cells because of diffusion into the skin and muscle. Carriers, such as liposomes and nanoparticles, may be useful for the prevention of antigen diffusion. Iontophoresis, via application of a small electric current, is a noninvasive and efficient technology for transdermal drug delivery. Previously, we succeeded in the iontophoretic transdermal delivery of liposomes encapsulating insulin, and accumulation of polymer-based nanoparticle nanogels in the stratum corneum of the skin. Therefore, in the present study, we examined the use of iontophoresis with cancer antigen gp-100 peptide KVPRNQDWL-loaded nanogels for anti-cancer vaccination. Iontophoresis resulted in the accumulation of gp-100 peptide and nanogels in the epidermis, and subsequent increase in the number of Langerhans cells in the epidermis. Moreover, tumor growth was significantly suppressed by iontophoresis of the antigen peptide-loaded nanogels. Thus, iontophoresis of the antigen peptide-loaded nanogels may serve as an effective transdermal delivery system for anti-cancer vaccination.

  1. Preparation and evaluation of quercetin-loaded lecithin-chitosan nanoparticles for topical delivery

    Science.gov (United States)

    Tan, Qi; Liu, Weidong; Guo, Chenyu; Zhai, Guangxi

    2011-01-01

    Background The purpose of this study was to investigate lecithin-chitosan nanoparticles as a topical delivery system for quercetin. Methods Tocopheryl propylene glycol succinate was chosen to be the surfactant for the nanosystem. The mean particle size of the nanoparticles was 95.3 nm, and the entrapment efficiency and drug loading for quercetin were 48.5% and 2.45%, respectively. Topical delivery in vitro and in vivo of the quercetin-loaded nanoparticles was evaluated using quercetin propylene glycol solution as the control. Results Compared with quercetin solution, the quercetin-loaded nanoparticles showed higher permeation ability, and significantly increased accumulation of quercetin in the skin, especially in the epidermis. Microstructure observation of the skin surface after administration indicated that the interaction between ingredients of the nanoparticles and the skin surface markedly changed the morphology of the stratum corneum and disrupted the corneocyte layers, thus facilitating the permeation and accumulation of quercetin in skin. Conclusion Lecithin-chitosan nanoparticles are a promising carrier for topical delivery of quercetin. PMID:21904452

  2. A REVIEW ON OSMOTIC DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Harnish Patel

    2012-04-01

    Full Text Available Conventional oral drug delivery systems supply an instantaneous release of drug, which cannot control the release of the drug and effective concentration at the target site. This kind of dosing pattern may result in constantly changing, unpredictable plasma concentrations. Drugs can be delivered in a controlled pattern over a long period of time by the process of osmosis. Osmotic devices are the most promising strategy based systems for controlled drug delivery. They are the most reliable controlled drug delivery systems and could be employed as oral drug delivery systems. Various patents available for osmotic drug delivery system like Rose-Nelson pump, Higuchi leeper pump, Higuchi Theeuwes pump, Elementary Osmotic pump etc. ODDS are useful for poorly soluble drug, for pulsatile drug release, zero order release. Various techniques available for preparation of ODDS include push pull osmotic Pump, osmotic Brusting osmotic pump, liquid oral osmotic system, sandwiched osmotic tablets , delayed delivery osmotic device, monolithic osmotic System and controlled porosity osmotic Pump. Osmotically controlled oral drug delivery systems utilize osmotic pressure for controlled delivery of active agents. These systems can be utilized for systemic as well as targeted delivery of drugs. The release of drugs from osmotic systems is governed by various formulation factors such as solubility and osmotic pressure of the core components, size of the delivery orifice, and nature of the rate-controlling membrane. In this Paper mainly focused on the Osmotic System with example, the basic component of osmotic system and evaluation parameter of the osmotic drug delivery system.

  3. Polymer-filled microcontainers for oral delivery loaded using supercritical impregnation

    DEFF Research Database (Denmark)

    Marizza, Paolo; Keller, Stephan Sylvest; Müllertz, Anette

    2014-01-01

    In the last years a large variety of drug delivery systems have been developed to improve bioavailability of therapeutics in oral administration. An increasing interest has arisen in reservoir-based microdevices designed for active ingredients like water insoluble compounds and fragile biomolecules...... procedures. This work proposes an effective loading technique for a poorly soluble model drug in microcontainers, by combining inkjet printing and supercritical fluid impregnation. Well defined quantities of poly(vinyl pyrrolidone) (PVP) solutions are dispensed into microcontainers by inkjet printing...... with a quasi-no-waste performance. Then ketoprofen is impregnated in the polymer matrix by using supercritical carbon dioxide (scCO2) as loading medium. The amount of polymer is controlled by the volume and the number of droplets of dispensed polymer and drug loading is tuned by varying the impregnation...

  4. Enhanced transdermal delivery of indomethacin-loaded PLGA nanoparticles by iontophoresis.

    Science.gov (United States)

    Tomoda, Keishiro; Terashima, Hiroto; Suzuki, Kenichi; Inagi, Toshio; Terada, Hiroshi; Makino, Kimiko

    2011-12-01

    Nanoparticles effectively deliver therapeutic agent by penetrating into the skin. Indomethacin (IM) and coumarin-6 were loaded in PLGA nanoparticles with an average diameter of 100 nm. IM and coumarin-6 were chosen as a model drug and as a fluorescent marker, respectively. The surfaces of the nanoparticles were negatively charged. Permeability of IM-loaded PLGA nanoparticles through rat skin was studied. Higher amount of IM was delivered through skin when IM was loaded in nanoparticles than IM was free molecules. Also, iontophoresis was applied to enhance the permeability of nanoparticles. When iontophoresis with 3 V/cm was applied, permeability of IM was much higher than that obtained by simple diffusion of nanoparticles through skin. The combination of charged nanoparticle system with iontophoresis is useful for effective transdermal delivery of therapeutic agents.

  5. Resveratrol-loaded nanoparticles conjugated with kidney injury molecule-1 as a drug delivery system for potential use in chronic kidney disease.

    Science.gov (United States)

    Lin, Yuh-Feng; Lee, Yu-Hsuan; Hsu, Yung-Ho; Chen, Yi-Jie; Lin, Yuan-Feng; Cheng, Fong-Yu; Chiu, Hui-Wen

    2017-09-08

    We used resveratrol (Res)-loaded nanoparticles (Res NPs) as a novel method for improving the pharmacokinetic properties of Res and analyzed the effect of Res NPs in chronic kidney disease (CKD). We coupled anti-kidney injury molecule-1 antibodies to Res NPs and analyzed safety and efficacy. Res NPs had low toxicity and induced autophagy. Res NPs inhibited the NLRP3 inflammasome and IL-1β secretion. Higher NLRP3 expression levels were observed in peripheral blood monocytic cells of CKD patients than healthy individuals. Treatment with kidney injury molecule-1-Res NPs significantly reduced creatinine and protected against tubulointerstitial injury in a murine model of CKD. Res NPs through NLRP3 inflammasome attenuation and autophagy induction may be as a strategy to prevent CKD.

  6. UNIQUE ORAL DRUG DELIVERY SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Raphael M. Ottenbrite; ZHAO Ruifeng; Sam Milstein

    1995-01-01

    An oral drug delivery system using proteinoid microspheres is discussed with respect to its unique dependence on pH. It has been found that certain drugs such as insulin and heparin can be encapsulated in proteinoid spheres at stomach pH's (1-3). These spheres also dissemble at intestinal pH's (6-7) releasing the drug for absorption. Using this technique low molecular weight heparin and human growth hormone have been orally delivered successfully to several animal species. Future work has been proposed to study the interaction and binding of the specific drugs with synthesized oligopeptides.

  7. TRANSDERMAL DRUG DELIVERY SYSTEM: REVIEW

    Directory of Open Access Journals (Sweden)

    Virendra Yadav

    2012-01-01

    Full Text Available Transdermal drug delivery system (TDDS are topically administered medicaments in the form of patches that deliver drugs for systemic effects at a predetermined and controlled rate. It works very simply in which drug is applied inside the patch and it is worn on skin for long period of time. By this constant concentration of drug remain in blood for long time. Polymer matrix, drug, permeation enhancers are the main components of TDDS; polymers includes Zein, Shellac (as a natural to synthetic ones (Polybutadiene, Polysiloxane, Polyvinyl chloride, Polyvinyl alcohol etc.. TDDS are of many types varying from single layer drug in adhesive to multi layer drug in adhesive and others are reservoir and the matrix systems. The market value of TDDS products are increasing with rapid rate, more than 35 products have now been approved for sale in US, and approximately 16 active ingredients are approved globally for use as a TDDS. Transdermal drug delivery is a recent technology which promises a great future it has a potential to limit the use of needles for administering wide variety of drugs but cost factor is a important thing to consider since developing nations like INDIA have second highest population, but due to higher cost TDDS are the hidden part of therapy used in general population.

  8. Gantries and dose delivery systems

    Science.gov (United States)

    Meer, David; Psoroulas, Serena

    2015-06-01

    Particle therapy is a field in remarkable development, with the goal of increasing the number of indications which could benefit from such treatments and the access to the therapy. The therapeutic usage of a particle beam defines the technical requirements of all the elements of the therapy chain: we summarize the main characteristics of accelerators, the beam line, the treatment room, the integrated therapy and imaging systems used in particle therapy. Aiming at a higher flexibility in the choice of treatments, an increasing number of centers around the world have chosen to equip their treatment rooms with gantries, rotating beam line structures that allow a complete flexibility in the choice of the treatment angle. We review the current designs. A particle therapy gantry though is a quite expensive structure, and future development will increasingly consider reducing the cost and the footprint. Increasing the number of indications also means development in the delivery techniques and solving some of the issues which traditionally affected particle therapy, for example the precision of the delivery in presence of motion and the large penumbras for low depths. We show the current strategies in these fields, focusing on pencil beam scanning (PBS), and give some hints about future developments.

  9. Ocular Drug Delivery through pHEMA-Hydrogel Contact Lenses Co-Loaded with Lipophilic Vitamins

    Science.gov (United States)

    Lee, Dasom; Cho, Seungkwon; Park, Hwa Sung; Kwon, Inchan

    2016-01-01

    Ocular drug delivery through hydrogel contact lenses has great potential for the treatment of ocular diseases. Previous studies showed that the loading of lipophilic vitamin E to silicone-hydrogel contact lenses was beneficial in ocular drug delivery. We hypothesized that vitamin E loading to another type of popular hydrogel contact lenses, pHEMA-hydrogel contact lenses, improves ocular drug delivery by increasing the drug loading or the duration of drug release. Loading of vitamin E to pHEMA-hydrogel contact lenses significantly increased the loading of a hydrophilic drug surrogate (Alexa Fluor 488 dye) and two hydrophilic glaucoma drugs (timolol and brimonidine) to the lenses by 37.5%, 19.1%, and 18.7%, respectively. However, the release duration time was not significantly altered. Next, we hypothesized that the lipophilic nature of vitamin E attributes to the enhanced drug loading. Therefore, we investigated the effects of co-loading of another lipophilic vitamin, vitamin A, on drug surrogate delivery. We found out that vitamin A loading also increased the loading of the drug surrogate to pHEMA-hydrogel contact lenses by 30.3%. Similar to vitamin E loading, vitamin A loading did not significantly alter the release duration time of the drug or drug surrogate. PMID:27678247

  10. Ocular Drug Delivery through pHEMA-Hydrogel Contact Lenses Co-Loaded with Lipophilic Vitamins

    Science.gov (United States)

    Lee, Dasom; Cho, Seungkwon; Park, Hwa Sung; Kwon, Inchan

    2016-09-01

    Ocular drug delivery through hydrogel contact lenses has great potential for the treatment of ocular diseases. Previous studies showed that the loading of lipophilic vitamin E to silicone-hydrogel contact lenses was beneficial in ocular drug delivery. We hypothesized that vitamin E loading to another type of popular hydrogel contact lenses, pHEMA-hydrogel contact lenses, improves ocular drug delivery by increasing the drug loading or the duration of drug release. Loading of vitamin E to pHEMA-hydrogel contact lenses significantly increased the loading of a hydrophilic drug surrogate (Alexa Fluor 488 dye) and two hydrophilic glaucoma drugs (timolol and brimonidine) to the lenses by 37.5%, 19.1%, and 18.7%, respectively. However, the release duration time was not significantly altered. Next, we hypothesized that the lipophilic nature of vitamin E attributes to the enhanced drug loading. Therefore, we investigated the effects of co-loading of another lipophilic vitamin, vitamin A, on drug surrogate delivery. We found out that vitamin A loading also increased the loading of the drug surrogate to pHEMA-hydrogel contact lenses by 30.3%. Similar to vitamin E loading, vitamin A loading did not significantly alter the release duration time of the drug or drug surrogate.

  11. Ultrasound assisted siRNA delivery using PEG-siPlex loaded microbubbles.

    Science.gov (United States)

    Vandenbroucke, Roosmarijn E; Lentacker, Ine; Demeester, Joseph; De Smedt, Stefaan C; Sanders, Niek N

    2008-03-20

    Short interfering RNA (siRNA) attracts much attention for the treatment of various diseases. However, its delivery, especially via systemic routes, remains a challenge. Indeed, naked siRNAs are rapidly degraded, while complexed siRNAs massively aggregate in the blood or are captured by macrophages. Although this can be circumvented by PEGylation, we found that PEGylation had a strong negative effect on the gene silencing efficiency of siRNA-liposome complexes (siPlexes). Recently, ultrasound combined with microbubbles has been used to deliver naked siRNA but the gene silencing efficiency is rather low and very high amounts of siRNA are required. To overcome the negative effects of PEGylation and to enhance the efficiency of ultrasound assisted siRNA delivery, we coupled PEGylated siPlexes (PEG-siPlexes) to microbubbles. Ultrasound radiation of these microbubbles resulted in massive release of unaltered PEG-siPlexes. Interestingly, PEG-siPlexes loaded on microbubbles were able to enter cells after exposure to ultrasound, in contrast to free PEG-siPlexes, which were not able to enter cells rapidly. Furthermore, these PEG-siPlex loaded microbubbles induced, in the presence of ultrasound, much higher gene silencing than free PEG-siPlexes. Additionally, the PEG-siPlex loaded microbubbles only silenced the expression of genes in the presence of ultrasound, which allows space and time controlled gene silencing.

  12. Integrated delivery systems. Evolving oligopolies.

    Science.gov (United States)

    Malone, T A

    1998-01-01

    The proliferation of Integrated Delivery Systems (IDSs) in regional health care markets has resulted in the movement of these markets from a monopolistic competitive model of behavior to an oligopoly. An oligopoly is synonymous with competition among the few, as a small number of firms supply a dominant share of an industry's total output. The basic characteristics of a market with competition among the few are: (1) A mutual interdependence among the actions and behaviors of competing firms; (2) competition tends to rely on the differentiation of products; (3) significant barriers to entering the market exist; (4) the demand curve for services may be kinked; and (5) firms can benefit from economies of scale. An understanding of these characteristics is essential to the survival of IDSs as regional managed care markets mature.

  13. Cell Delivery System for Traumatic Brain Injury

    Science.gov (United States)

    2008-03-21

    REPORT Cell Delivery System for Traumatic Brain Injury 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: We have met all of the milestones outlined in this...COVERED (From - To) 18-Sep-2006 Standard Form 298 (Rev 8/98) Prescribed by ANSI Std. Z39.18 - 17-Mar-2008 Cell Delivery System for Traumatic Brain Injury Report...Manassero*, Justin Kim*, Maureen St Georges*, Nicole Esclamado* and Elizabeth Orwin. “Development of a Cell Delivery System for Traumatic Brain Injury Using

  14. Cell Based Drug Delivery: Micrococcus luteus Loaded Neutrophils as Chlorhexidine Delivery Vehicles in a Mouse Model of Liver Abscesses in Cattle.

    Directory of Open Access Journals (Sweden)

    Sebastian O Wendel

    Full Text Available The recent WHO report on antibiotic resistances shows a dramatic increase of microbial resistance against antibiotics. With only a few new antibiotics in the pipeline, a different drug delivery approach is urgently needed. We have obtained evidence demonstrating the effectiveness of a cell based drug delivery system that utilizes the innate immune system as targeting carrier for antibacterial drugs. In this study we show the efficient loading of neutrophil granulocytes with chlorhexidine and the complete killing of E. coli as well as Fusobacterium necrophorum in in-vitro studies. Fusobacterium necrophorum causes hepatic abscesses in cattle fed high grain diets. We also show in a mouse model that this delivery system targets infections of F. necrophorum in the liver and reduces the bacterial burden by an order of magnitude from approximately 2•106 to 1•105.

  15. Cell Based Drug Delivery: Micrococcus luteus Loaded Neutrophils as Chlorhexidine Delivery Vehicles in a Mouse Model of Liver Abscesses in Cattle.

    Science.gov (United States)

    Wendel, Sebastian O; Menon, Sailesh; Alshetaiwi, Hamad; Shrestha, Tej B; Chlebanowski, Lauren; Hsu, Wei-Wen; Bossmann, Stefan H; Narayanan, Sanjeev; Troyer, Deryl L

    2015-01-01

    The recent WHO report on antibiotic resistances shows a dramatic increase of microbial resistance against antibiotics. With only a few new antibiotics in the pipeline, a different drug delivery approach is urgently needed. We have obtained evidence demonstrating the effectiveness of a cell based drug delivery system that utilizes the innate immune system as targeting carrier for antibacterial drugs. In this study we show the efficient loading of neutrophil granulocytes with chlorhexidine and the complete killing of E. coli as well as Fusobacterium necrophorum in in-vitro studies. Fusobacterium necrophorum causes hepatic abscesses in cattle fed high grain diets. We also show in a mouse model that this delivery system targets infections of F. necrophorum in the liver and reduces the bacterial burden by an order of magnitude from approximately 2•106 to 1•105.

  16. Buparvaquone loaded solid lipid nanoparticles for targeted delivery in theleriosis

    Directory of Open Access Journals (Sweden)

    Maheshkumar P Soni

    2014-01-01

    Full Text Available Background: Buparvaquone (BPQ, a hydroxynaphthoquinone derivative, has been investigated for the treatment of many infections and is recommended as the gold standard for the treatment of theileriosis. Theileriosis, an intramacrophage infection is localized mainly in reticuloendotheileial system (RES organs. The present study investigates development of solid lipid nanoparticles (SLN of BPQ for targeted delivery to the RES. Materials and Methods: BPQ SLN was prepared using melt method by adding a molten mixture into aqueous Lutrol F68 solution (80°C. Larger batches were prepared up to 6 g of BPQ with GMS: BPQ, 2:1. SLN of designed size were obtained using ultraturrax and high pressure homogenizer. A freeze and thaw study was used to optimize type and concentration of cryoprotectant with Sf: Mean particle size, Si: Initial particle size <1.3. Differential scanning calorimetry (DSC, powder X-ray diffraction (XRD and scanning electron microscope (SEM study was performed on optimized formulation. Formulation was investigated for in vitro serum stability, hemolysis and cell uptake study. Pharmacokinetic and biodistribution study was performed in Holtzman rat. Results: Based on solubility in lipid; glyceryl monostearate (GMS was selected for preparation of BPQ SLN. Batches of BPQ SLN were optimized for average particle size and entrapment efficiency at <100 mg solid content. A combination of Solutol HS-15 and Lutrol F68 at 2% w/v and greater enabled the desired Sf/Si < 1.3. Differential scanning calorimetry and powder X-ray diffraction revealed decrease in crystallinity of BPQ in BPQ SLN while, scanning electron microscope revealed spherical morphology. BPQ SLN revealed good stability at 4°C and 25°C. Low hemolytic potential (<8% and in vitro serum stability up to 5 h was observed. Cytotoxicity of SLN to the U937 cell was low. The macrophage cell line revealed high (52% uptake of BPQ SLN in 1 h suggesting the potential to RES uptake. SLN revealed

  17. Design and evaluation of an intravesical delivery system for superficial bladder cancer: preparation of gemcitabine HCl-loaded chitosan–thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers

    Directory of Open Access Journals (Sweden)

    Ay Şenyiğit Z

    2015-10-01

    Full Text Available Zeynep Ay Şenyiğit,1 Sinem Yaprak Karavana,1 Derya İlem-Özdemir,2 Çağrı Çalışkan,2 Claudia Waldner,3 Sait Şen,4 Andreas Bernkop-Schnürch,5 Esra Baloğlu1 1Faculty of Pharmacy, Department of Pharmaceutical Technology, Ege University, Bornova, İzmir, Turkey; 2Faculty of Pharmacy, Department of Radiopharmacy, Ege University, Bornova, İzmir, Turkey; 3ThioMatrix, Forschungs-Beratungs GmbH, Innsbruck, Austria; 4Faculty of Medicine, Department of Pathology, Ege University, Bornova, İzmir, Turkey; 5Institute of Pharmacy, Department of Pharmaceutical Technology, University of Innsbruck, Innsbruck, AustriaAbstract: This study aimed to develop an intravesical delivery system of gemcitabine HCl for superficial bladder cancer in order to provide a controlled release profile, to prolong the residence time, and to avoid drug elimination via urination. For this aim, bioadhesive nanoparticles were prepared with thiolated chitosan (chitosan–thioglycolic acid conjugate and were dispersed in bioadhesive chitosan gel or in an in situ gelling poloxamer formulation in order to improve intravesical residence time. In addition, nanoparticle-loaded gels were diluted with artificial urine to mimic in vivo conditions in the bladder and were characterized regarding changes in gel structure. The obtained results showed that chitosan-thioglycolic acid nanoparticles with a mean diameter of 174.5±3.762 nm and zeta potential of 32.100±0.575 mV were successfully developed via ionotropic gelation and that the encapsulation efficiency of gemcitabine HCl was nearly 20%. In vitro/ex vivo characterization studies demonstrated that both nanoparticles and nanoparticle-loaded chitosan and poloxamer gels might be alternative carriers for intravesical administration of gemcitabine HCl, prolonging its residence time in the bladder and hence improving treatment efficacy. However, when the gel formulations were diluted with artificial urine, poloxamer gels lost their in

  18. Automated Loads Analysis System (ATLAS)

    Science.gov (United States)

    Gardner, Stephen; Frere, Scot; O’Reilly, Patrick

    2013-01-01

    ATLAS is a generalized solution that can be used for launch vehicles. ATLAS is used to produce modal transient analysis and quasi-static analysis results (i.e., accelerations, displacements, and forces) for the payload math models on a specific Shuttle Transport System (STS) flight using the shuttle math model and associated forcing functions. This innovation solves the problem of coupling of payload math models into a shuttle math model. It performs a transient loads analysis simulating liftoff, landing, and all flight events between liftoff and landing. ATLAS utilizes efficient and numerically stable algorithms available in MSC/NASTRAN.

  19. Organoclays for drug delivery Systems

    OpenAIRE

    Canovas Creus, Alba

    2008-01-01

    Modified clays can be used as carriers of drugs due to their suitable properties and structure in order to achieve improvements in drug delivery. The study of this thesis starts with an introduction to mineral clays and its classification, properties and characterization, then deepens into modified clays (properties, comparison with mineral clays, applications and procedure of modification). Another chapter is focused in drug delivery: definition, its difficulties nowadays and the different w...

  20. Amsacrine analog-loaded solid lipid nanoparticle to resolve insolubility for injection delivery: characterization and pharmacokinetics

    Directory of Open Access Journals (Sweden)

    Fang YP

    2016-03-01

    Full Text Available Yi-Ping Fang,1 Chih-Hung Chuang,2 Pao-Chu Wu,1 Yaw-Bin Huang,1 Cherng-Chyi Tzeng,3 Yeh-Long Chen,3 Ya-Ting Liu,1 Yi-Hung Tsai,1 Ming-Jun Tsai4–6 1School of Pharmacy, College of Pharmacy, 2Department of Biomedical and Environment Biology, College of Life Science, 3School of Medicinal and Applied Chemistry, College of Life Science, Kaohsiung Medical University, Kaohsiung, 4Department of Neurology, China Medical University Hospital, 5School of Medicine, Medical College, China Medical University, Taichung, 6Department of Neurology, China Medical University An-Nan Hospital, Tainan, Taiwan Abstract: Amsacrine analog is a novel chemotherapeutic agent that provides potentially broad antitumor activity when compared to traditional amsacrine. However, the major limitation of amsacrine analog is that it is highly lipophilic, making it nonconductive to intravenous administration. The aim of this study was to utilize solid lipid nanoparticles (SLN to resolve the delivery problem and to investigate the biodistribution of amsacrine analog-loaded SLN. Physicochemical characterizations of SLN, including particle size, zeta potential, entrapment efficiency, and stability, were evaluated. In vitro release behavior was also measured by the dialysis method. In vivo pharmacokinetics and biodistribution behavior of amsacrine analog were investigated and incorporated with a non invasion in vivo imaging system to confirm the localization of SLN. The results showed that amsacrine analog-loaded SLN was 36.7 nm in particle size, 0.37 in polydispersity index, and 34.5±0.047 mV in zeta potential. More than 99% of amsacrine analog was successfully entrapped in the SLN. There were no significant differences in the physicochemical properties after storage at room temperature (25°C for 1 month. Amsacrine analog-loaded SLN maintained good stability. An in vitro release study showed that amsacrine analog-loaded SLN sustained a release pattern and followed the zero equation. An

  1. Doxorubicin loaded PVA coated iron oxide nanoparticles for targeted drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Kayal, S. [School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Ramanujan, R.V., E-mail: ramanujan@ntu.edu.sg [School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore)

    2010-04-06

    Magnetic drug targeting is a drug delivery system that can be used in locoregional cancer treatment. Coated magnetic particles, called carriers, are very useful for delivering chemotherapeutic drugs. Magnetic carriers were synthesized by coprecipitation of iron oxide followed by coating with polyvinyl alcohol (PVA). Characterization was carried out using X-ray diffraction, TEM, TGA, FTIR and VSM techniques. The magnetic core of the carriers was magnetite (Fe{sub 3}O{sub 4}), with average size of 10 nm. The room temperature VSM measurements showed that magnetic particles were superparamagnetic. The amount of PVA bound to the iron oxide nanoparticles were estimated by thermogravimetric analysis (TGA) and the attachment of PVA to the iron oxide nanoparticles was confirmed by FTIR analysis. Doxorubicin (DOX) drug loading and release profiles of PVA coated iron oxide nanoparticles showed that up to 45% of adsorbed drug was released in 80 h, the drug release followed the Fickian diffusion-controlled process. The binding of DOX to the PVA was confirmed by FTIR analysis. The present findings show that DOX loaded PVA coated iron oxide nanoparticles are promising for magnetically targeted drug delivery.

  2. Spray-freeze-dried dry powder inhalation of insulin-loaded liposomes for enhanced pulmonary delivery.

    Science.gov (United States)

    Bi, Ru; Shao, Wei; Wang, Qun; Zhang, Na

    2008-11-01

    Nowadays, growing attention has been paid to the pulmonary region as a target for the delivery of peptide and protein drugs, especially macromolecules with systemic effect like insulin, since the pulmonary route exhibits numerous benefits to be an alternative for repeated injection. Furthermore, encapsulation of insulin into liposomal carriers is an attractive way to increase drug retention time and control the drug release in the lung; however, its long-term stability during storage in the reservoir and the process of aerosolization might be suspected when practically applied. Thus, the aim of this study was to design and characterize dry powder inhalation of insulin-loaded liposomes prepared by novel spray-freeze-drying method for enhanced pulmonary delivery. Process variables such as compressed air pressure, pump speed, and concentration were optimized for parameters such as mean particle diameter, moisture content, and fine particle fraction of the produced powders. Influence of different kinds and amounts of lyoprotectants was also evaluated for the best preservation of the drug entrapped in the liposome bilayers after the dehydration-rehydration cycle. The in vivo study of intratracheal instillation of insulin-loaded liposomes to diabetic rats showed successful hypoglycemic effect with low blood glucose level and long-lasting period and a relative pharmacological bioavailability as high as 38.38% in the group of 8 IU/kg dosage.

  3. Engineering the system of healthcare delivery

    National Research Council Canada - National Science Library

    Rouse, William B; Cortese, Denis A

    2010-01-01

    "As the United States continues to debate reform of its healthcare system, this book argues that providing health insurance for all without improving the delivery system will not improve the current...

  4. Polymer hydrogels as optimized delivery systems

    Energy Technology Data Exchange (ETDEWEB)

    Batista, Jorge G.S.; Varca, Gustavo H.C.; Ferraz, Caroline C.; Garrido, Gabriela P.; Diniz, Bruna M.; Carvalho, Vinicius S.; Lugao, Ademar B., E-mail: jorgegabriel@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Hydrogels are formed by polymers capable of absorbing large quantities of water. They consist of one or more three-dimensionally structured polymer networks formed by macromolecular chains linked by covalent bonds-crosslinks - and physical interactions. The application of hydrogels, has been widely studied. Biodegradable synthetic or natural polymers such as chitosan, starch and poly-lactic-co-glycolic acid, have properties that allow the development of biodegradable systems for drug and nutraceutics delivery. This study aimed to develop polymeric hydrogels based on polyvinyl alcohol, polyacrylamide and polyvinylpyrrolidone using ionizing radiation in order to develop hydrogels for improved loading and release of compounds. Polymer solutions were solubilized in water and poured into thermoformed packages. After sealing, the material was subjected to γ-irradiation at 25kGy. The samples were assayed by means of mechanical properties, gel fraction and swelling degree. Nanostructure characterization was performed using Flory's equation to determine crosslinking density. The systems developed showed swelling degree and adequate mechanical resistance. The nanostructure evaluation showed different results for each system demonstrating the need of choosing the polymer based on the specific properties of each material. (author)

  5. Long-term stability, biocompatibility and oral delivery potential of risperidone-loaded solid lipid nanoparticles.

    Science.gov (United States)

    Silva, A C; Kumar, A; Wild, W; Ferreira, D; Santos, D; Forbes, B

    2012-10-15

    A solid lipid nanoparticles (SLN) formulation to improve the oral delivery of risperidone (RISP), a poorly water-soluble drug, was designed and tested. Initially, lipid-RISP solubility was screened to select the best lipid for SLN preparation. Compritol(®)-based formulations were chosen and their long-term stability was assessed over two years of storage (at 25 °C and 4 °C) by means of particle size, polydispersity index (PI), zeta potential (ZP) and encapsulation efficiency (EE) measurements. SLN shape was observed by transmission electron microscopy (TEM) at the beginning and end of the study. The oxidative potential (OP) of the SLN was measured and their biocompatibility with Caco-2 cells was evaluated using the (4,5-dimethylthiazol-2-yl)2,5-dyphenyl-tetrazolium bromide (MTT) assay. In vitro drug release and transport studies were performed to predict the in vivo release profile and to evaluate the drug delivery potential of the SLN formulations, respectively. The RISP-loaded SLN systems were stable and had high EE and similar shape to the placebo formulations before and after storage. Classical Fickian diffusion was identified as the release mechanism for RISP from the SLN formulation. Biocompatibility and dose-dependent RISP transport across Caco-2 cells were observed for the prepared SLN formulations. The viability of SLN as formulations for oral delivery of poorly water-soluble drugs such as RISP was illustrated.

  6. MULTIPARTICULATE DRUG DELIVERY SYSTEM: PELLETIZATION THROUGH EXTRUSION AND SPHERONIZATION

    Directory of Open Access Journals (Sweden)

    Anshuli Sharma

    2013-02-01

    Full Text Available Pharmaceutical invention and research are increasingly focusing on delivery systems which enhance desirable therapeutic objectives while minimising side effects. Recent trends indicate that multiparticulate drug delivery systems are especially suitable for achieving controlled or delayed release oral formulations with low risk of dose dumping, flexibility of blending to attain different release patterns as well as reproducible and short gastric residence time. Pelletization is a technique used to prepare fine powders into pellets used as multiparticulate drug delivery systems. There are different pelletization techniques used to prepare pellets. Extrusion and spheronization is one of them used to prepare pellets drug loaded beads/pellets for extended release or sustained release oral formulations such as tablets and capsules.

  7. Engineered nanoscaled polyplex gene delivery systems.

    Science.gov (United States)

    Fernandez, Christian A; Rice, Kevin G

    2009-01-01

    Improving the transfection efficiencies of nonviral gene delivery requires properly engineered nanoscaled delivery carriers that can overcome the multiple barriers associated with the delivery of oligonucleotides from the site of administration to the nucleus or cytoplasm of the target cell. This article reviews the current advantages and limitation of polyplex nonviral delivery systems, including the apparent barriers that limit gene expression efficiency compared to physical methods such as hydrodynamic dosing and electroporation. An emphasis is placed on engineered nanoscaled polyplexes (NSPs) of modular design that both self-assemble and systematically disassemble at the desired stage of delivery. It is suggested that NSPs of increasingly sophisticated designs are necessary to improve the efficiency of the rate limiting steps in gene delivery.

  8. New Delivery Systems and Propellants

    Directory of Open Access Journals (Sweden)

    Myrna Dolovich

    1999-01-01

    Full Text Available The removal of chlorofluorocarbon (CFC propellants from industrial and household products has been agreed to by over 165 countires of which more than 135 are developing countries. The timetable for this process is outlined in the Montreal Protocol on Substances that Deplete the Ozone Layer document and in several subsequent amendments. Pressured metered dose inhalers (pMDIs for medical use have been granted temporary exemptions until replacement formulations, providing the same medication via the same route, and with the same efficacy and safety profiles, are approved for human use. Hydrofluoroalkanes (HFAs are the alternative propellants for CFCs-12 and -114. Their potential for damage to the ozone layer is nonexistent, and while they are greenhouse gases, their global warming potential is a fraction (one-tenth of that of CFCs. Replacement formulations for almost all inhalant respiratory medications have been or are being produced and tested; in Canada, it is anticipated that the transition to these HFA or CFC-free pMDIs will be complete by the year 2005. Initially, an HFA pMDI was to be equivalent to the CFC pMDI being replaced, in terms of aerosol properties and effective clinical dose. However, this will not necessarily be the situation, particularly for some corticosteroid products. Currently, only one CFC-free formulation is available in Canada – Airomir, a HFA salbutamol pMDI. This paper discusses the in vitro aerosol characteristics, in vivo deposition and clinical data for several HFA pMDIs for which there are data available in the literature. Alternative delivery systems to the pMDI, namely, dry powder inhalers and nebulizers, are briefly reviewed.

  9. Fiber laser coupled optical spark delivery system

    Science.gov (United States)

    Yalin, Azer [Fort Collins, CO; Willson, Bryan [Fort Collins, CO; Defoort, Morgan [Fort Collins, CO; Joshi, Sachin [Fort Collins, CO; Reynolds, Adam [Fort Collins, CO

    2008-03-04

    A spark delivery system for generating a spark using a laser beam is provided, and includes a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. The laser delivery assembly further includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. Other embodiments use a fiber laser to generate a spark. Embodiments of the present invention may be used to create a spark in an engine. Yet other embodiments include collecting light from the spark or a flame resulting from the spark and conveying the light for diagnostics. Methods of using the spark delivery systems and diagnostic systems are provided.

  10. Multi-channel gas-delivery system

    Energy Technology Data Exchange (ETDEWEB)

    Rozenzon, Yan; Trujillo, Robert T.; Beese, Steven C.

    2016-09-13

    One embodiment of the present invention provides a gas-delivery system for delivering reaction gas to a reactor chamber. The gas-delivery system includes a main gas-inlet port for receiving reaction gases and a gas-delivery plate that includes a plurality of gas channels. A gas channel includes a plurality of gas holes for allowing the reaction gases to enter the reactor chamber from the gas channel. The gas-delivery system further includes a plurality of sub-gas lines coupling together the main gas-inlet port and the gas-delivery plate, and a respective sub-gas line is configured to deliver a portion of the received reaction gases to a corresponding gas channel.

  11. Lipid Based Vesicular Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Shikha Jain

    2014-01-01

    Full Text Available Vesicular drug delivery system can be defined as highly ordered assemblies consisting of one or more concentric bilayers formed as a result of self-assembling of amphiphilic building blocks in presence of water. Vesicular drug delivery systems are particularly important for targeted delivery of drugs because of their ability to localize the activity of drug at the site or organ of action thereby lowering its concentration at the other sites in body. Vesicular drug delivery system sustains drug action at a predetermined rate, relatively constant (zero order kinetics, efficient drug level in the body, and simultaneously minimizes the undesirable side effects. It can also localize drug action in the diseased tissue or organ by targeted drug delivery using carriers or chemical derivatization. Different types of pharmaceutical carriers such as polymeric micelles, particulate systems, and macro- and micromolecules are presented in the form of novel drug delivery system for targeted delivery of drugs. Particulate type carrier also known as colloidal carrier system, includes lipid particles, micro- and nanoparticles, micro- and nanospheres, polymeric micelles and vesicular systems like liposomes, sphingosomes, niosomes, transfersomes, aquasomes, ufasomes, and so forth.

  12. 姜黄素自微乳化制剂制备及其稳定性研究%Study on Preparation and Stability of Curcumin-loaded Self-microemulsifying Drug Delivery System

    Institute of Scientific and Technical Information of China (English)

    蓝苑元; 罗恋; 吕亚丽; 马萍; 刘丽宏

    2012-01-01

    目的:研究姜黄素自微乳化制剂(SMEDDS)的处方最佳组成和比例;考察SMEDDS对姜黄素稳定性的影响.方法:用溶解性试验、初步筛选试验和伪三相图法进行姜黄素SMEDDS制备研究,通过评价自微乳化效果和乳滴粒径大小,绘制出姜黄素SMEDDS的成乳区域,优选处方的最佳组成和比例;采用HPLC-UV检测比较姜黄素提取物及其SMEDDS中姜黄素的含量变化.结果:姜黄素SMEDDS处方组成为中碳链甘三酯、聚氧乙烯蓖麻油、丙三醇时,能获得较好的自微乳化效果;光照、50℃和100℃加热各6h,以及酸性条件下姜黄素及其SMEDDS稳定性良好.但pH >7时,姜黄素迅速分解,其SMEDDS稳定.结论:姜黄素SMEDDS的处方比例为碳链甘三酯4.2 g、聚氧乙烯蓖麻油1.8 g、丙三醇4.0g时,姜黄素载量为200 mg,制得的姜黄素SMEDDS乳化效果良好,且在弱碱性条件下其稳定性大大提高.%Objective; To investigate the optimum formula of curcumin-loaded self-microemulsifying drug delivery system (SMEDDS) and evaluate the stability of curcumin. Method; Solubility test, screening test and a pseudo-ternary phase diagram were used to study the preparation of curcumin-loaded SMEDDS. The region and optimum formula of the SMEDDS were determined by the self-emulsifying degree and the particle size. The stability of curcumin in SMEDDS was evaluated based on the HPLC analysis. Result; The formula of the curcumin SMEDDS was composed of Crodamol GTCC as the oil phase, Cremophor EL as the nonionic surfactant and glycerol as the co-surfactant, which could obtain the best emulsifying effect. Curcumin was stable under the conditions of strong light, 50℃ and 100℃ as well as pH value S≤7. In alkaline solution, curcumin was decomposed quickly, however curcumin in the SMEDDS was still stable. Conclusion; The proportion of Crodamol GTCC of 4.2 g, Cremophor EL of 1. 8 g and glycerol of 4.0 g exists in the region of SMEDDS which could form a

  13. Interactive mixture as a rapid drug delivery system.

    Science.gov (United States)

    Lee, Chin Chiat; Ong, Charlene Li Ching; Heng, Paul Wan Sia; Chan, Lai Wah; Wong, Tin Wui

    2008-02-01

    The effectiveness of an interactive mixture as a rapid drug delivery system is compared with that of a solid dispersion. The influences of drug load, particle size, and crystallinity of these test systems are investigated. The interactive mixtures and solid dispersions were prepared from polyethylene glycol (PEG) 3350 and hydrophobic nifedipine drug by means of physical mixing and melting methods, respectively. The formed products were subjected to drug particle size and crystallinity analyses, and dissolution tests. In comparison with the interactive mixtures, the solid dispersions with low drug load were more effective as a rapid drug delivery system, as the size of a given batch of drug particles was markedly reduced by the molten PEG 3350. The rate and extent of drug dissolution were mainly promoted by decreasing effective drug particle size. However, these were lower in the solid dispersions than in the interactive mixtures when a high load of fine drug particles was used as the starting material. This was attributed to drug coarsening during the preparation of the solid dispersion. Unlike solid dispersions, the interactive mixtures could accommodate a high load of fine drug particles without compromising its capacity to enhance the rate and extent of drug dissolution. The interactive mixture is appropriate for use to deliver a fine hydrophobic drug in a formulation requiring a high drug load.

  14. Cellular delivery of enzyme-loaded DNA origami.

    Science.gov (United States)

    Ora, Ari; Järvihaavisto, Erika; Zhang, Hongbo; Auvinen, Henni; Santos, Hélder A; Kostiainen, Mauri A; Linko, Veikko

    2016-12-01

    In this communication, we show that active enzymes can be delivered into HEK293 cells in vitro when they are attached to tubular DNA origami nanostructures. We use bioluminescent enzymes as a cargo and monitor their activity from a cell lysate. The results show that the enzymes stay intact and retain their activity in the transfection process. The method is highly modular, which makes it a compelling candidate for a great variety of delivery applications.

  15. Nanoengineered drug delivery systems for enhancing antibiotic therapy.

    Science.gov (United States)

    Kalhapure, Rahul S; Suleman, Nadia; Mocktar, Chunderika; Seedat, Nasreen; Govender, Thirumala

    2015-03-01

    Formulation scientists are recognizing nanoengineered drug delivery systems as an effective strategy to overcome limitations associated with antibiotic drug therapy. Antibiotics encapsulated into nanodelivery systems will contribute to improved management of patients with various infectious diseases and to overcoming the serious global burden of antibiotic resistance. An extensive review of several antibiotic-loaded nanocarriers that have been formulated to target drugs to infectious sites, achieve controlled drug release profiles, and address formulation challenges, such as low-drug entrapment efficiencies, poor solubility and stability is presented in this paper. The physicochemical properties and the in vitro/in vivo performances of various antibiotic-loaded delivery systems, such as polymeric nanoparticles, micelles, dendrimers, liposomes, solid lipid nanoparticles, lipid-polymer hybrid nanoparticles, nanohybirds, nanofibers/scaffolds, nanosheets, nanoplexes, and nanotubes/horn/rods and nanoemulsions, are highlighted and evaluated. Future studies that will be essential to optimize formulation and commercialization of these antibiotic-loaded nanosystems are also identified. The review presented emphasizes the significant formulation progress achieved and potential that novel nanoengineered antibiotic drug delivery systems have for enhancing the treatment of patients with a range of infections.

  16. Wind loads on solar energy systems

    NARCIS (Netherlands)

    Kampen, B.J.M. van; Geurts, C.P.W.; Borsboom, W.A.; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads 0on solar energy systems,. which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The

  17. Wind loads on solar energy systems

    NARCIS (Netherlands)

    Kampen, B.J.M. van; Geurts, C.P.W.; Borsboom, W.A.; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads 0on solar energy systems,. which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The re

  18. Wind loads on solar energy systems

    NARCIS (Netherlands)

    Kampen, B.J.M. van; Geurts, C.P.W.; Borsboom, W.A.; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads 0on solar energy systems,. which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The re

  19. Drug delivery systems from nose to brain.

    Science.gov (United States)

    Misra, Ambikanandan; Kher, Gitanjali

    2012-09-01

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

  20. Radiation sterilization of new drug delivery systems.

    Science.gov (United States)

    Abuhanoğlu, Gürhan; Ozer, A Yekta

    2014-06-01

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

  1. One-step fabrication of agent-loaded biodegradable microspheroids for drug delivery and imaging applications.

    Science.gov (United States)

    Heslinga, Michael J; Willis, Gabriella M; Sobczynski, Daniel J; Thompson, Alex J; Eniola-Adefeso, Omolola

    2014-04-01

    Non-spherical particles may offer advantages over conventional spherical systems for drug delivery applications. This work describes the fabrication of agent-loaded poly(lactic-co-glycolic acid) (PLGA) spheroids via the emulsion solvent evaporation (ESE) method. The versatility of this technique for loading a variety of therapeutics is demonstrated via loading of paclitaxel, bovine serum albumin, and cadmium sulfide nanoparticles into PLGA spheroids. The encapsulation efficiency for spheroids fabricated via oil-in-water (O/W) emulsions is highest at low aqueous phase surfactant concentrations while the encapsulation efficiency for spheroids made via water-in-oil-in-water (W/O/W) is highest at high aqueous phase surfactant concentrations and basic aqueous phase pH values. Particle aspect ratio polydispersity can be minimized via the use of high aqueous phase PVA concentration and pH. The ESE technique is an attractive alternative to recently described methods for fabrication of non-spherical particles due to its simplicity in setup, high particle yield and adaptability to a variety of biodegradable polymers and therapeutics. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Hydrogen storage and delivery system development

    Energy Technology Data Exchange (ETDEWEB)

    Handrock, J.L.; Wally, K.; Raber, T.N. [Sandia National Labs., Livermore, CA (United States)

    1995-09-01

    Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. The purpose of this project is to develop a platform for the engineering evaluation of hydrogen storage and delivery systems with an added focus on lightweight hydride utilization. Hybrid vehicles represent the primary application area of interest, with secondary interests including such items as existing vehicles and stationary uses. The near term goal is the demonstration of an internal combustion engine/storage/delivery subsystem. The long term goal is optimization of storage technologies for both vehicular and industrial stationary uses. In this project an integrated approach is being used to couple system operating characteristics to hardware development. A model has been developed which integrates engine and storage material characteristics into the design of hydride storage and delivery systems. By specifying engine operating parameters, as well as a variety of storage/delivery design features, hydride bed sizing calculations are completed. The model allows engineering trade-off studies to be completed on various hydride material/delivery system configurations. A more generalized model is also being developed to allow the performance characteristics of various hydrogen storage and delivery systems to be compared (liquid, activated carbon, etc.). Many of the features of the hydride storage model are applicable to the development of this more generalized model.

  3. Characterisation of zinc delivery from a nipple shield delivery system using a breastfeeding simulation apparatus

    National Research Council Canada - National Science Library

    Scheuerle, Rebekah L; Bruggraber, Sylvaine F. A; Gerrard, Stephen E; Kendall, Richard A; Tuleu, Catherine; Slater, Nigel K. H

    2017-01-01

      Zinc delivery from a nipple shield delivery system (NSDS), a novel platform for administering medicines to infants during breastfeeding, was characterised using a breastfeeding simulation apparatus...

  4. Microneedles: an emerging transdermal drug delivery system.

    Science.gov (United States)

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

    2012-01-01

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

  5. Microemulsion Drug Delivery Systems for Radiopharmacy Studies

    Directory of Open Access Journals (Sweden)

    Emre Ozgenc

    2016-11-01

    Full Text Available Microemulsions have been used increasingly for last year’s because of ideal properties like favorable drug delivery, ease of preparation and physical stability. They have been improved the solubility and efficacy of the drug and reduce the side effects. Use of radiolabeled microemulsions plays an alternative role in drug delivery systems by investigating the formation, stability and application of microemulsions in radiopharmacy. Gama scintigraphic method is well recognized for developing and detecting the biodistribution of newly developed drugs or formulation. This review will focus on how radionuclides are able to play role with characterization studies of microemulsion drug delivery systems.

  6. Rivastigmine-loaded in situ gelling nanostructured lipid carriers for nose to brain delivery.

    Science.gov (United States)

    Wavikar, Preeti R; Vavia, Pradeep R

    2015-01-01

    In the current research work, rivastigmine (RV)-loaded in situ gelling nanostructured lipid carriers (NLCs) were developed for nose to brain delivery. NLCs were fabricated by ethanol injection method using glyceryl monosterate, Capmul MCM C8, Lecithin and Tween 80. NLCs showed average particle size of 123.2 ± 2.3 nm with entrapment efficiency of 68.34 ± 3.4%. DSC, XRD and IR studies showed complete amorphization and incorporation of the drug into nanoparticles. NLCs were incorporated into an in situ gelling system using 0.8% gellan gum and 15% Lutrol F 127. RV in situ gel showed excellent elasticity, rheology, mucoadhesion and adhesiveness to facilitate its adhesion to the upper nasal mucosa. NLC-based in situ gel showed a 2-fold increase in nasal permeation of the drug over plain RV solution. In situ gelling NLCs showed a 3-fold increase in enzyme inhibition efficacy.

  7. Development of ocular drug delivery systems using molecularly imprinted soft contact lenses.

    Science.gov (United States)

    Tashakori-Sabzevar, Faezeh; Mohajeri, Seyed Ahmad

    2015-05-01

    Recently, significant advances have been made in order to optimize drug delivery to ocular tissues. The main problems in ocular drug delivery are poor bioavailability and uncontrollable drug delivery of conventional ophthalmic preparations (e.g. eye drops). Hydrogels have been investigated since 1965 as new ocular drug delivery systems. Increase of hydrogel loading capacity, optimization of drug residence time on the ocular surface and biocompatibility with the eye tissue has been the main focus of previous studies. Molecular imprinting technology provided the opportunity to fulfill the above-mentioned objectives. Molecularly imprinted soft contact lenses (SCLs) have high potentials as novel drug delivery systems for the treatment of eye disorders. This technique is used for the preparation of polymers with specific binding sites for a template molecule. Previous studies indicated that molecular imprinting technology could be successfully applied for the preparation of SCLs as ocular drug delivery systems. Previous research, particularly in vivo studies, demonstrated that molecular imprinting is a versatile and effective method in optimizing the drug release behavior and enhancing the loading capacity of SCLs as new ocular drug delivery systems. This review highlights various potentials of molecularly imprinted contact lenses in enhancing the drug-loading capacity and controlling the drug release, compared to other ocular drug delivery systems. We have also studied the effects of contributing factors such as the type of comonomer, template/functional monomer molar ratio, crosslinker concentration in drug-loading capacity, and the release properties of molecularly imprinted hydrogels.

  8. An emerging platform for drug delivery: aerogel based systems.

    Science.gov (United States)

    Ulker, Zeynep; Erkey, Can

    2014-03-10

    Over the past few decades, advances in "aerogel science" have provoked an increasing interest for these materials in pharmaceutical sciences for drug delivery applications. Because of their high surface areas, high porosities and open pore structures which can be tuned and controlled by manipulation of synthesis conditions, nanostructured aerogels represent a promising class of materials for delivery of various drugs as well as enzymes and proteins. Along with biocompatible inorganic aerogels and biodegradable organic aerogels, more complex systems such as surface functionalized aerogels, composite aerogels and layered aerogels have also been under development and possess huge potential. Emphasis is given to the details of the aerogel synthesis and drug loading methods as well as the influence of synthesis parameters and loading methods on the adsorption and release of the drugs. Owing to their ability to increase the bioavailability of low solubility drugs, to improve both their stability and their release kinetics, there are an increasing number of research articles concerning aerogels in different drug delivery applications. This review presents an up to date overview of the advances in all kinds of aerogel based drug delivery systems which are currently under investigation.

  9. AN OVERVIEW ON VARIOUS APPROACHES TO ORAL CONTROLLED DRUG DELIVERY SYSTEM VIA GASTRORETENTIVE DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Bhalla.Neetika

    2012-04-01

    Full Text Available In recent years scientific and technological advancements have been made in the research and development of oral drug delivery system. Oral sustained drug delivery system is complicated by limited gastric residence times (GRTs. In order to understand various physiological difficulties to achieve gastric retention, we have summarized important factors controlling gastric retention. To overcome these limitations, various approaches have been proposed to increase gastric residence of drug delivery systems in the upper part of the gastrointestinal tract includes floating drug dosage systems (FDDS, swelling or expanding systems , mucoadhesive systems , magnetic systems, modified-shape systems, high density system and other delayed gastric emptying devices.

  10. [A novel anticancer drug delivery system -DAC-70/CDDP].

    Science.gov (United States)

    Sugitachi, Akio; Otsuka, Koki; Fujisawa, Kentaro; Itabashi, Tetsuya; Akiyama, Yuji; Sasaki, Akira; Ikeda, Kenichiro; Yoshida, Yasuo; Takamori, Yoshimori; Kurozumi, Seiji; Mori, Takatoshi; Wakabayashi, Go

    2007-11-01

    We devised a muco-adhesive anticancer drug delivery system using 70% deacetylated chitin (DAC-70) and cisplatin (CDDP) and 5-fluorouracil (5-FU). The adhesive force between the system and human colonic mucosa was measured ex vivo, and a release profile of each drug was examined in vitro. Each system demonstrated a stronger muco-adhesive force at 37 degrees C than that of 25 degrees C. The CDDP-loaded system showed a sustained release of the drug while the 5-FU-loaded system exhibited an initial bursting of the agent. We presume that the release profile of CDDP and 5-FU is closely related to both degradability of the chitin and interactions between the chitin and each drug. The DAC-70/CDDP system would be clinically promising in loco-regional cancer chemotherapy.

  11. Engineering Stent Based Delivery System for Esophageal Cancer Using Docetaxel.

    Science.gov (United States)

    Shaikh, Mohsin; Choudhury, Namita Roy; Knott, Robert; Garg, Sanjay

    2015-07-01

    Esophageal cancer patients are often diagnosed as "advanced" cases. These patients are subjected to palliative stenting using self-expanding metallic stents (SEMS) to maintain oral alimentation. Unfortunately, SEMS get reoccluded due to tumor growth, in and over the stent struts. To investigate potential solutions to this problem, docetaxel (DTX) delivery films were prepared using PurSil AL 20 (PUS), which can be used as a covering material for the SEMS. Drug-polymer miscibility and interactions were studied. Bilayer films were prepared by adhering the blank film to the DTX loaded film in order to maintain the unidirectional delivery to the esophagus. In vitro release and the local DTX delivery were studied using in vitro permeation experiments. It was found that DTX and PUS were physically and chemically compatible. The bilayer films exhibited sustained release (>30 days) and minimal DTX permeation through esophageal tissues in vitro. The rate-determining step for the DTX delivery was calculated. It was found that >0.9 fraction of rate control lies with the esophageal tissues, suggesting that DTX delivery can be sustained for longer periods compared to the in vitro release observed. Thus, the bilayer films can be developed as a localized sustained delivery system in combination with the stent.

  12. Liposomal drug delivery systems: from concept to clinical applications.

    Science.gov (United States)

    Allen, Theresa M; Cullis, Pieter R

    2013-01-01

    The first closed bilayer phospholipid systems, called liposomes, were described in 1965 and soon were proposed as drug delivery systems. The pioneering work of countless liposome researchers over almost 5 decades led to the development of important technical advances such as remote drug loading, extrusion for homogeneous size, long-circulating (PEGylated) liposomes, triggered release liposomes, liposomes containing nucleic acid polymers, ligand-targeted liposomes and liposomes containing combinations of drugs. These advances have led to numerous clinical trials in such diverse areas as the delivery of anti-cancer, anti-fungal and antibiotic drugs, the delivery of gene medicines, and the delivery of anesthetics and anti-inflammatory drugs. A number of liposomes (lipidic nanoparticles) are on the market, and many more are in the pipeline. Lipidic nanoparticles are the first nanomedicine delivery system to make the transition from concept to clinical application, and they are now an established technology platform with considerable clinical acceptance. We can look forward to many more clinical products in the future.

  13. Emulsomes: An emerging vesicular drug delivery system

    Directory of Open Access Journals (Sweden)

    Bhawandeep Gill

    2012-01-01

    Full Text Available The oral route is the easiest, cost effective, and most vital method for drug administration. Therefore, improvement of dosage forms mainly for the prolonged release purpose has been a challenge for scientists. Vesicular drug delivery systems are developed with a purpose to overcome problems coupled with the drugs such a poor bioavailability, protection from harsh gastric environment, and from gastric enzymes, which degrade the drug. Vesicular drug delivery systems such as liposomes, emulsions, niosomes, proniosomes, solid lipid-nano particles, ethosomes, nanoparticles, and pharmacosomes, etc have gained much attention, but emulsomes have rouse as system, which bypasses many disadvantages associated with other systems, developed as novel lipoidal vesicular system with internal solid fat core surrounded by phospholipid bilayer. This technology is designed to act as vehicle for poorly soluble drugs. The drug is enclosed in the emulsomes and provide prolong existence of drug in systemic circulation. Furthermore, emulsomal-based formulations of genetic drugs such as antisense oligonucleotides and plasmids for gene therapy that have clear potential for systemic utility are increasingly available. This review addresses the concept of emulsomal drug delivery system, summarizes the success of emulsomes for the delivery of small molecules, and special attention has been paid to its formulation design, advantages, biopharmaceutical aspects, stability aspects, and various aspects related to drug delivery including future aspects.

  14. Diclofenac-loaded Eudragit S100 nanosuspension for ophthalmic delivery.

    Science.gov (United States)

    Ahuja, Munish; Dhake, Avinash S; Sharma, Surendera K; Majumdar, Dipak K

    2011-01-01

    In this study, diclofenac-loaded Eudragit S100-based nanosuspension was prepared by nanoprecipitation method and characterised for particle size, morphology, in vitro release, and for its in vivo ocular anti-inflammatory activity. The diclofenac-loaded Eudragit S100 nanosuspension was found to have a particle size of 172 nm, polydispersibility index of 0.14 and zeta potential of -23.7 +/- 6.07 mV, indicating that the nanosuspension is fairly stable. The nanosuspended particles were found to be spherical in shape. The nanosuspension was found to provide a sustained in vitro release, following the Higuchi square-root release kinetics. The results indicated that the nanosuspension released the drug by combination of dissolution and diffusion. The in vivo evaluation of nanosuspension in PGE(2)-induced ocular inflammation in rabbit model revealed a significantly (p  <  0.05) higher inhibition of PGE(2)-induced polymorphonuclear leukocytes migration and lid-closure scores as compared with the aqueous solution of diclofenac.

  15. STRATEGIES AND PROSPECTS OF NASAL DRUG DELIVERY SYSTEMS

    OpenAIRE

    Gannu Praveen Kumar

    2012-01-01

    The recent advancement of nasal drug delivery systems has increased enormously and is gaining significant importance. Intranasal therapy has been an accepted form of treatment in the Ayurvedic system of Indian Medicine. The non-invasive delivery of nasal drug delivery systems made to exploit for the development of successful treatment. The advantages, disadvantages, mechanism of action and application of nasal drug delivery system in local delivery, systematic delivery, nasal vaccines and CNS...

  16. Self-assembled liposome-loaded microbubbles: The missing link for safe and efficient ultrasound triggered drug-delivery.

    Science.gov (United States)

    Geers, Bart; Lentacker, Ine; Sanders, Niek N; Demeester, Joseph; Meairs, Stephen; De Smedt, Stefaan C

    2011-06-10

    Liposome-loaded microbubbles have been recently introduced as a promising drug delivery platform for ultrasound guided drug delivery. In this paper we design liposome-loaded (lipid-shelled) microbubbles through the simple self-assembly of the involved compounds in a single step process. We thoroughly characterized the liposome-loading of the microbubbles and evaluated the cell killing efficiency of this material using doxorubicin (DOX) as a model drug. Importantly, we observed that the DOX liposome-loaded microbubbles allowed killing of melanoma cells even at very low doses of DOX. These findings clearly prove the potential of liposome-loaded microbubbles for ultrasound targeted drug delivery to cancer tissues.

  17. CURRENT TRENDS IN PULSATILE DRUG DELIVERY SYSTEMS

    Directory of Open Access Journals (Sweden)

    S. R. Tajane et al.

    2012-01-01

    Full Text Available The purpose for this review on pulsatile drug delivery systems (PDDS is to compile the recent literatures with special focus on the different types and approaches involved in the development of the formulation. Pulsatile drug delivery system is the most interesting time and site-specific system. This system is designed for chronopharmacotherapy. Thus, to mimic the function of living systems and in view of emerging chronotherapeutic approaches, pulsatile delivery, which is meant to release a drug following programmed lag phase, has increasing interest in the recent years. Diseases wherein PDDS are promising include asthma, peptic ulcer, cardiovascular diseases, arthritis, and attention deficit syndrome in children, cancer, diabetes, and hypercholesterolemia. Pulsatile drug delivery system divided into 2 types’ preplanned systems and stimulus induced system, preplanned systems based on osmosis, rupturable layers, and erodible barrier coatings. Stimuli induced system based on electrical, temperature and chemically induced systems. This review also summarizes some current PDDS already available in the market. These systems are useful to several problems encountered during the development of a pharmaceutical dosage form.

  18. Goals for Postsecondary Instructional Delivery Systems.

    Science.gov (United States)

    Knapp, Stuart E.; Valentine, Carol A.

    Extrapolating from the trends in postsecondary instructional delivery systems identified by Brown, Lewis and Harcleroad, this report attempts to identify how these trends might be implemented in Oregon. Separating the systems into technology-centered and people-centered, the report proposes future applications of dial access systems, self learning…

  19. Microemulsion: As Excellent Drug Delivery System

    Directory of Open Access Journals (Sweden)

    Pathan Maksud

    2012-09-01

    Full Text Available Today though the oral drug delivery system is dominant still it is found to be need of ideal transdermal drug delivery system. “A micro emulsion is a system of water, oil and an amphiphile which is a single optically isotropic and thermodynamically stable liquid solution”. Microemulsions offer several advantages as drug delivery systems as these are thermodynamically stable and stability allows for self emulsification of the system with microemulsion acting as supersolvent of the drugs which are poorly or insoluble in water. They are preferred more as compared to conventional emulsions due stability. The dispersed phase mainly acts as the solvent for the water insoluble drug. Microemulsions have been proved to increase the cutaneous absorption of both lipophilic and hydrophilic API’s when compared to conventional vehicles.

  20. RECENT TRENDS IN DENTAL DRUG DELIVERY SYSTEMS

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    Sharma Nishu

    2013-07-01

    Full Text Available Controlled release local drug delivery systems offer advantages compared to systemic dosage forms for many dental diseases like gingivitis, periodontitis. The objective of this literature survey was to gain knowledge about various dental drug delivery systems for targeted delivery of the drug. The polymer ethyl cellulose was used in the formulation of dental films. The dental film was then evaluated for various parameters like thickness, folding endurance and weight variation and content uniformity, in vitro and in vivo study. There has been a great attention in using iontophoretic technique for the transdermal drug delivery of medications, both ionic and non ionic. This technique of facilitated movement of ions across a membrane under the influence of an externally applied electric potential difference is one of the most promising physical skin penetrations enhancing method. Another novel approach is the use of lasers in dentistry. Lasers can be used in both hard and soft tissue applications including laser bleaching, frenectomy, gingivectomy, caries removal etc. Drugs delivery via the buccal routs using bio adhesive dosage forms offers such a novel route of drugs administration. This route has been used successfully for the systematic delivery of number of drugs candidates. Problems such as high first pass metabolisms and drugs degradation in the gastrointestinal tract can be circumvented by administrating the drug buccal routes.

  1. Propulsion and Power Rapid Response R&D Support Delivery Order 0041: Power Dense Solid Oxide Fuel Cell Systems: High Performance, High Power Density Solid Oxide Fuel Cells - Materials and Load Control

    Science.gov (United States)

    2008-12-01

    Reno, Nevada, Jan. 9-12, 2006. Jan. 1997. [4] S. Pasricha and S. R. Shaw, “A Dynamic PEM Fuelcell Model ”, IEEE Transactions on Energy Conversion...Abstract concluded on reverse 15. SUBJECT TERMS solid oxide fuel cell, SOFC, solid oxide fuel cell electrodes , SOFC systems, hybrid power systems...Fuel Cells: Load Control: This report provides a physically-based model for design and optimization of a fuel cell powered electric propulsion

  2. Delivery systems for gene therapy

    Directory of Open Access Journals (Sweden)

    Shrikant Mali

    2013-01-01

    Full Text Available The structure of DNA was unraveled by Watson and Crick in 1953, and two decades later Arber, Nathans and Smith discovered DNA restriction enzymes, which led to the rapid growth in the field of recombinant DNA technology. From expressing cloned genes in bacteria to expressing foreign DNA in transgenic animals, DNA is now slated to be used as a therapeutic agent to replace defective genes in patients suffering from genetic disorders or to kill tumor cells in cancer patients. Gene therapy provides modern medicine with new perspectives that were unthinkable two decades ago. Progress in molecular biology and especially, molecular medicine is now changing the basics of clinical medicine. A variety of viral and non-viral possibilities are available for basic and clinical research. This review summarizes the delivery routes and methods for gene transfer used in gene therapy.

  3. Pulsatile drug delivery systems: An approach for controlled drug delivery

    Directory of Open Access Journals (Sweden)

    Arora Shweta

    2006-01-01

    Full Text Available Pulsatile systems are gaining a lot of interest as they deliver the drug at the right site of action at the right time and in the right amount, thus providing spatial and temporal delivery and increasing patient compliance. These systems are designed according to the circadian rhythm of the body. The principle rationale for the use of pulsatile release is for the drugs where a constant drug release, i.e., a zero-order release is not desired. The release of the drug as a pulse after a lag time has to be designed in such a way that a complete and rapid drug release follows the lag time. Various systems like capsular systems, osmotic systems, single- and multiple-unit systems based on the use of soluble or erodible polymer coating and use of rupturable membranes have been dealt with in the article. It summarizes the latest technological developments, formulation parameters, and release profiles of these systems. Products available as once-a-daily formulation based on Pulsatile release like Pulsincap ®, Ritalin ®, and Pulsys ® are also covered in the review. These systems are beneficial for the drugs having chronopharmacological behaviour where night time dosing is required and for the drugs having high first-pass effect and having specific site of absorption in GIT. Drugs used in asthmatic patients and patients suffering from rheumatoid arthritis are also discussed along with many other examples.

  4. Nanostructured lipid carriers system: recent advances in drug delivery.

    Science.gov (United States)

    Iqbal, Md Asif; Md, Shadab; Sahni, Jasjeet Kaur; Baboota, Sanjula; Dang, Shweta; Ali, Javed

    2012-12-01

    Nanostructured lipid carrier (NLC) is second generation smarter drug carrier system having solid matrix at room temperature. This carrier system is made up of physiological, biodegradable and biocompatible lipid materials and surfactants and is accepted by regulatory authorities for application in different drug delivery systems. The availability of many products in the market in short span of time reveals the success story of this delivery system. Since the introduction of the first product, around 30 NLC preparations are commercially available. NLC exhibit superior advantages over other colloidal carriers viz., nanoemulsions, polymeric nanoparticles, liposomes, SLN etc. and thus, have been explored to more extent in pharmaceutical technology. The whole set of unique advantages such as enhanced drug loading capacity, prevention of drug expulsion, leads to more flexibility for modulation of drug release and makes NLC versatile delivery system for various routes of administration. The present review gives insights on the definitions and characterization of NLC as colloidal carriers including the production techniques and suitable formulations. This review paper also highlights the importance of NLC in pharmaceutical applications for the various routes of drug delivery viz., topical, oral, pulmonary, ocular and parenteral administration and its future perspective as a pharmaceutical carrier.

  5. PULSATILE DRUG DELIVERY SYSTEMS: RECENT TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Abdul Sayeed*, Md. M. Hamed , Mohd. Rafiq and Nahid Ali

    2013-03-01

    Full Text Available ABSTRACT: Pulsatile Drug Delivery Systems are gaining a lot of interest as they deliver the drug at the right place at the right time and in the right amount, thus providing spatial and temporal delivery and increasing patient compliance. These systems are designed according to the circadian rhythm of the body. The principle rationale for the use of pulsatile release of the drugs is where a constant drug release is not desired. A pulse has to be designed in such a way that a complete and rapid drug release is achieved after the lag time. Various systems like capsular systems, osmotic systems, single- and multiple-unit systems based on the use of soluble or erodible polymer coating and use of rupturable membranes have been dealt with in the article. It summarizes the latest technological developments, formulation parameters, and release profiles of these systems. These systems are beneficial for the drugs having chronopharmacological behavior where night time dosing is required, such as anti-arhythmic and anti-asthmatic. Current review article discussed the reasons for development of pulsatile drug delivery system, types of the disease in which pulsatile release is required, classification, advantages, limitation, and future aspects of pulsatile drug delivery system.

  6. Halobetasol propionate-loaded solid lipid nanoparticles (SLN) for skin targeting by topical delivery.

    Science.gov (United States)

    Bikkad, Mahesh L; Nathani, Ajaz H; Mandlik, Satish K; Shrotriya, Shilpa N; Ranpise, Nisharani S

    2014-06-01

    The clinical use of halobetasol propionate (HP) is related to some adverse effects like irritation, pruritus and stinging. The purpose of this work was to construct HP-loaded solid lipid nanoparticles (HP-SLN) formulation with skin targeting to minimizing the adverse side effects and providing a controlled release. HP-SLN were prepared by solvent injection method and formula was optimized by the application of 3(2) factorial design. The nanoparticulate dispersion was evaluated for particle size and entrapment efficiency (EE). Optimized batch was characterized for differential scanning calorimetry (DSC), scanning electron microscopy, X-ray diffraction study and finally incorporated into polymeric gels of carbopol for convenient application. The nanoparticulate gels were evaluated comparatively with the commercial product with respect to ex-vivo skin permeation and deposition study on human cadaver skins and finally skin irritation study. HP-SLN showed average size between 200 nm and 84-94% EE. DSC studies revealed no drug-excipient incompatibility and amorphous dispersed of HP in SLN. Ex vivo study of HP-SLN loaded gel exhibited prolonged drug release up to 12 h where as in vitro drug deposition and skin irritation studies showed that HP-SLN formulation can avoid the systemic uptake, better accumulative uptake of the drug and nonirritant to the skin compared to marketed formulation. These results indicate that the studied HP-SLN formulation represent a promising carrier for topical delivery of HP, having controlled drug release, and potential of skin targeting with no skin irritation.

  7. Intelligent System for Radial Distribution Load Flow

    Directory of Open Access Journals (Sweden)

    Vaishali Holkar

    2012-10-01

    Full Text Available This paper shows an application of Artificial Neural Networks (ANNs to determine the bus voltages and phase angles of a radial distribution system, without executing the complicated load flow algorithm, for any given load. The performance of the conventional load flow methods such as Newtoh-Raphson load flow, Fast decoupled load flow is found to be very poor under critical conditions such as high R/X ratio, heavily loading condition etc.To overcome the limitations of these regularly used methods a simple and reliable ladder iterative technique is used for solving the power balance equations of radial distribution system (RDS. The proposed method make use of a multi-layer feed forward ANN with error back propagation learning algorithm for calculation of bus voltages and its angles. A sample IEEE 33-bus is extensively tested with the proposed ANN based approach indicating its viability for RDS load flow assessment and results are presented.

  8. Aerial Delivery Systems and Technologies (Review Paper

    Directory of Open Access Journals (Sweden)

    Balraj Gupta

    2010-03-01

    Full Text Available Aerial Delivery Research & Development Establishment (ADRDE was started at Kanpur during latter part of 1950's consisting of two Aerial Delivery Sections primarily for the indigenisation of Parachutes and related equipment for Para-dropping of men and materials. Today, the charter of ADRDE includes design & development of parachutes, Aerostat Systems, Aircraft Arrester Barrier Systems and Heavy-Drop Systems for both military and civilian applications. The technological competence built in Aeronautical, Textile, Mechanical and Electronics engineering has imparted ADRDE, a unique combination of know-how and capabilities to evolve new solutions in these fields, with emphasis on quality assurance. This paper highlights the design and development of technologies developed by ADRDE to stengthen the India's aerial delivery system and its future plans.Defence Science Journal, 2010, 60(2, pp.124-136, DOI:http://dx.doi.org/10.14429/dsj.60.326

  9. Local delivery of cannabinoid-loaded microparticles inhibits tumor growth in a murine xenograft model of glioblastoma multiforme.

    Directory of Open Access Journals (Sweden)

    Dolores Hernán Pérez de la Ossa

    Full Text Available Cannabinoids, the active components of marijuana and their derivatives, are currently investigated due to their potential therapeutic application for the management of many different diseases, including cancer. Specifically, Δ(9-Tetrahydrocannabinol (THC and Cannabidiol (CBD - the two major ingredients of marijuana - have been shown to inhibit tumor growth in a number of animal models of cancer, including glioma. Although there are several pharmaceutical preparations that permit the oral administration of THC or its analogue nabilone or the oromucosal delivery of a THC- and CBD-enriched cannabis extract, the systemic administration of cannabinoids has several limitations in part derived from the high lipophilicity exhibited by these compounds. In this work we analyzed CBD- and THC-loaded poly-ε-caprolactone microparticles as an alternative delivery system for long-term cannabinoid administration in a murine xenograft model of glioma. In vitro characterization of THC- and CBD-loaded microparticles showed that this method of microencapsulation facilitates a sustained release of the two cannabinoids for several days. Local administration of THC-, CBD- or a mixture (1:1 w:w of THC- and CBD-loaded microparticles every 5 days to mice bearing glioma xenografts reduced tumour growth with the same efficacy than a daily local administration of the equivalent amount of those cannabinoids in solution. Moreover, treatment with cannabinoid-loaded microparticles enhanced apoptosis and decreased cell proliferation and angiogenesis in these tumours. Our findings support that THC- and CBD-loaded microparticles could be used as an alternative method of cannabinoid delivery in anticancer therapies.

  10. Pharmacosomes: A Potential Vesicular Drug Delivery System

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    D. Nagasamy Venkatesh

    2014-04-01

    Full Text Available Lipid based drug delivery systems have been examined in various studies and exhibited their potential in controlled and targeted drug delivery. Pharmacosomes, a novel vesicular drug delivery system, offering a unique advantage over liposomes and niosomes, and serve as potential alternative to these conventional vesicles. They constitute an amphiphilic phospholipid complex with drug bearing an active hydrogen atom covalently that bind to phospholipids. They provide an efficient delivery of drug required at the site of action, which ultimately reduces the drug toxicity with reduced adverse effects and also reduces the cost of therapy by imparting better biopharmaceutical properties to the drug, resulting in increases bioavailability, especially in case of poorly soluble drugs. As the system is formed by binding the drug (pharmakon to carrier (soma, they are termed as pharmacosomes. Depending upon the chemical structure of the drug lipid complex they may exist as ultrafine vesicular, micellar and hexagonal aggregate. Drug having active hydrogen group such as carboxyl, hydroxyl group can be esterified to lipids, resulting in amphiphilic compound. Pharmacosomes are widely used as carriers for various non-steroidal anti-inflammatory drugs, proteins, cardiovascular and antineoplastic drugs. The release of drug from pharmacosomes is generally governed by the process of enzymatic reaction and acid hydrolysis. Here, in the present review paper we have discussed the potential of pharmacosomes as a controlled and targeted drug delivery system and highlighted the method of preparation and characterization.

  11. Study on the colonic stability of curcumin-piperine dual drug loaded self-microemulsifying drug ;delivery system%姜黄素-胡椒碱复方自微乳结肠稳定性研究

    Institute of Scientific and Technical Information of China (English)

    李秋萍; 蒋俏丽; 翟文文; 戴俊东

    2015-01-01

    目的:考察姜黄素—胡椒碱复方自微乳给药系统对姜黄素在结肠部位稳定性的改善作用,为其治疗结肠炎或结肠癌等结肠局部疾病提供科学依据。方法通过HPLC测定姜黄素的含量,37℃体外考察并比较姜黄素溶液、姜黄素—胡椒碱混合溶液及姜黄素—胡椒碱复方自微乳在人工结肠液及小鼠结肠组织匀浆液中的稳定性。结果37℃人工结肠液中孵育24小时后,姜黄素溶液、姜黄素—胡椒碱混合溶液和姜黄素—胡椒碱复方自微乳中姜黄素的降解百分率分别为19.93%、12.67%和10.50%,降解过程符合一级动力学方程,半衰期分别为19.67小时、57.87小时和75.23小时;37℃小鼠结肠组织匀浆液中孵育8小时后,姜黄素溶液、姜黄素—胡椒碱混合溶液和姜黄素-胡椒碱复方自微乳中姜黄素的降解百分率分别为19.96%、14.49%和4.63%。结论姜黄素-胡椒碱复方自微乳给药系统可以显著改善姜黄素在结肠部位的的稳定性(P<0.05),有望增强对结肠局部疾病的治疗效果。%Objective To investigate whether the curcumin-piperine dual drug loaded self-microe-mulsifying drug delivery system ( Cur-PIP-SMEDDS ) could enhance the curcumin’s stability in the colon site. This study could provide scientific basis for the treatment of colonic disease, such as colitis and colon cancer. Methods HPLC method was established for the determination of the content of curcumin. To determine whether Cur-PIP-SMEDDS is more stable in the colonic site, free curcumin, curcumin-piperine mixture and Cur-PIP-SMEDDS were incubated in the artificial colon fluid and the mice colonic tissue homogenized mixture at 37℃, and sampled periodically to determine the concentration of curcumin by HPLC. Results The degradation percentage of curcumin in free curcumin solution, curcumin-piperine mixture, and Cur-PIP-SMEDDS were 19. 93%, 12. 67% and 10. 50% respectively after incubation

  12. FLOATING DRUG DELIVERY SYSTEM - CHRONOTHERAPEUTIC APPROACH

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    Vishal Kalal

    2011-04-01

    Full Text Available The purpose of writing this review on the floating drug delivery systems (FDDS was to compile the recent literature with special focus on the principal mechanism of floatation to achieve gastric retention. FDDS is one of the approaches in chronotherapeutic drug delivery. In the past reviews of FDDS the physiological and formulation variables affecting gastric retention, approaches to design single-unit and multiple-unit floating systems, their classification and formulation aspects have been covered. This review summarizes the special focus on chronotherapeutics, diseases affected by biological rhythm, its importance, advantages, various approaches in Chronotherapeutic drug delivery and applications of FDDS. These systems are useful for several problems encountered during the development of a pharmaceutical dosage forms.

  13. A patchless dissolving microneedle delivery system enabling rapid and efficient transdermal drug delivery.

    Science.gov (United States)

    Lahiji, Shayan F; Dangol, Manita; Jung, Hyungil

    2015-01-21

    Dissolving microneedles (DMNs) are polymeric, microscopic needles that deliver encapsulated drugs in a minimally invasive manner. Currently, DMN arrays are superimposed onto patches that facilitate their insertion into skin. However, due to wide variations in skin elasticity and the amount of hair on the skin, the arrays fabricated on the patch are often not completely inserted and large amount of loaded materials are not delivered. Here, we report "Microlancer", a novel micropillar based system by which patients can self-administer DMNs and which would also be capable of achieving 97 ± 2% delivery efficiency of the loaded drugs regardless of skin type or the amount of hair on the skin in less than a second.

  14. Nanotechnology-based drug delivery systems

    Directory of Open Access Journals (Sweden)

    Singh Baljit

    2007-12-01

    Full Text Available Abstract Nanoparticles hold tremendous potential as an effective drug delivery system. In this review we discussed recent developments in nanotechnology for drug delivery. To overcome the problems of gene and drug delivery, nanotechnology has gained interest in recent years. Nanosystems with different compositions and biological properties have been extensively investigated for drug and gene delivery applications. To achieve efficient drug delivery it is important to understand the interactions of nanomaterials with the biological environment, targeting cell-surface receptors, drug release, multiple drug administration, stability of therapeutic agents and molecular mechanisms of cell signalling involved in pathobiology of the disease under consideration. Several anti-cancer drugs including paclitaxel, doxorubicin, 5-fluorouracil and dexamethasone have been successfully formulated using nanomaterials. Quantom dots, chitosan, Polylactic/glycolic acid (PLGA and PLGA-based nanoparticles have also been used for in vitro RNAi delivery. Brain cancer is one of the most difficult malignancies to detect and treat mainly because of the difficulty in getting imaging and therapeutic agents past the blood-brain barrier and into the brain. Anti-cancer drugs such as loperamide and doxorubicin bound to nanomaterials have been shown to cross the intact blood-brain barrier and released at therapeutic concentrations in the brain. The use of nanomaterials including peptide-based nanotubes to target the vascular endothelial growth factor (VEGF receptor and cell adhesion molecules like integrins, cadherins and selectins, is a new approach to control disease progression.

  15. Doxorubicin liposome-loaded microbubbles for contrast imaging and ultrasound-triggered drug delivery.

    Science.gov (United States)

    Escoffre, Jean-Michel; Mannaris, Christophoros; Geers, Bart; Novell, Anthony; Lentacker, Ine; Averkiou, Michalakis; Bouakaz, Ayache

    2013-01-01

    Targeted drug delivery under image guidance is gaining more interest in the drug-delivery field. The use of microbubbles as contrast agents in diagnostic ultrasound provides new opportunities in noninvasive image-guided drug delivery. In the present study, the imaging and therapeutic properties of novel doxorubicin liposome-loaded microbubbles are evaluated. The results showed that at scanning settings (1.7 MHz and mechanical index 0.2), these microbubbles scatter sufficient signal for nonlinear ultrasound imaging and can thus be imaged in real time and be tracked in vivo. In vitro therapeutic evaluation showed that ultrasound at 1 MHz and pressures up to 600 kPa in combination with the doxorubicin liposomeloaded microbubbles induced 4-fold decrease of cell viability compared with treatment with free doxorubicin or doxorubicin liposome-loaded microbubbles alone. The therapeutic effectiveness is correlated to an ultrasound-triggered release of doxorubicin from the liposomes and an enhanced uptake of the free doxorubicin by glioblastoma cells. The results obtained demonstrate that the combination of ultrasound and the doxorubicin liposome-loaded microbubbles can provide a new method of noninvasive image-guided drug delivery.

  16. Carboxymethyl cellulose (CMC)-loaded Co-Cu doped manganese ferrite nanorods as a new dual-modal simultaneous contrast agent for magnetic resonance imaging and nanocarrier for drug delivery system

    Science.gov (United States)

    Abbasi Pour, Sajjad; Shaterian, Hamid Reza; Afradi, Mojgan; Yazdani-Elah-Abadi, Afshin

    2017-09-01

    We synthesized Co0.25Cu0.25Mn0.5Fe2O4@CMC (CCMFe2O4@CMC) nanorods as a new dual-modal simultaneous for magnetic resonance imaging contrast agent and nanocarrier for drug delivery system. Impact of CCMFe2O4@CMC nanorods were investigated on the longitudinal (T1), transverse (T2) and transverse (T2∗) relaxation times for in vitro MRI contrast agent in water and also for drug delivery system, L-dopa was coated on CCMFe2O4@CMC nanorods and then in vitro drug release test was carried out at three PHs values and different temperatures. In vitro MR imaging demonstrated that r2 value of CCMFe2O4@CMC nanorods is 138.33 mM-1 s-1, CCMFe2O4@CMC is useful as T2 contrast agent relative to other T2 contrast agants. In vitro drug release test shows the amount of released L-dopa from CCMFe2O4@CMC nanorods at medium with pH = 1.2 is more than pH = 5.3 and 7.4.

  17. Controlled delivery of hollow corn protein nanoparticles via non-toxic crosslinking: in vivo and drug loading study.

    Science.gov (United States)

    Xu, Helan; Shen, Li; Xu, Lan; Yang, Yiqi

    2015-02-01

    In this research, controlled delivery of hollow nanoparticles from zein, the corn storage protein, to different organs of mice was achieved via crosslinking using citric acid, a non-toxic polycarboxylic acid derived from starch. Besides, crosslinking significantly enhanced water stability of nanoparticles while preserving their drug loading efficiency. Protein nanoparticles have been widely investigated as vehicles for delivery of therapeutics. However, protein nanoparticles were not stable in physiological conditions, easily cleared by mononuclear phagocyte system (MPS), and thus mainly accumulated and degraded in spleen and liver, the major MPS organs. Effective delivery to major non-MPS organs, such as kidney, was usually difficult to achieve, as well as long resident time of nanoparticles. In this research, hollow zein nanoparticles were chemically crosslinked with citric acid. Controlled delivery and prolonged accumulation of the nanoparticles in kidney, one major non-MPS organ, were achieved. The nanoparticles showed improved stability in aqueous environment at pH 7.4 without affecting the adsorption of 5-FU, a common anticancer drug. In summary, citric acid crosslinked hollow zein nanoparticles could be potential vehicles for controllable delivery of anticancer therapeutics.

  18. Waste Feed Delivery Transfer System Analysis

    Energy Technology Data Exchange (ETDEWEB)

    JULYK, L.J.

    2000-05-05

    This document provides a documented basis for the required design pressure rating and pump pressure capacity of the Hanford Site waste-transfer system in support of the waste feed delivery to the privatization contractor for vitrification. The scope of the analysis includes the 200 East Area double-shell tank waste transfer pipeline system and the associated transfer system pumps for a11 Phase 1B and Phase 2 waste transfers from AN, AP, AW, AY, and A2 Tank Farms.

  19. Status of the CLIC Beam Delivery System

    CERN Document Server

    Tomás, R; Resta López, J; Rumolo, G; Schulte, D; Schuler, P; Bolzon, B; Brunetti, L; Brunetti, L; Geffroy, N; Jeremie, A; Seryi, A; Angal-Kalinin, D; Jackson, F

    2010-01-01

    The CLIC Beam Delivery System (BDS) is experiencing the careful revision from a large number of world wide experts. This was particularly enhanced by the successful CLIC’08 workshop held at CERN. Numerous new ideas, improvements and critical points are arising, establishing the path towards the Conceptual Design Report by 2010.

  20. Auditing Information System : Delivery Product Service

    Directory of Open Access Journals (Sweden)

    Purwoko Purwoko

    2011-05-01

    Full Text Available Purpose of the research is to ensure the securities of information system asset and to ensure if informa-tion system support the operational and data collected was valid. Research method that used in this research were library studies and field studies. Field studies such an observation, questioner, and inter-view. the expected result are founding the weakness of security management control, operational man-agement control, input control, and output control of risk happened in the company. Conclusion of this research are the system on the company work good and there’s no potential risk happened and make an impact to the delivery process of information system.Index Terms - Auditing Information system, Delivery product process.

  1. Liposomes as a gene delivery system

    Directory of Open Access Journals (Sweden)

    C. Ropert

    1999-02-01

    Full Text Available Gene therapy is an active field that has progressed rapidly into clinical trials in a relatively short time. The key to success for any gene therapy strategy is to design a vector able to serve as a safe and efficient gene delivery vehicle. This has encouraged the development of nonviral DNA-mediated gene transfer techniques such as liposomes. Many liposome-based DNA delivery systems have been described, including molecular components for targeting given cell surface receptors or for escaping from the lysosomal compartment. Another recent technology using cationic lipids has been evaluated and has generated substantial interest in this approach to gene transfer.

  2. Targeted liposome-loaded microbubbles for cell-specific ultrasound-triggered drug delivery.

    Science.gov (United States)

    Geers, Bart; De Wever, Olivier; Demeester, Joseph; Bracke, Marc; De Smedt, Stefaan C; Lentacker, Ine

    2013-12-01

    One of the main problems in cancer treatment is disease relapse through metastatic colonization, which is caused by circulating tumor cells (CTCs). This work reports on liposome-loaded microbubbles targeted to N-cadherin, a cell-cell adhesion molecule expressed by CTCs. It is shown that such microbubbles can indeed bind to N-cadherin at the surface of HMB2 cells. Interestingly, in a mixture of cells with and without N-cadherin expression, binding of the liposome-loaded microbubbles mainly occurs to the N-cadherin-expressing cells. Importantly, applying ultrasound results in the intracellular delivery of a model drug (loaded in the liposomes) in the N-cadherin-expressing cells only. As described in this paper, such liposome-loaded microbubbles may find application as theranostics and in devices aimed for the specific killing of CTCs in blood.

  3. Metal organic frameworks as a drug delivery system for flurbiprofen

    Directory of Open Access Journals (Sweden)

    AL Haydar M

    2017-09-01

    Full Text Available Muder AL Haydar,1,2 Hussein Rasool Abid,3,4 Bruce Sunderland,2 Shaobin Wang5,6 1Pharmaceutics Department, College of the Pharmacy, University of Kerbala, Kerbala, Iraq; 2Pharmaceutics Department, School of Pharmacy, Faculty of Health Sciences, Curtin University, Perth, WA, Australia; 3Department of Chemical Engineering, Curtin University, Perth, WA, Australia; 4College of Applied Medical Sciences, University of Kerbala, Kerbala, Iraq; 5School of Pharmacy, Faculty of Health Sciences, Curtin University, Perth, WA, Australia; 6Department of Chemical Engineering, School of Chemical and Petroleum Engineering, Faculty of Science and Engineering, Curtin University, Perth, WA, Australia Background: Metal organic frameworks (MOFs have attracted more attention in the last decade because of a suitable pore size, large surface area, and high pore volume. Developing biocompatible MOFs such as the MIL family as a drug delivery system is possible. Purpose: Flurbiprofen (FBP, a nonsteroidal anti-inflammatory agent, is practically insoluble in aqueous solution, and, therefore, needs suitable drug delivery systems. Different biocompatible MOFs such as Ca-MOF and Fe-MILs (53, 100, and 101 were synthesized and employed for FBP delivery. Patients and methods: A sample of 50 mg of each MOF was mixed and stirred for 24 h with 10 mL of 5 mg FBP in acetonitrile (40% in a sealed container. The supernatant of the mixture after centrifuging was analyzed by high-performance liquid chromatography to determine the loaded quantity of FBP on the MOF. The overnight-dried solid material after centrifuging the mixture was analyzed for loading percent using X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, nuclear magnetic resonance, and FBP release profile. Results: The loading values of FBP were achieved at 10.0%±1%, 20%±0.8%, 37%±2.3%, and 46%±3.1% on Ca-MOF, Fe-MIL-53, Fe-MIL-101, and Fe-MIL-100, respectively. The FBP release

  4. New drug candidates for liposomal delivery identified by computer modeling of liposomes' remote loading and leakage.

    Science.gov (United States)

    Cern, Ahuva; Marcus, David; Tropsha, Alexander; Barenholz, Yechezkel; Goldblum, Amiram

    2017-02-16

    Remote drug loading into nano-liposomes is in most cases the best method for achieving high concentrations of active pharmaceutical ingredients (API) per nano-liposome that enable therapeutically viable API-loaded nano-liposomes, referred to as nano-drugs. This approach also enables controlled drug release. Recently, we constructed computational models to identify APIs that can achieve the desired high concentrations in nano-liposomes by remote loading. While those previous models included a broad spectrum of experimental conditions and dealt only with loading, here we reduced the scope to the molecular characteristics alone. We model and predict API suitability for nano-liposomal delivery by fixing the main experimental conditions: liposome lipid composition and size to be similar to those of Doxil® liposomes. On that basis, we add a prediction of drug leakage from the nano-liposomes during storage. The latter is critical for having pharmaceutically viable nano-drugs. The "load and leak" models were used to screen two large molecular databases in search of candidate APIs for delivery by nano-liposomes. The distribution of positive instances in both loading and leakage models was similar in the two databases screened. The screening process identified 667 molecules that were positives by both loading and leakage models (i.e., both high-loading and stable). Among them, 318 molecules received a high score in both properties and of these, 67 are FDA-approved drugs. This group of molecules, having diverse pharmacological activities, may be the basis for future liposomal drug development.

  5. Construction of paclitaxel-loaded poly (2-hydroxyethyl methacrylate)-g-poly (lactide)-1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine copolymer nanoparticle delivery system and evaluation of its anticancer activity.

    Science.gov (United States)

    Ma, Xiaowei; Wang, Huan; Jin, Shubin; Wu, Yan; Liang, Xing-Jie

    2012-01-01

    There is an urgent need to develop drug-loaded biocompatible nanoscale packages with improved therapeutic efficacy for effective clinical treatment. To address this need, a novel poly (2-hydroxyethyl methacrylate)-poly (lactide)-1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine [PHEMA-g-(PLA-DPPE)] copolymer was designed and synthesized to enable these nanoparticles to be pH responsive under pathological conditions. The structural properties and thermal stability of the copolymer was measured and confirmed by Fourier transform infrared spectroscopy, nuclear magnetic resonance, and thermogravimetric analysis. In order to evaluate its feasibility as a drug carrier, paclitaxel-loaded PHEMA-g-(PLA-DPPE) nanoparticles were prepared using the emulsion-solvent evaporation method. The PHEMA-g-(PLA-DPPE) nanoparticles could be efficiently loaded with paclitaxel and controlled to release the drug gradually and effectively. In vitro release experiments demonstrated that drug release was faster at pH 5.0 than at pH 7.4. The anticancer activity of the PHEMA-g-(PLA-DPPE) nanoparticles was measured in breast cancer MCF-7 cells in vivo and in vitro. In comparison with the free drug, the paclitaxel-loaded PHEMA-g-(PLA-DPPE) nanoparticles could induce more significant tumor regression. This study indicates that PHEMA-g-(PLA-DPPE) nanoparticles are promising carriers for hydrophobic drugs. This system can passively target cancer tissue and release drugs in a controllable manner, as determined by the pH value of the area in which the drug accumulates.

  6. A novel doxorubicin-loaded in situ forming gel based high concentration of phospholipid for intratumoral drug delivery.

    Science.gov (United States)

    Wu, Wenqi; Chen, Hui; Shan, Fengying; Zhou, Jing; Sun, Xun; Zhang, Ling; Gong, Tao

    2014-10-06

    The purpose of this study was to develop a safe and effective drug delivery system for local chemotherapy. A novel injectable in-situ-forming gel system was prepared using small molecule materials, including phospholipids, medium chain triglycerides (MCTs), and ethanol. Thus, this new sustained release system was named PME (first letter of phospholipids, MCT, and ethanol). PME has a well-defined molecule structure, a high degree of safety, and better biocompatible characteristics. It was in sol state with low viscosity in vitro and turned into a solid or semisolid gel in situ after injection. When loaded with doxorubicin (Dox), PME-D (doxorubicin-loaded PME) exhibited notably antitumor efficiency in S180 sarcoma tumors bearing mice after a single intratumoral injection. In vitro, PME-D had remarkable antiproliferative efficacies against MCF-7 breast cancer cells for over 5 days. Moreover, the initial burst effect can hardly be observed from PME system, which was different from many other in-situ-forming gels. The in vivo biodistribution study showed the high Dox concentration in tumors compared with other major organs after PME-D intratumoral administration. The strong signal in tumors was retained for more than 14 days after one single injection. The high concentration of Dox in tumor and long-term retention may explain the superior therapeutic efficacy and reduced side effects. The PME-D in-situ-forming gel system is a promising drug delivery system for local chemotherapy.

  7. Impact of chitosan composites and chitosan nanoparticle composites on various drug delivery systems: A review

    Directory of Open Access Journals (Sweden)

    M.Abd Elgadir

    2015-12-01

    Full Text Available Chitosan is a promising biopolymer for drug delivery systems. Because of its beneficial properties, chitosan is widely used in biomedical and pharmaceutical fields. In this review, we summarize the physicochemical and drug delivery properties of chitosan, selected studies on utilization of chitosan and chitosan-based nanoparticle composites in various drug delivery systems, and selected studies on the application of chitosan films in both drug delivery and wound healing. Chitosan is considered the most important polysaccharide for various drug delivery purposes because of its cationic character and primary amino groups, which are responsible for its many properties such as mucoadhesion, controlled drug release, transfection, in situ gelation, and efflux pump inhibitory properties and permeation enhancement. This review can enhance our understanding of drug delivery systems particularly in cases where chitosan drug-loaded nanoparticles are applied.

  8. NOVEL PARADIGMS IN MUCOADHESIVE DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Deepak Sharma et al

    2012-08-01

    Full Text Available Mucoadhesion is a field of current interest in the design of drug delivery systems. Mucoadhesion is commonly defined as the adhesion between two materials, at least one of which is a mucosal surface. Mucoadhesive drug delivery system may be designed to enable prolonged residence time of the dosage form at the site of application or absorption and facilitate an intimate contact of the dosage form with the underline absorption surface. Extending the residence time of a dosage form at a particular site and controlling the release of drug from the dosage form are useful especially for achieving controlled plasma level of the drug as well as improving bioavailability. Application of these dosage forms to mucosal surfaces may be of benefit to drug molecules not amenable to the oral route, such as those that undergo acid degradation or extensive first-pass metabolism. The present review describes mucoadhesion, mucoadhesive polymers and use of these polymers in designing different types of mucoadhesive gastrointestinal, nasal, ocular, vaginal and rectal drug delivery systems. The research on mucoadhesives, however, is still in its early stage, and further advances need to be made for the successful translation of the concept into practical application in controlled drug delivery.

  9. Importance of novel drug delivery systems in herbal medicines

    OpenAIRE

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

    2010-01-01

    Novel drug delivery system is a novel approach to drug delivery that addresses the limitations of the traditional drug delivery systems. Our country has a vast knowledge base of Ayurveda whose potential is only being realized in the recent years. However, the drug delivery system used for administering the herbal medicine to the patient is traditional and out-of-date, resulting in reduced efficacy of the drug. If the novel drug delivery technology is applied in herbal medicine, it may help in...

  10. Magnetic Properties of Polyvinyl Alcohol and Doxorubicine Loaded Iron Oxide Nanoparticles for Anticancer Drug Delivery Applications.

    Directory of Open Access Journals (Sweden)

    Muhammad Nadeem

    Full Text Available The current study emphasizes the synthesis of iron oxide nanoparticles (IONPs and impact of hydrophilic polymer polyvinyl alcohol (PVA coating concentration as well as anticancer drug doxorubicin (DOX loading on saturation magnetization for target drug delivery applications. Iron oxide nanoparticles particles were synthesized by a reformed version of the co-precipitation method. The coating of polyvinyl alcohol along with doxorubicin loading was carried out by the physical immobilization method. X-ray diffraction confirmed the magnetite (Fe3O4 structure of particles that remained unchanged before and after polyvinyl alcohol coating and drug loading. Microstructure and morphological analysis was carried out by transmission electron microscopy revealing the formation of nanoparticles with an average size of 10 nm with slight variation after coating and drug loading. Transmission electron microscopy, energy dispersive, and Fourier transform infrared spectra further confirmed the conjugation of polymer and doxorubicin with iron oxide nanoparticles. The room temperature superparamagnetic behavior of polymer-coated and drug-loaded magnetite nanoparticles were studied by vibrating sample magnetometer. The variation in saturation magnetization after coating evaluated that a sufficient amount of polyvinyl alcohol would be 3 wt. % regarding the externally controlled movement of IONPs in blood under the influence of applied magnetic field for in-vivo target drug delivery.

  11. Doxorubicin-loaded PLA/pearl electrospun nanofibrous scaffold for drug delivery and tumor cell treatment

    Science.gov (United States)

    Dai, Jiamu; Jin, Junhong; Yang, Shenglin; Li, Guang

    2017-07-01

    A drug-loaded implantable scaffold is a promising substitute for the treatment of tissue defects after a tumor resection operation. In this work, natural pearl powder with good biocompatibility and osteoconductivity was incorporated into polylactic (PLA) nanofibers via electrospinning, and doxorubicin hydrochloride (DOX) was also loaded in the PLA/pearl scaffold, resulting in a drug-loaded composite nanofibrous scaffold (DOX@PLA/pearl). In vitro drug delivery of DOX from a PLA/pearl composite scaffold was measured and in vitro anti-tumor efficacy was also examined, in particular the effect of the pearl content on both key properties were studied. The results showed that DOX was successfully loaded into PLA/pearl composite nanofibrous scaffolds with different pearl content. More importantly, the delivery rate of DOX kept rising as the pearl content increased, and the anti-tumor efficacy of the drug-loaded scaffold on HeLa cells was improved at an appropriate pearl powder concentration. Thus, we expect that the prepared DOX@PLA/pearl powder nanofibrous mat is a highly promising implantable scaffold that has great potential in postoperative cancer treatment.

  12. Modeling of Generic Slung Load System

    DEFF Research Database (Denmark)

    Bisgaard, Morten; Bendtsen, Jan Dimon; la Cour-Harbo, Anders

    2009-01-01

    This paper presents the result of the modelling and verification of a generic slung load system using a small-scale helicopter. The model is intended for use in simulation, pilot training, estimation, and control. The model is derived using a redundant coordinate formulation based on Gauss......' Principle of Least Constraint using the Udwadia-Kalaba equation and can be used to model all body to body slung load suspension types. The model provides intuitive and easy-to-use means of modelling and simulating different slung load suspension types. It includes detection of, and response to, wire...... slackening and tightening as well as aerodynamic coupling between the helicopter and the load. Furthermore, it is shown how the model can be easily used for multi-lift systems either with multiple helicopters or multiple loads. A numerical stabilisation algorithm is introduced and finally the use...

  13. Drug delivery application of extracellular vesicles; insight into production, drug loading, targeting, and pharmacokinetics

    Directory of Open Access Journals (Sweden)

    Masaharu Somiya

    2017-01-01

    Full Text Available Extracellular vesicles (EVs are secreted from any types of cells and shuttle between donor cells and recipient cells. Since EVs deliver their cargos such as proteins, nucleic acids, and other molecules for intercellular communication, they are considered as novel mode of drug delivery vesicles. EVs possess advantages such as inherent targeting ability and non-toxicity over conventional nanocarriers. Much efforts have so far been made for the application of EVs as a drug delivery carrier, however, basic techniques, such as mass-scale production, drug loading, and engineering of EVs are still limited. In this review, we summarize following four points. First, recent progress on the production method for EVs is described. Second, current techniques of drug loading methods are summarized. Third, targeting approach to specifically deliver cargo molecules for diseased sites by engineered EVs is discussed. Lastly, strategies to control pharmacokinetics and improve biodistribution are discussed.

  14. G2 Autonomous Control for Cryogenic Delivery Systems

    Science.gov (United States)

    Dito, Scott J.

    2014-01-01

    The Independent System Health Management-Autonomous Control (ISHM-AC) application development for cryogenic delivery systems is intended to create an expert system that will require minimal operator involvement and ultimately allow for complete autonomy when fueling a space vehicle in the time prior to launch. The G2-Autonomous Control project is the development of a model, simulation, and ultimately a working application that will control and monitor the cryogenic fluid delivery to a rocket for testing purposes. To develop this application, the project is using the programming language/environment Gensym G2. The environment is an all-inclusive application that allows development, testing, modeling, and finally operation of the unique application through graphical and programmatic methods. We have learned G2 through training classes and subsequent application development, and are now in the process of building the application that will soon be used to test on cryogenic loading equipment here at the Kennedy Space Center Cryogenics Test Laboratory (CTL). The G2 ISHM-AC application will bring with it a safer and more efficient propellant loading system for the future launches at Kennedy Space Center and eventually mobile launches from all over the world.

  15. A novel approach to oral iron delivery using ferrous sulphate loaded solid lipid nanoparticles.

    Science.gov (United States)

    Zariwala, M Gulrez; Elsaid, Naba; Jackson, Timothy L; Corral López, Francisco; Farnaud, Sebastien; Somavarapu, Satyanarayana; Renshaw, Derek

    2013-11-18

    Iron (Fe) loaded solid lipid nanoparticles (SLN's) were formulated using stearic acid and iron absorption was evaluated in vitro using the cell line Caco-2 with intracellular ferritin formation as a marker of iron absorption. Iron loading was optimised at 1% Fe (w/w) lipid since an inverse relation was observed between initial iron concentration and SLN iron incorporation efficiency. Chitosan (Chi) was included to prepare chitosan coated SLN's. Particle size analysis revealed a sub-micron size range (300.3±31.75 nm to 495.1±80.42 nm), with chitosan containing particles having the largest dimensions. As expected, chitosan (0.1%, 0.2% and 0.4% w/v) conferred a net positive charge on the particle surface in a concentration dependent manner. For iron absorption experiments equal doses of Fe (20 μM) from selected formulations (SLN-FeA and SLN-Fe-ChiB) were added to Caco-2 cells and intracellular ferritin protein concentrations determined. Caco-2 iron absorption from SLN-FeA (583.98±40.83 ng/mg cell protein) and chitosan containing SLN-Fe-ChiB (642.77±29.37 ng/mg cell protein) were 13.42% and 24.9% greater than that from ferrous sulphate (FeSO4) reference (514.66±20.43 ng/mg cell protein) (p≤0.05). We demonstrate for the first time preparation, characterisation and superior iron absorption in vitro from SLN's, suggesting the potential of these formulations as a novel system for oral iron delivery. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Liposomal drug delivery systems--clinical applications.

    Science.gov (United States)

    Goyal, Parveen; Goyal, Kumud; Vijaya Kumar, Sengodan Gurusamy; Singh, Ajit; Katare, Om Prakash; Mishra, Dina Nath

    2005-03-01

    Liposomes have been widely investigated since 1970 as drug carriers for improving the delivery of therapeutic agents to specific sites in the body. As a result, numerous improvements have been made, thus making this technology potentially useful for the treatment of certain diseases in the clinics. The success of liposomes as drug carriers has been reflected in a number of liposome-based formulations, which are commercially available or are currently undergoing clinical trials. The current pharmaceutical preparations of liposome-based therapeutic systems mainly result from our understanding of lipid-drug interactions and liposome disposition mechanisms. The insight gained from clinical use of liposome drug delivery systems can now be integrated to design liposomes that can be targeted on tissues, cells or intracellular compartments with or without expression of target recognition molecules on liposome membranes. This review is mainly focused on the diseases that have attracted most attention with respect to liposomal drug delivery and have therefore yielded most progress, namely cancer, antibacterial and antifungal disorders. In addition, increased gene transfer efficiencies could be obtained by appropriate selection of the gene transfer vector and mode of delivery.

  17. Hydrogen storage and delivery system development: Fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Handrock, J.L.; Malinowski, M.E.; Wally, K. [Sandia National Lab., Livermore, CA (United States)

    1996-10-01

    Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. This project is part of the Field Work Proposal entitled Hydrogen Utilization in Internal Combustion Engines (ICE). The goal of the Hydrogen Storage and Delivery System Development Project is to expand the state-of-the-art of hydrogen storage and delivery system design and development. At the foundation of this activity is the development of both analytical and experimental evaluation platforms. These tools provide the basis for an integrated approach for coupling hydrogen storage and delivery technology to the operating characteristics of potential hydrogen energy use applications. Analytical models have been developed for internal combustion engine (ICE) hybrid and fuel cell driven vehicles. The dependence of hydride storage system weight and energy use efficiency on engine brake efficiency and exhaust temperature for ICE hybrid vehicle applications is examined. Results show that while storage system weight decreases with increasing engine brake efficiency energy use efficiency remains relatively unchanged. The development, capability, and use of a newly developed fuel cell vehicle hydride storage system model will also be discussed. As an example of model use power distribution and control for a simulated driving cycle is presented. An experimental test facility, the Hydride Bed Testing Laboratory (HBTL) has been designed and fabricated. The development of this facility and its use in storage system development will be reviewed. These two capabilities (analytical and experimental) form the basis of an integrated approach to storage system design and development. The initial focus of these activities has been on hydride utilization for vehicular applications.

  18. Bromocriptine loaded chitosan nanoparticles intended for direct nose to brain delivery: pharmacodynamic, pharmacokinetic and scintigraphy study in mice model.

    Science.gov (United States)

    Md, Shadab; Khan, Rashid A; Mustafa, Gulam; Chuttani, Krishna; Baboota, Sanjula; Sahni, Jasjeet K; Ali, Javed

    2013-02-14

    The primary aim of this study was to investigate the potential use of chitosan nanoparticles as a delivery system to enhance the brain targeting efficiency of bromocriptine (BRC) following intranasal (i.n.) administration. The BRC loaded chitosan nanoparticles (CS NPs) were prepared by ionic gelation of CS with tripolyphosphate anions. These NPs had a mean size (161.3 ± 4. 7 nm), zeta potential (+40.3 ± 2.7 mV), loading capacity (37.8% ± 1.8%) and entrapment efficiency (84.2% ± 3.5%). The oral administration of haloperidol (2mg/kg) to mice produced typical Parkinson (PD) symptoms. Catalepsy and akinesia outcomes in animals receiving BRC either in solution or within CS NPs showed a reversal in catalepsy and akinesia behavior when compared to haloperidol treated mice, this reversal being specially pronounced in mice receiving BRC loaded CS NPs. Biodistribution of BRC formulations in the brain and blood of mice following i.n. and intravenous (i.v.) administration was performed using optimized technetium labeled (99mTc-labeled) BRC formulations. The brain/blood ratio of 0.47 ± 0.04, 0.69 ± 0.031, and 0.05 ± 0.01 for BRC solution (i.n.), BRC loaded CS NPs (i.n.) and (i.v.) respectively, at 0.5h are suggestive of direct nose to brain transport bypassing the blood-brain barrier. Gamma scintigraphy imaging of mice brain following i.v. and i.n. administrations were performed to determine the localization of drug in brain. The drug targeting index and direct transport percentage for BRC loaded CS NPs following i.n. route were 6.3 ± 0.8 and 84.2% ± 1.9%. These encouraging results confirmed the development of a novel non-invasive nose to brain delivery system of BRC for the treatment of PD.

  19. Load Transfer Mechanisms in Anchored Geosynthetic Systems

    Science.gov (United States)

    1990-12-20

    TITLE (Include Security Classitcation) (U) Load Transfer Mechanisms in Anchored Geosynthetic Systems 12. PERSONAL AUTHOR(S) Hrvciw, Roman D. 13a... Geosynthetics 19. ABSTRACT (Continue on reverse it necessary and identity by block number) The success of an anchored geosynthetic system (AGS) depends on...the satisfactory transfer of load between the surface-deployed geosynthetic and anchors (typically ribbed reinforcing rods) driven into the slope

  20. Bioinspired silica as drug delivery systems and their biocompatibility

    DEFF Research Database (Denmark)

    Steven, Christopher R.; Busby, Grahame A.; Mather, Craig

    2014-01-01

    Silica nanoparticles have been shown to have great potential as drug delivery systems (DDS), however, their fabrication often involves harsh chemicals and energy intensive laborious methods. This work details the employment of a bioinspired "green" method for the controlled synthesis of silica, use...... allowing a one step and one pot method for simultaneous silica synthesis and drug loading. We established that the drug release profile can be modulated by synthetic parameters, which can allow design of tailored DDS. A systematic investigation using a two level factorial design was adopted in order...... of the products to entrap and release drug molecules and their cytotoxicity in order to develop novel DDS. Bioinspired silica synthesis occurs at pH 7, room temperature and in less than 5 minutes, resulting in a rapid, cheaper and greener route. Drugs were loaded into silica during the silica formation, thus...

  1. Hydrogen storage and delivery system development: Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Handrock, J.L. [Sandia National Labs., Livermore, CA (United States)

    1996-10-01

    Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. This project is part of the Field Work Proposal entitled Hydrogen Utilization in Internal Combustion Engines (ICE). The goal of the Hydrogen Storage and Delivery System Development Project is to expand the state-of-the-art of hydrogen storage and delivery system design and development. At the foundation of this activity is the development of both analytical and experimental evaluation platforms. These tools provide the basis for an integrated approach for coupling hydrogen storage and delivery technology to the operating characteristics of potential hydrogen energy use applications. Results of the analytical model development portion of this project will be discussed. Analytical models have been developed for internal combustion engine (ICE) hybrid and fuel cell driven vehicles. The dependence of hydride storage system weight and energy use efficiency on engine brake efficiency and exhaust temperature for ICE hybrid vehicle applications is examined. Results show that while storage system weight decreases with increasing engine brake efficiency energy use efficiency remains relatively unchanged. The development, capability, and use of a recently developed fuel cell vehicle storage system model will also be discussed. As an example of model use, power distribution and control for a simulated driving cycle is presented. Model calibration results of fuel cell fluid inlet and exit temperatures at various fuel cell idle speeds, assumed fuel cell heat capacities, and ambient temperatures are presented. The model predicts general increases in temperature with fuel cell power and differences between inlet and exit temperatures, but under predicts absolute temperature values, especially at higher power levels.

  2. Investigation of rotor control system loads

    Institute of Scientific and Technical Information of China (English)

    Sun Tao; Tan Jianfeng; Wang Haowen

    2013-01-01

    This paper concentrates on the aeroelasticity analysis of rotor blade and rotor control systems. A new multi-body dynamics model is established to predict both rotor pitch link loads and swashplate servo loads. Two helicopter rotors of UH-60A and SA349/2, both operating in two critical flight conditions, high-speed flight and high-thrust flight, are studied. The analysis shows good agreements with the flight test data and the calculation results using CAMRAD II. The mechanisms of rotor control loads are then analyzed in details based on the present predictions and the flight test data. In high-speed conditions, the pitch link loads are dominated by the integral of blade pitching moments, which are generated by cyclic pitch control. In high-thrust conditions, the positive pitching loads in the advancing side are caused by high collective pitch angle, and dynamic stall in the retreating side excites high-frequency responses. The swashplate servo loads are predominated by the rotor pitch link loads, and the inertia of the swashplate has significant effects on high-frequency harmonics of the servo loads.

  3. Ultrasound-guided delivery of microRNA loaded nanoparticles into cancer.

    Science.gov (United States)

    Wang, Tzu-Yin; Choe, Jung Woo; Pu, Kanyi; Devulapally, Rammohan; Bachawal, Sunitha; Machtaler, Steven; Chowdhury, Sayan Mullick; Luong, Richard; Tian, Lu; Khuri-Yakub, Butrus; Rao, Jianghong; Paulmurugan, Ramasamy; Willmann, Jürgen K

    2015-04-10

    Ultrasound induced microbubble cavitation can cause enhanced permeability across natural barriers of tumors such as vessel walls or cellular membranes, allowing for enhanced therapeutic delivery into the target tissues. While enhanced delivery of small (100nm) therapeutic carriers into cancer remains unclear and may require a higher pressure for sufficient delivery. Enhanced delivery of larger therapeutic carriers such as FDA approved pegylated poly(lactic-co-glycolic acid) nanoparticles (PLGA-PEG-NP) has significant clinical value because these nanoparticles have been shown to protect encapsulated drugs from degradation in the blood circulation and allow for slow and prolonged release of encapsulated drugs at the target location. In this study, various acoustic parameters were investigated to facilitate the successful delivery of two nanocarriers, a fluorescent semiconducting polymer model drug nanoparticle as well as PLGA-PEG-NP into human colon cancer xenografts in mice. We first measured the cavitation dose produced by various acoustic parameters (pressure, pulse length, and pulse repetition frequency) and microbubble concentration in a tissue mimicking phantom. Next, in vivo studies were performed to evaluate the penetration depth of nanocarriers using various acoustic pressures, ranging between 1.7 and 6.9MPa. Finally, a therapeutic microRNA, miR-122, was loaded into PLGA-PEG-NP and the amount of delivered miR-122 was assessed using quantitative RT-PCR. Our results show that acoustic pressures had the strongest effect on cavitation. An increase of the pressure from 0.8 to 6.9MPa resulted in a nearly 50-fold increase in cavitation in phantom experiments. In vivo, as the pressures increased from 1.7 to 6.9MPa, the amount of nanoparticles deposited in cancer xenografts was increased from 4- to 14-fold, and the median penetration depth of extravasated nanoparticles was increased from 1.3-fold to 3-fold, compared to control conditions without ultrasound, as

  4. Characterisation of zinc delivery from a nipple shield delivery system using a breastfeeding simulation apparatus

    Science.gov (United States)

    Bruggraber, Sylvaine F. A.; Gerrard, Stephen E.; Kendall, Richard A.; Tuleu, Catherine; Slater, Nigel K. H.

    2017-01-01

    Zinc delivery from a nipple shield delivery system (NSDS), a novel platform for administering medicines to infants during breastfeeding, was characterised using a breastfeeding simulation apparatus. In this study, human milk at flow rates and pressures physiologically representative of breastfeeding passed through the NSDS loaded with zinc-containing rapidly disintegrating tablets, resulting in release of zinc into the milk. Inductively coupled plasma optical emission spectrometry was used to detect the zinc released, using a method that does not require prior digestion of the samples and that could be applied in other zinc analysis studies in breast milk. Four different types of zinc-containing tablets with equal zinc load but varying excipient compositions were tested in the NSDS in vitro. Zinc release measured over 20 minutes ranged from 32–51% of the loaded dose. Total zinc release for sets tablets of the same composition but differing hardness were not significantly different from one another with P = 0.3598 and P = 0.1270 for two tested pairs using unpaired t tests with Welch’s correction. By the same test total zinc release from two sets of tablets having similar hardness but differing composition were also not significantly significant with P = 0.2634. Future zinc tablet composition and formulation optimisation could lead to zinc supplements and therapeutics with faster drug release, which could be administered with the NSDS during breastfeeding. The use of the NSDS to deliver zinc could then lead to treatment and prevention of some of the leading causes of child mortality, including diarrheal disease and pneumonia. PMID:28158283

  5. Characterisation of zinc delivery from a nipple shield delivery system using a breastfeeding simulation apparatus.

    Science.gov (United States)

    Scheuerle, Rebekah L; Bruggraber, Sylvaine F A; Gerrard, Stephen E; Kendall, Richard A; Tuleu, Catherine; Slater, Nigel K H

    2017-01-01

    Zinc delivery from a nipple shield delivery system (NSDS), a novel platform for administering medicines to infants during breastfeeding, was characterised using a breastfeeding simulation apparatus. In this study, human milk at flow rates and pressures physiologically representative of breastfeeding passed through the NSDS loaded with zinc-containing rapidly disintegrating tablets, resulting in release of zinc into the milk. Inductively coupled plasma optical emission spectrometry was used to detect the zinc released, using a method that does not require prior digestion of the samples and that could be applied in other zinc analysis studies in breast milk. Four different types of zinc-containing tablets with equal zinc load but varying excipient compositions were tested in the NSDS in vitro. Zinc release measured over 20 minutes ranged from 32-51% of the loaded dose. Total zinc release for sets tablets of the same composition but differing hardness were not significantly different from one another with P = 0.3598 and P = 0.1270 for two tested pairs using unpaired t tests with Welch's correction. By the same test total zinc release from two sets of tablets having similar hardness but differing composition were also not significantly significant with P = 0.2634. Future zinc tablet composition and formulation optimisation could lead to zinc supplements and therapeutics with faster drug release, which could be administered with the NSDS during breastfeeding. The use of the NSDS to deliver zinc could then lead to treatment and prevention of some of the leading causes of child mortality, including diarrheal disease and pneumonia.

  6. Chitosan magnetic nanoparticles for drug delivery systems.

    Science.gov (United States)

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

    2016-06-01

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

  7. Recent Advances in Ocular Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Shinobu Fujii

    2011-01-01

    Full Text Available Transport of drugs applied by traditional dosage forms is restricted to the eye, and therapeutic drug concentrations in the target tissues are not maintained for a long duration since the eyes are protected by a unique anatomy and physiology. For the treatment of the anterior segment of the eye, various droppable products to prolong the retention time on the ocular surface have been introduced in the market. On the other hand, direct intravitreal implants, using biodegradable or non-biodegradable polymer technology, have been widely investigated for the treatment of chronic vitreoretinal diseases. There is urgent need to develop ocular drug delivery systems which provide controlled release for the treatment of chronic diseases, and increase patient’s and doctor’s convenience to reduce the dosing frequency and invasive treatment. In this article, progress of ocular drug delivery systems under clinical trials and in late experimental stage is reviewed.

  8. ORGANOGELS: ADVANCED AND NOVEL DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Garg Tarun

    2011-12-01

    Full Text Available Organogel, is a non crystalline, non-glassy thermoreversible (thermoplastic solid material and viscoelastic system, can be regarded as a semi-solid preparation which has an immobilized external apolar phase. The apolar phase gets immobilized within spaces of the three-dimensional networked structure formed due to the physical interactions amongst the self assembled structures of compounds regarded as gelators. Often, these systems are based on self-assembly of the structurant molecules. In general, organogels are thermodynamically stable in nature and have been explored as matrices for the delivery of bioactive agents. Organogels have potential for use in a number of applications, such as in pharmaceuticals, cosmetics, art conservation, and food. An example of formation of an undesired thermoreversible network is the occurrence of wax crystallization in petroleum. In the current manuscript, attempts have been made to understand the properties of organogels, various types of organogelators and some applications of the organogels in controlled delivery.

  9. Construction of paclitaxel-loaded poly (2-hydroxyethyl methacrylate-g-poly (lactide- 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine copolymer nanoparticle delivery system and evaluation of its anticancer activity

    Directory of Open Access Journals (Sweden)

    Liang XJ

    2012-03-01

    Full Text Available Xiaowei Ma*, Huan Wang*, Shubin Jin, Yan Wu, Xing-Jie LiangLaboratory of Nanomedicine and Nanosafety, Division of Nanomedicine and Nanobiology, National Center for Nanoscience and Technology, People’s Republic of China; and CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Chinese Academy of Sciences, Beijing, People’s Republic of China *These authors contributed equally to this workBackground: There is an urgent need to develop drug-loaded biocompatible nanoscale packages with improved therapeutic efficacy for effective clinical treatment. To address this need, a novel poly (2-hydroxyethyl methacrylate-poly (lactide-1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine [PHEMA-g-(PLA-DPPE] copolymer was designed and synthesized to enable these nanoparticles to be pH responsive under pathological conditions.Methods: The structural properties and thermal stability of the copolymer was measured and confirmed by Fourier transform infrare d spectroscopy, nuclear magnetic resonance, and thermogravimetric analysis. In order to evaluate its feasibility as a drug carrier, paclitaxel-loaded PHEMA-g-(PLA-DPPE nanoparticles were prepared using the emulsion-solvent evaporation method.Results: The PHEMA-g-(PLA-DPPE nanoparticles could be efficiently loaded with paclitaxel and controlled to release the drug gradually and effectively. In vitro release experiments demonstrated that drug release was faster at pH 5.0 than at pH 7.4. The anticancer activity of the PHEMA-g-(PLA-DPPE nanoparticles was measured in breast cancer MCF-7 cells in vivo and in vitro. In comparison with the free drug, the paclitaxel-loaded PHEMA-g-(PLA-DPPE nanoparticles could induce more significant tumor regression.Conclusion: This study indicates that PHEMA-g-(PLA-DPPE nanoparticles are promising carriers for hydrophobic drugs. This system can passively target cancer tissue and release drugs in a controllable manner, as determined by the pH value of the area in

  10. Advanced and controlled drug delivery systems in clinical disease management

    NARCIS (Netherlands)

    Brouwers, JRBJ

    1996-01-01

    Advanced and controlled drug delivery systems are important for clinical disease management. In this review the most important new systems which have reached clinical application are highlighted. Microbiologically controlled drug delivery is important for gastrointestinal diseases like ulcerative co

  11. Hydroxycamptothecin-loaded nanoparticles enhance target drug delivery and anticancer effect

    Directory of Open Access Journals (Sweden)

    Li Su

    2008-05-01

    Full Text Available Abstract Background Hydroxycamptothecin (HCPT has been shown to have activity against a broad spectrum of cancers. In order to enhance its tissue-specific delivery and anticancer activity, we prepared HCPT-loaded nanoparticles made from poly(ethylene glycol-poly(γ-benzyl-L-glutamate (PEG-PBLG, and then studied their release characteristics, pharmacokinetic characteristics, and anticancer effects. PEG-PBLG nanoparticles incorporating HCPT were prepared by a dialysis method. Scanning electron microscopy (SEM was used to observe the shape and diameter of the nanoparticles. The HCPT release characteristics in vitro were evaluated by ultraviolet spectrophotometry. A high-performance liquid chromatography (HPLC detection method for determining HCPT in rabbit plasma was established. The pharmacokinetic parameters of HCPT/PEG-PBLG nanoparticles were compared with those of HCPT. Results The HCPT-loaded nanoparticles had a core-shell spherical structure, with a core diameter of 200 nm and a shell thickness of 30 nm. Drug-loading capacity and drug encapsulation were 7.5 and 56.8%, respectively. The HCPT release profile was biphasic, with an initial abrupt release, followed by sustained release. The terminal elimination half-lives (t 1/2 β of HCPT and HCPT-loaded nanoparticles were 4.5 and 10.1 h, respectively. Peak concentrations (Cmax of HCPT and HCPT-loaded nanoparticles were 2627.8 and 1513.5 μg/L, respectively. The apparent volumes of distribution of the HCPT and HCPT-loaded nanoparticles were 7.3 and 20.0 L, respectively. Compared with a blank control group, Lovo cell xenografts or Tca8113 cell xenografts in HCPT or HCPT-loaded nanoparticle treated groups grew more slowly and the tumor doubling times were increased. The tumor inhibition effect in the HCPT-loaded nanosphere-treated group was significantly higher than that of the HCPT-treated group (p 0.05. Conclusion Compared to the HCPT- and control-treated groups, the HCPT-loaded nanoparticle

  12. Modelling of Generic Slung Load System

    DEFF Research Database (Denmark)

    Bisgaard, Morten; Bendtsen, Jan Dimon; La Cour-Harbo, Anders

    2006-01-01

    of Least Constraint using the Udwadia-Kalaba equation and can be used to model all body to body slung load suspension types. The model gives an intuitive and easy-to-use way of modelling and simulating di erent slung load suspension types and it includes detection and response of wire slacking......This paper presents the result of modelling and verification of a generic slung load system using a small-scale helicopter. The model is intended for use in simulation, pilot training, estimation, and control. The model is derived using a redundant coordinate formulation based on Gauss Principle...

  13. Drug delivery system and breast cancer cells

    Science.gov (United States)

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

    2016-06-01

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

  14. TRANSCUTANEOUS DRUG DELIVERY SYSTEM: A COMPREHENSIVE REVIEW

    Directory of Open Access Journals (Sweden)

    Sandhu Premjeet

    2011-12-01

    Full Text Available Conventional drug delivery systems are often not suitable for new protein based and other Therapeutic compounds produced by modern technology. Therefore an alternative Approach to deliver these drugs can be achieved through the skin in the form of transcutaneous drug delivery system. Modern medicine has responded with the development of methods to deliver drug transcutanously (through the skin for therapeutic use as an alternative to traditional route including oral, intravascular, intramuscular, subcutaneous, and sublingual. Transcutaneous drug delivery has many theoretic and practical advantage and disadvantages, and such issues are often a concern for both clinicians and patients. Transcutaneous patches are flexible pharmaceutical preparations of varying sizes, containing one or more active ingredient, intended to be applied to the unbroken skin in order to deliver the active ingredient to the systemic circulation after passing through the skin barriers. A Transcutaneous patch or skin patch is a medicated adhesive patch that is placed on the skin to deliver a specific dose of medication through the skin and into the bloodstream. Often, this promotes healing to an injured area of the body. In this method, the drug enters the bloodstream directly through skin and it avoid first pass effect. Characterization of Transcutaneous patch are necessary because check it’s quality, size, time of onset & duration, adhesive property, thickness, weight of patch, moisture of content, uniformity & cutaneous toxicological studies. Their requirements for evaluation are HPLC, U.V. spectrophotometer, screw gauge, digital balance, desiccators, thin layer chromatography & K.C. Cell used.

  15. Integrating Autonomous Load Controllers in Power Systems

    DEFF Research Database (Denmark)

    Douglass, Philip James

    violations of voltage constraints. This voltage-sensitive controller can also operate alone, without the frequency-sensitive controller, to provide voltage regulation service and increase load diversity in any distribution network where lower voltage level corresponds to higher load.The frequency......-sensitive and voltage-sensitive autonomous load are viable alternatives to conventional frequency and voltage control devices. When used in combination, they complement each other. In systems where the operator has centrally dispatchable resources to regulate frequency, these resources can be used to dispatch otherwise...... autonomous frequency-sensitive loads. Moreover, where centrally dispatchable frequency regulation resources can rapidly change operating points, such as in a micro-grid, the energy sources can be used as transmitters for a ultra-low-bandwidth uni-directional power line communication system....

  16. Microparticulate based topical delivery system of clobetasol propionate.

    Science.gov (United States)

    Badıllı, Ulya; Sen, Tangül; Tarımcı, Nilüfer

    2011-09-01

    Psoriasis is a chronic, autoimmune skin disease affecting approximately 2% of the world's population. Clobetasol propionate which is a superpotent topical corticosteroid is widely used for topical treatment of psoriasis. Conventional dosage forms like creams and ointments are commonly prefered for the therapy. The purpose of this study was to develop a new topical delivery system in order to provide the prolonged release of clobetasol propionate and to reduce systemic absorption and side effects of the drug. Clobetasol propionate loaded-poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres were prepared by oil-in-water emulsion-solvent evaporation technique. Particle size analysis, morphological characterization, DSC and XRD analyses and in vitro drug release studies were performed on the microparticle formulations. Emulgel formulations were prepared as an alternative for topical delivery of clobetasol propionate. In vitro drug release studies were carried out from the emulgel formulations containing pure drug and drug-loaded microspheres. In addition, the same studies were performed to determine the drug release from the commercial cream product of clobetasol propionate. The release of clobetasol propionate from the emulgel formulations was significantly higher than the commercial product. In addition, the encapsulation of clobetasol propionate in the PLGA microspheres significantly delayed the drug release from the emulgel formulation. As a result, the decrease in the side effects of clobetasol propionate by the formulation containing PLGA microspheres is expected.

  17. Future prospects for gene delivery systems.

    Science.gov (United States)

    Kuşcu, Lale; Sezer, Ali Demir

    2017-10-01

    Gene therapy is the challenging area of biotechnology. Despite its promise for critical diseases, it has serious safety and efficiency issues, particularly with regards to gene transfer systems. Areas covered: We examined the current situation with gene transfer systems and addressed problems this technology. We then searched patent applications about in the area from the Patentscope online system, the international patent database. We analyzed the data obtained to get a general idea about gene delivery systems designed for future use and assessed approaches for more efficient, safer and valid delivery systems. Expert opinion: When quality assurance terms are fulfilled, some of these issues (genetic changes, mutations) could be minimized during the production process. Modification of vectors for improving their efficiency and safety or development of alternative transfer systems could be the solutions for these problems. Gene transfer technologies are important for gene therapy and should demonstrate effective, target-specific and acceptable safety profiles. For this reason, searching for alternatives to current systems is a necessity.

  18. Transdermal drug delivery system: An overview

    Directory of Open Access Journals (Sweden)

    Vaibhav Rastogi

    2012-01-01

    Full Text Available Transdermal drug delivery system (TDDS is one of the systems lying under the category of controlled drug delivery, in which the aim is to deliver the drug through the skin in a predetermined and controlled rate. It has various advantages, like prolonged therapeutic effect, reduced side-effects, improved bioavailability, better patient compliance and easy termination of drug therapy. The stratum corneum is considered as the rate limiting barrier in transdermal permeation of most molecules. There are three main routes of drug penetration, which include the appendageal, transcellular and intercellular routes. Skin age, condition, physicochemical factors and environmental factors are some factors that are to be considered while delivering drug through this route. Basic components of TDDS include polymer matrix, membrane, drug, penetration enhancers, pressure-sensitive adhesives, backing laminates, release liner, etc. Transdermal patches can be divided into various systems like reservoir system, matrix system and micro-reservoir system, which are used to incorporate the active ingredients into the circulatory system via the skin. After preparation of transdermal patches, consistent methodology are adopted to test the adhesion properties, physicochemical properties, in vitro drug release studies, in vitro skin permeation studies, skin irritation studies and stability studies. According to the duration of therapy, various drugs are commercially available in the form of transdermal patches.

  19. 42 CFR 457.490 - Delivery and utilization control systems.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Delivery and utilization control systems. 457.490... State Plan Requirements: Coverage and Benefits § 457.490 Delivery and utilization control systems. A... control systems. A State must— (a) Describe the methods of delivery of child health assistance...

  20. Ultrasound-mediated nail drug delivery system.

    Science.gov (United States)

    Abadi, Danielle; Zderic, Vesna

    2011-12-01

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

  1. Alginate nanoparticles protect ferrous from oxidation: Potential iron delivery system.

    Science.gov (United States)

    Katuwavila, Nuwanthi P; Perera, A D L C; Dahanayake, Damayanthi; Karunaratne, V; Amaratunga, Gehan A J; Karunaratne, D Nedra

    2016-11-20

    A novel, efficient delivery system for iron (Fe(2+)) was developed using the alginate biopolymer. Iron loaded alginate nanoparticles were synthesized by a controlled ionic gelation method and was characterized with respect to particle size, zeta potential, morphology and encapsulation efficiency. Successful loading was confirmed with Fourier Transform Infrared spectroscopy and Thermogravimetric Analysis. Electron energy loss spectroscopy study corroborated the loading of ferrous into the alginate nanoparticles. Iron encapsulation (70%) was optimized at 0.06% Fe (w/v) leading to the formation of iron loaded alginate nanoparticles with a size range of 15-30nm and with a negative zeta potential (-38mV). The in vitro release studies showed a prolonged release profile for 96h. Release of iron was around 65-70% at pH of 6 and 7.4 whereas it was less than 20% at pH 2.The initial burst release upto 8h followed zero order kinetics at all three pH values. All the release profiles beyond 8h best fitted the Korsmeyer-Peppas model of diffusion. Non Fickian diffusion was observed at pH 6 and 7.4 while at pH 2 Fickian diffusion was observed. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Recent Trends of Polymer Mediated Liposomal Gene Delivery System

    Directory of Open Access Journals (Sweden)

    Shyamal Kumar Kundu

    2014-01-01

    Full Text Available Advancement in the gene delivery system have resulted in clinical successes in gene therapy for patients with several genetic diseases, such as immunodeficiency diseases, X-linked adrenoleukodystrophy (X-ALD blindness, thalassemia, and many more. Among various delivery systems, liposomal mediated gene delivery route is offering great promises for gene therapy. This review is an attempt to depict a portrait about the polymer based liposomal gene delivery systems and their future applications. Herein, we have discussed in detail the characteristics of liposome, importance of polymer for liposome formulation, gene delivery, and future direction of liposome based gene delivery as a whole.

  3. Hyaluronidase enzyme core-5-fluorouracil-loaded chitosan-PEG-gelatin polymer nanocomposites as targeted and controlled drug delivery vehicles.

    Science.gov (United States)

    Rajan, M; Raj, V; Al-Arfaj, Abdullah A; Murugan, A M

    2013-09-10

    This study examines the performance of novel hyaluronidase enzyme core-5-fluorouracil-loaded chitosan-polyethylene glycol-gelatin polymer nanocomposites, which were prepared using an ionic gelation technique, as targeted and controlled drug delivery vehicles. These hyaluronidase-loaded nanoparticles have recently been proposed as targeted and controlled drug delivery vehicle systems to tissues due to their ability to loosen the intercellular connective matrix of hyaluronic acid. The encapsulation efficiency and loading capacities of the nanoparticles demonstrated that these nanocomposites displayed sufficient binding ability, which depends on the pH and initial concentration of the drug. The cytotoxic effects of the chitosan-hyaluronidase-5-fluorouracil (CS-HYL-5-FU), chitosan-hyaluronidase-5-fluorouracil polyethylene glycol (CS-HYL-5-FU-PEG), and chitosan-hyaluronidase-5-fluorouracil polyethylene glycol-gelatin (CS-HYL-5-FU-PEG-G) nanoparticles were assessed using MTT assays, and the nanovectors were found to be less cytotoxic than the chemotherapeutic 5-FU after incubation for 3-12h. The particle sizes of the CS-HYL-5-FU, CS-HYL-5-FU-PEG and CS-HYL-5-FU-PEG-G polymer composites were between 300 and 580 nm, as determined by a Zetasizer. Scanning electron microscopy (SEM) analysis indicated that the nanocomposites exhibit a clear, smooth surface and fine morphology. Linkages of the polymers, enzyme, and drug were confirmed by FTIR spectroscopy. Atomic fluorescence microscopy (AFM) analysis confirmed the size of the polymer composite nanoparticles. Therefore, this work established that the drug can be successfully encapsulated in chitosan-polyethylene glycol-gelatin-accompanied hyaluronidase nanoparticles with a homogeneous distribution. These nanoparticles can be potential carriers for targeted and controlled drug delivery to cancer cells.

  4. Hypoxia Responsive Drug Delivery Systems in Tumor Therapy.

    Science.gov (United States)

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

    2016-01-01

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

  5. Do English Listening Outcome and Cognitive Load Change for Different Media Delivery Modes in U-Learning?

    Science.gov (United States)

    Chang, Chi-Cheng; Lei, Hao; Tseng, Ju-Shih

    2014-01-01

    Although ubiquitous learning enhances students' access to learning materials, it is crucial to find out which media delivery modes produce the best results for English listening comprehension. The present study examined the effect of media delivery mode (sound and text vs. sound) on English listening comprehension and cognitive load. Participants…

  6. Advanced drug delivery systems: Nanotechnology of health design A review

    Directory of Open Access Journals (Sweden)

    Javad Safari

    2014-04-01

    Full Text Available Nanotechnology has finally and firmly entered the realm of drug delivery. Performances of intelligent drug delivery systems are continuously improved with the purpose to maximize therapeutic activity and to minimize undesirable side-effects. This review describes the advanced drug delivery systems based on micelles, polymeric nanoparticles, and dendrimers. Polymeric carbon nanotubes and many others demonstrate a broad variety of useful properties. This review emphasizes the main requirements for developing new nanotech-nology-based drug delivery systems.

  7. Microfluidic synthesis of dye-loaded polycaprolactone-block-poly(ethylene oxide) nanoparticles: Insights into flow-directed loading and in vitro release for drug delivery.

    Science.gov (United States)

    Bains, Aman; Wulff, Jeremy E; Moffitt, Matthew G

    2016-08-01

    Using the fluorescent probe dye 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) as a surrogate for hydrophobic drugs, we investigate the effects of water content and on-chip flow rate on the multiscale structure, loading and release properties of DiI-loaded poly(ε-caprolactone)-block-poly(ethylene oxide) (PCL-b-PEO) nanoparticles produced in a gas-liquid segmented microfluidic device. We find a linear increase in PCL crystallinity within the nanoparticle cores with increasing flow rate, while mean nanoparticle sizes first decrease and then increase with flow rate coincident with the disappearance and reappearance of long filament nanoparticles. Loading efficiencies at the lower water content (cwc+10wt%) are generally higher (up to 94%) compared to loading efficiencies (up to 53%) at the higher water content (cwc+75wt%). In vitro release times range between ∼2 and 4days for nanoparticles produced at cwc+10wt% and >15days for nanoparticles produced at cwc+75wt%. At the lower water content, slower release of DiI is found for nanoparticles produced at higher flow rate, while at high water content, release times first decrease and then increase with flow rate. Finally, we investigate the effects of the chemical and physical characteristics of the release medium on the kinetics of in vitro DiI release and nanoparticle degradation. This work demonstrates the general utility of dye-loaded nanoparticles as model systems for screening chemical and flow conditions for producing drug delivery formulations within microfluidic devices.

  8. Modular load flow for restructured power systems

    CERN Document Server

    Hariharan, M V; Gupta, Pragati P

    2016-01-01

    In the subject of power systems, authors felt that a re-look is necessary at some conventional methods of analysis. In this book, the authors have subjected the time-honoured load flow to a close scrutiny. Authors have discovered and discussed a new load flow procedure – Modular Load Flow. Modular Load Flow explores use of power – a scalar – as source for electrical circuits which are conventionally analysed by means of phasors – the ac voltages or currents. The method embeds Kirchhoff’s circuit laws as topological property into its scalar equations and results in a unique wonderland where phase angles do not exist! Generators are shown to have their own worlds which can be superimposed to obtain the state of the composite power system. The treatment is useful in restructured power systems where stakeholders and the system operators may desire to know individual generator contributions in line flows and line losses for commercial reasons. Solution in Modular Load Flow consists of explicit expression...

  9. Common source-multiple load vs. separate source-individual load photovoltaic system

    Science.gov (United States)

    Appelbaum, Joseph

    1989-01-01

    A comparison of system performance is made for two possible system setups: (1) individual loads powered by separate solar cell sources; and (2) multiple loads powered by a common solar cell source. A proof for resistive loads is given that shows the advantage of a common source over a separate source photovoltaic system for a large range of loads. For identical loads, both systems perform the same.

  10. Microbubbles coupled to methotrexate-loaded liposomes for ultrasound-mediated delivery of methotrexate across the blood-brain barrier.

    Science.gov (United States)

    Wang, Xiang; Liu, Ping; Yang, Weixiao; Li, Lu; Li, Peijing; Liu, Zheng; Zhuo, Zhongxiong; Gao, Yunhua

    2014-01-01

    Methotrexate (MTX) is the single most effective agent for the treatment of primary central nervous system lymphoma. Currently, the delivery of MTX to the brain is achieved by high systemic doses, which cause severe long-term neurotoxicity, or intrathecal administration, which is highly invasive and may lead to infections or hemorrhagic complications. Acoustically active microbubbles have been developed as drug carriers for the noninvasive and brain-targeted delivery of therapeutics. However, their application is limited by their low drug-loading capacity. To overcome this limitation, we prepared microbubbles coupled to MTX-loaded liposomes using ZHIFUXIAN, a novel type of microbubbles with a superior safety profile and long circulation time. MTX-liposome-coupled microbubbles had a high drug-loading capacity of 8.91%± 0.86%, and their size (2.64 ± 0.93 μm in diameter) was suitable for intravenous injection. When used with ultrasound, they showed more potent in vitro cytotoxicity against Walker-256 cancer cells than MTX alone or MTX-loaded liposomes. When Sprague-Dawley rats were exposed to sonication, administration of these MTX-liposome-coupled microbubbles via the tail vein led to targeted disruption of the blood-brain barrier without noticeable tissue or capillary damage. High-performance liquid chromatography analysis of the brain MTX concentration showed that MTX delivery to the brain followed the order of MTX-liposome-coupled microbubbles + ultrasound (25.3 ± 2.4 μg/g) > unmodified ZHIFUXIAN + MTX + ultrasound (18.6 ± 2.2 μg/g) > MTX alone (6.97 ± 0.75 μg/g) > MTX-liposome-coupled microbubbles (2.92 ± 0.39 μg/g). Therefore, treatment with MTX-liposome-coupled microbubbles and ultrasound resulted in a significantly higher brain MTX concentration than all other treatments (Pliposome-coupled microbubbles may hold great promise as new and effective therapies for primary central nervous system lymphoma and other central nervous system malignancies.

  11. GLIMPS sensor and taggant delivery systems

    Science.gov (United States)

    Nunan, Scott C.; Coakley, Peter G.; Niederhaus, Gregory A.; Lum, Chris

    2001-02-01

    A system has been developed for delivering and attaching a sensor payload to a target using a standard 40-mm grenade launcher. The GLIMPS projectile is intended to be a general purpose delivery system for a variety of sensor payloads including visual, acoustic, and chemical sensors. The GLIMPS projectile flight characteristics are similar to existing 40-mm rounds, with a useful range of up to 300 m. The projectile incorporates an attachment mechanism, a shock mitigation system, a power source, and a telemetry system for transmission of sensor data at up to 1/4 mile range. A second design is also being considered. It is a small taggant projectile that uses an adhesive to attach a tracking transmitter or other small payload to a vehicle at up to 50 m range. While initially developed as a military system, both projectiles can be used to enhance law enforcement operations.

  12. A Review: Transdermal Drug Delivery System: A Tool For Novel Drug Delivery System

    Directory of Open Access Journals (Sweden)

    NIKHIL SHARMA

    2011-06-01

    Full Text Available The human skin is a readily accessible surface for drug delivery. Skin of an average adult body covers a surface of approximately 2 m2 and receives about one-third of the blood circulating through the body. Over the past decades, developing controlled drug delivery has become increasingly important in the pharmaceutical industry. The human skin surface is known to contain, on an average, 10- 70 hair follicles and 200-250 sweat ducts on every square centimeters of the skin area. It is one of the most readily accessible organs of the human body. There is considerable interest in the skin as a site of drug application both for local and systemic effect. However, the skin, in particular the stratum corneum, poses a formidable barrier to drug penetration thereby limiting topical and transdermal bioavailability. Skin penetration enhancement techniques have been developed to improve bioavailability and increase the range of drugs for which topical and transdermal delivery is a viable option. During the past decade, the number of drugs formulated in the patches has hardly increased, and there has been little change in the composition of the patch systems. Modifications have been mostly limited to refinements of the materials used. The present review article explores the overall study on transdermal drug delivery system (TDDS which leads to novel drug delivery system (NDDS.

  13. An experimental design approach to the preparation of pegylated polylactide-co-glicolide gentamicin loaded microparticles for local antibiotic delivery

    Energy Technology Data Exchange (ETDEWEB)

    Dorati, Rossella; DeTrizio, Antonella; Genta, Ida; Grisoli, Pietro; Merelli, Alessia [Department of Drug Sciences, Viale Taramelli 12, University of Pavia, 27100, Pavia (Italy); Tomasi, Corrado [IENI CNR Lecco Unit, Via Promessi Sposi 29, 23900, Lecco (Italy); Conti, Bice, E-mail: bice.conti@unipv.it [Department of Drug Sciences, Viale Taramelli 12, University of Pavia, 27100, Pavia (Italy)

    2016-01-01

    The present paper takes into account the DOE application to the preparation process of biodegradable microspheres for osteomyelitis local therapy. With this goal gentamicin loaded polylactide-co-glycolide-co-polyethyleneglycol (PLGA-PEG) microspheres were prepared and investigated. Two preparation protocols (o/w and w/o/w) with different process conditions, and three PLGA-PEG block copolymers with different compositions of lactic and glycolic acids and PEG, were tested. A Design Of Experiment (DOE) screening design was applied as an approach to scale up manufacturing step. The results of DOE screening design confirmed that w/o/w technique, the presence of salt and the 15%w/v polymer concentration positively affected the EE% (72.1–97.5%), and span values of particle size distribution (1.03–1.23), while salt addition alone negatively affected the yield process. Process scale up resulted in a decrease of gentamicin EE% that can be attributed to the high volume of water used to remove PVA and NaCl residues. The results of in vitro gentamicin release study show prolonged gentamicin release up to three months from the microspheres prepared with salt addition in the dispersing phase; the behavior being consistent with their highly compact structure highlighted by scanning electron microscopy analysis. The prolonged release of gentamicin is maintained even after embedding the biodegradable microspheres into a thermosetting composite gel made of chitosan and acellular bovine bone matrix (Orthoss® granules), and the microbiologic evaluation demonstrated the efficacy of the gentamicin loaded microspheres on Escherichia coli. The collected results confirm the feasibility of the scale up of microsphere manufacturing process and the high potential of the microparticulate drug delivery system to be used for the local antibiotic delivery to bone. - Highlights: • To get a more effective therapy for the prevention and treatment of osteomyelitis. • To exploit the local

  14. Liposomes as delivery systems for antineoplastic drugs

    Science.gov (United States)

    Medina, Luis Alberto

    2014-11-01

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

  15. Drug-polymer filled micro-containers for oral delivery loaded using supercritical CO2 aided-impregnation

    DEFF Research Database (Denmark)

    Marizza, Paolo; Keller, Stephan Sylvest; Rades, T.

    2013-01-01

    In this work we present an effective loading technique of micro-containers for oral drug delivery of a poorly water soluble drug in a solid dispersion with polymer. By combining inkjet printing and supercritical CO2 impregnation we load ketoprofen in a solid dispersion with poly...

  16. Load requirements for maintaining structural integrity of Hanford single-shell tanks during waste feed delivery and retrieval activities

    Energy Technology Data Exchange (ETDEWEB)

    JULYK, L.J.

    1999-09-22

    This document provides structural load requirements and their basis for maintaining the structural integrity of the Hanford Single-Shell Tanks during waste feed delivery and retrieval activities. The requirements are based on a review of previous requirements and their basis documents as well as load histories with particular emphasis on the proposed lead transfer feed tanks for the privatized vitrification plant.

  17. Fabrication of a Magnetite Nanoparticle-loaded Polymeric Nanoplatform for Magnetically Guided Drug Delivery

    Institute of Scientific and Technical Information of China (English)

    DING Guo-bin; LIU Hui-ying; WANG Yan; L(U) Yan-yun; WU Yi; GUO Yi; XU Li

    2013-01-01

    We developed a magnetite nanoparticle-loaded polymeric nanoplatform for magnetically guided 10-hydroxycamptothecin(HCPT) delivery.The nanoplatform was fabricated by simultaneously incorporating magnetite nanoparticles(NPs) and HCPT into the polymer micelle self-assembled from methoxy polyethylene glycolpoly(D,L-lactide-co-glycolide)(MPEG-PLGA) copolymer.Successful loading of HCPT into the nanoplatform was confirmed by Fourier transform infrared(FTIR) spectroscopy.Subsequently,we examined the in vitro antitumor efficacy of free HCPT and nanoplatform against three different cancer cell lines——HeLa,A549 and HepG2.Flow cytometric analysis was conducted to reveal the cell apoptosis caused by free HCPT and nanoplatform.Finally,the magnetic targeting property of the nanoplatform was evaluated by a self-designed in vitro experiment.

  18. Mucoadhesive drug delivery system: An overview

    Directory of Open Access Journals (Sweden)

    Bindu M Boddupalli

    2010-01-01

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

  19. [Drug delivery systems for intraocular applications].

    Science.gov (United States)

    Bourges, J-L; Touchard, E; Kowalczuk, L; Berdugo, M; Thomas-Doyle, A; Bochot, A; Gomez, A; Azan, F; Gurny, R; Behar-Cohen, F

    2007-12-01

    Numerous drug delivery systems (DDSs) can be used as intraocular tools to provide a sustained and calibrated release for a specific drug. Great progress has been made on the design, biocompatibility, bioavailability, and efficacy of DDSs. Although several of them are undergoing clinical trials, a few are already on the market and could be of a routine use in clinical practice. Moreover, miniaturization of the implants makes them less and less traumatic for the eye tissues and some DDSs are now able to target certain cells or tissues specifically. An overview of ocular implants with therapeutic application potentials is provided.

  20. Multifunctional non-viral delivery systems based on conjugated polymers.

    Science.gov (United States)

    Yang, Gaomai; Lv, Fengting; Wang, Bing; Liu, Libing; Yang, Qiong; Wang, Shu

    2012-12-01

    Multifunctional nanomaterials with simultaneous therapeutic and imaging functions explore new strategies for the treatment of various diseases. Conjugated polymers (CPs) are considered as novel candidates to serve as multifunctional delivery systems due to their high fluorescence quantum yield, good photostability, and low cytotoxicity. Highly sensitive sensing and imaging properties of CPs are well reviewed, while the applications of CPs as delivery systems are rarely covered. This feature article mainly focuses on CP-based multifunctional non-viral delivery systems for drug, protein, gene, and cell delivery. Promising directions for the further development of CP-based delivery systems are also discussed.

  1. A remotely operated drug delivery system with dose control

    KAUST Repository

    Yi, Ying

    2017-05-08

    “On demand” implantable drug delivery systems can provide optimized treatments, due to their ability to provide targeted, flexible and precise dose release. However, two important issues that need to be carefully considered in a mature device include an effective actuation stimulus and a controllable dose release mechanism. This work focuses on remotely powering an implantable drug delivery system and providing a high degree of control over the released dose. This is accomplished by integration of a resonance-based wireless power transfer system, a constant voltage control circuit and an electrolytic pump. Upon the activation of the wireless power transfer system, the electrolytic actuator is remotely powered by a constant voltage regardless of movements of the device within an effective range of translation and rotation. This in turn contributes to a predictable dose release rate and greater flexibility in the positioning of external powering source. We have conducted proof-of-concept drug delivery studies using the liquid drug in reservoir approach and the solid drug in reservoir approach, respectively. Our experimental results demonstrate that the range of flow rate is mainly determined by the voltage controlled with a Zener diode and the resistance of the implantable device. The latter can be adjusted by connecting different resistors, providing control over the flow rate to meet different clinical needs. The flow rate can be maintained at a constant level within the effective movement range. When using a solid drug substitute with a low solubility, solvent blue 38, the dose release can be kept at 2.36μg/cycle within the effective movement range by using an input voltage of 10Vpp and a load of 1.5 kΩ, which indicates the feasibility and controllability of our system without any complicated closed-loop sensor.

  2. Demand Response Load Following of Source and Load Systems

    DEFF Research Database (Denmark)

    Hu, Jianqiang; Cao, Jinde; Yong, Taiyou

    2017-01-01

    capacities and regulation rates of aggregators. Based on the evaluation results, the dispatch center optimizes the real time load following trajectories for the generating units and the flexible load agents via look-ahead optimization by considering the injection of renewable power. Furthermore, we mainly...

  3. Formulation consideration and characterization of microemulsion drug delivery system for transnasal administration of carbamazepine

    OpenAIRE

    Rashmin B. Patel; Mrunali R. Patel; BHATT, Kashyap K.; Bharat G. Patel

    2013-01-01

    The purpose of the present study was to formulate and characterize carbamazepine loaded microemulsion and mucoadhesive microemulsion drug delivery system for its intranasal administration. Carbamazepine microemulsion and mucoadhesive microemulsion were prepared by titration method. The drug-loaded microemulsions were successfully prepared which contain 6% Labrafil M 1944 CS as an oily phase, 32% surfactant mixture of Cremophor RH 40: Transcutol P (4:1) and 62% (wt/wt) aqueous phase. Microemul...

  4. Modelling of Generic Slung Load System

    DEFF Research Database (Denmark)

    Bisgaard, Morten; Bendtsen, Jan Dimon; La Cour-Harbo, Anders

    2006-01-01

    This paper presents the result of modelling and verification of a generic slung load system using a small-scale helicopter. The model is intended for use in simulation, pilot training, estimation, and control. The model is derived using a redundant coordinate formulation based on Gauss Principle ...

  5. Bionanocomposites containing magnetic graphite as potential systems for drug delivery.

    Science.gov (United States)

    Ribeiro, Lígia N M; Alcântara, Ana C S; Darder, Margarita; Aranda, Pilar; Herrmann, Paulo S P; Araújo-Moreira, Fernando M; García-Hernández, Mar; Ruiz-Hitzky, Eduardo

    2014-12-30

    New magnetic bio-hybrid matrices for potential application in drug delivery are developed from the assembly of the biopolymer alginate and magnetic graphite nanoparticles. Ibuprofen (IBU) intercalated in a Mg-Al layered double hydroxide (LDH) was chosen as a model drug delivery system (DDS) to be incorporated as third component of the magnetic bionanocomposite DDS. For comparative purposes DDS based on the incorporation of pure IBU in the magnetic bio-hybrid matrices were also studied. All the resulting magnetic bionanocomposites were processed as beads and films and characterized by different techniques with the aim to elucidate the role of the magnetic graphite on the systems, as well as that of the inorganic brucite-like layers in the drug-loaded LDH. In this way, the influence of both inorganic components on the mechanical properties, the water uptake ability, and the kinetics of the drug release from these magnetic systems were determined. In addition, the possibility of modulating the levels of IBU release by stimulating the bionanocomposites with an external magnetic field was also evaluated in in vitro assays. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Curcumin loaded in bovine serum albumin–chitosan derived nanoparticles for targeted drug delivery

    Indian Academy of Sciences (India)

    SRIDHAR SKYLAB RAJAN; AKILA PANDIAN; TAMILSELVI PALANIAPPAN

    2016-06-01

    The main aim of this study is to prepare biocompatible polymeric nanoparticles for targeted delivery of curcumin to human colorectal adenocarcinoma (DLD-1) cells. Curcumin has an ability to block proliferation ofcancer cells by suppressing the nuclear transcription factor NF-KB hence, it is chosen as drug in the current study. To avoid its low bio-availability, high dosage and poor aqueous solubility, curcumin nanoparticles are prepared and loaded in naturally available biopolymers like chitosan and bovine serum albumin (BSA) by nanoprecipitation method at pH 6.3. The prepared nanoformulation was then characterized for surface morphology, particle size, polydispersity index, FT-IR spectra, UV–Visible spectrometer, confocal microscopy and in vitro cytotoxicity studies. Results showed that sizes of the prepared nanoparticles were ranged between 181 and 363 nm and curcumin-loaded particles were selectively targeting colorectal carcinoma cells effectively when concentration gets increased. So this study proved that BSA–chitosan based nanoparticles can be used as an efficient vehicle for effective curcumin delivery in treatment of cancer cells.

  7. Statistical optimization of insulin-loaded Pluronic F-127 gels for buccal delivery of basal insulin.

    Science.gov (United States)

    Das, Nilanjana; Madan, Parshotam; Lin, Senshang

    2012-01-01

    The principle of statistical optimization was employed to fabricate insulin-loaded Pluronic F-127 (PF-127) gel formulations having the potential for buccal delivery of basal insulin. A two-level resolution III fractional factorial design was applied to simultaneously evaluate five independent formulation variables: PF-127 concentration, insulin concentration, sodium sulfate concentration, hydroxypropylmethyl cellulose (HPMC) concentration, and presence of sodium glycocholate. The amount of insulin released and permeated from gels as well as gelation time and mucoadhesion force of gels were measured and used as dependent response variables for formulation optimization. Optimization of a gel formulation was achieved by applying constrained optimization via regression analysis. In vitro permeation flux of insulin from the optimized formulation through procine buccal mucosa was 93.17 (±0.058, n = 3) μg/cm(2). Plasma insulin levels following buccal administration of the optimized formulation at 10, 25 and 50 IU/kg to healthy rats were found to be dose dependent and basal insulin levels were maintained at least for 8 h. Furthermore, continuous hypoglycemia for at least 8 h was observed with 89%, 51% and 25% of blood glucose reduction, respectively, for these three doses. The results of this investigation conclude the feasibility of development of optimized buccal insulin-loaded Pluronic F-127 gels for basal insulin delivery.

  8. Ultrasound triggered image-guided drug delivery to inhibit vascular reconstruction via paclitaxel-loaded microbubbles.

    Science.gov (United States)

    Zhu, Xu; Guo, Jun; He, Cancan; Geng, Huaxiao; Yu, Gengsheng; Li, Jinqing; Zheng, Hairong; Ji, Xiaojuan; Yan, Fei

    2016-02-22

    Paclitaxel (PTX) has been recognized as a promising drug for intervention of vascular reconstructions. However, it is still difficult to achieve local drug delivery in a spatio-temporally controllable manner under real-time image guidance. Here, we introduce an ultrasound (US) triggered image-guided drug delivery approach to inhibit vascular reconstruction via paclitaxel (PTX)-loaded microbubbles (PLM) in a rabbit iliac balloon injury model. PLM was prepared through encapsulating PTX in the shell of lipid microbubbles via film hydration and mechanical vibration technique. Our results showed PLM could effectively deliver PTX when exposed to US irradiation and result in significantly lower viability of vascular smooth muscle cells. Ultrasonographic examinations revealed the US signals from PLM in the iliac artery were greatly increased after intravenous administration of PLM, making it possible to identify the restenosis regions of iliac artery. The in vivo anti-restenosis experiments with PLM and US greatly inhibited neointimal hyperplasia at the injured site, showing an increased lumen area and reduced the ratio of intima area and the media area (I/M ratio). No obvious functional damages to liver and kidney were observed for those animals. Our study provided a promising approach to realize US triggered image-guided PTX delivery for therapeutic applications against iliac restenosis.

  9. Development and evaluation of Desvenlafaxine loaded PLGA-chitosan nanoparticles for brain delivery

    Directory of Open Access Journals (Sweden)

    Gui-Feng Tong

    2017-09-01

    Full Text Available Depression is a debilitating psychiatric condition that remains the second most common cause of disability worldwide. Currently, depression affects more than 4 per cent of the world’s population. Most of the drugs intended for clinical management of depression augment the availability of neurotransmitters at the synapse by inhibiting their neuronal reuptake. However, the therapeutic efficacy of antidepressants is often compromised as they are unable to reach brain by the conventional routes of administration. The purpose of the present study was to reconnoiter the potential of mucoadhesive PLGA-chitosan nanoparticles for the delivery of encapsulated Desvenlafaxine to the brain by nose to brain delivery route for superior pharmacokinetic and pharmacodynamic profile of Desvenlafaxine. Desvenlafaxine loaded PLGA-chitosan nanoparticles were prepared by solvent emulsion evaporation technique and optimized for various physiochemical characteristics. The antidepressant efficacy of optimized Desvenlafaxine was evaluated in various rodent depression models together with the biochemical estimation of monoamines in their brain. Further, the levels of Desvenlafaxine in brain and blood plasma were determined at various time intervals for calculation of different pharmacokinetic parameters. The optimized Desvenlafaxine loaded PLGA-chitosan nanoparticles (∼172 nm/+35 mV on intranasal administration significantly reduced the symptoms of depression and enhanced the level of monoamines in the brain in comparison with orally administered Desvenlafaxine. Nose to brain delivery of Desvenlafaxine PLGA-chitosan nanoparticles also enhanced the pharmacokinetic profile of Desvenlafaxine in brain together with their brain/blood ratio at different time points. Thus, intranasal mucoadhesive Desvenlafaxine PLGA-chitosan nanoparticles could be potentially used for the treatment of depression.

  10. Nanoemulsion: A new concept of delivery system

    Directory of Open Access Journals (Sweden)

    Nitin Sharma

    2010-01-01

    Full Text Available Nanoemulsion has been identified as a promising delivery system for various drugs including biopharmaceuticals. Nanoemulsion is a heterogeneous system composed of one immiscible liquid dispersed as droplets within another liquid. The droplets size of nano emulsion is between 20 to 500 nm. Diameter and surface properties of droplets of nanoemulsion plays an important role in the biological behavior of the formulation. Small droplet sizes lead to transparent emulsions so that product appearance is not altered by the addition of an oil phase. In this paper various aspects of nanoemulsion have been discussed including advantages, disadvantages and methods of preparation. Furthermore new approaches of stability of formulation, effect of types and concentration of surfactant, process variables and method are also discussed to improve the stability of nanoemulsion formulation

  11. An Insight into Ophthalmic Drug Delivery System

    Directory of Open Access Journals (Sweden)

    Rathore K. S.

    2009-04-01

    Full Text Available Promising management of eye ailments take off effective concentration of drug at the eye for sufficient period of time. Dosage forms are administered directly to eye for localized ophthalmic therapy. Most of the treatments call for the topical administration of ophthalmic active drugs to the tissues around the ocular cavity. Conventional ophthalmic drug delivery systems including eye drops, ophthalmic ointments, are no longer sufficient to encounter eye diseases. This article reviews the constraints with conventional ocular therapy and explores various novel approaches like in-situ gel, ocular films or ocuserts, nanosuspension, collagen shields, latex systems, nanoparticles, liposomes, niosomes, iontophorosis, eye implants, etc to improve the ophthalmic bioavailability of drugs to the anterior chamber of the eye.

  12. A telemedicine health care delivery system

    Science.gov (United States)

    Sanders, Jay H.

    1991-01-01

    The Interactive Telemedicine Systems (ITS) system was specifically developed to address the ever widening gap between our medical care expertise and our medical care delivery system. The frustrating reality is that as our knowledge of how to diagnose and treat medical conditions has continued to advance, the system to deliver that care has remained in an embryonic stage. This has resulted in millions of people being denied their most basic health care needs. Telemedicine utilizes an interactive video system integrated with biomedical telemetry that allows a physician at a base station specialty medical complex or teaching hospital to examine and treat a patient at multiple satellite locations, such as rural hospitals, ambulatory health centers, correctional institutions, facilities caring for the elderly, community hospital emergency departments, or international health facilities. Based on the interactive nature of the system design, the consulting physician at the base station can do a complete history and physical examination, as if the patient at the satellite site was sitting in the physician's office. This system is described.

  13. Improved cytotoxicity of paclitaxel loaded in nanosized lipid carriers by intracellular delivery

    Science.gov (United States)

    Miao, Jing; Du, Yongzhong; Yuan, Hong; Zhang, Xingguo; Li, Qian; Rao, Yuefeng; Zhao, Mengdan; Hu, Fuqiang

    2015-01-01

    Nanosized lipid carriers (NLC) can improve the limited drug-loading (DL) capacity and drug expulsion during storage, and adjust the drug release profile of solid lipid nanoparticles (SLN). In this study, Paclitaxel (PTX)-loaded NLC were prepared by solvent diffusion method using monostearin as solid lipid and oleic acid (OA) as liquid lipid matrix. The blank NLC with different OA content (the size range was from 89.5 ± 7.4 to 160.2 ± 34.6 nm) showed smaller size than the blank SLN (the size was 272.7 ± 43.6 nm), while the PTX-loaded NLC (the size range was from 481.3 ± 29.8 to 561.7 ± 38.3 nm) showed little bigger size, higher DL capacity, and faster drug in vitro release rate comparing with SLN (the size was 437.3 ± 68.2 nm). The 50 % cellular growth inhibitions (IC50) of PTX-loaded NLC with 0, 5, 10, and 20 wt % OA were 0.92 ± 0.06, 0.69 ± 0.04, 0.25 ± 0.02, and 0.12 ± 0.02 µg mL-1, respectively, while the IC50 of TaxolTM was 1.72 ± 0.09 µg mL-1. For analyzing cellular drug effect, cellular uptakes of fluorescent NLC and intracellular drug concentration were investigated. As the incorporation of OA into solid lipid matrix could accelerate both the cellular uptake and the PTX delivery, loaded by NLC, the cytotoxicity of PTX could be enhanced, and further enhanced by increasing OA content in NLC.

  14. Nanostructured lipid carriers as a delivery system of biochanin A.

    Science.gov (United States)

    Wang, Qiang; Cheng, Hailin; Zhou, Kai; Wang, Lei; Dong, Shixin; Wang, Dianlei; Chen, Weidong

    2013-11-01

    The aim of this study was to explore the nanostructured lipid carriers as a delivery system of biochanin A so as to supply a method to improve its bioavailability. Biochanin A-loaded nanostructured lipid carriers (BCA-NLCs) were prepared by the method of emulsion-evaporation and low temperature solidification. Pharmacokinetics was carried out in rats upon oral administration at a dose of 10 mg/kg. BCA-NLC showed spherical formulation and had mean diameter 174.68±0.96 nm, zeta potential -20.9±0.8 mv and entrapment efficiency 97.36±0.14%. DSC and XRD studies indicated that BCA was not in crystal state in NLC. In in vitro release study, the BCA from BCA-NLC exhibited a biphasic release pattern with burst release initially and sustained release afterwards. BCA-NLC showed higher AUC value and circulated in blood for a longer time than BCA suspension. The studies demonstrated that NLC could be a potential delivery system for BCA to improve bioavailability.

  15. Rapid cycling medical synchrotron and beam delivery system

    Science.gov (United States)

    Peggs, Stephen G [Port Jefferson, NY; Brennan, J Michael [East Northport, NY; Tuozzolo, Joseph E [Sayville, NY; Zaltsman, Alexander [Commack, NY

    2008-10-07

    A medical synchrotron which cycles rapidly in order to accelerate particles for delivery in a beam therapy system. The synchrotron generally includes a radiofrequency (RF) cavity for accelerating the particles as a beam and a plurality of combined function magnets arranged in a ring. Each of the combined function magnets performs two functions. The first function of the combined function magnet is to bend the particle beam along an orbital path around the ring. The second function of the combined function magnet is to focus or defocus the particle beam as it travels around the path. The radiofrequency (RF) cavity is a ferrite loaded cavity adapted for high speed frequency swings for rapid cycling acceleration of the particles.

  16. A Novel Drug Delivery System for Osteosarcoma Chemotherapy

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A thermo-responsive chitosan hydrogel system (TRCHS) was prepared by chitosan ( CS ) andβ- glycerophosphate ( β- GP ) to deliver Adriamycin (ADM) locally for curing osteosarcoma . Release property was investigated by release experiments in vitro and results show that it can be applied to local drug release because it is able to release drug at high concentration for 17 days. The treatment effect was studied by injecting intratumorally to osteosarcoma tumors ( CRL- 1427) implanted subcutaneously on Specific Pathogen-free (SPF) mice. The statistical analytical results show that TRCHS delivering ADM is more efficacious than saline intratumoral injection,which loads the same quantity of ADM , but is less poisonous. Based on the analysis above, this novel biodegradable polymer implant is an effective and safe vehicle for sustained local delivery of ADM, and is supposed to be applied in neoadjuvant chemotherapy for osteosarcoma.

  17. Endothelial delivery of antioxidant enzymes loaded into non-polymeric magnetic nanoparticles.

    Science.gov (United States)

    Chorny, Michael; Hood, Elizabeth; Levy, Robert J; Muzykantov, Vladimir R

    2010-08-17

    Antioxidant enzymes have shown promise as a therapy for pathological conditions involving increased production of reactive oxygen species (ROS). However the efficiency of their use for combating oxidative stress is dependent on the ability to achieve therapeutically adequate levels of active enzymes at the site of ROS-mediated injury. Thus, the implementation of antioxidant enzyme therapy requires a strategy enabling both guided delivery to the target site and effective protection of the protein in its active form. To address these requirements we developed magnetically responsive nanoparticles (MNP) formed by precipitation of calcium oleate in the presence of magnetite-based ferrofluid (controlled aggregation/precipitation) as a carrier for magnetically guided delivery of therapeutic proteins. We hypothesized that antioxidant enzymes, catalase and superoxide dismutase (SOD), can be protected from proteolytic inactivation by encapsulation in MNP. We also hypothesized that catalase-loaded MNP applied with a high-gradient magnetic field can rescue endothelial cells from hydrogen peroxide toxicity in culture. To test these hypotheses, a family of enzyme-loaded MNP formulations were prepared and characterized with respect to their magnetic properties, enzyme entrapment yields and protection capacity. SOD- and catalase-loaded MNP were formed with average sizes ranging from 300 to 400 nm, and a protein loading efficiency of 20-33%. MNP were strongly magnetically responsive (magnetic moment at saturation of 14.3 emu/g) in the absence of magnetic remanence, and exhibited a protracted release of their cargo protein in plasma. Catalase stably associated with MNP was protected from proteolysis and retained 20% of its initial enzymatic activity after 24h of exposure to pronase. Under magnetic guidance catalase-loaded MNP were rapidly taken up by cultured endothelial cells providing increased resistance to oxidative stress (62+/-12% cells rescued from hydrogen peroxide induced

  18. Leadership Dynamics Promoting Systemic Reform for Inclusive Service Delivery

    Science.gov (United States)

    Scanlan, Martin

    2009-01-01

    This article presents a multicase study of two systems of schools striving to reform service delivery systems for students with special needs. Considering these systems as institutional actors, the study examines what promotes the understanding and implementation of special education service delivery within a system of schools in a manner that…

  19. Evaluation of tropicamide-loaded tamarind seed xyloglucan nanoaggregates for ophthalmic delivery.

    Science.gov (United States)

    Dilbaghi, Neeraj; Kaur, Harmanmeet; Ahuja, Munish; Kumar, Sandeep

    2013-04-15

    The present study was aimed to prepare tamarind seed nanoaggregates and its evaluation for ophthalmic delivery. The preparation of tropicamide-loaded tamarind seed xyloglucan nanoaggregates was optimized using face centred central composite experimental design, employing the concentrations of tamarind seed xyloglucan and Poloxamer-407, as independent variables. The results revealed that concentration of TSX has a significant antagonistic effect on particle size, while poloxamer displayed a significant synergistic effect on encapsulation efficiency. The optimal concentrations of TSX and poloxamer were found to be 0.45% (w/v) and 0.5% (w/v) respectively. The optimized formulation of tropicamide-loaded TSX nanoaggregates showed a significantly higher corneal permeation of tropicamide across the isolated goat cornea compared to commercial conventional aqueous formulation. The results revealed excellent mucoadhesive properties of TSX nanoaggregates. Further, the tropicamide-loaded TSX nanoaggregates formulation showed excellent ocular tolerance and biocompatibility as determined by hen's egg test chorioallantoic membrane and resazurin assay on Vero cell lines.

  20. Transdermal Patches: A Complete Review on Transdermal Drug Delivery System

    Directory of Open Access Journals (Sweden)

    Patel DS

    2012-03-01

    Full Text Available Today about 70% of drugs are taken orally and are found not to be as effective as desired. To improvesuch characters transdermal drug delivery system was emerged. Transdermal drug delivery system(TDDS provides a means to sustain drug release as well as reduce the intensity of action and thusreduce the side effects associated with its oral therapy and differs from traditional topical drug delivery.Transdermal Drug Delivery System is the system in which the delivery of the active ingredients of thedrug occurs by means of skin. Several important advantages of transdermal drug delivery are limitationof hepatic first pass metabolism, enhancement of therapeutic efficiency and maintenance of steadyplasma level of the drug. Various types of transdermal patches are used to incorporate the activeingredients into the circulatory system via skin. This review article covers a brief outline of theprinciples of transdermal permeation, various components of transdermal patch, approaches oftransdermal patch, evaluation of transdermal system, its application with its limitation.

  1. Polymers for Pharmaceutical Packaging and Delivery Systems

    DEFF Research Database (Denmark)

    Fristrup, Charlotte Juel

    -bromoisobutyrate initiating sites. Each modification step of PEEK as well as grafting of poly(ethylene glycol) methacrylate (PEGMA) was followed and confirmed by Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy, water contact angle (WCA) measurements, and Thermal Gravimetric Analysis....... X-ray Photoelectron Spectroscopy also confirmed the presence of the poly(PEGMA) grafts on the PEEK surface by comparing the C/O ratio and the chemical composition after each modification step. The surface topography was evaluated by Atomic Force Microscopy. Polypropylene (PP) is one of the polymeric...... materials of interest for pharmaceutical packaging and delivery systems. Confocal fluorescence microscopy studies and stability studies with insulin aspart (AspB28 insulin) were conducted to evaluate the impact of modified PP compared to unmodified PP. In contrast to PEEK, PP did not contain any functional...

  2. Versatile RNA interference nanoplatform for systemic delivery of RNAs.

    Science.gov (United States)

    Choi, Ki Young; Silvestre, Oscar F; Huang, Xinglu; Min, Kyung Hyun; Howard, Gregory P; Hida, Naoki; Jin, Albert J; Carvajal, Nicole; Lee, Sang Wook; Hong, Jong-In; Chen, Xiaoyuan

    2014-05-27

    Development of nontoxic, tumor-targetable, and potent in vivo RNA delivery systems remains an arduous challenge for clinical application of RNAi therapeutics. Herein, we report a versatile RNAi nanoplatform based on tumor-targeted and pH-responsive nanoformulas (NFs). The NF was engineered by combination of an artificial RNA receptor, Zn(II)-DPA, with a tumor-targetable and drug-loadable hyaluronic acid nanoparticle, which was further modified with a calcium phosphate (CaP) coating by in situ mineralization. The NF can encapsulate small-molecule drugs within its hydrophobic inner core and strongly secure various RNA molecules (siRNAs, miRNAs, and oligonucleotides) by utilizing Zn(II)-DPA and a robust CaP coating. We substantiated the versatility of the RNAi nanoplatform by demonstrating effective delivery of siRNA and miRNA for gene silencing or miRNA replacement into different human types of cancer cells in vitro and into tumor-bearing mice in vivo by intravenous administration. The therapeutic potential of NFs coloaded with an anticancer drug doxorubicin (Dox) and multidrug resistance 1 gene target siRNA (siMDR) was also demonstrated in this study. NFs loaded with Dox and siMDR could successfully sensitize drug-resistant OVCAR8/ADR cells to Dox and suppress OVCAR8/ADR tumor cell proliferation in vitro and tumor growth in vivo. This gene/drug delivery system appears to be a highly effective nonviral method to deliver chemo- and RNAi therapeutics into host cells.

  3. Printing technologies in fabrication of drug delivery systems

    DEFF Research Database (Denmark)

    Kolakovic, Ruzica; Viitala, Tapani; Ihalainen, Petri

    2013-01-01

    INTRODUCTION: There has been increased activity in the field recently regarding the development and research on various printing techniques in fabrication of dosage forms and drug delivery systems. These technologies may offer benefits and flexibility in manufacturing, potentially paving the way...... recent literature where printing techniques are used in fabrication of drug delivery systems. The future perspectives and possible impacts on formulation strategies, flexible dosing and personalized medication of using printing techniques for fabrication of drug delivery systems are discussed.......\

  4. Protein nanoparticle: A unique system as drug delivery vehicles

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-29

    . ... contributions in the field of protein nanoparticles used as drug delivery systems. .... tic guidance. ..... response of cytoskeletal organization and adhesion ..... Helicobacter Pylori Effect of Mucoadhesive Nanoparticles Bearing.

  5. Miconazole-loaded nanostructured lipid carriers (NLC) for local delivery to the oral mucosa: improving antifungal activity.

    Science.gov (United States)

    Mendes, A I; Silva, A C; Catita, J A M; Cerqueira, F; Gabriel, C; Lopes, C M

    2013-11-01

    Miconazole is a widely used antifungal agent with poor aqueous solubility, which requires the development of drug delivery systems able to improve its therapeutic activity. For this purpose, a miconazole-loaded nanostructured lipid carriers (NLC) dispersion was prepared and characterized. Further, the dispersion was used to prepare a NLC-based hydrogel formulation proposed as an alternative system to improve the local delivery of miconazole to the oral mucosa. NLC dispersion showed particles in the nanometer range (≈ 200 nm) with low polidispersity index (87%). A controlled miconazole release was observed from NLC and NLC-based hydrogel formulations, in contrast to a commercial oral gel formulation, which demonstrated a faster release. Additionally, it was observed that the encapsulation of miconazole in the NLC improved its antifungal activity against Candida albicans. Therefore, it was demonstrated that the encapsulation of miconazole in NLC allows for obtaining the same therapeutic effect of a commercial oral gel formulation, using a 17-fold lower dose of miconazole. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. STRATEGIES AND PROSPECTS OF NASAL DRUG DELIVERY SYSTEMS

    Directory of Open Access Journals (Sweden)

    Gannu Praveen Kumar

    2012-03-01

    Full Text Available The recent advancement of nasal drug delivery systems has increased enormously and is gaining significant importance. Intranasal therapy has been an accepted form of treatment in the Ayurvedic system of Indian Medicine. The non-invasive delivery of nasal drug delivery systems made to exploit for the development of successful treatment. The advantages, disadvantages, mechanism of action and application of nasal drug delivery system in local delivery, systematic delivery, nasal vaccines and CNS delivery are explained lucidly. The relevant aspects of biological, physicochemical and pharmaceutical factors of nasal cavity that must be considered during the process of discovery and development of new drugs for nasal delivery as well as in their incorporation into appropriate nasal pharmaceutical formulations are also discussed. Nasal route is more suitable for those drugs which cannot be administered orally due to gastric degradation or hepatic first pass metabolism of the drug. Intranasal drug delivery is found much promising route for administration of peptides and protein drugs. Much has been investigated and much more are to be investigated for the recent advancement of nasal drug delivery systems.

  7. Potential and problems in ultrasound-responsive drug delivery systems

    Directory of Open Access Journals (Sweden)

    Zhao YZ

    2013-04-01

    Full Text Available Ying-Zheng Zhao,1,3 Li-Na Du,2 Cui-Tao Lu,1 Yi-Guang Jin,2 Shu-Ping Ge3 1Wenzhou Medical College, Wenzhou City, Zhejiang Province, 2Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, Beijing, People’s Republic of China; 3St Christopher’s Hospital for Children/Drexel University College of Medicine, Philadelphia, PA, USA Abstract: Ultrasound is an important local stimulus for triggering drug release at the target tissue. Ultrasound-responsive drug delivery systems (URDDS have become an important research focus in targeted therapy. URDDS include many different formulations, such as microbubbles, nanobubbles, nanodroplets, liposomes, emulsions, and micelles. Drugs that can be loaded into URDDS include small molecules, biomacromolecules, and inorganic substances. Fields of clinical application include anticancer therapy, treatment of ischemic myocardium, induction of an immune response, cartilage tissue engineering, transdermal drug delivery, treatment of Huntington’s disease, thrombolysis, and disruption of the blood–brain barrier. This review focuses on recent advances in URDDS, and discusses their formulations, clinical application, and problems, as well as a perspective on their potential use in the future. Keywords: ultrasound, targeted therapy, clinical application

  8. Exogenous DNA Loading into Extracellular Vesicles via Electroporation is Size-Dependent and Enables Limited Gene Delivery.

    Science.gov (United States)

    Lamichhane, Tek N; Raiker, Rahul S; Jay, Steven M

    2015-10-01

    Extracellular vesicles (EVs) hold immense promise for utilization as biotherapeutics and drug delivery vehicles due to their nature as biological nanoparticles that facilitate intercellular molecular transport. Specifically, EVs have been identified as natural carriers of nucleic acids, sparking interest in their use for gene therapy and RNA interference applications. So far, small RNAs (siRNA and miRNA) have been successfully loaded into EVs for a variety of delivery applications, but the potential use of EVs for DNA delivery has scarcely been explored. Here, we report that exogenous linear DNA can be associated with EVs via electroporation in quantities sufficient to yield an average of hundreds of DNA molecules per vesicle. We determined that loading efficiency and capacity of DNA in EVs is dependent on DNA size, with linear DNA molecules less than 1000 bp in length being more efficiently associated with EVs compared to larger linear DNAs and plasmid DNAs using this approach. We further showed that EV size is also determinant with regard to DNA loading, as larger microvesicles encapsulated more linear and plasmid DNA than smaller, exosome-like EVs. Additionally, we confirmed the ability of EVs to transfer foreign DNA loaded via electroporation into recipient cells, although functional gene delivery was not observed. These results establish critical parameters that inform the potential use of EVs for gene therapy and, in agreement with other recent results, suggest that substantial barriers must be overcome to establish EVs as broadly applicable DNA delivery vehicles.

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

    Science.gov (United States)

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

    2015-07-25

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

  10. Loading Schemes for Downlink OFDMA Systems

    Institute of Scientific and Technical Information of China (English)

    KONG Jian; LIU Fang; WANG Wen-bo; LIU Yuan-an

    2004-01-01

    In this paper we study the subcarrier and bit allocation strategies for downlink OFDMA system. Our optimization objective is to find optimum subcarrier and bit assignment minimizing the total transmitted power with the constraints on BER and data rate for all users. We divide this problem into three steps: resource allocation, subcarrier assignment and single-user power and bit allocation. For the first two steps we propose new algorithms. Various loading schemes constitute by combining these algorithms as well as algorithms proposed in Ref . [ 6 ]. Simulation results demonstrate that our proposed suboptimal loading scheme can achieve performance closer to the near optimal algorithm in Ref . [ 8 ] with much lower complexity than schemes in Ref .[6].

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

    Science.gov (United States)

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

    2010-01-01

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

  12. MICROENCAPSULATION: AN INDISPENSABLE TECHNOLOGY FOR DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Malakar Jadupati

    2012-04-01

    Full Text Available In this review, the various new and well established technologies relevant to the controlled and targeted drug delivery systems have been precisely discussed. A perfectly designed controlled drug delivery system can be of huge advantage towards solving problems concerning to the targeting of drug to a specific organ or tissue and controlling the rate of drug delivery at the target site. Novel drug delivery systems have various advantages over other conventional drug therapy. In which microencapsulation is one approach for achieving the novel drug delivery dosage forms such as sustained release and controlled release, though the development of oral controlled release systems has been a challenge to formulation scientist due to their inability to restrain and focus the system at targeted areas of gastrointestinal tract. Microparticulate drug delivery systems are an interesting and promising option when developing an oral controlled release system. Our objective is to take a closer look at microparticles as drug delivery devices for increasing efficiency of drug delivery, improving the release profile and drug targeting. In order to elucidate the application of microcapsules in drug delivery, some fundamental aspects are briefly reviewed.

  13. Lactoferrin-modified PEGylated liposomes loaded with doxorubicin for targeting delivery to hepatocellular carcinoma.

    Science.gov (United States)

    Wei, Minyan; Guo, Xiucai; Tu, Liuxiao; Zou, Qi; Li, Qi; Tang, Chenyi; Chen, Bao; Xu, Yuehong; Wu, Chuanbin

    2015-01-01

    Lactoferrin (Lf) is a potential-targeting ligand for hepatocellular carcinoma (HCC) cells because of its specific binding with asialoglycoprotein receptor (ASGPR). In this present work, a doxorubicin (DOX)-loaded, Lf-modified, polyethylene glycol (PEG)ylated liposome (Lf-PLS) system was developed, and its targeting effect and antitumor efficacy to HCC was also explored. The DOX-loaded Lf-PLS system had spherical or oval vesicles, with mean particle size approximately 100 nm, and had an encapsulation efficiency of 97%. The confocal microscopy and flow cytometry indicated that the cellular uptake of Lf-PLS was significantly higher than that of PEGylated liposome (PLS) in ASGPR-positive cells (PASGPR-negative cells (P>0.05). Cytotoxicity assay by MTT demonstrated that DOX-loaded Lf-PLS showed significantly stronger antiproliferative effects on ASGPR-positive HCC cells than did PLS without the Lf modification (P<0.05). The in vivo antitumor studies on male BALB/c nude mice bearing HepG2 xenografts demonstrated that DOX-loaded Lf-PLS had significantly stronger antitumor efficacy compared with PLS (P<0.05) and free DOX (P<0.05). All these results demonstrated that a DOX-loaded Lf-PLS might have great potential application for HCC-targeting therapy.

  14. Advanced drug delivery systems: Nanotechnology of health design A review

    OpenAIRE

    Javad Safari; Zohre Zarnegar

    2014-01-01

    Nanotechnology has finally and firmly entered the realm of drug delivery. Performances of intelligent drug delivery systems are continuously improved with the purpose to maximize therapeutic activity and to minimize undesirable side-effects. This review describes the advanced drug delivery systems based on micelles, polymeric nanoparticles, and dendrimers. Polymeric carbon nanotubes and many others demonstrate a broad variety of useful properties. This review emphasizes the main requirements ...

  15. Recent development in novel drug delivery systems of herbal drugs

    OpenAIRE

    Mayank Chaturvedi; Manish Kumar; Amit Sinhal; Alimuddin Saifi

    2011-01-01

    Novel technologies have been developed recently for drug delivery systems. The use of herbal formulations for novel drug delivery systems is more advantageous and has more benefits compared to others. The use of liposome, ethosome, phytosomes, emulsion, microsphere, solid lipid nanoparticles of herbal formulation has enhanced the therapeutic effects of plant extracts. With the use of all these, targeted delivery of the formulation is achieved, due to which the formulation demonstrates effect ...

  16. Energy efficiency analysis of reconfigured distribution system for practical loads

    Directory of Open Access Journals (Sweden)

    Pawan Kumar

    2016-09-01

    Full Text Available In deregulated rate structure, the performance evaluation of distribution system for energy efficiency includes; loss minimization, improved power quality, loadability limit, reliability and availability of supply. Energy efficiency changes with the variation in loading pattern and the load behaviour. Further, the nature of load at each node is not explicitly of any one type rather their characteristics depend upon the node voltages. In most cases, load is assumed to be constant power (real and reactive. In this paper voltage dependent practical loads are represented with composite load model and the energy efficiency performance of distribution system for practical loads is evaluated in different configurations of 33-node system.

  17. REVIEW ON ADVANCES IN COLON TARGETED DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Sunena Sethi, SL Harikumar* and Nirmala

    2012-09-01

    Full Text Available The colon is the terminal part of the GIT which has gained in recent years as a potential site for delivery of various novel therapeutic drugs, i.e. peptides. However, colon is rich in microflora which can be used to target the drug release in the colon. Colon is a site where both local and systemic drug delivery can take place. Local delivery allows the topical treatment of inflammatory bowel disease. If drug can be targeted directly into the colon, treatment can become more effective and side effects can be minimized. These systemic side effects can be minimized by primary approaches for CDDS (Colon specific drug delivery namely prodrugs, pH and time dependent systems and microbially triggered system which gained limited success and have limitations as compared with recently new CDDS namely pressure controlled colon delivery capsules (PCDCS, CODESTM (Novel colon targeted delivery system osmotic controlled drug delivery system, Pulsincap system, time clock system, chronotropic system. This review is to understand the pharmaceutical approaches to colon targeted drug delivery systems for better therapeutic action without compromising on drug degradation (or its low bioavailability.

  18. Preparation of lorazepam-loaded microemulsions for intranasal delivery and its pharmacokinetics.

    Science.gov (United States)

    Yao, J; Hou, L; Zhou, J P; Zhang, Z Q; Sun, L

    2009-10-01

    The purpose of this study was to develop a microemulsion system for intranasal delivery of lorazepam. The phase behavior and properties of microemulsions were characterized in a pseudo-ternary system composed of Cremophor EL 35/Transcutol P/Lauroglycol FCC or Labrafil M 1944CS/water, and intranasal absorption of lorazepam from microemulsions was investigated in rabbit. The microemulsions, comprising of FCC, Cremophor EL 35/Transcutol P (1.5:1) and water, were optimal for intranasal delivery of lorazepam. These systems had a higher solubilization capacity with the particle size of lorazepam from microemulsions at 0.38 mg/kg had the larger AUC(0-t), the longer half-life and the prolonged circulation time with the mean bioavailability of 80.84% for ME2 and 63.48% for ME8 as compared to the intramuscular injection at 0.16 mg/kg. These results indicate that microemulsions may bea promising approach for the intranasal delivery of lorazepam.

  19. Acrylated chitosan for mucoadhesive drug delivery systems.

    Science.gov (United States)

    Shitrit, Yulia; Bianco-Peled, Havazelet

    2017-01-30

    A new mucoadhesive polymer was synthesized by conjugating chitosan to poly(ethylene glycol)diacrylate (PEGDA) via the Michael type reaction. The product was characterized using NMR. Higher PEGDA grafting efficacy was observed with low molecular weight PEGDA (0.7kDa), compared to long 10kDa PEGDA. The acrylation percentage was calculated based on the reaction of ninhydrin with chitosan, and supported the qualitative NMR findings. The adhesive properties were studied by tensile test and rotating system involving detachment of polymer tablets from a fresh intestine sample. Chitosan modified with high molecular weight PEGDA presented improvement in mucoadhesive properties compared to both non-modified and thiolated chitosan. On the molecular level, rheology measurements of polymer/mucin mixtures provided additional evidence of strong interaction between modified chitosan and mucin glycoproteins. This new polymer shows promise as a useful polymeric carrier matrix for delivery systems, which could provide prolonged residence time of the vehicle on the mucosa surface. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Evaluation of neuropeptide loaded trimethyl chitosan nanoparticles for nose to brain delivery.

    Science.gov (United States)

    Kumar, Manoj; Pandey, Ravi Shankar; Patra, Kartik Chandra; Jain, Sunil Kumar; Soni, Muarai Lal; Dangi, Jawahar Singh; Madan, Jitender

    2013-10-01

    Leucine-enkephalin (Leu-Enk) is a neurotransmitter or neuromodulator in pain transmission. Due to non-addictive opioid analgesic activity of this peptide, it might have great potential in pain management. Leu-Enk loaded N-trimethyl chitosan (TMC) nanoparticles were prepared and evaluated as a brain delivery vehicle via nasal route. TMC biopolymer was synthesized and analyzed by (1)H NMR spectroscopy. TMC nanoparticles were prepared by ionic gelation method. Mean peptide encapsulation efficiency and loading capacity were 78.28±3.8% and 14±1.3%, respectively. Mean particle size, polydispersity index and zeta potential were found to be 443±23 nm, 0.317±0.17 and +15±2 mV respectively for optimized formulations. Apparent permeability coefficient (Papp) of Leu-Enk released from nanoparticles across the porcine nasal mucosa was determined to be 7.45±0.30×10(-6) cm s(-1). Permeability of Leu-Enk released from nanoparticles was 35 fold improved from the nasal mucosa as compared to Leu-Enk solution. Fluorescent microscopy of brain sections of mice showed higher accumulation of fluorescent marker NBD-F labelled Leu-Enk, when administered nasally by TMC nanoparticles, while low brain uptake of marker solution was observed. Furthermore, enhancement in brain uptake resulted into significant improvement in the observed antinociceptive effect of Leu-Enk as evidenced by hot plate and acetic acid induced writhing assay.

  1. Daidzein-loaded nanostructured lipid carriers-PLGA nanofibers for transdermal delivery.

    Science.gov (United States)

    Song, Jia; Fan, Xiucong; Shen, Qi

    2016-03-30

    Daidzein is one of the most effective candidates for treating cardiovascular and cerebrovascular disease. However, considering its poor oral absorption and limited bioavailability, daidzein-loaded nanostructured lipid carriers-PLGA nanofibers were designed to handle the drawbacks. Daidzein-NLCs were successfully prepared by an emulsification and low-temperature solidification method. The physicochemical characteristics of NLCs were evaluated afterwards. Based on the preparation of daidzein-loaded NLCs, Daidzein-NLCs-nanofibers were optimized by electrospinning and were observed under Scanning Electron Microscope to capture the appearance. The sustained release profile of daidzein from Daidzein-NLCs-nanofibers in vivo was best fitted to the Kormeyer-Peppas equation. The in vitro skin permeable behavior showed the cumulative amount of daidzein from Daidzein-NLCs-nanofibers reached 21.71 μg cm(-2) at 60 h, which was 3.78 times higher than pure daidzein solution. It demonstrated that the Daidzein-NLCs-nanofibers could significantly enhance the transported amount of drug. Confocal Laser Scanning Microscopy resulting images revealed a more effective content accumulation of Daidzein-NLCs-nanofibers than Daidzein-NLCs in epidermis. In vivo study indicated that Daidzein-NLCs-nanofibers had better skin retention than Daidzein-NLCs in the long term. The skin irritation experiment showed a positive result with no obvious stimulus observed. These results suggested that Daidzein-NLCs-nanofibers could be a potential candidate for transdermal delivery. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Multifunctional reduction-responsive SPIO&DOX-loaded PEGylated polymeric lipid vesicles for magnetic resonance imaging-guided drug delivery

    Science.gov (United States)

    Wang, Sheng; Yang, Weitao; Du, Hongli; Guo, Fangfang; Wang, Hanjie; Chang, Jin; Gong, Xiaoqun; Zhang, Bingbo

    2016-04-01

    Multifunctional superparamagnetic iron-oxide (SPIO)-based nanoparticles have been emerging as candidate nanosystems for cancer diagnosis and therapy. Here, we report the use of reduction- responsive SPIO/doxorubicin (DOX)-loaded poly(ethylene glycol) monomethyl ether (PEG)ylated polymeric lipid vesicles (SPIO&DOX-PPLVs) as a novel theranostic system for tumor magnetic resonance imaging (MRI) diagnosis and controlled drug delivery. These SPIO&DOX-PPLVs are composed of SPIOs that function as MR contrast agents for tumor enhancement and PPLVs as polymer matrices for encapsulating SPIO and antitumor drugs. The in vitro characterizations show that the SPIO&DOX-PPLVs have nanosized structures (˜80 nm), excellent colloidal stability, good biocompatibility, as well as T 2-weighted MRI capability with a relatively high T 2 relaxivity (r 2 = 213.82 mM-1 s-1). In vitro drug release studies reveal that the release rate of DOX from the SPIO&DOX-PPLVs is accelerated in the reduction environment. An in vitro cellular uptake study and an antitumor study show that the SPIO&DOX-PPLVs have magnetic targeting properties and effective antitumor activity. In vivo studies show the SPIO&DOX-PPLVs have excellent T 2-weighted tumor targeted MRI capability, image-guided drug delivery capability, and high antitumor effects. These results suggest that the SPIO&DOX-PPLVs are promising nanocarriers for MRI diagnosis and cancer therapy applications.

  3. Role of Components in the Formation of Self-microemulsifying Drug Delivery Systems.

    Science.gov (United States)

    Gurram, A K; Deshpande, P B; Kar, S S; Nayak, Usha Y; Udupa, N; Reddy, M S

    2015-01-01

    Pharmaceutical research is focused in designing novel drug delivery systems to improve the bioavailability of poorly water soluble drugs. Self-microemulsifying drug delivery systems, one among the lipid-based dosage forms were proven to be promising in improving the oral bioavailability of such drugs by enhancing solubility, permeability and avoiding first-pass metabolism via enhanced lymphatic transport. Further, they have been successful in avoiding both inter and intra individual variations as well as the dose disproportionality. Aqueous insoluble drugs, in general, show greater solubility in lipid based excipients, and hence they are formulated as lipid based drug delivery systems. The extent of solubility of a hydrophobic drug in lipid excipients i.e. oil, surfactant and co-surfactant (components of self-microemulsifying drug delivery systems) greatly affects the drug loading and in producing stable self-microemulsifying drug delivery systems. The present review highlighted the influence of physicochemical factors and structural features of the hydrophobic drug on its solubility in lipid excipients and an attempt was made to explore the role of each component of self-microemulsifying drug delivery systems in the formation of stable microemulsion upon dilution.

  4. NASAL IN SITU GEL: A NOVEL DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Dhrupesh panchal

    2012-06-01

    Full Text Available Over the past few decades, advances in the in situ gel technologies have spurred development in manymedical and biomedical applications including controlled drug delivery. Many novel in situ gel baseddelivery matrices have been designed and fabricated to fulfill the ever increasing needs of thepharmaceutical and medical fields. In situ gelling systems are liquid at room temperature but undergogelation when in contact with body fluids or change in pH. In situ gel forming drug delivery is a type ofmucoadhesive drug delivery system. The formation of gel depends on factors like temperaturemodulation, pH change, presence of ions and ultraviolet irradiation from which the drug gets released ina sustained and controlled manner. Nasal delivery is a promising drug delivery option where commondrug administrations such as intravenous, intramuscular or oral are inapplicable. Recently, it has beenshown that many drugs have better bioavailability by nasal route than the oral route. This has beenattributed to rich vasculature and a highly permeable structure of the nasal mucosa coupled withavoidance of hepatic first-pass elimination, gut wall metabolism and/or destruction in thegastrointestinal tract. The physiology of the nose presents obstacles but offers a promising route for noninvasivesystemic delivery of numerous therapies and debatably drug delivery route to the brain. Thusthis review focuses on nasal drug delivery, various aspects of nasal anatomy and physiology, nasal drugabsorption mechanisms, various nasal drug delivery systems and their applications in drug delivery.

  5. Improved cytotoxicity of paclitaxel loaded in nanosized lipid carriers by intracellular delivery

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Jing, E-mail: joemj1005@163.com, E-mail: miaojing@zju.edu.cn [Zhejiang University, Department of Pharmacy, the First Affiliated Hospital, College of Medicine (China); Du, Yongzhong; Yuan, Hong [Zhejiang University, College of Pharmaceutical Sciences (China); Zhang, Xingguo; Li, Qian; Rao, Yuefeng [Zhejiang University, Department of Pharmacy, the First Affiliated Hospital, College of Medicine (China); Zhao, Mengdan [Zhejiang University, Women’s Hospital, College of Medicine (China); Hu, Fuqiang, E-mail: hufq@zju.edu.cn [Zhejiang University, College of Pharmaceutical Sciences (China)

    2015-01-15

    Nanosized lipid carriers (NLC) can improve the limited drug-loading (DL) capacity and drug expulsion during storage, and adjust the drug release profile of solid lipid nanoparticles (SLN). In this study, Paclitaxel (PTX)-loaded NLC were prepared by solvent diffusion method using monostearin as solid lipid and oleic acid (OA) as liquid lipid matrix. The blank NLC with different OA content (the size range was from 89.5 ± 7.4 to 160.2 ± 34.6 nm) showed smaller size than the blank SLN (the size was 272.7 ± 43.6 nm), while the PTX-loaded NLC (the size range was from 481.3 ± 29.8 to 561.7 ± 38.3 nm) showed little bigger size, higher DL capacity, and faster drug in vitro release rate comparing with SLN (the size was 437.3 ± 68.2 nm). The 50 % cellular growth inhibitions (IC{sub 50}) of PTX-loaded NLC with 0, 5, 10, and 20 wt % OA were 0.92 ± 0.06, 0.69 ± 0.04, 0.25 ± 0.02, and 0.12 ± 0.02 µg mL{sup −1}, respectively, while the IC{sub 50} of Taxol{sup TM} was 1.72 ± 0.09 µg mL{sup −1}. For analyzing cellular drug effect, cellular uptakes of fluorescent NLC and intracellular drug concentration were investigated. As the incorporation of OA into solid lipid matrix could accelerate both the cellular uptake and the PTX delivery, loaded by NLC, the cytotoxicity of PTX could be enhanced, and further enhanced by increasing OA content in NLC.

  6. siRNA delivery with lipid-based systems

    DEFF Research Database (Denmark)

    Foged, Camilla

    2012-01-01

    in vivo, toxicity and non-specific stimulation of the immune system. To optimally design and tailor the lipidic systems for siRNA delivery, better insight is needed into the mechanisms of cell delivery. More specifically, further clarification is need regarding the nature of cell surface interactions...

  7. Guidelines for Psychological Practice in Health Care Delivery Systems

    Science.gov (United States)

    American Psychologist, 2013

    2013-01-01

    Psychologists practice in an increasingly diverse range of health care delivery systems. The following guidelines are intended to assist psychologists, other health care providers, administrators in health care delivery systems, and the public to conceptualize the roles and responsibilities of psychologists in these diverse contexts. These…

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

    OpenAIRE

    Meng, Ellis; Hoang, Tuan

    2012-01-01

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

  9. Load compensation for single phase system using series active filter

    African Journals Online (AJOL)

    user

    transmission system to low voltage distribution system, quite a good number of series ... Keywords: Active power filter (APF), current source type of harmonic load .... voltage source type harmonic loads are having diode rectifier with smoothing.

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

    Science.gov (United States)

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

    2013-06-28

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

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

    DEFF Research Database (Denmark)

    Christophersen, Philip Carsten; Fano, Mathias; Saaby, Lasse

    2015-01-01

    Oral drug delivery is a preferred route because of good patient compliance. However, most peptide/ protein drugs are delivered via parenteral routes because of the absorption barriers in the gastrointestinal (GI) tract such as enzymatic degradation by proteases and low permeability acrossthe...... biological membranes. To overcome these barriers, different formulation strategies for oral delivery of biomacromolecules have been proposed, including lipid based formulations and polymer-based particulate drug delivery systems (DDS). The aim of this review is to summarize the existing knowledge about oral...... delivery of peptide/protein drugs and to provide an overview of formulationand characterization strategies. For a better understanding of the challenges in oral delivery of peptide/protein drugs, the composition of GI fluids and the digestion processes of different kinds of excipients in the GI tract...

  12. Power System Aggregate Load Area Modelling by Particle Swarm Optimization

    Institute of Scientific and Technical Information of China (English)

    Jian-Lin Wei; Ji-Hong Wang; Q.H.Wu; Nan Lu

    2005-01-01

    This paper presents a new approach for deriving a power system aggregate load area model (ALAM). In this approach, an equivalent area load model is derived to represent the load characters for a particular area load of a power system network. The Particle Swarm Optimization (PSO) method is employed to identify the unknown parameters of the generalised system, ALAM, based on the system measurement directly using a one-step scheme. Simulation studies are carried out for an IEEE 14-Bus power system and an IEEE 57-Bus power system. Simulation results show that the ALAM can represent the area load characters accurately under different operational conditions and at different power system states.

  13. Plutonium Immobilization Project System Design Description for Can Loading System

    Energy Technology Data Exchange (ETDEWEB)

    Kriikku, E.

    2001-02-15

    The purpose of this System Design Description (SDD) is to specify the system and component functions and requirements for the Can Loading System and provide a complete description of the system (design features, boundaries, and interfaces), principles of operation (including upsets and recovery), and the system maintenance approach. The Plutonium Immobilization Project (PIP) will immobilize up to 13 metric tons (MT) of U.S. surplus weapons usable plutonium materials.

  14. Marine Origin Polysaccharides in Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Matias J. Cardoso

    2016-02-01

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

  15. Water delivery in the Early Solar System

    CERN Document Server

    Dvorak, Rudolf; Süli, Áron; Sándor, Zsolt; Galiazzo, Mattia; Pilat-Lohinger, Elke

    2015-01-01

    As part of the national scientific network 'Pathways to Habitable Worlds' the delivery of water onto terrestrial planets is a key question since water is essential for the development of life as we know it. After summarizing the state of the art we show some first results of the transport of water in the early Solar System for scattered main belt objects. Hereby we investigate the questions whether planetesimals and planetesimal fragments which have gained considerable inclination due to the strong dynamical interactions in the main belt region around 2 AU can be efficient water transporting vessels. The Hungaria asteroid group is the best example that such scenarios are realistic. Assuming that the gas giants and the terrestrial planets are already formed, we monitor the collisions of scattered small bodies containing water (in the order of a few percent) with the terrestrial planets. Thus we are able to give a first estimate concerning the respective contribution of such bodies to the actual water content i...

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

    Science.gov (United States)

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

    2010-01-01

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

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

    Science.gov (United States)

    Park, Kinam

    2014-09-28

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

  18. Pharmacokinetics of formulated tenoxicam transdermal delivery systems.

    Science.gov (United States)

    Kim, Taekyung; Kang, Eunyoung; Chun, Inkoo; Gwak, Hyesun

    2008-01-01

    To investigate the feasibility of developing a new tenoxicam transdermal delivery system (TDS), the pharmacokinetics of tenoxicam from various formulated TDS were evaluated and compared with values following oral administration of tenoxicam and with application of a piroxicam plaster (Trast) marketed in Korea. Based on previous in-vitro study results, a mixture of diethylene glycol monoethyl ether (DGME) and propylene glycol monolaurate (PGML) (40:60) was used as a vehicle, and caprylic acid, capric acid, lauric acid, oleic acid or linoleic acid (each at 3%) was added as an enhancer. Triethanolamine (5%) was used as a solubilizer, and Duro-Tak 87-2510 as a pressure-sensitive adhesive. Among these fatty acids used for the formulation of tenoxicam TDS, caprylic acid showed the greatest enhancing effect; the area under the plasma concentration-time profile (AUC) decreased in the order of caprylic acid>linoleic acid>or=oleic acid>lauric acid>capric acid. Compared with oral administration, maximum plasma concentration (Cmax) was significantly lower, and time to reach Cmax (Tmax) delayed with all formulated tenoxicam TDS. All formulated TDS resulted in a lower AUC than with the oral formulation, except for TDS containing caprylic acid, although the difference was statistically significant only with capric acid. The AUC for all the formulated tenoxicam TDS was significantly higher than that of the piroxicam plaster; TDS with caprylic acid increased AUC 8.53-fold compared with the piroxicam plaster. Even though the Tmax of tenoxicam TDS was not significantly different from that of the piroxicam plaster, Cmax was higher; formulations containing caprylic acid and linoleic acid increased Cmax by 7.39- and 8.76-fold, respectively. In conclusion, a formulation containing 1.5 mL DGME-PGML (40:60) with 3% caprylic acid and 5% triethanolamine mixed with 6 g Duro-Tak 87-2510 could be a good candidate for developing a new tenoxicam TDS to maintain a comparable extent of absorption

  19. Emulgel Formulation: Novel Approach for Topical Drug Delivery System

    OpenAIRE

    Habeeba Basheer; Krishnakumar, K.; Dineshkumar B.

    2016-01-01

    Topical drug delivery has been used for centuries for the treatment of local skin disorders. Drugs applied to the skin for their local action include antiseptics, antifungal agents, skin emollients, and protectants. On the other hand, topical delivery system increases the contact time and mean resident time of drug. Many advantages of gels a major limitation is in the delivery of hydrophobic drugs. So to overcome this limitation an emulsion based approach is being used. When gels and emulsion...

  20. An Efficient Diffusion Load Balancing Algorithm in Distributed System

    Directory of Open Access Journals (Sweden)

    Rafiqul Z. Khan

    2014-07-01

    Full Text Available In distributed computing system some nodes are very fast and some are slow and during the computation many fast nodes become idle or under loaded while the slow nodes become over loaded due to the uneven distribution of load in the system. In distributed system, the most common important factor is the information collection about loads on different nodes. The success of load balancing algorithm depends on how quickly the information about the load in the system is collected by a node willing to transfer or accept load. In this paper we have shown that the number of communication overheads depends on the number of overloaded nodes present in the domain of an under loaded nodes and vice-versa. We have also shown that communication overhead for load balancing is always fairly less than KN but in worst case our algorithm’s complexity becomes equal to KN.

  1. The impact of a preloaded intraocular lens delivery system on operating room efficiency in routine cataract surgery

    Science.gov (United States)

    Jones, Jason J; Chu, Jeffrey; Graham, Jacob; Zaluski, Serge; Rocha, Guillermo

    2016-01-01

    Purpose The aim of this study was to evaluate the operational impact of using preloaded intraocular lens (IOL) delivery systems compared with manually loaded IOL delivery processes during routine cataract surgeries. Methods Time and motion data, staff and surgery schedules, and cost accounting reports were collected across three sites located in the US, France, and Canada. Time and motion data were collected for manually loaded IOL processes and preloaded IOL delivery systems over four surgery days. Staff and surgery schedules and cost accounting reports were collected during the 2 months prior and after introduction of the preloaded IOL delivery system. Results The study included a total of 154 routine cataract surgeries across all three sites. Of these, 77 surgeries were performed using a preloaded IOL delivery system, and the remaining 77 surgeries were performed using a manual IOL delivery process. Across all three sites, use of the preloaded IOL delivery system significantly decreased mean total case time by 6.2%–12.0% (P<0.001 for data from Canada and the US and P<0.05 for data from France). Use of the preloaded delivery system also decreased surgeon lens time, surgeon delays, and eliminated lens touches during IOL preparation. Conclusion Compared to a manual IOL delivery process, use of a preloaded IOL delivery system for cataract surgery reduced total case time, total surgeon lens time, surgeon delays, and eliminated IOL touches. The time savings provided by the preloaded IOL delivery system provide an opportunity for sites to improve routine cataract surgery throughput without impacting surgeon or staff capacity. PMID:27382245

  2. Recent advancements in erythrocytes, platelets, and albumin as delivery systems.

    Science.gov (United States)

    Xu, Peipei; Wang, Ruju; Wang, Xiaohui; Ouyang, Jian

    2016-01-01

    In the past few years, nanomaterial-based drug delivery systems have been applied to enhance the efficacy of therapeutics and to alleviate negative effects through the controlled delivery of targeting and releasing agents. However, few drug carriers can achieve high targeting efficacy, even when targeting modalities and surface markers are introduced. Immunological problems have also limited their wide applications. Biological drug delivery systems, such as erythrocytes, platelets, and albumin, have been extensively investigated because of their unique properties. In this review, erythrocytes, platelets, and albumin are described as efficient drug delivery systems. Their properties, applications, advantages, and limitations in disease treatment are explained. This review confirms that these systems can be used to facilitate a specific, biocompatible, and smart drug delivery.

  3. Controlled drug delivery systems towards new frontiers in patient care

    CERN Document Server

    Rossi, Filippo; Masi, Maurizio

    2016-01-01

    This book offers a state-of-the-art overview of controlled drug delivery systems, covering the most important innovative applications. The principles of controlled drug release and the mechanisms involved in controlled release are clearly explained. The various existing polymeric drug delivery systems are reviewed, and new frontiers in material design are examined in detail, covering a wide range of polymer modification techniques. The concluding chapter is a case study focusing on use of a drug-eluting stent. The book is designed to provide the reader with a complete understanding of the mechanisms and design of controlled drug delivery systems, and to this end includes numerous step-by-step tutorials. It illustrates how chemical engineers can advance medical care by designing polymeric delivery systems that achieve either temporal or spatial control of drug delivery and thus ensure more effective therapy that eliminates the potential for both under-and overdosing.

  4. Mucoadhesive and thermogelling systems for vaginal drug delivery.

    Science.gov (United States)

    Caramella, Carla M; Rossi, Silvia; Ferrari, Franca; Bonferoni, Maria Cristina; Sandri, Giuseppina

    2015-09-15

    This review focuses on two formulation approaches, mucoadhesion and thermogelling, intended for prolonging residence time on vaginal mucosa of medical devices or drug delivery systems, thus improving their efficacy. The review, after a brief description of the vaginal environment and, in particular, of the vaginal secretions that strongly affect in vivo performance of vaginal formulations, deals with the above delivery systems. As for mucoadhesive systems, conventional formulations (gels, tablets, suppositories and emulsions) and novel drug delivery systems (micro-, nano-particles) intended for vaginal administration to achieve either local or systemic effect are reviewed. As for thermogelling systems, poly(ethylene oxide-propylene oxide-ethylene oxide) copolymer-based and chitosan-based formulations are discussed as thermogelling systems. The methods employed for functional characterization of both mucoadhesive and thermogelling drug delivery systems are also briefly described.

  5. Naringenin-loaded solid lipid nanoparticles: preparation, controlled delivery, cellular uptake, and pulmonary pharmacokinetics.

    Science.gov (United States)

    Ji, Peng; Yu, Tong; Liu, Ying; Jiang, Jie; Xu, Jie; Zhao, Ying; Hao, Yanna; Qiu, Yang; Zhao, Wenming; Wu, Chao

    2016-01-01

    /v) was screened as a cryoprotectant. Fourier transform infrared spectroscopy, differential scanning calorimetry, and powder X-ray diffraction studies confirmed that the drug was encapsulated into SLNs in an amorphous form. The lyophilized powder was stable at both refrigeration (4°C) and ambient temperature (25°C) for 3 months, and the MTT assay demonstrated that the SLNs were nontoxic. The cellular uptake of fluorescein isothiocyanate-labeled SLNs in A549 cells was highly time dependent over a period of 3 hours, while the pharmacokinetic study in Sprague Dawley rats showed that the relative bioavailability of NRG-SLNs was 2.53-fold greater than that of NRG suspension after pulmonary administration. This study shows that SLNs offer a promising pulmonary delivery system to increase the bioavailability of the poorly water-soluble drug NRG.

  6. Naringenin-loaded solid lipid nanoparticles: preparation, controlled delivery, cellular uptake, and pulmonary pharmacokinetics

    Directory of Open Access Journals (Sweden)

    Ji P

    2016-03-01

    size of 98 nm, a polydispersity index of 0.258, a zeta potential of -31.4 mV, a total drug content of 9.76 mg, an EE of 79.11%, and a cumulative drug release of 80% in 48 hours with a sustained profile. In addition, 5% mannitol (w/v was screened as a cryoprotectant. Fourier transform infrared spectroscopy, differential scanning calorimetry, and powder X-ray diffraction studies confirmed that the drug was encapsulated into SLNs in an amorphous form. The lyophilized powder was stable at both refrigeration (4°C and ambient temperature (25°C for 3 months, and the MTT assay demonstrated that the SLNs were nontoxic. The cellular uptake of fluorescein isothiocyanate-labeled SLNs in A549 cells was highly time dependent over a period of 3 hours, while the pharmacokinetic study in Sprague Dawley rats showed that the relative bioavailability of NRG-SLNs was 2.53-fold greater than that of NRG suspension after pulmonary administration. This study shows that SLNs offer a promising pulmonary delivery system to increase the bioavailability of the poorly water-soluble drug NRG.Keywords: naringenin, solid lipid nanoparticles, group contribution method, sustained profile, instillation technology, MTT, cellular uptake, pulmonary pharmacokinetics

  7. Application of Design Expert for the investigation of capsaicin-loaded microemulsions for transdermal delivery.

    Science.gov (United States)

    Duangjit, Sureewan; Chairat, Wisuta; Opanasopit, Praneet; Rojanarata, Theerasak; Ngawhirunpat, Tanasait

    2016-09-01

    Our previous study reported that the Design Expert® Software showed a beneficial role in the development of microemulsions (ME) for transdermal drug delivery. To fully confirm the reproducibility and the reliability of simultaneous optimal ME formulations, the optimal ME formulations predicted by the Design Expert® Software were experimentally formulated and verified for their skin permeability. Ternary phase diagrams were used to predict the optimal ME area, and the ME formulations selected from outside this area were considered as candidate ME systems. Our ME systems were formulated with isopropyl myristate (IPM) as the oil phase, cocamide diethanolamine (DEA) as the surfactant, ethanol as a co-surfactant and water as the aqueous phase. The droplet size, size distribution, electrical conductivity, pH, drug content and skin permeability of the candidate ME systems were monitored. Our findings indicated that the skin permeability of the optimal ME and all of the candidate ME formulations was significantly greater than that of the commercial capsaicin (CAP) product. Our study succeeded in predicting and developing the ME systems for the transdermal delivery of CAP. The simplex lattice design used in this study is experimentally useful for the development of pharmaceutical formulations.

  8. Lactoferrin-modified PEGylated liposomes loaded with doxorubicin for targeting delivery to hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Wei MY

    2015-08-01

    Full Text Available Minyan Wei,1,2 Xiucai Guo,1,3 Liuxiao Tu,1 Qi Zou,1 Qi Li,1 Chenyi Tang,1 Bao Chen,1 Yuehong Xu,1 Chuanbin Wu1 1Department of Pharmaceutics, School of Pharmaceutical Sciences, Sun Yat-sen University, 2Department of Pharmaceutics, School of Pharmaceutical Sciences, Guangzhou Medical University, 3Department of Pharmacy, 12th People’s Hospital of Guangzhou City, Guangzhou, People’s Republic of China Abstract: Lactoferrin (Lf is a potential-targeting ligand for hepatocellular carcinoma (HCC cells because of its specific binding with asialoglycoprotein receptor (ASGPR. In this present work, a doxorubicin (DOX-loaded, Lf-modified, polyethylene glycol (PEGylated liposome (Lf-PLS system was developed, and its targeting effect and antitumor efficacy to HCC was also explored. The DOX-loaded Lf-PLS system had spherical or oval vesicles, with mean particle size approximately 100 nm, and had an encapsulation efficiency of 97%. The confocal microscopy and flow cytometry indicated that the cellular uptake of Lf-PLS was significantly higher than that of PEGylated liposome (PLS in ASGPR-positive cells (P<0.05 but not in ASGPR-negative cells (P>0.05. Cytotoxicity assay by MTT demonstrated that DOX-loaded Lf-PLS showed significantly stronger antiproliferative effects on ASGPR-positive HCC cells than did PLS without the Lf modification (P<0.05. The in vivo antitumor studies on male BALB/c nude mice bearing HepG2 xenografts demonstrated that DOX-loaded Lf-PLS had significantly stronger antitumor efficacy compared with PLS (P<0.05 and free DOX (P<0.05. All these results demonstrated that a DOX-loaded Lf-PLS might have great potential application for HCC-targeting therapy. Keywords: asialoglycoprotein receptor, immunoliposome, PEGylated modification, post-insertion, hepatic cancer, active targeting

  9. GASTRORETENTIVE DRUG DELIVERY SYSTEM: STOMACH SPECIFIC MUCOADHESIVE TABLET

    OpenAIRE

    Siddhapara Mihir; Tikare Vijay; Ramana MV; Sutariya Bhavesh; Vaghasiya Bhavesh

    2011-01-01

    The current article focuses on the principles of mucoadhesive drug delivery systems based on adhesion to biological surfaces that are covered by mucus. Bioadhesion can be defined as the process by which a natural or a synthetic polymer can adhere to a biological substrate. When the biological substrate is a mucosal layer then the phenomena is known as mucoadhesion. Drug actions can be improved by developing new drug delivery systems, such as the mucoadhesive system. These systems remain in cl...

  10. Methods and metrics challenges of delivery-system research

    Directory of Open Access Journals (Sweden)

    Alexander Jeffrey A

    2012-03-01

    Full Text Available Abstract Background Many delivery-system interventions are fundamentally about change in social systems (both planned and unplanned. This systems perspective raises a number of methodological challenges for studying the effects of delivery-system change--particularly for answering questions related to whether the change will work under different conditions and how the change is integrated (or not into the operating context of the delivery system. Methods The purpose of this paper is to describe the methodological and measurement challenges posed by five key issues in delivery-system research: (1 modeling intervention context; (2 measuring readiness for change; (3 assessing intervention fidelity and sustainability; (4 assessing complex, multicomponent interventions; and (5 incorporating time in delivery-system models to discuss recommendations for addressing these issues. For each issue, we provide recommendations for how research may be designed and implemented to overcome these challenges. Results and conclusions We suggest that a more refined understanding of the mechanisms underlying delivery-system interventions (treatment theory and the ways in which outcomes for different classes of individuals change over time are fundamental starting points for capturing the heterogeneity in samples of individuals exposed to delivery-system interventions. To support the research recommendations outlined in this paper and to advance understanding of the "why" and "how" questions of delivery-system change and their effects, funding agencies should consider supporting studies with larger organizational sample sizes; longer duration; and nontraditional, mixed-methods designs. A version of this paper was prepared under contract with the Agency for Healthcare Research and Quality (AHRQ, US Department of Health and Human Services for presentation and discussion at a meeting on "The Challenge and Promise of Delivery System Research," held in Sterling, VA, on

  11. A Molecular Communication System Model for Particulate Drug Delivery Systems.

    Science.gov (United States)

    Chahibi, Youssef; Pierobon, Massimiliano; Song, Sang Ok; Akyildiz, Ian F

    2013-12-01

    The goal of a drug delivery system (DDS) is to convey a drug where the medication is needed, while, at the same time, preventing the drug from affecting other healthy parts of the body. Drugs composed of micro- or nano-sized particles (particulate DDS) that are able to cross barriers which prevent large particles from escaping the bloodstream are used in the most advanced solutions. Molecular communication (MC) is used as an abstraction of the propagation of drug particles in the body. MC is a new paradigm in communication research where the exchange of information is achieved through the propagation of molecules. Here, the transmitter is the drug injection, the receiver is the drug delivery, and the channel is realized by the transport of drug particles, thus enabling the analysis and design of a particulate DDS using communication tools. This is achieved by modeling the MC channel as two separate contributions, namely, the cardiovascular network model and the drug propagation network. The cardiovascular network model allows to analytically compute the blood velocity profile in every location of the cardiovascular system given the flow input by the heart. The drug propagation network model allows the analytical expression of the drug delivery rate at the targeted site given the drug injection rate. Numerical results are also presented to assess the flexibility and accuracy of the developed model. The study of novel optimization techniques for a more effective and less invasive drug delivery will be aided by this model, while paving the way for novel communication techniques for Intrabody communication networks.

  12. DEVELOPMENT AND EVALUATION OF ENZYMATICALY TRIGGERED MULTIPARTICULATE COLON TARGETED DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Mohapatra Santosh K

    2011-02-01

    Full Text Available The most critical challenge in oral colon specific drug delivery approach is to preserve the formulation during its passage through the stomach and about first six meters of the small intestine. Microbial enzyme-triggering mechanisms seem to be promising to provide more reliable colonic delivery .The objective of the present study was to develop biodegradable colon targeted multiparticulate system by using guar gum. In this study drug (Budesonide loaded pellets were coated with aqueous guar gum solution and subjected to In-vitro drug release studies simulating GIT with and without enzyme as well as coating properties were evaluated by SEM. In-vitro release studies indicates that drug release after 4.5 h lag time in presence of enzyme and lag time increase in absence of enzyme which indicated the enzyme triggered system for colonic release. This Multiparticulate system can be effectively used for colonic drug delivery for effective treatment of colonic diseases.

  13. 药物缓释载体负载药物方法的研究%Study on methods of drug loading into delivery carriers

    Institute of Scientific and Technical Information of China (English)

    袁君杰; 谢幼专

    2013-01-01

    药物经过合适的载体负载后,不仅能够达到缓释的目的,还能够改变药物的给药方式,以此减少给药次数,降低药物不良反应,提高药物的生物利用度.如何将药物负载到载体材料上并达到较高的载药量和包封率是决定缓释效果的关键因素之一.根据载体材料结构和药物特性选择合适的负载方法可获得具有良好缓释效果的药物缓释系统.本文回顾了药物缓释载体负载药物的几种常用方法:喷雾干燥法、乳化溶剂挥发法、自乳化溶剂扩散法、相分离法、溶液吸附法、直接填充法和化学结合等.现就药物缓释载体材料与药物的物理结合和化学结合两种方法作一综述.%Loading of drugs into appropriate delivery carrier material can not only improve their sustained and controlled release property but also alter route of administration, which prolongs dosing interval, reduces adverse reaction and improves biological availability. How to load drug into drug delivery carrier material and reach high drug loading capacity and encapsulation rate is critical for determining efficacy of drug sustained release. Selecting appropriate drug loading method based on the structure of delivery carrier material and properties of drugs can obtain a drug delivery system with good sustained release efficacy. This article presents a general summary of several common loading methods of drugs into delivery material, including spray drying method, emulsion solvent evaporation method, spontaneous emulsion solvent diffusion method, phase separation method, solution absorption method, direct filling method, chemical combination, and so on. Now the methods of combining drugs with drug delivery carrier material by physical combination and chemical combination are reviewed.

  14. Optical diagnostics integrated with laser spark delivery system

    Science.gov (United States)

    Yalin, Azer; Willson, Bryan; Defoort, Morgan; Joshi, Sachin; Reynolds, Adam

    2008-09-02

    A spark delivery system for generating a spark using a laser beam is provided, and includes a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. The laser delivery assembly further includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. Other embodiments use a fiber laser to generate a spark. Embodiments of the present invention may be used to create a spark in an engine. Yet other embodiments include collecting light from the spark or a flame resulting from the spark and conveying the light for diagnostics. Methods of using the spark delivery systems and diagnostic systems are provided.

  15. Polymers and formulation strategies of nanofibrous systems for drug delivery application and tissue engineering.

    Science.gov (United States)

    Sebe, I; Kállai-Szabó, B; Zelkó, R; Szabó, D

    2015-01-01

    During the last decade, the formulation of nanofibrous materials loaded with different drugs for biomedical applications has evoked considerable interest. The large specific surface area, the special micro- and macrostructure of fiber mats, the possibility for gradual release and site-specific local delivery of the active compounds lead to cytotoxicity decrease and enhancement of the therapeutic effect of drugs and implants. The present review details the different spinning techniques applied for the design of micro- and nanofibrous drug delivery systems. It furthermore deals with the use of various polymers that are capable for the formation of fiber scaffolds of various biomedical applications.

  16. An Overview on Osmotic Controlled Drug Delivery System

    Directory of Open Access Journals (Sweden)

    Thummar A

    2013-06-01

    Full Text Available This paper reviews constructed drug delivery systems applying osmotic principles for controlled drugrelease from the formulation. Osmotic devices which are tablets coated with walls of controlled porosityare the most promising strategy based systems for controlled drug delivery. In contrast to commontablets, these pumps provide constant (zero order drug release rate. When these systems are exposed towater, low levels of water soluble additive is leached from polymeric material i.e. semipermeablemembrane and drug releases in a controlled manner over an extended period of time. The main clinicalbenefits of oral osmotic drug delivery system are their ability to improve treatment tolerability andpatient compliance. These advantages are mainly driven by the capacity to deliver drugs in a sustainedmanner, independent of the drug chemical properties, of the patient’s physiological factors or followingfood intake. This review brings out the theoretical concept of drug delivery, history, advantages anddisadvantages of the delivery systems, types of oral osmotic drug delivery systems, factors affecting thedrug delivery system and marketed products.

  17. Thiolated polymers as mucoadhesive drug delivery systems.

    Science.gov (United States)

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

    2017-03-30

    Mucoadhesion is the process of binding a material to the mucosal layer of the body. Utilising both natural and synthetic polymers, mucoadhesive drug delivery is a method of controlled drug release which allows for intimate contact between the polymer and a target tissue. It has the potential to increase bioavailability, decrease potential side effects and offer protection to more sensitive drugs such as proteins and peptide based drugs. The thiolation of polymers has, in the last number of years, come to the fore of mucoadhesive drug delivery, markedly improving mucoadhesion due to the introduction of free thiol groups onto the polymer backbone while also offering a more cohesive polymeric matrix for the slower and more controlled release of drug. This review explores the concept of mucoadhesion and the recent advances in both the polymers and the methods of thiolation used in the synthesis of mucoadhesive drug delivery devices. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. A Dynamic Load Balancing Mechanism for Distributed Systems

    Institute of Scientific and Technical Information of China (English)

    蓝有然

    1996-01-01

    It is desirable in a distributed system to have the system load balanced evenly among the nodes so that the mean job response time is minimized.In this paper,we present a dynamic load balancing mechanism(DLB).It adopts a cntralized approach and is network topology independent.The DLB mechanism employs a set of threscholds which are automatically adjusted as the system load changes.It also provides a simple mechanism for the system to switch between periodic and instantaneous load balancing policies with ease.The performance of the proposed algorithm is evaluated by intensive simulations for various parameters.Te simulation results show that the mean job response time in a system implementing DLB algorithm is significantly lower than the same system without load balancings.Furthermore,compared with a previously proposed algorithm,DLB algorithm demonstrates improved performance,especially when the system is heavily loaded and the load is unevenly distributed.

  19. A combined loading system integrated with portable winch and polyethylene chutes for loading of timber products

    Directory of Open Access Journals (Sweden)

    H. Hulusi Acar

    2016-01-01

    Full Text Available Truck loading operation is an important task during timber production operations in forestry. In Turkey, approximately 50 million timbers/logs are being produced per year, and then they are loaded into the logging trucks. The timber/logs are transported over the forest roads with an average of one million roundtrips. However, the traditional loading methods using manpower are mostly performed while some part is done by using loading machines which can be very costly and risky. This study aims developing a combined loading system in which heavy logs are loaded into logging trucks by pulling them by a log-line powered by a portable crane within the chute system. The slope of the log-line from ground to logging truck varied between 1% and 25%. Within the each work cycle of loading operation, only one log was loaded by pulling with portable crane. The average loading time was found as 161.8 seconds per cycle, in which 67% of the time was spent on pulling the log into the logging truck. The results indicated that the average pulling speed with crane power was 840.4 m/hr and productivity was calculated as 4.94 m3/hr. The result on system speed and productivity indicated close relations with results from previous studies. The hydraulic grapple loader or cranes are widely used and common loading machines, but they cannot be efficiently used in forestry operations, especially ones having a low timber productivity rate or having low economic value timber. In these conditions, loading methods that are cost efficient and do not require higher production rate should be employed. Therefore, a combined loading system introduced in this study can be a feasible solution for loading operations in those cases. Furthermore, it is believed that this loading system integrated with a portable crane can be cost efficient and time saving solution, as well as ergonomic and safe method in the field.

  20. Wind loads on solar energy systems, mounted on flat roofs

    NARCIS (Netherlands)

    Geurts, C.P.W.; Bentum, C.A. van; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads on solar energy systems, which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The resu

  1. Wind loads on solar energy systems, mounted on flat roofs

    NARCIS (Netherlands)

    Geurts, C.P.W.; Bentum, C.A. van; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads on solar energy systems, which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The resu

  2. Novel Musculoskeletal Loading and Assessment System

    Science.gov (United States)

    Downs, Meghan E.

    2017-01-01

    Ground based and ISS (International Space Station) exercise research have shown that axial loading via two-point loading at the shoulders and load quality (i.e. consistent load and at least 1:1 concentric to eccentric ratio) are extremely important to optimize musculoskeletal adaptations to resistance exercise. The Advanced Resistance Exercise Device (ARED) is on ISS now and is the "state of the art" for resistance exercise capabilities in microgravity; however, the ARED is far too large and power consuming for exploration vehicles. The single cable exercise device design selected for MPCV (Multi-Purpose Crew Vehicle), does not readily allow for the two-point loading at the shoulders.

  3. NIOSOMES: A ROLE IN TARGETED DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Soumya Singh

    2013-02-01

    Full Text Available Niosomes are non-ionic surfactant vesicles inclosing an aqueous phase and a wide range of molecules could be encapsulated within aqueous spaces of lipid membrane vesicles. They are microscopic lamellar structures formed on the admixture of a non-ionic surfactant, cholesterol and phosphate with subsequent hydration in aqueous media. Niosomes belongs to novel drug delivery system which offers a large number of advantages over other conventional and vesicular delivery systems. Namely they are the targeted drug delivery system which showing reduction of dose, stability and compatibility of non-ionic surfactants, easy modification, delayed clearance, suitability for a wide range of Active Pharmaceutical Agents.

  4. Isoniazid loaded gelatin-cellulose whiskers nanoparticles for controlled drug delivery applications

    Indian Academy of Sciences (India)

    MANDIP SARMAH; ANOWAR HUSSAIN; ANAND RAMTEKE; TARUN K MAJI

    2016-08-01

    Natural polymers like gelatin have been used as a potential drug carrier for controlled delivery applications due to their various advantages over synthetic polymers. Cellulose Whiskers (CWs) have the capacity to form strong hydrogen bonds which help in controlling the release of drug and also provide goodstrength to the drug carrier. In this report, CWs were prepared from filter paper cellulose by acid hydrolysis. Also, attempt was made to prepare gelatin-CWs nanoparticles by desolvation method using an anti-tuberculosis drug, isoniazid and a crosslinker glutaraldehyde (GA). The CWs and gelatin-CWs nanoparticles were characterized by X-ray diffractometry (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The effect of CWs on gelatin nanoparticlesover 8-hour period was measured in swelling studies. Efficiency of drug loading and subsequent release of isoniazid in buffer solutions at pH 1.2 (0.1N HCl) and pH 7.4 (phosphate buffer) were studied. Cytotoxicity study showed less toxicity for gelatin-CWs nanoparticles.

  5. Fabrication of Progesterone-Loaded Nanofibers for the Drug Delivery Applications in Bovine

    Science.gov (United States)

    Karuppannan, Chitra; Sivaraj, Mehnath; Kumar, J. Ganesh; Seerangan, Rangasamy; Balasubramanian, S.; Gopal, Dhinakar Raj

    2017-02-01

    Progesterone is a potent drug for synchronization of the estrus and ovulation cycles in bovine. At present, the estrus cycle of bovine is controlled by the insertion of progesterone-embedded silicone bands. The disadvantage of nondegradable polymer inserts is to require for disposal of these bands after their use. The study currently focuses on preparation of biodegradable progesterone-incorporated nanofiber for estrus synchronization. Three different concentrations (1.2, 1.9, and 2.5 g) of progesterone-impregnated nanofibers were fabricated using electrospinning. The spun membrane were characterized by scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and Fourier transform infrared spectroscopy. Uniform surface morphology, narrow size distribution, and interaction between progesterone and zein were confirmed by SEM. FTIR spectroscopy indicated miscibility and interaction between zein and progesterone. X-ray analysis indicated that the size of zein crystallites increased with progesterone content in nanofibers. Significant differences in thermal behavior of progesterone-impregnated nanofiber were observed by DSC. Cell viability studies of progesterone-loaded nanofiber were examined using MTT assay. In vitro release experiment is to identify the suitable progesterone concentration for estrus synchronization. This study confirms that progesterone-impregnated nanofibers are an ideal vehicle for progesterone delivery for estrus synchronization of bovines.

  6. Nanoembedded Microparticles for Stabilization and Delivery of Drug-Loaded Nanoparticles.

    Science.gov (United States)

    Bohr, Adam; Water, Jorrit; Beck-Broichsitter, Moritz; Yang, Mingshi

    2015-01-01

    Nanoparticle-based pharmaceutical products are currently finding their way onto the market as a popular strategy to improve the therapeutic efficacy of numerous drugs, hereunder medications for a targeted treatment of severe diseases (e.g., cancer). Drug-loaded polymer and lipid nanoparticles are typically produced via solvent-based methods and result in colloidal suspensions, which often suffer from physical and chemical instability (e.g., formation of aggregates) resulting in loss of functionality. There are various ways to stabilize such nanoparticle-based formulations including addition of ionic materials to provide electrostatic repulsion or polymer materials forming a steric barrier between the particles. However, for long-term stability often water needs to be removed to obtain a dry product. For this purpose atomization-based techniques such as spray-drying and spray freeze-drying are frequently used to remove water from the nanoparticle suspensions and to form tailored powder products (e.g., nanoembedded microparticles (NEMs)). NEMs provide an excellent vehicle for both stabilization of nanoparticles and delivery of the nanoparticles to their intended site of action. Excipients such as sugars and biocompatible polymers are used to prepare the surrounding, stabilizing matrix. Further, these "Trojan" vehicles are compatible with a wide range of therapeutic molecules, nanocarriers and applications for different routes of administration. The preparation, properties and stability of these NEMs are described in this review and their application and future development are discussed.

  7. Mechanical valve assembly for xenon 133 gas delivery systems

    Energy Technology Data Exchange (ETDEWEB)

    Round, W.H. (Royal Brisbane Hospital, Herston (Australia))

    Some gas delivery systems used in pulmonary ventilation scanning are unable to satisfactorily supply /sup 133/Xe gas to bed-ridden patients. A mechanical gas valve assembly to control the flow of gas in such systems was constructed. A commercially produced /sup 133/Xe gas delivery system when fitted with the new assembly was able to ventilate almost all patients whereas previously this could be achieved with approximately only 50% of patients.

  8. Improvement of different vaccine delivery systems for cancer therapy

    Directory of Open Access Journals (Sweden)

    Safaiyan Shima

    2011-01-01

    Full Text Available Abstract Cancer vaccines are the promising tools in the hands of the clinical oncologist. Many tumor-associated antigens are excellent targets for immune therapy and vaccine design. Optimally designed cancer vaccines should combine the best tumor antigens with the most effective immunotherapy agents and/or delivery strategies to achieve positive clinical results. Various vaccine delivery systems such as different routes of immunization and physical/chemical delivery methods have been used in cancer therapy with the goal to induce immunity against tumor-associated antigens. Two basic delivery approaches including physical delivery to achieve higher levels of antigen production and formulation with microparticles to target antigen-presenting cells (APCs have demonstrated to be effective in animal models. New developments in vaccine delivery systems will improve the efficiency of clinical trials in the near future. Among them, nanoparticles (NPs such as dendrimers, polymeric NPs, metallic NPs, magnetic NPs and quantum dots have emerged as effective vaccine adjuvants for infectious diseases and cancer therapy. Furthermore, cell-penetrating peptides (CPP have been known as attractive carrier having applications in drug delivery, gene transfer and DNA vaccination. This review will focus on the utilization of different vaccine delivery systems for prevention or treatment of cancer. We will discuss their clinical applications and the future prospects for cancer vaccine development.

  9. Designing and assessing a sustainable networked delivery (SND) system: hybrid business-to-consumer book delivery case study.

    Science.gov (United States)

    Kim, Junbeum; Xu, Ming; Kahhat, Ramzy; Allenby, Braden; Williams, Eric

    2009-01-01

    We attempted to design and assess an example of a sustainable networked delivery (SND) system: a hybrid business-to-consumer book delivery system. This system is intended to reduce costs, achieve significant reductions in energy consumption, and reduce environmental emissions of critical local pollutants and greenhouse gases. The energy consumption and concomitant emissions of this delivery system compared with existing alternative delivery systems were estimated. We found that regarding energy consumption, an emerging hybrid delivery system which is a sustainable networked delivery system (SND) would consume 47 and 7 times less than the traditional networked delivery system (TND) and e-commerce networked delivery system (END). Regarding concomitant emissions, in the case of CO2, the SND system produced 32 and 7 times fewer emissions than the TND and END systems. Also the SND system offer meaningful economic benefit such as the costs of delivery and packaging, to the online retailer, grocery, and consumer. Our research results show that the SND system has a lot of possibilities to save local transportation energy consumption and delivery costs, and reduce environmental emissions in delivery system.

  10. Lipid nanoparticles as drug/gene delivery systems to the retina.

    Science.gov (United States)

    del Pozo-Rodríguez, Ana; Delgado, Diego; Gascón, Alicia R; Solinís, Maria Ángeles

    2013-03-01

    This review highlights the application of lipid nanoparticles (Solid Lipid Nanoparticles, Nanostructured Lipid Carriers, or Lipid Drug Conjugates) as effective drug/gene delivery systems for retinal diseases. Most drug products for ocular disease treatment are marketed as eye drop formulations but, due to ocular barriers, the drug concentration in the retina hardly ever turns out to be effective. Up to this date, several delivery systems have been designed to deliver drugs to the retina. Drug delivery strategies may be classified into 3 groups: noninvasive techniques, implants, and colloidal carriers. The best known systems for drug delivery to the posterior eye are intravitreal implants; in fact, some of them are being clinically used. However, their long-term accumulation might impact the patient's vision. On the contrary, colloidal drug delivery systems (microparticles, liposomes, or nanoparticles) can be easily administered in a liquid form. Nanoparticular systems diffuse rapidly and are better internalized in ocular tissues than microparticles. In comparison with liposomes, nanoparticles have a higher loading capacity and are more stable in biological fluids and during storage. In addition, their capacity to adhere to the ocular surface and interact with the endothelium makes these drug delivery systems interesting as new therapeutic tools in ophthalmology. Within the group of nanoparticles, those composed of lipids (Solid Lipid Nanoparticles, Nanostructred Lipid Carriers, and Lipid Drug Conjugates) are more biocompatible, easy to produce at large scale, and they may be autoclaved or sterilized. The present review summarizes scientific results that evidence the potential application of lipid nanoparticles as drug delivery systems for the retina and also as nonviral vectors in gene therapy of retina disorders, although much more effort is still needed before these lipidic systems could be available in the market.

  11. Folic acid conjugated magnetic drug delivery system for controlled release of doxorubicin

    Science.gov (United States)

    Andhariya, Nidhi; Upadhyay, Ramesh; Mehta, Rasbindu; Chudasama, Bhupendra

    2013-01-01

    Targeting tumors by means of their vascular endothelium is a promising strategy, which utilizes targets that are easily accessible, stable, and do not develop resistance against therapeutic agents. Folate receptor is a highly specific tumor marker, frequently over expressed in cancer tumors. In the present study, an active drug delivery system, which can effectively target cancer cells by means of folate receptor-mediated endocytosis, have ability to escape from opsonization and capability of magnetic targeting to withstand the drag force of the body fluid have been designed and synthesized. The core of the drug delivery system is of mono-domain magnetic particles of magnetite. Magnetite nanoparticles are shielded with PEG, which prevents their phagocytosis by reticuloendothelial system. These PEG shielded magnetite nanoparticles are further decorated with an antitumor receptor—folic acid and loaded with an antineoplastic agent doxorubicin. An in vitro drug loading and release kinetics study reveals that the drug delivery system can take 52 % of drug load and can release doxorubicin over a sustained period of 7 days. The control and sustained release over a period of several days may find its practical utilities in chemotherapy where frequent dosing is not possible.

  12. Folic acid conjugated magnetic drug delivery system for controlled release of doxorubicin

    Energy Technology Data Exchange (ETDEWEB)

    Andhariya, Nidhi, E-mail: nidhiandhariya@gmail.com [Thapar University, School of Physics and Materials Science (India); Upadhyay, Ramesh [Charotar University of Science and Technology, P.D. Patel Institute of Applied Sciences (India); Mehta, Rasbindu [Maharaja Krishnakumarsinhji Bhavnagar University, Department of Physics (India); Chudasama, Bhupendra, E-mail: bnchudasama@gmail.com [Thapar University, School of Physics and Materials Science (India)

    2013-01-15

    Targeting tumors by means of their vascular endothelium is a promising strategy, which utilizes targets that are easily accessible, stable, and do not develop resistance against therapeutic agents. Folate receptor is a highly specific tumor marker, frequently over expressed in cancer tumors. In the present study, an active drug delivery system, which can effectively target cancer cells by means of folate receptor-mediated endocytosis, have ability to escape from opsonization and capability of magnetic targeting to withstand the drag force of the body fluid have been designed and synthesized. The core of the drug delivery system is of mono-domain magnetic particles of magnetite. Magnetite nanoparticles are shielded with PEG, which prevents their phagocytosis by reticuloendothelial system. These PEG shielded magnetite nanoparticles are further decorated with an antitumor receptor-folic acid and loaded with an antineoplastic agent doxorubicin. An in vitro drug loading and release kinetics study reveals that the drug delivery system can take 52 % of drug load and can release doxorubicin over a sustained period of 7 days. The control and sustained release over a period of several days may find its practical utilities in chemotherapy where frequent dosing is not possible.

  13. Comparison of Deterministic and Probabilistic Radial Distribution Systems Load Flow

    Science.gov (United States)

    Gupta, Atma Ram; Kumar, Ashwani

    2017-08-01

    Distribution system network today is facing the challenge of meeting increased load demands from the industrial, commercial and residential sectors. The pattern of load is highly dependent on consumer behavior and temporal factors such as season of the year, day of the week or time of the day. For deterministic radial distribution load flow studies load is taken as constant. But, load varies continually with a high degree of uncertainty. So, there is a need to model probable realistic load. Monte-Carlo Simulation is used to model the probable realistic load by generating random values of active and reactive power load from the mean and standard deviation of the load and for solving a Deterministic Radial Load Flow with these values. The probabilistic solution is reconstructed from deterministic data obtained for each simulation. The main contribution of the work is: - Finding impact of probable realistic ZIP load modeling on balanced radial distribution load flow. - Finding impact of probable realistic ZIP load modeling on unbalanced radial distribution load flow. - Compare the voltage profile and losses with probable realistic ZIP load modeling for balanced and unbalanced radial distribution load flow.

  14. Encapsulation of Polymethoxyflavones in Citrus Oil Emulsion-Based Delivery Systems.

    Science.gov (United States)

    Yang, Ying; Zhao, Chengying; Chen, Jingjing; Tian, Guifang; McClements, David Julian; Xiao, Hang; Zheng, Jinkai

    2017-03-01

    The purpose of this work was to elucidate the effects of citrus oil type on polymethoxyflavone (PMF) solubility and on the physicochemical properties of PMF-loaded emulsion-based delivery systems. Citrus oils were extracted from mandarin, orange, sweet orange, and bergamot. The major constituents were determined by GC/MS: sweet orange oil (97.4% d-limonene); mandarin oil (72.4% d-limonene); orange oil (67.2% d-limonene); and bergamot oil (34.6% linalyl acetate and 25.3% d-limonene). PMF-loaded emulsions were fabricated using 10% oil phase (containing 0.1% w/v nobiletin or tangeretin) and 90% aqueous phase (containing 1% w/v Tween 80) using high-pressure homogenization. Delivery systems prepared using mandarin oil had the largest mean droplet diameters (386 or 400 nm), followed by orange oil (338 or 390 nm), bergamot oil (129 or 133 nm), and sweet orange oil (122 or 126 nm) for nobiletin- or tangeretin-loaded emulsions, respectively. The optical clarity of the emulsions increased with decreasing droplet size due to reduced light scattering. The viscosities of the emulsions (with or without PMFs) were similar (1.3 to 1.4 mPa·s), despite appreciable differences in oil phase viscosity. The loading capacity and encapsulation efficiency of the emulsions depended on carrier oil type, with bergamot oil giving the highest loading capacity. In summary, differences in the composition and physical characteristics of citrus oils led to PMF-loaded emulsions with different encapsulation and physicochemical characteristics. These results will facilitate the rational design of emulsion-based delivery systems for encapsulation of PMFs and other nutraceuticals in functional foods and beverages.

  15. Manufacturing of a Secretoneurin Drug Delivery System with Self-Assembled Protamine Nanoparticles by Titration

    Science.gov (United States)

    Scheicher, Bernhard; Lorenzer, Cornelia; Gegenbauer, Katrin; Partlic, Julia; Andreae, Fritz; Kirsch, Alexander H.; Rosenkranz, Alexander R.; Werzer, Oliver

    2016-01-01

    Since therapeutic peptides and oligonucleotides are gathering interests as active pharmaceutical ingredients (APIs), nanoparticulate drug delivery systems are becoming of great importance. Thereby, the possibility to design drug delivery systems according to the therapeutic needs of APIs enhances clinical implementation. Over the last years, the focus of our group was laid on protamine-oligonucleotide-nanoparticles (so called proticles), however, the possibility to modify the size, zeta potential or loading efficiencies was limited. Therefore, at the present study we integrated a stepwise addition of protamine (titration) into the formation process of proticles loaded with the angiogenic neuropeptide secretoneurin (SN). A particle size around 130 nm was determined when proticles were assembled by the commonly used protamine addition at once. Through application of the protamine titration process it was possible to modify and adjust the particle size between approx. 120 and 1200 nm (dependent on mass ratio) without influencing the SN loading capacity. Dynamic light scattering pointed out that the difference in particle size was most probably the result of a secondary aggregation. Initially-formed particles of early stages in the titration process aggregated towards bigger assemblies. Atomic-force-microscopy images also revealed differences in morphology along with different particle size. In contrast, the SN loading was only influenced by the applied mass ratio, where a slight saturation effect was observable. Up to 65% of deployed SN could be imbedded into the proticle matrix. An in-vivo biodistribution study (i.m.) showed a retarded distribution of SN from the site of injection after the application of a SN-proticle formulation. Further, it was demonstrated that SN loaded proticles can be successfully freeze-dried and resuspended afterwards. To conclude, the integration of the protamine titration process offers new possibilities for the formulation of proticles in

  16. Catastrophe model and its experimental verification of static loading rock system under impact load

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    According to the catastrophe model for impact buckling of static loading structures, a new catastrophe model for impact loading failure of a static loading rock system was established, and one dimension (1D) catastrophe model was analyzed. The analysis results indicate that the furcation collection where catastrophe may take place is not only decided by mechanical system itself but also relates to exterior loading, which is different from the results obtained under mono-static loading where the bifurcation collection is only determined by mechanics of the system itself and has nothing to do with exterior loading. In addition, the corresponding 1D coupled static-dynamic loading experiment is designed to verify the analysis results of catastrophe model The test is done with Instron 1342 electroservo controlled testing system, in which medium strain rate is caused by monotony rising dynamic load. The parameters are obtained combining theoretical model with experiment. The experimental and theoretical curves of critical dynamic load vs static load are rather coincided, thus the new model is proved to be correct.

  17. The Research Progress of Targeted Drug Delivery Systems

    Science.gov (United States)

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

    2017-06-01

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

  18. Elastin-like recombinamers as smart drug delivery systems.

    Science.gov (United States)

    Javier Arias, F; Santos, Mercedes; Ibáñez-Fonseca, Arturo; Piña, Maria Jesús; Serrano, Sofía

    2016-01-31

    Drug delivery systems that are able to control site and rate release of bioactive molecules are of particular interest for tissue therapy. Systems comprising biocompatible materials that can respond to environmental stimuli include elastin-like recombinamers (ELRs), a class of proteinaceous polymers bioinspired by natural elastin, which are especially useful as advanced drug delivery systems in the biomedical field. This review brings together information concerning different versions of ELR-based delivery systems that allow targeted delivery. ELR-drug systems in their monomeric form as well as drug encapsulation by nanoparticle-forming ELRs will be reviewed, focusing later on these drug carriers in which smart release is triggered by pH or temperature with a particular interest on cancer treatments. Systems for controlled drug release based on depots and hydrogels that act both as a support and reservoir in which drugs can be stored will be described, and their applications in drug delivery discussed. Finally, smart drug-delivery systems not based on ELRs, including those comprising proteins, synthetic polymers and non-polymeric systems, will also be briefly discussed.

  19. Microneedles as a Delivery System for Gene Therapy

    Directory of Open Access Journals (Sweden)

    Wei eChen

    2016-05-01

    Full Text Available Gene delivery systems can be divided to two major types: vector-based (either viral vector or non-viral vector and physical delivery technologies. Many physical carriers, such as electroporation, gene gun, ultrasound start to be proved to have the potential to enable gene therapy. A relatively new physical delivery technology for gene delivery consists of microneedles (MNs, which has been studied in many fields and for many molecule types and indications. Microneedles can penetrate the stratum corneum, which is the main barrier for drug delivery through the skin with ease of administration and without significant pain. Many different kinds of MNs, such as metal MNs, coated MNs, dissolving MNs have turned out to be promising in gene delivery. In this review, we discussed the potential as well as the challenges of utilizing MNs to deliver nucleic acids for gene therapy. We also proposed that a combination of MNs and other gene delivery approaches may lead to a better delivery system for gene therapy.

  20. Formulation and evaluation of an anti-epileptic drug-loaded microemulsion for nose to brain delivery

    Directory of Open Access Journals (Sweden)

    Kawtikwar P

    2009-01-01

    Full Text Available The aim of the present study was to formulate an anti-epileptic drug-loaded microemulsion for nose-to-brain delivery. The oil system evaluated for the preparation of a stable microemulsion was iso-propyl myristate. A non-ionic surfactant like Tween 80 was used with polyethylene glycol 400 as a co-surfactant. A pseudoternary phase diagram for various proportions of S mix :oil was constructed by the water titration method. The effect of changing concentration of alcohol as a co-surfactant was also studied. The t-phase diagram shows that the water consumption capacity of the system was increased as the surfactant concentration was increased. It was also found that as the concentration of the alcohol was increased, the viscosity of the microemulsion decreased. After the identification of the microemulsion region, the composition of the microemulsion was fixed at oil 9-10%, S mix 35-40% and water 45-50%. The formulated microemulsion was evaluated for various parameters like pH, conductivity, zeta potential, viscosity and in vitro drug diffusion studies. All the evaluation parameters showed satisfactory results. Using this microemulsion, the solubility of valproic acid was increased from 1.29 to 36 mg/ml. Diffusion studies have shown a lag period of 45 min. Thirteen percent drug diffusion was achieved in 3 h. The prepared microemulsion was stable at 40°C and 75% relative humidity.

  1. Educational and Career Guidance for Adults: Delivery System Alternatives.

    Science.gov (United States)

    Darkenwald, Gordon G.

    1980-01-01

    Discusses the need for guidance and information services to help adults make educational and career choices, from an organizational and administrative perspective. Major innovations are needed in educational delivery systems for the adult public. Federal legislation can help. (JAC)

  2. Buccal Transmucosal Delivery System of Enalapril for Improved ...

    African Journals Online (AJOL)

    Methods: Transmucosal drug delivery systems of enalapril maleate were formulated as buccal films by solvent casting .... Table1: Composition of transmucosal buccal films of enalapril maleate ... was fixed to the central shaft using an adhesive.

  3. Optical Systems For High Power Laser Beam Delivery

    Science.gov (United States)

    Durville, Frederic M.; Cilia, D.

    1989-03-01

    During the pst fifteen years, pwerful lasers have been developed for industrial applications such as cutting, piercing, welding, engraving, etc... Convenient and reliable delivery systems are still needed to widen their field of application.

  4. Novel Nanostructured Solid Materials for Modulating Oral Drug Delivery from Solid-State Lipid-Based Drug Delivery Systems

    National Research Council Canada - National Science Library

    Dening, Tahnee J; Rao, Shasha; Thomas, Nicky; Prestidge, Clive A

    2016-01-01

    Lipid-based drug delivery systems (LBDDS) have gained significant attention in recent times, owing to their ability to overcome the challenges limiting the oral delivery of poorly water-soluble drugs...

  5. Customer participation in service production and delivery system

    OpenAIRE

    Sridhar, M. S.

    1998-01-01

    Highlights significance of designing service delivery system, explains the integral role of customer in service production process, stresses the importance of customer-organisation interface, lists important ingredients of service package to be considered while designing customer interface, enumerates various dimensions of customer interface which can be positively made use of in design of service production and delivery system, discusses various ways and means of inducing and enhancing custo...

  6. MULTIPARTICULATE DRUG DELIVERY SYSTEM: PELLETIZATION THROUGH EXTRUSION AND SPHERONIZATION

    OpenAIRE

    Anshuli Sharma; Sandhya Chaurasia

    2013-01-01

    Pharmaceutical invention and research are increasingly focusing on delivery systems which enhance desirable therapeutic objectives while minimising side effects. Recent trends indicate that multiparticulate drug delivery systems are especially suitable for achieving controlled or delayed release oral formulations with low risk of dose dumping, flexibility of blending to attain different release patterns as well as reproducible and short gastric residence time. Pelletization is a technique use...

  7. Polysaccharides-based polyelectrolyte nanoparticles as protein drugs delivery system

    Energy Technology Data Exchange (ETDEWEB)

    Shu Shujun; Sun Lei; Zhang Xinge, E-mail: zhangxinge@nankai.edu.cn [Nankai University, Key Laboratory of Functional Polymer Materials Ministry of Education, Institute of Polymer Chemistry (China); Wu Zhongming [Tianjin Medical University, Metabolic Diseases Hospital (China); Wang Zhen; Li Chaoxing, E-mail: lcx@nankai.edu.cn [Nankai University, Key Laboratory of Functional Polymer Materials Ministry of Education, Institute of Polymer Chemistry (China)

    2011-09-15

    Polysaccharides-based nanoparticles were prepared by synthesized quaternized chitosan and dextran sulfate through simple ionic-gelation self-assembled method. Introduction of quaternized groups was intended to increase water solubility of chitosan and make the nanoparticles have broader pH sensitive range which can remain more stable in physiological pH and decrease the loss of protein drugs caused by the gastric cavity. The load of BSA was affected by molecular parameter, i.e., degree of substitution, and average molecular weight of quaternized chitosan, as well as concentration of BSA. Fast release occurred in phosphate buffer solution (pH 7.4) while the release was slow in hydrochloric acid (pH 1.4). The drug release mechanism is Fickian diffusion through release kinetics analysis. Cell uptake demonstrated nanoparicles can internalize into Caco-2 cells, which suggested that nanoparticles had good biocompatibility. No significant conformation change was noted for the released BSA in comparison with native BSA using circular dichroism spectroscopy. This kind of novel composite nanoparticles may be a promising delivery system for oral protein and peptide drugs.

  8. 14 CFR 25.397 - Control system loads.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Control system loads. 25.397 Section 25.397... STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.397 Control system...) and to be reacted at the attachment of the control system to the control surface horn. (b)...

  9. Heavy Load Rollers in Logistic Systems

    Directory of Open Access Journals (Sweden)

    B. Künne

    2003-01-01

    Full Text Available Wheels with polyurethane bandages are in common use in logistic systems with friction gear actuation. Many research projects have studied the mechanical construction of these heavy load wheels. The studies have been theoretical as well as experimental. Research interests at the department of machine elements include the wear in the presence of intermediate material on the contact area between the bandage surface and the contact surface on which the wheel rolls off. This problem, which is observed when examining this tribochemical system, has not been studied before. Within this project both one-phase intermediate materials such as sand, water, cutting-cooling-emulsion, metal splinters and two-phase intermediate materials such as sand/water and combinations of the latter were taken into consideration. In addition, the exposure of the bandage hardness, the cross linking agent of the polyurethane, the mechanical stress, and the slip are observed. The analysis of the experimental results indicates that friction gear actuators can be constructed abrasion-optimised, taking into account special interfering effects in the form of intermediate materials in the contact area.

  10. Model for determining and optimizing delivery performance in industrial systems

    Directory of Open Access Journals (Sweden)

    Fechete Flavia

    2017-01-01

    Full Text Available Performance means achieving organizational objectives regardless of their nature and variety, and even overcoming them. Improving performance is one of the major goals of any company. Achieving the global performance means not only obtaining the economic performance, it is a must to take into account other functions like: function of quality, delivery, costs and even the employees satisfaction. This paper aims to improve the delivery performance of an industrial system due to their very low results. The delivery performance took into account all categories of performance indicators, such as on time delivery, backlog efficiency or transport efficiency. The research was focused on optimizing the delivery performance of the industrial system, using linear programming. Modeling the delivery function using linear programming led to obtaining precise quantities to be produced and delivered each month by the industrial system in order to minimize their transport cost, satisfying their customers orders and to control their stock. The optimization led to a substantial improvement in all four performance indicators that concern deliveries.

  11. Biodegradable mesoporous delivery system for biomineralization precursors

    Science.gov (United States)

    Yang, Hong-ye; Niu, Li-na; Sun, Jin-long; Huang, Xue-qing; Pei, Dan-dan; Huang, Cui; Tay, Franklin R

    2017-01-01

    Scaffold supplements such as nanoparticles, components of the extracellular matrix, or growth factors have been incorporated in conventional scaffold materials to produce smart scaffolds for tissue engineering of damaged hard tissues. Due to increasing concerns on the clinical side effects of using large doses of recombinant bone-morphogenetic protein-2 in bone surgery, it is desirable to develop an alternative nanoscale scaffold supplement that is not only osteoinductive, but is also multifunctional in that it can perform other significant bone regenerative roles apart from stimulation of osteogenic differentiation. Because both amorphous calcium phosphate (ACP) and silica are osteoinductive, a biodegradable, nonfunctionalized, expanded-pore mesoporous silica nanoparticle carrier was developed for loading, storage, and sustained release of a novel, biosilicification-inspired, polyamine-stabilized liquid precursor phase of ACP for collagen biomineralization and for release of orthosilicic acid, both of which are conducive to bone growth. Positively charged poly(allylamine)-stabilized ACP (PAH-ACP) could be effectively loaded and released from nonfunctionalized expanded-pore mesoporous silica nanoparticles (pMSN). The PAH-ACP released from loaded pMSN still retained its ability to infiltrate and mineralize collagen fibrils. Complete degradation of pMSN occurred following unloading of their PAH-ACP cargo. Because PAH-ACP loaded pMSN possesses relatively low cytotoxicity to human bone marrow-derived mesenchymal stem cells, these nanoparticles may be blended with any osteoconductive scaffold with macro- and microporosities as a versatile scaffold supplement to enhance bone regeneration. PMID:28182119

  12. Biological studies of matrix metalloproteinase sensitive drug delivery systems

    DEFF Research Database (Denmark)

    Johansen, Pia Thermann

    due to severe side effects as a result of drug distribution to healthy tissues. To enhance ecacy of treatment and improve life quality of patients, tumor specific drug delivery strategies, such as liposome encapsulated drugs, which accumulate in tumor tissue, has gained increased attention. Several...... for delivery of drugs to specific tissues or cells utilizing biological knowledge of cancer tissue is getting increased attention. In this thesis a novel matrix metalloproteinase-2 (MMP-2) sensitive poly-ethylene glycol (PEG) coated liposomal drug delivery system for treatment of cancer was developed...... the use of MMP- 2 as a trigger for liposomal activation in tumor tissue. Thus, this new strategy provides a promising system for specific delivery of encapsulated drugs and controlled release in tumor tissues, resulting in enhanced drug bioavailability and decreased systemic side effects. In addition, we...

  13. Solvothermal synthesis of cobalt ferrite nanoparticles loaded on multiwalled carbon nanotubes for magnetic resonance imaging and drug delivery.

    Science.gov (United States)

    Wu, Huixia; Liu, Gang; Wang, Xue; Zhang, Jiamin; Chen, Yu; Shi, Jianlin; Yang, Hong; Hu, He; Yang, Shiping

    2011-09-01

    Multiwalled carbon nanotube (MWCNT)/cobalt ferrite (CoFe(2)O(4)) magnetic hybrids were synthesized by a solvothermal method. The reaction temperature significantly affected the structure of the resultant MWCNT/CoFe(2)O(4) hybrids, which varied from 6nm CoFe(2)O(4) nanoparticles uniformly coated on the nanotubes at 180°C to agglomerated CoFe(2)O(4) spherical particles threaded by MWCNTs and forming necklace-like nanostructures at 240°C. Based on the superparamagnetic property at room temperature and high hydrophilicity, the MWCNT/CoFe(2)O(4) hybrids prepared at 180°C (MWCNT/CoFe(2)O(4)-180) were further investigated for biomedical applications, which showed a high T(2) relaxivity of 152.8 Fe mM(-1)s(-1) in aqueous solutions, a significant negative contrast enhancement effect on cancer cells and, more importantly, low cytotoxicity and negligible hemolytic activity. The anticancer drug doxorubicin (DOX) can be loaded onto the hybrids and subsequently released in a sustained and pH-responsive way. The DOX-loaded hybrids exhibited notable cytotoxicity to HeLa cancer cells due to the intracellular release of DOX. These results suggest that MWCNT/CoFe(2)O(4)-180 hybrids may be used as both effective magnetic resonance imaging contrast agents and anticancer drug delivery systems for simultaneous cancer diagnosis and chemotherapy. Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  14. Biodegradable Magnetic Silica@Iron Oxide Nanovectors with Ultra-Large Mesopores for High Protein Loading, Magnetothermal Release, and Delivery

    KAUST Repository

    Omar, Haneen

    2016-11-29

    The delivery of large cargos of diameter above 15 nm for biomedical applications has proved challenging since it requires biocompatible, stably-loaded, and biodegradable nanomaterials. In this study, we describe the design of biodegradable silica-iron oxide hybrid nanovectors with large mesopores for large protein delivery in cancer cells. The mesopores of the nanomaterials spanned from 20 to 60 nm in diameter and post-functionalization allowed the electrostatic immobilization of large proteins (e.g. mTFP-Ferritin, ~ 534 kDa). Half of the content of the nanovectors was based with iron oxide nanophases which allowed the rapid biodegradation of the carrier in fetal bovine serum and a magnetic responsiveness. The nanovectors released large protein cargos in aqueous solution under acidic pH or magnetic stimuli. The delivery of large proteins was then autonomously achieved in cancer cells via the silica-iron oxide nanovectors, which is thus a promising for biomedical applications.

  15. Effects Of Polylactic Acid Coating and Compression Load on the Delivery of Protein and Steroid from HA Ceramic Devices.

    Science.gov (United States)

    Benghuzzi, Hamed; Tucci, Michelle A; Ibrahim, Jamil

    2015-01-01

    Density variations, due to particle size and time and temperature of sintering, affect the delivery profile of substances from ceramic delivery devices. This investigation was conducted to study the effect of polylactic acid (PLA) impregnation on the porosity of hydroxyapatite (HA) capsules by studying the delivery rate of bovine serum albumin (BSA) and testosterone (TE). HA capsules were fabricated by cold compressing calcined particles at 1000, 3000, and 5000 lbs. Each group was subdivided into PLA-impregnated and non-PLA impregnated capsules. Each capsule was loaded with either 40 mg of TE (impregnated or nonimpregnated with PLA polymer) or BSA. Data obtained in this study suggest that: (1) PLA impregnation of HA ceramic capsules decreases the rate of release of drugs from the ceramic reservoir, (2) Physiochemical characteristics of the drugs to be delivered is an instrumental key in the sustained release profiles, (3) Compression load of HA reservoirs is a key factor in predicting the duration and level of sustained delivery, and (4) Polymer coating of HA ceramic capsules reduces the pore size, as well as, blocking some of the pores on the surface.

  16. A targeted drug delivery system based on dopamine functionalized nano graphene oxide

    Science.gov (United States)

    Masoudipour, Elham; Kashanian, Soheila; Maleki, Nasim

    2017-01-01

    The cellular targeting property of a biocompatible drug delivery system can widely increase the therapeutic effect against various diseases. Here, we report a dopamine conjugated nano graphene oxide (DA-nGO) carrier for cellular delivery of the anticancer drug, Methotrexate (MTX) into DA receptor positive human breast adenocarcinoma cell line. The material was characterized using scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy and UV-vis spectroscopy. Furthermore, the antineoplastic action of MTX loaded DA-nGO against DA receptor positive and negative cell lines were explored. The results presented in this article demonstrated that the application of DA functionalized GO as a targeting drug carrier can improve the drug delivery efficacy for DA receptor positive cancer cell lines and promise future designing of carrier conjugates based on it.

  17. Dexamethasone-loaded reconstitutable charged polymeric (PLGA)n -b-bPEI micelles for enhanced nuclear delivery of gene therapeutics.

    Science.gov (United States)

    Mishra, Deepa; Kang, Han Chang; Cho, Hana; Bae, You Han

    2014-06-01

    This study investigates the potential of dexamethasone (Dex) to enhance the nuclear accumulation and subsequent gene expression of plasmid DNA (pDNA) delivered using a charged polymeric micelle-based gene delivery system. (PLGA)n -b-bPEI25kDa block copolymers are synthesized and used to prepare Dex-loaded cationic micelles (DexCM). After preparing DexCM/pDNA complexes, bPEI1.8kDa is coated on the complexes using a Layer-by-Layer (LbL) technique to construct DexCM/pDNA/bPEI1.8kDa complexes (i.e., LbL-DexCM polyplexes) that are 100-180 nm in diameter and have a zeta potential of 30-40 mV. In MCF7 cells, LbL-DexCM polyplexes cause 3-13-fold higher transfection efficiencies compared to LbL-CM polyplexes and show negligible cytotoxicity. LbL-DexCM3 polyplexes induce much higher nuclear delivery of pDNA compared to LbL-CM3 polyplexes. These results suggest that Dex-loaded polyplexes could be used in gene and drug delivery applications to increase nuclear accumulation of therapeutic payloads, further leading to a decrease in the dose of the drug and gene necessary to achieve equivalent therapeutic effects.

  18. Development of a Controlled Release of Salicylic Acid Loaded Stearic Acid-Oleic Acid Nanoparticles in Cream for Topical Delivery

    Directory of Open Access Journals (Sweden)

    J. O. Woo

    2014-01-01

    Full Text Available Lipid nanoparticles are colloidal carrier systems that have extensively been investigated for controlled drug delivery, cosmetic and pharmaceutical applications. In this work, a cost effective stearic acid-oleic acid nanoparticles (SONs with high loading of salicylic acid, was prepared by melt emulsification method combined with ultrasonication technique. The physicochemical properties, thermal analysis and encapsulation efficiency of SONs were studied. TEM micrographs revealed that incorporation of oleic acid induces the formation of elongated spherical particles. This observation is in agreement with particle size analysis which also showed that the mean particle size of SONs varied with the amount of OA in the mixture but with no effect on their zeta potential values. Differential scanning calorimetry analysis showed that the SONs prepared in this method have lower crystallinity as compared to pure stearic acid. Different amount of oleic acid incorporated gave different degree of perturbation to the crystalline matrix of SONs and hence resulted in lower degrees of crystallinity, thereby improving their encapsulation efficiencies. The optimized SON was further incorporated in cream and its in vitro release study showed a gradual release for 24 hours, denoting the incorporation of salicylic acid in solid matrix of SON and prolonging the in vitro release.

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

    Science.gov (United States)

    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.

  20. Budesonide-Loaded Guar Gum Microspheres for Colon Delivery: Preparation, Characterization and in Vitro/in Vivo Evaluation

    Directory of Open Access Journals (Sweden)

    Ye Liu

    2015-01-01

    Full Text Available A novel budesonide (BUD colon delivery release system was developed by using a natural polysaccharide, guar gum. The rigidity of the microspheres was induced by a chemical cross-linking method utilizing glutaraldehyde as the cross-linker. The mean particle size of the microspheres prepared was found to be 15.21 ± 1.32 µm. The drug loading and entrapment efficiency of the formulation were 17.78% ± 2.31% and 81.6% ± 5.42%, respectively. The microspheres were spherical in shape with a smooth surface, and the size was uniform. The in vitro release profiles indicated that the release of BUD from the microspheres exhibited a sustained release behavior. The model that fitted best for BUD released from the microspheres was the Higuchi kinetic model with a correlation coefficient r = 0.9993. A similar phenomenon was also observed in a pharmacokinetic study. The prolongation of the half-life (t1/2, enhanced residence time (mean residence time, MRT and decreased total clearance (CL indicated that BUD microspheres could prolong the acting time of BUD in vivo. In addition, BUD guar gum microspheres are thought to have the potential to maintain BUD concentration within target ranges for a long time, decreasing the side effects caused by concentration fluctuation, ensuring the efficiency of treatment and improving patient compliance by reducing dosing frequency. None of the severe signs, like the appearance of epithelial necrosis and the sloughing of epithelial cells, were detected.

  1. Adaptive Control System for Autonomous Helicopter Slung Load Operations

    DEFF Research Database (Denmark)

    Bisgaard, Morten; la Cour-Harbo, Anders; Bendtsen, Jan Dimon

    2010-01-01

    system on the helicopter that measures the position of the slung load. The controller is a combined feedforward and feedback scheme for simultaneous avoidance of swing excitation and active swing damping. Simulations and laboratory flight tests show the effectiveness of the combined control system......This paper presents design and verification of an estimation and control system for a helicopter slung load system. The estimator provides position and velocity estimates of the slung load and is designed to augment existing navigation in autonomous helicopters. Sensor input is provided by a vision......, yielding significant load swing reduction compared to the baseline controller....

  2. Voltage-Sensitive Load Controllers for Voltage Regulation and Increased Load Factor in Distribution Systems

    DEFF Research Database (Denmark)

    Douglass, Philip James; Garcia-Valle, Rodrigo; Østergaard, Jacob

    2014-01-01

    consumption which can be mapped to temperature setpoint offsets of thermostat controlled loads. In networks where a lower voltage level corresponds to high system load (and vice versa), this controller acts to regulate voltage and increase the load factor. Simulations are conducted on low- and medium-voltage......This paper presents a novel controller design for controlling appliances based on local measurements of voltage. The controller finds the normalized voltage deviation accounting for the sensitivity of voltage measurements to appliance state. The controller produces a signal indicating desired power...... distribution systems with residential loads including voltage-sensitive water heaters. In low-voltage systems, the results of the simulations show the controller to be effective at reducing the extremes of voltage and increasing the load factor while respecting end-use temperature constraints. In medium-voltage...

  3. A REVIEW ON FLOATING TYPE GASTRORETENTIVE DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Pallavi Pal

    2012-04-01

    Full Text Available Oral controlled release delivery systems are programmed to deliver the drug in predictable time frame that will increase the efficacy and minimize the adverse effects and increase the bioavailability of drugs. Oral route is considered mostnatural, uncomplicated, convenient and safe due to its ease of administration, patient acceptance, and cost-effective manufacturing process.Floating Drug delivery system are designed to prolong the gastric residence time after oral administration, at particular site and controlling the release of drug especially useful for achieving controlled plasma level a swell as improving bioavailability Several approaches are currently being used to prolong the GRT, including floating drug delivery systems (FDDS, also known as hydrodynamically balanced systems (HBS, swelling and expanding systems, high-density systems, and other delayed gastric emptying devices.

  4. Colloidal drug delivery systems: current status and future directions.

    Science.gov (United States)

    Garg, Tarun; Rath, Goutam; Goyal, Amit Kumar

    2015-01-01

    In this paper, we provide an overview an extensive range of colloidal drug delivery systems with special focus on vesicular and particulates systems that are being used in research or might be potentially useful as carriers systems for drug or active biomolecules or as cell carriers with application in the therapeutic field. We present some important examples of commercially available drug delivery systems with applications in research or in clinical fields. This class of systems is widely used due to excellent drug targeting, sustained and controlled release behavior, higher entrapment efficiency of drug molecules, prevention of drug hydrolysis or enzymatic degradation, and improvement of therapeutic efficacy. These characteristics help in the selection of suitable carrier systems for drug, cell, and gene delivery in different fields.

  5. Strategies For Assessing Delivery System Innovations.

    Science.gov (United States)

    McGlynn, Elizabeth A; McClellan, Mark

    2017-03-01

    Driven by evidence of continuing gaps in health care quality and efficiency and inspired by the emergence of new value-based payment models, both large and small health care organizations are developing and deploying a wide range of care delivery innovations. But how can decision makers in these organizations determine if the innovations really improve service delivery, patient experience, clinical outcomes, or costs? Organization leaders need appropriate, timely evidence to inform their decision making. In this article we describe a range of approaches to evaluating innovations and pose key questions about the validity of the results. We highlight a specific type of evaluation approach-the stepped wedge design-because it can balance the need for internal and external validity with the ability to generate timely results. We elaborate on three key steps in the innovation assessment phase (identifying the target population, describing baseline performance, and documenting the components of the innovation) that are useful for both organizations that will generate new evidence and those using evidence generated by others. We conclude with a discussion of payer approaches for supporting health care organizations in their efforts to develop new evidence on innovations. Project HOPE—The People-to-People Health Foundation, Inc.

  6. PROBIOTIC DELIVERY SYSTEMS: APPLICATIONS, CHALLENGES AND PROSPECTIVE

    Directory of Open Access Journals (Sweden)

    Yadav Nisha R.

    2013-04-01

    Full Text Available Probiotic are bacteria that help to maintain the natural balance of the microorganism in the intestine. Probiotic is gaining its popularity as an alternate approach for the healthcare management and till now has proofed its therapeutic indication in many simple to complex diseases. Diverse mechanism of action and being a living organism are two main advantages. However there are several drawbacks also associated with this new emerging therapeutic area. Probiotic strain identification, characterization, screening, understanding its mechanism of action for particular disease which is seeking much attention. The primary aim associated with the probiotic delivery is maintaining bacteria viability during product manufacturing and during storage. Several approaches such as microencapsulation and use of suitable biocompatible material have been studied and still under continuous exploration. Along with the regulatory aspect associated with the probiotics in this review details on current research in the area of exploring indication and advancement in delivery technologies has been covered. Review concluded with rational recommendations of each aspect of probiotics.

  7. A REVIEW ON PARENTERAL CONTROLLED DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Milan Agrawal et al

    2012-10-01

    Full Text Available The parenteral administration route is the most effective and common form of delivery for active drug substances with poor bioavailability and the drugs with a narrow therapeutic index. Drug delivery technology that can reduce the total number of injection throughout the drug therapy period will be truly advantageous not only in terms of compliance, but also to improve the quality of the therapy and also may reduce the dosage frequency. Such reduction in frequency of drug dosing is achieved by the use of specific formulation technologies that guarantee the release of the active drug substance in a slow and predictable manner. The development of new injectable drug delivery system has received considerable attention over the past few years. A number of technological advances have been made in the area of parenteral drug delivery leading to the development of sophisticated systems that allow drug targeting and the sustained or controlled release of parenteral medicines.

  8. Drug delivery system based on chronobiology--A review.

    Science.gov (United States)

    Mandal, Asim Sattwa; Biswas, Nikhil; Karim, Kazi Masud; Guha, Arijit; Chatterjee, Sugata; Behera, Mamata; Kuotsu, Ketousetuo

    2010-11-01

    With the advancement in the field of chronobiology, modern drug delivery approaches have been elevated to a new concept of chronopharmacology i.e. the ability to deliver the therapeutic agent to a patient in a staggered profile. However the major drawback in the development of such delivery system that matches the circadian rhythm requires the availability of precise technology (pulsatile drug delivery). The increasing research interest surrounding this delivery system has widened the areas of pharmaceutics in particular with many more sub-disciplines expected to coexist in the near future. This review on chronopharmaceutics gives a comprehensive emphasis on potential disease targets, revisits the existing technologies in hand and also addresses the theoretical approaches to emerging discipline such as genetic engineering and target based specific molecules. With the biological prospective approaches in delivering drugs it is well understood that safer and more realistic approaches in the therapy of diseases will be achieved in the days to come.

  9. SOLID LIPID NANOPARTICLES: AN ADVANCED DRUG DELIVERY SYSTEM

    OpenAIRE

    Raghu Nandan Reddy* and Arshia Shariff

    2013-01-01

    Solid lipid nanoparticles are at the forefront of the rapidly developing field of nanotechnology with several potential applications in drug delivery, research and clinical medicine, as well as in other varied sciences. Solid lipid nanoparticle (SLN) dispersions have been proposed as a new type of colloidal drug carrier system suitable for intravenous administration. Solid lipid nanoparticles (SLNs) technology represents a promising new approach to lipophilic drug delivery. Solid lipid nanopa...

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

    DEFF Research Database (Denmark)

    Christophersen, Philip Carsten; Fano, Mathias; Saaby, Lasse;

    2015-01-01

    are summarized. Additionally, the paper provides an overview of recent studies on characterization of solid drug carriers for peptide/protein drugs, drug distribution in particles, drug release and stability in simulated GI fluids, as well as the absorption of peptide/protein drugs in cell-based models. The use......Oral drug delivery is a preferred route because of good patient compliance. However, most peptide/ protein drugs are delivered via parenteral routes because of the absorption barriers in the gastrointestinal (GI) tract such as enzymatic degradation by proteases and low permeability acrossthe...... biological membranes. To overcome these barriers, different formulation strategies for oral delivery of biomacromolecules have been proposed, including lipid based formulations and polymer-based particulate drug delivery systems (DDS). The aim of this review is to summarize the existing knowledge about oral...

  11. Novel multifunctional pH-sensitive nanoparticles loaded into microbubbles as drug delivery vehicles for enhanced tumor targeting.

    Science.gov (United States)

    Lv, Yongjiu; Hao, Lan; Hu, Wenjing; Ran, Ya; Bai, Yan; Zhang, Liangke

    2016-01-01

    This study fabricated novel multifunctional pH-sensitive nanoparticles loaded into microbubbles (PNP-MB) with the combined advantages of two excellent drug delivery vehicles, namely, pH-sensitive nanoparticles and microbubbles. As an antitumor drug, resveratrol (RES) was loaded into acetylated β-cyclodextrin nanoparticles (RES-PNP). The drug-loaded nanoparticles were then encapsulated into the internal space of the microbubbles. The characterization and morphology of this vehicle were investigated through dynamic light scattering and confocal laser scanning microscopy, respectively. In vitro drug release was performed to investigate the pH sensitivity of RES-PNP. The antitumor property of RES-loaded PNP-MB (RES-PNP-MB) was also analyzed in vivo to evaluate the antitumor effect of RES-PNP-MB. Results suggested that PNP exhibited pH sensitivity, and was successfully encapsulated into the microbubbles. RES-PNP-MB exhibit effective tumor growth suppressing in vivo. Therefore, such drug delivery vehicle should be of great attention in tumor therapy.

  12. 喷雾干燥氯诺昔康自微乳化制剂在兔体内的生物利用度%Bioavailability of Spray-dried Self-microemulsifying Drug Delivery System Loaded with Lomoxicam in Rabbits

    Institute of Scientific and Technical Information of China (English)

    宋逸婷; 孙婉瑾; 高缘; 李超

    2012-01-01

    以氯诺昔康片剂为参比制剂,考察了自制喷雾干燥氯诺昔康自微乳化制剂在兔体内的相对生物利用度.以吡罗昔康为内标,采用高效液相色谱法测定兔血浆中的氯诺昔康.6只家兔分别灌胃给予氯诺昔康的片剂或喷雾干燥自微乳化制剂,结果显示,其AUC分别为16 304和26 328 ng·h·ml-1,cmax分别为824和1788 ng/ml,tmax分别为7.0和3.0 h.配对t检验分析表明AUC和cmax具有显著性差异(P<0.05),tmax具有极显著性差异(P<0.01),自微乳化制剂的相对生物利用度为161.5%.%The relative bioavailability of spray-dried self-micoremulsifying drug delivery system (SMEDDS) loaded with lornoxicam in rabbits was investigated with lornoxicam tablets as the reference preparation. The drug concentration in rabbit plasma was determined by HPLC with piroxicam as the internal standard. The pharmacokinetics in six rabbits after ig administration of the above two preparations was investigated. The main pharmacokinetic parameters of the tables and SMEDDS were as follows: AUC 16 304 and 26 328 ng·h·ml-1, cmax 824 and 1 788 ng/ml, tmax 7.0 and 3.0 h, respectively. The results of paired t test showed that there was a significant difference (P<0.05) in AUC and cmax and a very significant difference (P<0.01) in tmax The relative bioavailability of spray-dried SMEDDS loaded with lornoxicam was 161.5%.

  13. Recent trends in protein and peptide drug delivery systems

    Directory of Open Access Journals (Sweden)

    Gupta Himanshu

    2009-01-01

    Full Text Available With the discovery of insulin in 1922, identification and commercialization of potential protein and peptide drugs have been increased. Since then, research and development to improve the means of delivering protein therapeutics to patients has begun. The research efforts have followed two basic pathways: One path focused on noninvasive means of delivering proteins to the body and the second path has been primarily aimed at increasing the biological half-life of the therapeutic molecules. The search for approaches that provide formulations that are stable, bioavailable, readily manufacturable, and acceptable to the patient, has led to major advances in the development of nasal and controlled release technology, applicable to every protein or peptide. In several limited cases, sustained delivery of peptides and proteins has employed the use of polymeric carriers. More successes have been achieved by chemical modification using amino acid substitutions, protein pegylation or glycosylation to improve the pharmacodynamic properties of certain macromolecules and various delivery systems have been developed like the prolease technology, nano-particulate and microparticulate delivery systems, and the mucoadhesive delivery of peptides. The needle and syringe remain the primary means of protein delivery. Major hurdles remain in order to overcome the combined natural barriers of drug permeability, drug stability, pharmacokinetics, and pharmacodynamics of protein therapeutics. In our present review we have tried to compile some recent advances in protein and peptide drug delivery systems.

  14. Formulation and Stability Aspects of Nanosized Solid Drug Delivery Systems.

    Science.gov (United States)

    Szabo, Peter; Zelko, Romana

    2015-01-01

    Nano drug delivery systems are considered as useful means to remedy the problems of drugs of poor solubility, permeability and bioavailability, which became one of the most troublesome questions of the pharmaceutical industry. Different types of nanosized drug delivery systems have been developed and investigated for oral administration, providing auspicious solutions for drug development. In this paper nanosized drug delivery systems intended for oral administration are discussed based on the chemical nature of the carrier of drug molecules. Lipid nanoparticles comprising solid lipid nanoparticles, improved nanostructured lipid carriers and nanostructured silica- lipid hybrid particles have become popular in the formulation of lipophilic drugs of poor oral bioavailability. Polymeric nanoparticles including nanospheres and nanocapsules and polymeric fibrous systems have also emerged as potential drug delivery systems owing to their unique structure. The feasibility of surface functionalization of mesoporous materials and gold nanoparticles enables high level of control over particle characteristics making inorganic nanoparticles an exceptional formulation approach. The authors paid particular attention to the functionality-related stability of the reviewed delivery systems.

  15. MAST Propellant and Delivery System Design Methods

    Science.gov (United States)

    Nadeem, Uzair; Mc Cleskey, Carey M.

    2015-01-01

    A Mars Aerospace Taxi (MAST) concept and propellant storage and delivery case study is undergoing investigation by NASA's Element Design and Architectural Impact (EDAI) design and analysis forum. The MAST lander concept envisions landing with its ascent propellant storage tanks empty and supplying these reusable Mars landers with propellant that is generated and transferred while on the Mars surface. The report provides an overview of the data derived from modeling between different methods of propellant line routing (or "lining") and differentiate the resulting design and operations complexity of fluid and gaseous paths based on a given set of fluid sources and destinations. The EDAI team desires a rough-order-magnitude algorithm for estimating the lining characteristics (i.e., the plumbing mass and complexity) associated different numbers of vehicle propellant sources and destinations. This paper explored the feasibility of preparing a mathematically sound algorithm for this purpose, and offers a method for the EDAI team to implement.

  16. Hydrocolloid-based nutraceutical delivery systems

    Energy Technology Data Exchange (ETDEWEB)

    Janaswamy, Srinivas; Youngren, Susanne R. (Purdue)

    2012-07-11

    Nutraceuticals are important due to their inherent health benefits. However, utilization and consumption are limited by their poor water solubility and instability at normal processing and storage conditions. Herein, we propose an elegant and novel approach for the delivery of nutraceuticals in their active form using hydrocolloid matrices that are inexpensive and non-toxic with generally recognized as safe (GRAS) status. Iota-carrageenan and curcumin have been chosen as models of hydrocolloid and nutraceutical compounds, respectively. The iota-carrageenan network maintains a stable organization after encapsulating curcumin molecules, protects them from melting and then releases them in a sustained manner. These findings lay a strong foundation for developing value-added functional and medicinal foods.

  17. Supramolecular hydrogels as drug delivery systems.

    Science.gov (United States)

    Saboktakin, Mohammad Reza; Tabatabaei, Roya Mahdavi

    2015-04-01

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

  18. Biodegradable mesoporous delivery system for biomineralization precursors

    Directory of Open Access Journals (Sweden)

    Yang HY

    2017-01-01

    Full Text Available Hong-ye Yang,1 Li-na Niu,2 Jin-long Sun,2 Xue-qing Huang,3 Dan-dan Pei,4 Cui Huang,1 Franklin R Tay5 1The State Key Laboratory Breeding Base of Basic Science of Stomatology, Key Laboratory for Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, People’s Republic of China; 2State Key Laboratory of Military Stomatology, National Clinical Research Center for Oral Diseases, Shaanxi Key Laboratory of Oral Diseases, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi’an, Shaanxi, People’s Republic of China; 3Department of Prosthodontics, Guanghua School and Hospital of Stomatology, Guangdong Key Laboratory of Stomatology, Yat-sen University, Guangzhou, Guangdong, People’s Republic of China; 4Department of Prosthodontics, College of Stomatology, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China; 5Department of Endodontics, College of Dental Medicine, Augusta University, Augusta, GA, USA Abstract: Scaffold supplements such as nanoparticles, components of the extracellular matrix, or growth factors have been incorporated in conventional scaffold materials to produce smart scaffolds for tissue engineering of damaged hard tissues. Due to increasing concerns on the clinical side effects of using large doses of recombinant bone-morphogenetic protein-2 in bone surgery, it is desirable to develop an alternative nanoscale scaffold supplement that is not only osteoinductive, but is also multifunctional in that it can perform other significant bone regenerative roles apart from stimulation of osteogenic differentiation. Because both amorphous calcium phosphate (ACP and silica are osteoinductive, a biodegradable, nonfunctionalized, expanded-pore mesoporous silica nanoparticle carrier was developed for loading, storage, and sustained release of a novel, biosilicification-inspired, polyamine-stabilized liquid precursor phase of ACP

  19. Recent trends in challenges and opportunities of Transdermal drug delivery system

    Directory of Open Access Journals (Sweden)

    P.M.Patil

    2012-03-01

    Full Text Available Drug delivery system relates to the production of a drug, its delivery medium, and the way of administration. Drug delivery systems are even used for administering nitroglycerin. Transdermal drug delivery system is the system in which the delivery of the active ingredients of the drug occurs by the means of skin. Various types of transdermal patches are used. There are various methods to enhance the transdermal drug delivery system. But using microfabricated microneedles drugs are delivered very effectively to skin patch. There has been great progress in the Transdermal drug delivery system for the delivery of different forms and our aim is to collect the information about what progressed have done in Transdermal drug delivery system and developments in Transdermal drug delivery systems in theoretical form. Also, to collect the information about the advantages and application of the Transdermal drug delivery systems.

  20. Progress in oral drug-loaded nano-system%口服纳米载药系统研究进展

    Institute of Scientific and Technical Information of China (English)

    丁志英; 张越; 刁亚茹; 池季洪; 胡玉琳

    2016-01-01

    Oral drug-loaded nano-system include nano-gel drug delivery system, nano-suspension drug delivery system, nano-particle drug delivery system, liposomes drug delivery system, nano-micelles drug delivery system, alcohol liposoms,nano-framework drug delivery system, nano-emulsions drug delivery system, nano-self assembly drug delivery system.These nano-drug delivery systems can serve as multi-functional drug carriers.They may significantly improve the physicochemical and stabilization and biological properties of the free drug, enhance the therapeutic efficiency and reduce toxic side effects.This paper reviews the recent research progress in oral drug-loaded nano-systems.%口服纳米载药系统包括纳米凝胶、纳米混悬剂、纳米粒、纳米脂质体、醇脂体、纳米胶束、纳米骨架、纳米乳和自组装体纳米释药系统。他们可通过口服,转运中药、生物药和化药,并显著改善药物分子的理化性质、稳定性和生物学性质,提高疗效,降低副作用。本文综述了口服纳米载药系统的研究进展。

  1. Preparing and Characterizing Chitosan Nanoparticles Containing Hemiscorpius lepturus Scorpion Venom as an Antigen Delivery System

    Directory of Open Access Journals (Sweden)

    Mohammadpour Dounighi, N.

    2012-11-01

    Full Text Available In recent years, chitosan nanoparticles have been studied widely for protein delivery. In this study, Hemiscorpius lepturus (HL venom was encapsulated in chitosan nanoparticles. The aim of the present work was to carry out a systematic study for preparing biocompatible and biodegradable nanoparticles for loading HL scorpion venom and to evaluate their potential as an antigen delivery system. In this study, HL venom loaded chitosan nanoparticles fabricated by ionic gelation of chitosan and tripolyphosphate and the factors which may be influenced in the preparation of nanoparticles were analyzed. Also, their physicochemical properties and in vitro release behavior were studied. The optimum encapsulation efficiency and capacity were observed when the chitosan concentration and HL venom were 2mg/ml and 500µg/ml, respectively. The HL venom loaded nanoparticles were in the size range of 130-160nm (polydispersity index values of 0.423 and exhibited the positive zeta potential. Transmission electron microscope imaging showed spherical and smooth surface of nanoparticles. The profiles of the release exhibited a burst releases about 50% in the first 4 hr and then slowed down at a constant rate. The obtained results suggested that the chitosan nanoparticles prepared in this work had the potential for antigen delivery.

  2. Formulation and characterization of lipid-based drug delivery system of raloxifene-microemulsion and self-microemulsifying drug delivery system

    Directory of Open Access Journals (Sweden)

    Hetal Thakkar

    2011-01-01

    Full Text Available Background : Raloxifene, a second-generation selective estrogen receptor modulator (SERM used to prevent osteoporosis in postmenopausal women is administered orally in the form of a tablet. The absolute bioavailability of the drug is only 2% because of extensive hepatic first-pass metabolism. Lipid-based formulations are reported to reduce the first-pass metabolism by promoting its lymphatic uptake. Materials and Methods : In the present investigation, microemulsion and Self-Microemulsifying Drug Delivery System (SMEDDS formulations of Raloxifene were prepared. The prepared formulations were characterized for drug loading, size, transparency, zeta potential, Transmission Electron Microscopy (TEM and in vitro intestinal permeability. Results : The results indicated that high drug loading, optimum size and desired zeta potential and transparency could be achieved with both SMEDDS and microemulsion. The TEM studies indicated the absence of aggregation with both the systems. The in vitro intestinal permeability results showed that the permeation of the drug from the microemulsion and SMEDDs was significantly higher than that obtained from the drug dispersion and marketed formulation. Conclusion : Lipid based formulations such as microemulsion and Self Microemulsifying drug delivery systems are expected to increase the oral bioavailability as evidenced by the increased intestinal permeation.

  3. Air-to-Water Heat Pumps With Radiant Delivery in Low-Load Homes

    Energy Technology Data Exchange (ETDEWEB)

    Backman, C.; German, A.; Dakin, B.; Springer, D.

    2013-12-01

    Space conditioning represents nearly 50% of average residential household energy consumption, highlighting the need to identify alternative cost-effective, energy-efficient cooling and heating strategies. As homes are better built, there is an increasing need for strategies that are particularly well suited for high performance, low load homes. ARBI researchers worked with two test homes in hot-dry climates to evaluate the in-situ performance of air-to-water heat pump (AWHP) systems, an energy efficient space conditioning solution designed to cost-effectively provide comfort in homes with efficient, safe, and durable operation. Two monitoring projects of test houses in hot-dry climates were initiated in 2010 to test this system. Both systems were fully instrumented and have been monitored over one year to capture complete performance data over the cooling and heating seasons. Results are used to quantify energy savings, cost-effectiveness, and system performance using different operating modes and strategies. A calibrated TRNSYS model was developed and used to evaluate performance in various climate regions. This strategy is most effective in tight, insulated homes with high levels of thermal mass (i.e. exposed slab floors).

  4. Air-to-Water Heat Pumps With Radiant Delivery in Low-Load Homes

    Energy Technology Data Exchange (ETDEWEB)

    Backman, C. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); German, A. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Dakin, B. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States); Springer, D. [Alliance for Residential Building Innovation (ARBI), Davis, CA (United States)

    2013-12-01

    Space conditioning represents nearly 50% of average residential household energy consumption, highlighting the need to identify alternative cost-effective, energy-efficient cooling and heating strategies. As homes are better built, there is an increasing need for strategies that are particularly well suited for high performance, low load homes. ARBI researchers worked with two test homes in hot-dry climates to evaluate the in-situ performance of air-to-water heat pump systems, an energy efficient space conditioning solution designed to cost-effectively provide comfort in homes with efficient, safe, and durable operation. Two monitoring projects of test houses in hot-dry climates were initiated in 2010 to test this system. Both systems were fully instrumented and have been monitored over one year to capture complete performance data over the cooling and heating seasons. Results are used to quantify energy savings, cost-effectiveness, and system performance using different operating modes and strategies. A calibrated TRNSYS model was developed and used to evaluate performance in various climate regions. This strategy is most effective in tight, insulated homes with high levels of thermal mass (i.e. exposed slab floors).

  5. A DETAILED REVIEW ON ORAL MUCOSAL DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Radha Bhati

    2012-03-01

    Full Text Available Oral mucosal drug delivery system is widely applicable as novel site for administration of drug for immediate and controlled release action by preventing first pass metabolism and enzymatic degradation due to GI microbial flora. Oral mucosal drug delivery system provides local and systemic action. In this review, attention is focused to give regarding physiology of oral mucosal including tissue permeability, barriers to permeation and route of permeation, biopharmaceutics of buccal and sublingual absorption, factors affecting drug absorption, detailed information of penetration enhancers, design of oral mucosal drug delivery system and role of mucoadhesion and various theories of bioadhesion. Evaluation techniques and selection of animal model for in-vivo studies are also discussed.

  6. ORAL MULTIPARTICULATE PULSATILE DRUG DELIVERY SYSTEMS: A REVIEW

    Directory of Open Access Journals (Sweden)

    Shaji Jessy

    2011-02-01

    Full Text Available Pulsatile drug delivery aims to release drugs in a planned pattern i.e. at appropriate time and/or at a suitable site of action. Pharmaceutical invention and research are increasingly focusing on delivery systems which enhance desirable therapeutic objectives while minimising side effects. However, in recent pharmaceutical applications involving pulsatile delivery, multiparticulate dosage forms are gaining much favour over single-unit dosage forms because of their potential benefits like predictable gastric emptying, no risk of dose dumping, flexible release patterns and increased bioavailability with less inter- and intra-subject variability. Based on these, the present review aims to study multiparticulate pulsatile delivery systems, for which the Reservoir systems with rupturable polymeric coatings and Reservoir systems with erodible polymer coatings are primarily involved in the control of release. Multiparticulate drug delivery systems provide tremendous opportunities for designing new controlled and delayed release oral formulations, thus extending the frontier of future pharmaceutical development. The development of low density floating multiparticulate pulsed-release dosage forms possessing gastric retention capabilities has also been addressed with increasing focus on the upcoming multiparticulate-pulsatile technologies being exploited on an industrial scale.

  7. Coacervate delivery systems for proteins and small molecule drugs.

    Science.gov (United States)

    Johnson, Noah R; Wang, Yadong

    2014-12-01

    Coacervates represent an exciting new class of drug delivery vehicles, developed in the past decade as carriers of small molecule drugs and proteins. This review summarizes several well-described coacervate systems, including: i) elastin-like peptides for delivery of anticancer therapeutics; ii) heparin-based coacervates with synthetic polycations for controlled growth factor delivery; iii) carboxymethyl chitosan aggregates for oral drug delivery; iv) Mussel adhesive protein and hyaluronic acid coacervates. Coacervates present advantages in their simple assembly and easy incorporation into tissue engineering scaffolds or as adjuncts to cell therapies. They are also amenable to functionalization such as for targeting or for enhancing the bioactivity of their cargo. These new drug carriers are anticipated to have broad applications and noteworthy impact in the near future.

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

    Science.gov (United States)

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

    2016-03-01

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

  9. Dendrimeric Systems and Their Applications in Ocular Drug Delivery

    Directory of Open Access Journals (Sweden)

    Burçin Yavuz

    2013-01-01

    Full Text Available Ophthalmic drug delivery is one of the most attractive and challenging research area for pharmaceutical scientists and ophthalmologists. Absorption of an ophthalmic drug in conventional dosage forms is seriously limited by physiological conditions. The use of nonionic or ionic biodegradable polymers in aqueous solutions and colloidal dosage forms such as liposomes, nanoparticles, nanocapsules, microspheres, microcapsules, microemulsions, and dendrimers has been studied to overcome the problems mentioned above. Dendrimers are a new class of polymeric materials. The unique nanostructured architecture of dendrimers has been studied to examine their role in delivery of therapeutics and imaging agents. Dendrimers can enhance drug’s water solubility, bioavailability, and biocompatibility and can be applied for different routes of drug administration successfully. Permeability enhancer properties of dendrimers were also reported. The use of dendrimers can also reduce toxicity versus activity and following an appropriate application route they allow the delivery of the drug to the targeted site and provide desired pharmacokinetic parameters. Therefore, dendrimeric drug delivery systems are of interest in ocular drug delivery. In this review, the limitations related to eye’s unique structure, the advantages of dendrimers, and the potential applications of dendrimeric systems to ophthalmology including imaging, drug, peptide, and gene delivery will be discussed.

  10. Preparation and in vivo absorption evaluation of spray dried powders containing salmon calcitonin loaded chitosan nanoparticles for pulmonary delivery

    Directory of Open Access Journals (Sweden)

    Sinsuebpol C

    2013-08-01

    prepared to have appropriate aerodynamic properties for pulmonary delivery. The developed system was able to deliver sCT via a pulmonary route into the systemic circulation. Keywords: Salmon calcitonin, chitosan, nanoparticles, mannitol, spray dried powders, pulmonary delivery

  11. Proniosomes as a carrier system for transdermal delivery of tenoxicam.

    Science.gov (United States)

    Ammar, H O; Ghorab, M; El-Nahhas, S A; Higazy, I M

    2011-02-28

    Tenoxicam is a non steroidal anti-inflammatory drug (NSAID) widely used in the treatment of rheumatic diseases and characterized by its good efficacy and less side effects compared to other NSAIDs. Its oral administration is associated with severe side effects in the gastrointestinal tract. Transdermal drug delivery has been recognized as an alternative route to oral delivery. Proniosomes offer a versatile vesicle delivery concept with the potential for drug delivery via the transdermal route. In this study, different proniosomal gel bases were prepared, characterized by light microscopy, revealing vesicular structures, and assessed for their drug entrapment efficiency, stability, their effect on in vitro drug release and ex vivo drug permeation. The lecithin-free proniosomes prepared from Tween 20:cholesterol (9:1) proved to be stable with high entrapment and release efficiencies. The in vivo behaviour of this formula was studied on male rats and compared to that of the oral market product. The investigated tenoxicam loaded proniosomal formula proved to be non-irritant, with significantly higher anti-inflammatory and analgesic effects compared to that of the oral market tenoxicam tablets.

  12. Bit Loading Algorithms for Cooperative OFDM Systems

    Directory of Open Access Journals (Sweden)

    Bo Gui

    2007-12-01

    Full Text Available We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.

  13. Bit Loading Algorithms for Cooperative OFDM Systems

    Directory of Open Access Journals (Sweden)

    Gui Bo

    2008-01-01

    Full Text Available Abstract We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.

  14. Hydraulic Soft Yaw System Load Reduction and Prototype Results

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Markussen, Kristian

    2013-01-01

    Introducing a hydraulic soft yaw concept for wind turbines leads to significant load reductions in the wind turbine structure. The soft yaw system operates as a shock absorption system on a car, hence absorbing the loading from turbulent wind conditions instead of leading them into the stiff wind...

  15. Evaluation of a load measurement system for cotton harvesters

    Science.gov (United States)

    The objective of this work is to develop and characterize the performance of a system used onboard a cotton harvester for obtaining seed cotton weight data. This system can be used to measure seed cotton weight on a load by load basis, thereby enhancing the ability for a producer to conduct on-farm ...

  16. Structure analysis and performance measurement of Chinese health delivery system

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: Although evidence has already demonstrated that the performance of Health Delivery System (HDS) varies widely across nations, relatively little is known about the factors that give rise to these variations and the key point to improve the performance besides adjusting system structure. By setup of HDS performance measurement system on the base of association of financial, social, and environmental characteristics, we construct system dynamic model of HDS to simulate the invention policies. Methods:Performance measures were collected from HDS in 31 regions of China and combined with secondary data sources. Multivariate, linear, nonlinear regression and factor analysis models were used to estimate associations between system characteristics and the performance. Results: Performance varied significantly with the size, financial resources and organizational structure of HDS. Performance measurement system of health delivery system was developed to give the rank of all Chinese regions. Conclusion: Performance measurement system of HDS is the basic of HDS modeling by system dynamic.

  17. Delivery systems and cost recovery in Mectizan treatment for onchocerciasis.

    Science.gov (United States)

    Amazigo, U; Noma, M; Boatin, B A; Etya'alé, D E; Sékétéli, A; Dadzie, K Y

    1998-04-01

    The efficiency of on-going delivery systems and cost recovery in Mectizan (ivermectin, MSD) treatment for onchocerciasis are reviewed. The search is on for an effective system of Mectizan delivery, involving drug procurement, delivery from port to districts and distribution to eligible persons, which can be sustained by the endemic countries for many years. The mechanisms for procuring and clearing the drug at the ports, and the drug's integration into the existing delivery systems of each national health service, need to be improved. Although large-scale treatments by mobile teams or community-based methods evidently achieve high and satisfactory rates of coverage, they also incur high recurrent costs which have to be covered by external partners and are not sustainable by national health services. Cost-sharing is considered an important factor in a sustainable delivery system and community-directed treatment, in which the community shares the cost and ownership of local distribution and is empowered to design and implement it, is likely to be more cost-effective and sustainable.

  18. Niosomes: a controlled and novel drug delivery system.

    Science.gov (United States)

    Rajera, Rampal; Nagpal, Kalpana; Singh, Shailendra Kumar; Mishra, Dina Nath

    2011-01-01

    During the past decade formulation of vesicles as a tool to improve drug delivery, has created a lot of interest amongst the scientist working in the area of drug delivery systems. Vesicular system such as liposomes, niosomes, transferosomes, pharmacosomes and ethosomes provide an alternative to improve the drug delivery. Niosomes play an important role owing to their nonionic properties, in such drug delivery system. Design and development of novel drug delivery system (NDDS) has two prerequisites. First, it should deliver the drug in accordance with a predetermined rate and second it should release therapeutically effective amount of drug at the site of action. Conventional dosage forms are unable to meet these requisites. Niosomes are essentially non-ionic surfactant based multilamellar or unilamellar vesicles in which an aqueous solution of solute is entirely enclosed by a membrane resulting from the organization of surfactant macromolecules as bilayer. Niosomes are formed on hydration of non-ionic surfactant film which eventually hydrates imbibing or encapsulating the hydrating aqueous solution. The main aim of development of niosomes is to control the release of drug in a sustained way, modification of distribution profile of drug and for targeting the drug to the specific body site. This paper deals with composition, characterization/evaluation, merits, demerits and applications of niosomes.

  19. An epitope delivery system for use with recombinant mycobacteria

    NARCIS (Netherlands)

    Hetzel, C.; Janssen, R.; Ely, S.J.; Kristensen, N.M.; Bunting, K.; Cooper, J.B.; Lamb, J.R.; Young, D.B.; Thole, J.E.R.

    1998-01-01

    We have developed a novel epitope delivery system based on the insertion of peptides within a permissive loop of a bacterial superoxide dismutase molecule. This system allowed high-level expression of heterologous peptides in two mycobacterial vaccine strains, Mycobacterium bovis bacille Calmette- G

  20. FORMATION OF POROUS MEMBRANES FOR DRUG DELIVERY SYSTEMS

    NARCIS (Netherlands)

    VANDEWITTE, P; ESSELBRUGGE, H; PETERS, AMP; DIJKSTRA, PJ; FEIJEN, J; GROENEWEGEN, RJJ; SMID, J; OLIJSLAGER, J; SCHAKENRAAD, JM; EENINK, MJD; SAM, AP

    1993-01-01

    Highly crystalline porous hollow poly (L-lactide) (PLLA) fibres suitable for the delivery of various drugs were obtained using a dry-wet spinning process. The pore structure of the fibres could be regulated by changing the spinning systems and spinning conditions. Using the spinning system PLLA-diox

  1. An epitope delivery system for use with recombinant mycobacteria

    NARCIS (Netherlands)

    Hetzel, C.; Janssen, R.; Ely, S.J.; Kristensen, N.M.; Bunting, K.; Cooper, J.B.; Lamb, J.R.; Young, D.B.; Thole, J.E.R.

    1998-01-01

    We have developed a novel epitope delivery system based on the insertion of peptides within a permissive loop of a bacterial superoxide dismutase molecule. This system allowed high-level expression of heterologous peptides in two mycobacterial vaccine strains, Mycobacterium bovis bacille Calmette- G

  2. The influence of microwave radiation on transdermal delivery systems.

    Science.gov (United States)

    Moseley, H; Johnston, S; Allen, A

    1990-03-01

    It has been alleged that the exposure of a transdermal delivery system to leakage of microwave radiation from a domestic microwave oven can result in the user receiving a second-degree burn in the area of the patch. Several transdermal delivery systems were exposed to microwave radiation from an Electro Medical Supplies Microtron 200 microwave diathermy unit. Temperature rises of up to 2.2 degrees C were recorded at a maximum power density of 800 W/m2. These temperature rises were considered insignificant compared to that required to produce a burn. The exposure of transdermal delivery systems to a microwave diathermy field or lower level leakage radiation from a microwave oven is unlikely to cause direct thermal injury to the wearer.

  3. Microscale Symmetrical Electroporator Array as a Versatile Molecular Delivery System

    Science.gov (United States)

    Ouyang, Mengxing; Hill, Winfield; Lee, Jung Hyun; Hur, Soojung Claire

    2017-03-01

    Successful developments of new therapeutic strategies often rely on the ability to deliver exogenous molecules into cytosol. We have developed a versatile on-chip vortex-assisted electroporation system, engineered to conduct sequential intracellular delivery of multiple molecules into various cell types at low voltage in a dosage-controlled manner. Micro-patterned planar electrodes permit substantial reduction in operational voltages and seamless integration with an existing microfluidic technology. Equipped with real-time process visualization functionality, the system enables on-chip optimization of electroporation parameters for cells with varying properties. Moreover, the system’s dosage control and multi-molecular delivery capabilities facilitate intracellular delivery of various molecules as a single agent or in combination and its utility in biological research has been demonstrated by conducting RNA interference assays. We envision the system to be a powerful tool, aiding a wide range of applications, requiring single-cell level co-administrations of multiple molecules with controlled dosages.

  4. Information Delivery System through Bluetooth in Ubiquitous Networks

    Directory of Open Access Journals (Sweden)

    D.Asha Devi

    2009-07-01

    Full Text Available Ubiquitous and pervasive computing (UPC is a popular paradigm whose purpose is to emerge computers into the real world, to serve humans where the ubiquitous network is the underneath infrastructure. In order to provide ubiquitous services (u-Service which deliver useful information to service users without human intervention, this paper implements a proactive information delivery system using Bluetooth technology. Bluetooth is a lowpowered networking service that supports several protocol profiles, most importantly file transfer.Combined together, ubiquitous computing and Bluetooth have the potential to furnish ubiquitous solutions (u-Solutions that are efficient, employ simplified design characteristics, and collaboratively perform functions they are otherwise not capable. Thus, this paper first addresses the current Bluetooth technology. Then, it suggests and develops the proactive information delivery system utilizing Bluetooth and ubiquitous computing network concepts. The proactive information delivery system can be used in many ubiquitous applications such as ubiquitous commerce (u-Commerce and ubiquitous education (u- Education.

  5. Preparation of drug delivery systems using supercritical fluid technology.

    Science.gov (United States)

    Kompella, U B; Koushik, K

    2001-01-01

    Small changes in temperature and pressure near the critical region induce dramatic changes in the density and solubility of supercritical fluids, thereby facilitating the use of environmentally benign agents such as CO2 for their solvent and antisolvent properties in processing a wide variety of materials. While supercritical fluid technologies have been in commercial use in the food and chromatography industries for several years, only recently has this technology made inroads in the formulation of drug delivery systems. This review summarizes some of the recent applications of supercritical fluid technology in the preparation of drug delivery systems. Drugs containing polymeric particles, plain drug particles, solute-containing liposomes, and inclusion complexes of drug and carrier have been formulated using this technology. Also, polymer separation using this technology is enabling the selection of a pure fraction of a polymer, thereby allowing a more precise control of drug release from polymeric delivery systems.

  6. Pulsatile Drug Delivery System Based on Electrohydrodynamic Method

    CERN Document Server

    Zheng, Yi; Hu, Junqiang; Gao, Wenle

    2012-01-01

    Electrohydrodynamic (EHD) generation, a commonly used method in BioMEMS, plays a significant role in the pulsatile drug delivery system for a decade. In this paper, an EHD based drug delivery system is well designed, which can be used to generate a single drug droplet as small as 2.83 nL in 8.5 ms with a total device of 2\\times2\\times3 mm^3, and an external supplied voltage of 1500 V. Theoretically, we derive the expressions for the size and the formation time of a droplet generated by EHD method, while taking into account the drug supply rate, properties of liquid, gap between two electrodes, nozzle size, and charged droplet neutralization. This work proves a repeatable, stable and controllable droplet generation and delivery system based on EHD method experimentally as well as theoretically.

  7. Information Delivery System through Bluetooth in Ubiquitous Networks

    CERN Document Server

    Devi, D Asha; Pavani, V L; Geethanjali, N

    2010-01-01

    computers into the real world, to serve humans where the ubiquitous network is the underneath infrastructure. In order to provide ubiquitous services (u-Service) which deliver useful information to service users without human intervention, this paper implements a proactive information delivery system using Bluetooth technology. Bluetooth is a lowpowered networking service that supports several protocol profiles, most importantly file transfer.Combined together, ubiquitous computing and Bluetooth ha e the potential to furnish ubiquitous solutions (u-Solutions) that are efficient, employ simplified design characteristics, and collaboratively perform functions they are otherwise not capable. Thus, this paper first addresses the current Bluetooth technology. Then, it suggests and develops the proactive information delivery system utilizing Bluetooth and ubiquitous computing network concepts. The proactive information delivery system can be used in many ubiquitous applications such as ubiquitous commerce (u-Commer...

  8. Atorvastatin-loaded nanostructured lipid carriers (NLCs): strategy to overcome oral delivery drawbacks.

    Science.gov (United States)

    Elmowafy, Mohammed; Ibrahim, Hany M; Ahmed, Mohammed A; Shalaby, Khaled; Salama, Ayman; Hefesha, Hossam

    2017-11-01

    Atorvastatin (AT) is a widely used lipid-regulating drug to reduce cholesterol and triglycerides. Its poor aqueous solubility and hepatic metabolism require development of drug delivery systems able to improve its solubility and bypass hepatic effect. For this purpose, atorvastatin nanostructured lipid carriers (AT-NLCs) were prepared and characterized. AT-NLCs were prepared by emulsification using high-speed homogenization followed by ultrasonication. The prepared NLCs showed particle size between 162.5 ± 12 and 865.55 ± 28 nm while zeta potential values varied between -34 ± 0.29 and -23 ± 0.36 mV. They also showed high encapsulation efficiency (>87%) and amorphous state of the drug in lipid matrix. Pharmacokinetic parameters of optimized formulation (NLC-1; composed of 2% Gelucire(®) 43/01, 8% Capryol(®) PGMC, 2% Pluronic(®)F68 and 0.5% lecithin) revealed 3.6- and 2.1-fold increase in bioavailability as compared to atorvastatin suspension and commercial product (Lipitor(®)), respectively. Administration of NLC-1 led to significant reduction (p oral bioavailability and in vivo performance of AT.

  9. Gene delivery nanocarriers of bioactive glass with unique potential to load BMP2 plasmid DNA and to internalize into mesenchymal stem cells for osteogenesis and bone regeneration

    Science.gov (United States)

    Kim, Tae-Hyun; Singh, Rajendra K.; Kang, Min Sil; Kim, Joong-Hyun; Kim, Hae-Won

    2016-04-01

    The recent development of bioactive glasses with nanoscale morphologies has spurred their specific applications in bone regeneration, for example as drug and gene delivery carriers. Bone engineering with stem cells genetically modified with this unique class of nanocarriers thus holds great promise in this avenue. Here we report the potential of the bioactive glass nanoparticle (BGN) system for the gene delivery of mesenchymal stem cells (MSCs) targeting bone. The composition of 15% Ca-added silica, proven to be bone-bioactive, was formulated into surface aminated mesoporous nanospheres with enlarged pore sizes, to effectively load and deliver bone morphogenetic protein-2 (BMP2) plasmid DNA. The enlarged mesopores were highly effective in loading BMP2-pDNA with an efficiency as high as 3.5 wt% (pDNA w.r.t. BGN), a level more than twice than for small-sized mesopores. The BGN nanocarriers released the genetic molecules in a highly sustained manner (for as long as 2 weeks). The BMP2-pDNA/BGN complexes were effectively internalized to rat MSCs with a cell uptake level of ~73%, and the majority of cells were transfected to express the BMP2 protein. Subsequent osteogenesis of the transfected MSCs was demonstrated by the expression of bone-related genes, including bone sialoprotein, osteopontin, and osteocalcin. The MSCs transfected with BMP2-pDNA/BGN were locally delivered inside a collagen gel to the target calvarium defects. The results showed significantly improved bone regeneration, as evidenced by the micro-computed tomographic, histomorphometric and immunohistochemical analyses. This study supports the excellent capacity of the BGN system as a pDNA-delivery nanocarrier in MSCs, and the engineered system, BMP2-pDNA/BGN with MSCs, may be considered a new promising candidate to advance the therapeutic potential of stem cells through genetic modification, targeting bone defects and diseases.The recent development of bioactive glasses with nanoscale morphologies has

  10. Efficiency performance of China's health care delivery system.

    Science.gov (United States)

    Zhang, Luyu; Cheng, Gang; Song, Suhang; Yuan, Beibei; Zhu, Weiming; He, Li; Ma, Xiaochen; Meng, Qingyue

    2017-07-01

    Improving efficiency performance of the health care delivery system has been on the agenda for the health system reform that China initiated in 2009. This study examines the changes in efficiency performance and determinants of efficiency after the reform to provide evidence to assess the progress of the reform from the perspective of efficiency. Descriptive analysis, Data Envelopment Analysis, the Malmquist Index, and multilevel regressions are used with data from multiple sources, including the World Bank, the China Health Statistical Yearbook, and routine reports. The results indicate that over the last decade, health outcomes compared with health investment were relatively higher in China than in most other countries worldwide, and the trend was stable. The overall efficiency and total factor productivity increased after the reform, indicating that the reform was likely to have had a positive impact on the efficiency performance of the health care delivery system. However, the health care delivery structure showed low system efficiency, mainly attributed to the weakened primary health care system. Strengthening the primary health care system is central to enhancing the future performance of China's health care delivery system. Copyright © 2017 John Wiley & Sons, Ltd.

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

    Directory of Open Access Journals (Sweden)

    Priya Bawa

    2011-12-01

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

  12. Preparation, characterization, and in vitro targeted delivery of folate-decorated paclitaxel-loaded bovine serum albumin nanoparticles

    Directory of Open Access Journals (Sweden)

    Dongmei Zhao

    2010-09-01

    Full Text Available Dongmei Zhao, Xiuhua Zhao, Yuangang Zu, Jialei Li, Yu Zhang, Ru Jiang, Zhonghua ZhangKey Laboratory of Forest Plant Ecology, Northeast Forestry University, Ministry of Education, Harbin, Heilongjiang, ChinaAbstract: Paclitaxel (Taxol® is an important anticancer drug in clinical use for treatment of a variety of cancers. Because of its low solubility, it is formulated in high concentration in Cremophor EL® which induces hypersensitivity reactions. In this study, targeted delivery of paclitaxel-loaded nanoparticles was prepared by a desolvation procedure, crosslinked on the wall material of bovine serum albumin, and subsequently decorated by folic acid. The characteristics of the nanoparticles, such as amount of folate conjugation, surface morphology, drug entrapment efficiency, drug loading efficiency, and release kinetics were investigated in vitro. The targeting effect was investigated in vitro by cancer cell uptake of fluorescein isothiocyanate-labeled nanoparticles. The spherical nanoparticles obtained were negatively charged with a zeta potential of about -30 mV, and characterized around 210 nm with a narrow size distribution. Drug entrapment efficiency and drug loading efficiency were approximately 95.3% and 27.2%, respectively. The amount of folate conjugation was 9.22 µg/mg of bovine serum albumin. The folate-decorated nanoparticles targeted a human prostate cancer cell line effectively.Keywords: paclitaxel, bovine serum albumin, folate, nanoparticles, target delivery

  13. A novel control strategy for load converter of DC isolated distribution system under unbalanced loading conditions

    Institute of Scientific and Technical Information of China (English)

    R. NOROOZIAN; M. ABEDI; G.B. GHAREHPETIAN; S. H. HOSSEINI

    2009-01-01

    A novel control strategy for the load converter supplying the unbalanced AC load in a DC isolated distribution system is presented. The control algorithm results in balanced and sinusoidal load voltages under unbalanced AC loading. The unbalanced load is characterized in the d-q-0 rotating coordinate based on symmetrical sequence components. Also, the mathematical model of the load converter in both a-b-c and d-q-0 coordinates is derived by using the average large signal model. Then, two control strategies for the load converter are presented. The first one uses the conventional d-q-0 controller to ensure the voltage and current regulation. The second one is a newly proposed control strategy based on the decomposition of the voltage and current into instantaneous positive, negative, and zero sequences. These three sequences are controlled independently in their own reference frames as DC signals. The performance of the load converter using these two control strategies is compared. Simulation results show the validity and capability of the newly proposed control strategy.

  14. [Development of drug delivery systems for targeting to macrophages].

    Science.gov (United States)

    Chono, Sumio

    2007-09-01

    Drug delivery systems (DDS) using liposomes as drug carriers for targeting to macrophages have been developed for the treatment of diseases that macrophages are related to their progress. Initially, DDS for the treatment of atherosclerosis are described. The influence of particle size on the drug delivery to atherosclerotic lesions that macrophages are richly present and antiatherosclerotic effects following intravenous administration of liposomes containing dexamethasone (DXM-liposomes) was investigated in atherogenic mice. Both the drug delivery efficacy of DXM-liposomes (particle size, 200 nm) to atherosclerotic lesions and their antiatherosclerotic effects were greater than those of 70 and 500 nm. These results indicate that there is an optimal particle size for drug delivery to atherosclerotic lesions. DDS for the treatment of respiratory infections are then described. The influence of particle size and surface mannosylation on the drug delivery to alveolar macrophages (AMs) and antibacterial effects following pulmonary administration of liposomes containing ciprofloxacin (CPFX-liposomes) was investigated in rats. The drug delivery efficacy of CPFX-liposomes to AMs was particle size-dependent over the range 100-1000 nm and then became constant at over 1000 nm. These results indicate that the most effective size is 1000 nm. Both the drug delivery efficacy of mannosylated CPFX-liposomes (particle size, 1000 nm) to AMs and their antibacterial effects were significantly greater than those of unmodified CPFX-liposomes. These results indicate that the surface mannosylation is useful method for drug delivery to AMs. This review provides useful information to help in the development of novel pharmaceutical formulations aimed at drug targeting to macrophages.

  15. Ultrafast fiber beam delivery: system technology and industrial application

    Science.gov (United States)

    Funck, Max C.; Eilzer, Sebastian; Wedel, Björn

    2017-02-01

    Flexible beam delivery of high power pico- and femtosecond pulses offers great advantages in industrial applications. Complex free space beam delivery as found in robot or gantry systems can be replaced, laser safety and uptime increased and system integration in production environment simplified. Only recently fiber beam delivery has become available for ultrafast lasers while it has been an established standard for cw and pulsed laser sources for many years. Using special kinds of fiber that guide the laser beam mostly inside a hollow core, nonlinear effects and catastrophic damage that would arise in conventional glass fibers can be avoided. Today, ultrafast pulses with several 100 μJ and hundreds of MW can be transmitted in quasi single mode fashion with micro-structured hollow core fibers. During the last years we have developed a modular beam delivery system that suits industrial ultrafast lasers and can be integrated into existing processing machines. Micro-structured hollow core fibers inside the sealed laser light cable efficiently guide high-power laser pulses over distances of several meters with excellent beam quality, while power, pulse duration and polarization are maintained. We report on the technology required for fiber beam delivery of ultrafast laser pulses and discuss requirements for successful integration into industrial production as well as achievable performance under realistic operation and show examples of micromachining applications.

  16. Process development work plan for waste feed delivery system

    Energy Technology Data Exchange (ETDEWEB)

    Papp, I.G.

    1998-04-02

    This work plan defines the process used to develop project definition for Waste Feed Delivery (WFD). Project definition provides the direction for development of definitive design media required for the ultimate implementation of operational processing hardware and software. Outlines for the major deliverables are attached as appendices. The implementation of hardware and software will accommodate requirements for safe retrieval and delivery of waste currently stored in Hanford`s underground storage tanks. Operations and maintenance ensure the availability of systems, structures, and components for current and future planned operations within the boundary of the Tank Waste Remediation System (TWRS) authorization basis.

  17. Short-term load forecasting of power system

    Science.gov (United States)

    Xu, Xiaobin

    2017-05-01

    In order to ensure the scientific nature of optimization about power system, it is necessary to improve the load forecasting accuracy. Power system load forecasting is based on accurate statistical data and survey data, starting from the history and current situation of electricity consumption, with a scientific method to predict the future development trend of power load and change the law of science. Short-term load forecasting is the basis of power system operation and analysis, which is of great significance to unit combination, economic dispatch and safety check. Therefore, the load forecasting of the power system is explained in detail in this paper. First, we use the data from 2012 to 2014 to establish the partial least squares model to regression analysis the relationship between daily maximum load, daily minimum load, daily average load and each meteorological factor, and select the highest peak by observing the regression coefficient histogram Day maximum temperature, daily minimum temperature and daily average temperature as the meteorological factors to improve the accuracy of load forecasting indicators. Secondly, in the case of uncertain climate impact, we use the time series model to predict the load data for 2015, respectively, the 2009-2014 load data were sorted out, through the previous six years of the data to forecast the data for this time in 2015. The criterion for the accuracy of the prediction is the average of the standard deviations for the prediction results and average load for the previous six years. Finally, considering the climate effect, we use the BP neural network model to predict the data in 2015, and optimize the forecast results on the basis of the time series model.

  18. Electrosprayed nanoparticle delivery system for controlled release

    Energy Technology Data Exchange (ETDEWEB)

    Eltayeb, Megdi, E-mail: megdi.eltayeb@sustech.edu [Department of Biomedical Engineering, Sudan University of Science and Technology, PO Box 407, Khartoum (Sudan); Stride, Eleanor, E-mail: eleanor.stride@eng.ox.ac.uk [Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Old Road Campus Research Building, Headington OX3 7DQ (United Kingdom); Edirisinghe, Mohan, E-mail: m.edirisinghe@ucl.ac.uk [Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Harker, Anthony, E-mail: a.harker@ucl.ac.uk [London Centre for Nanotechnology, Gordon Street, London WC1H 0AH (United Kingdom); Department of Physics & Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)

    2016-09-01

    This study utilises an electrohydrodynamic technique to prepare core-shell lipid nanoparticles with a tunable size and high active ingredient loading capacity, encapsulation efficiency and controlled release. Using stearic acid and ethylvanillin as model shell and active ingredients respectively, we identify the processing conditions and ratios of lipid:ethylvanillin required to form nanoparticles. Nanoparticles with a mean size ranging from 60 to 70 nm at the rate of 1.37 × 10{sup 9} nanoparticles per minute were prepared with different lipid:ethylvanillin ratios. The polydispersity index was ≈ 21% and the encapsulation efficiency ≈ 70%. It was found that the rate of ethylvanillin release was a function of the nanoparticle size, and lipid:ethylvanillin ratio. The internal structure of the lipid nanoparticles was studied by transmission electron microscopy which confirmed that the ethylvanillin was encapsulated within a stearic acid shell. Fourier transform infrared spectroscopy analysis indicated that the ethylvanillin had not been affected. Extensive analysis of the release of ethylvanillin was performed using several existing models and a new diffusive release model incorporating a tanh function. The results were consistent with a core-shell structure. - Highlights: • Electrohydrodynamic spraying is used to produce lipid-coated nanoparticles. • A new model is proposed for the release rates of active components from nanoparticles. • The technique has potential applications in food science and medicine. • Electrohydrodynamic processing controlled release lipid nanoparticles.

  19. A real-time virtual delivery system for photon radiotherapy delivery monitoring

    Directory of Open Access Journals (Sweden)

    Feng Shi

    2014-03-01

    Full Text Available Purpose: Treatment delivery monitoring is important for radiotherapy, which enables catching dosimetric error at the earliest possible opportunity. This project develops a virtual delivery system to monitor the dose delivery process of photon radiotherapy in real-time using GPU-based Monte Carlo (MC method.Methods: The simulation process consists of 3 parallel CPU threads. A thread T1 is responsible for communication with a linac, which acquires a set of linac status parameters, e.g. gantry angles, MLC configurations, and beam MUs every 20 ms. Since linac vendors currently do not offer interface to acquire data in real time, we mimic this process by fetching information from a linac dynalog file at the set frequency. Instantaneous beam fluence map (FM is calculated based. A FM buffer is also created in T1 and the instantaneous FM is accumulated to it. This process continues, until a ready signal is received from thread T2 on which an in-house developed MC dose engine executes on GPU. At that moment, the accumulated FM is transferred to T2 for dose calculations, and the FM buffer in T1 is cleared. Once the dose calculation finishes, the resulting 3D dose distribution is directed to thread T3, which displays it in three orthogonal planes in color wash overlaid on the CT image. This process continues to monitor the 3D dose distribution in real-time.Results: An IMRT and a VMAT cases used in our patient-specific QA are studied. Maximum dose differences between our system and treatment planning system are 0.98% and 1.58% for the IMRT and VMAT cases, respectively. The update frequency is >10Hz and the relative uncertainty level is 2%.Conclusion: By embedding a GPU-based MC code in a novel data/work flow, it is possible to achieve real-time MC dose calculations to monitor delivery process.------------------------------Cite this article as: Shi F, Gu X, Graves YJ, Jiang S, Jia X. A real-time virtual delivery system for photon radiotherapy delivery

  20. Hydraulic Soft Yaw System Load Reduction and Prototype Results

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Markussen, Kristian

    2013-01-01

    Introducing a hydraulic soft yaw concept for wind turbines leads to significant load reductions in the wind turbine structure. The soft yaw system operates as a shock absorption system on a car, hence absorbing the loading from turbulent wind conditions instead of leading them into the stiff wind...... operates. Further it is analyzed how the soft yaw system influence the power production of the turbine. It is shown that the influence is minimal, but at larger yaw errors the effect is possitive. Due to the implemeted functions in the hydraulic soft yaw system such as even load distribution on the pinions...

  1. OPERATIONAL ACCURACY IMPROVEMENT OF DIGITAL SERVO SYSTEM CONTAINING UNBALANCED LOAD

    Directory of Open Access Journals (Sweden)

    A. Stryzhniou

    2013-01-01

    Full Text Available The paper considers a structural flowchart of a typical digital servo system and its operational principle. A method for determination of the unbalanced load effect on the accuracy of the system operation is described in the paper. The paper proposes a method for compensation of the  unbalanced load influence on the system operation. The experimental verification of the unbalanced load effect on the operational accuracy of the servo system and compensation of these influences have been executed in the paper.

  2. Drug-in-cyclodextrin-in-liposomes: A novel drug delivery system for flurbiprofen.

    Science.gov (United States)

    Zhang, Lina; Zhang, Qi; Wang, Xin; Zhang, Wenji; Lin, Congcong; Chen, Fen; Yang, Xinggang; Pan, Weisan

    2015-08-15

    A novel delivery system based on drug-cyclodextrin (CD) complexation and liposomes has been developed to improve therapeutic effect. Three different means, i.e., co-evaporation (COE), co-ground (GR) and co-lyophilization (COL) and three different CDs (β-CD, HP-β-CD and SBE-β-CD) were contrasted to investigate the characteristics of the end products. FP/FP-CD loaded liposomes were obtained by thin layer evaporation technique. Size, zeta potential and encapsulation efficiency were investigated by light scattering analysis and minicolumn centrifugation. Differential scanning calorimetry (DSC) and transmission electron microscopy (TEM) showed the amorphous form of complexes and spherical morphology of FP-HP-β-CD COE loaded liposomes. The pH 7.4 phosphate buffer solution (PBS) was selected as the medium for the in vitro release. Wistar rats were put into use to study the pharmacokinetic behavior in vivo. FP-HP-β-CD COE loaded liposomes showed the better physicochemical characters that followed the average particle size, polydispersity index, zeta potential and mean encapsulation efficiency 158±10 nm, 0.19±0.1, -12.4±0.1 mW and 56.1±0.5%, separately. The relative bioavailability of FP-HP-β-CD COE loaded liposomes was 420%, 201% and 402% compared with FP solution, FP-HP-β-CD and FP-liposomes, respectively. In conclusion, the novel delivery system improved the relative bioavailability of FP significantly and provided a perspective way for delivery of insoluble drugs.

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

    Science.gov (United States)

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

    2015-11-01

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

  4. Anthracycline Drugs on Modified Surface of Quercetin-Loaded Polymer Nanoparticles: A Dual Drug Delivery Model for Cancer Treatment.

    Directory of Open Access Journals (Sweden)

    Chabita Saha

    Full Text Available Polymer nanoparticles are vehicles used for delivery of hydrophobic anti-cancer drugs, like doxorubicin, paclitaxel or chemopreventors like quercetin (Q. The present study deals with the synthesis and characterisation of nano formulations (NFs from Q loaded PLGA (poly lactic-co-glycolic acid nano particles (NPs by surface modification. The surface of Q-loaded (NPs is modified by coating with biopolymers like bovine serum albumin (BSA or histones (His. Conventional chemotherapeutic drugs adriamycin (ADR and mitoxantrone (MTX are bound to BSA and His respectively before being coated on Q-loaded NPs to nano formulate NF1 and NF2 respectively. The sizes of these NFs are in the range 400-500 nm as ascertained by SEM and DLS measurements. Encapsulation of Q in polymer NPs is confirmed from shifts in FT-IR, TGA and DSC traces of Q-loaded NPs compared to native PLGA and Q. Surface modification in NFs is evidenced by three distinct regions in their TEM images; the core, polymer capsule and the coated surface. Negative zeta potential of Q-loaded NPs shifted to positive potential on surface modification in NF1 and NF2. In vitro release of Q from the NFs lasted up to twenty days with an early burst release. NF2 is better formulation than NF1 as loading of MTX is 85% compared to 23% loading of ADR. Such NFs are expected to overcome multi-drug resistance (MDR by reaching and treating the target cancerous cells by virtue of size, charge and retention.

  5. Potential for Layered Double Hydroxides-Based, Innovative Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Kai Zhang

    2014-04-01

    Full Text Available Layered Double Hydroxides (LDHs-based drug delivery systems have, for many years, shown great promises for the delivery of chemical therapeutics and bioactive molecules to mammalian cells in vitro and in vivo. This system offers high efficiency and drug loading density, as well as excellent protection of loaded molecules from undesired degradation. Toxicological studies have also found LDHs to be biocompatible compared with other widely used nanoparticles, such as iron oxide, silica, and single-walled carbon nanotubes. A plethora of bio-molecules have been reported to either attach to the surface of or intercalate into LDH materials through co-precipitation or anion-exchange reaction, including amino acid and peptides, ATPs, vitamins, and even polysaccharides. Recently, LDHs have been used for gene delivery of small molecular nucleic acids, such as antisense, oligonucleotides, PCR fragments, siRNA molecules or sheared genomic DNA. These nano-medicines have been applied to target cells or organs in gene therapeutic approaches. This review summarizes current progress of the development of LDHs nanoparticle drug carriers for nucleotides, anti-inflammatory, anti-cancer drugs and recent LDH application in medical research. Ground breaking studies will be highlighted and an outlook of the possible future progress proposed. It is hoped that the layered inorganic material will open up new frontier of research, leading to new nano-drugs in clinical applications.

  6. Potential for layered double hydroxides-based, innovative drug delivery systems.

    Science.gov (United States)

    Zhang, Kai; Xu, Zhi Ping; Lu, Ji; Tang, Zhi Yong; Zhao, Hui Jun; Good, David A; Wei, Ming Qian

    2014-01-01

    Layered Double Hydroxides (LDHs)-based drug delivery systems have, for many years, shown great promises for the delivery of chemical therapeutics and bioactive molecules to mammalian cells in vitro and in vivo. This system offers high efficiency and drug loading density, as well as excellent protection of loaded molecules from undesired degradation. Toxicological studies have also found LDHs to be biocompatible compared with other widely used nanoparticles, such as iron oxide, silica, and single-walled carbon nanotubes. A plethora of bio-molecules have been reported to either attach to the surface of or intercalate into LDH materials through co-precipitation or anion-exchange reaction, including amino acid and peptides, ATPs, vitamins, and even polysaccharides. Recently, LDHs have been used for gene delivery of small molecular nucleic acids, such as antisense, oligonucleotides, PCR fragments, siRNA molecules or sheared genomic DNA. These nano-medicines have been applied to target cells or organs in gene therapeutic approaches. This review summarizes current progress of the development of LDHs nanoparticle drug carriers for nucleotides, anti-inflammatory, anti-cancer drugs and recent LDH application in medical research. Ground breaking studies will be highlighted and an outlook of the possible future progress proposed. It is hoped that the layered inorganic material will open up new frontier of research, leading to new nano-drugs in clinical applications.

  7. Lipoprotein-Related and Apolipoprotein-Mediated Delivery Systems for Drug Targeting and Imaging

    Science.gov (United States)

    Almer, Gunter; Mangge, Harald; Zimmer, Andreas; Prassl, Ruth

    2015-01-01

    The integration of lipoprotein-related or apolipoprotein-targeted nanoparticles as pharmaceutical carriers opens new therapeutic and diagnostic avenues in nanomedicine. The concept is to exploit the intrinsic characteristics of lipoprotein particles as being the natural transporter of apolar lipids and fat in human circulation. Discrete lipoprotein assemblies and lipoprotein-based biomimetics offer a versatile nanoparticle platform that can be manipulated and tuned for specific medical applications. This article reviews the possibilities for constructing drug loaded, reconstituted or artificial lipoprotein particles. The advantages and limitations of lipoprotein-based delivery systems are critically evaluated and potential future challenges, especially concerning targeting specificity, concepts for lipoprotein rerouting and design of innovative lipoprotein mimetic particles using apolipoprotein sequences as targeting moieties are discussed. Finally, the review highlights potential medical applications for lipoprotein-based nanoparticle systems in the fields of cardiovascular research, cancer therapy, gene delivery and brain targeting focusing on representative examples from literature. PMID:26180001

  8. A COMPREHENSIVE REVIEW OF PULSATILE DRUG DELIVERY SYSTEMS

    Directory of Open Access Journals (Sweden)

    Rompicharla Bhargavi

    2012-03-01

    Full Text Available Pulsatile drug delivery systems are gaining popularity in the field of pharmaceutical formulation, research and development. The prime advantage in this drug delivery is that the drug is released as per the pathophysiological need of the disease. As a result the change of development of drug resistance which is seen in conventional and sustained released formulations can be reduced. This therapy is mainly applicable where sustained action is not required and the drugs are toxic. Basic point of development of this formulation is to find out the circadian rhythms that is a suitable indicator that will trigger the release of drug from the device. Clock genes are the genes that control the circadian rhythms in human physiology. Pulsatile drug delivery systems are promising incase of asthma, cardiovascular diseases, peptic ulcers, arthritis, and hypercholesterolemic conditions.

  9. Novel engineered systems for oral, mucosal and transdermal drug delivery.

    Science.gov (United States)

    Li, Hairui; Yu, Yuan; Faraji Dana, Sara; Li, Bo; Lee, Chi-Ying; Kang, Lifeng

    2013-08-01

    Technological advances in drug discovery have resulted in increasing number of molecules including proteins and peptides as drug candidates. However, how to deliver drugs with satisfactory therapeutic effect, minimal side effects and increased patient compliance is a question posted before researchers, especially for those drugs with poor solubility, large molecular weight or instability. Microfabrication technology, polymer science and bioconjugate chemistry combine to address these problems and generate a number of novel engineered drug delivery systems. Injection routes usually have poor patient compliance due to their invasive nature and potential safety concerns over needle reuse. The alternative non-invasive routes, such as oral, mucosal (pulmonary, nasal, ocular, buccal, rectal, vaginal), and transdermal drug delivery have thus attracted many attentions. Here, we review the applications of the novel engineered systems for oral, mucosal and transdermal drug delivery.

  10. Smart surface-enhanced Raman scattering traceable drug delivery systems.

    Science.gov (United States)

    Liu, Lei; Tang, Yonghong; Dai, Sheng; Kleitz, Freddy; Qiao, Shi Zhang

    2016-07-07

    A novel smart nanoparticle-based system has been developed for tracking intracellular drug delivery through surface-enhanced Raman scattering (SERS). This new drug delivery system (DDS) shows targeted cytotoxicity towards cancer cells via pH-cleavable covalent carboxylic hydrazone links and the SERS tracing capability based on gold@silica nanocarriers. Doxorubicin, as a model anticancer drug, was employed to compare SERS with conventional fluorescence tracing approaches. It is evident that SERS demonstrates higher sensitivity and resolution, revealing intracellular details, as the strengths of the original Raman signals can be amplified by SERS. Importantly, non-destructive SERS will provide the designed DDS with great autonomy and potential to study the dynamic procedures of non-fluorescent drug delivery into living cells.

  11. Advanced Drug Delivery Systems - a Synthetic and Biological Applied Evaluation

    DEFF Research Database (Denmark)

    Bjerg, Lise Nørkjær

    Specific delivery of drugs to diseased sites in the body is a major topic in the development of drug delivery system today. Especially, the field of cancer treatment needs improved drug delivery systems as the strong dose-limiting side effects of chemotherapy today often present a barrier...... unloading of the encapsulated drug have been tried optimized in a variety of ways. Many propose the use of small molecules, such as vitamins and peptides, for active targeting of the liposomes to overexpressed receptors on the cancerous tissue. Once located close to the diseased site a trigger mechanism...... for releasing the drug from the liposome interior is often needed. Several approaches have been suggested to work as release mechanisms such a pH changes, the presence of enzymes or external applied stimulus as heat or light. Chapter two deals with the synthesis of the functionalized phospholipids, which...

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

    Science.gov (United States)

    Maity, Amit Ranjan; Stepensky, David

    2016-01-01

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

  13. Mitomycin C-soybean phosphatidylcholine complex-loaded self-assembled PEG-lipid-PLA hybrid nanoparticles for targeted drug delivery and dual-controlled drug release.

    Science.gov (United States)

    Li, Yang; Wu, Hongjie; Yang, Xiangrui; Jia, Mengmeng; Li, Yanxiu; Huang, Yu; Lin, Jinyan; Wu, Shichao; Hou, Zhenqing

    2014-08-04

    Most present drug-phospholipid delivery systems were based on a water-insoluble drug-phospholipid complex but rarely water-soluble drug-phospholipid complex. Mitomycin C (MMC) is a water-soluble anticancer drug extensively used in first-line chemotherapy but is limited by its poor aqueous stability in vitro, rapid elimination from the body, and lack of target specificity. In this article, we report the MMC-soybean phosphatidylcholine complex-loaded PEG-lipid-PLA hybrid nanoparticles (NPs) with Folate (FA) functionalization (FA-PEG-PE-PLA NPs@MMC-SPC) for targeted drug delivery and dual-controlled drug release. FA-PEG-PE-PLA NPs@MMC-SPC comprise a hydrophobic core (PLA) loaded with MMC-SPC, an amphiphilic lipid interface layer (PE), a hydrophilic shell (PEG), and a targeting ligand (FA) on the surface, with a spherical shape, a nanoscaled particle size, and high drug encapsulation efficiency of almost 95%. The advantage of the new drug delivery systems is the early phase controlled drug release by the drug-phospholipid complex and the late-phase controlled drug release by the pH-sensitive polymer-lipid hybrid NPs. In vitro cytotoxicity and hemolysis assays demonstrated that the drug carriers were cytocompatible and hemocompatible. The pharmacokinetics study in rats showed that FA-PEG-PE-PLA NPs@MMC-SPC significantly prolonged the blood circulation time compared to that of the free MMC. More importantly, FA-PEG-PE-PLA NPs@MMC-SPC presented the enhanced cell uptake/cytotoxicity in vitro and superior tumor accumulation/therapeutic efficacy in vivo while reducing the systemic toxicity. A significant accumulation of MMC in the nuclei as the site of MMC action achieved in FA-PEG-PE-PLA NPs@MMC-SPC made them ideal for MMC drug delivery. This study may provide an effective strategy for the design and development of the water-soluble drug-phospholipid complex-based targeted drug delivery and sustained/controlled drug release.

  14. Smart surface-enhanced Raman scattering traceable drug delivery systems

    Science.gov (United States)

    Liu, Lei; Tang, Yonghong; Dai, Sheng; Kleitz, Freddy; Qiao, Shi Zhang

    2016-06-01

    A novel smart nanoparticle-based system has been developed for tracking intracellular drug delivery through surface-enhanced Raman scattering (SERS). This new drug delivery system (DDS) shows targeted cytotoxicity towards cancer cells via pH-cleavable covalent carboxylic hydrazone links and the SERS tracing capability based on gold@silica nanocarriers. Doxorubicin, as a model anticancer drug, was employed to compare SERS with conventional fluorescence tracing approaches. It is evident that SERS demonstrates higher sensitivity and resolution, revealing intracellular details, as the strengths of the original Raman signals can be amplified by SERS. Importantly, non-destructive SERS will provide the designed DDS with great autonomy and potential to study the dynamic procedures of non-fluorescent drug delivery into living cells.A novel smart nanoparticle-based system has been developed for tracking intracellular drug delivery through surface-enhanced Raman scattering (SERS). This new drug delivery system (DDS) shows targeted cytotoxicity towards cancer cells via pH-cleavable covalent carboxylic hydrazone links and the SERS tracing capability based on gold@silica nanocarriers. Doxorubicin, as a model anticancer drug, was employed to compare SERS with conventional fluorescence tracing approaches. It is evident that SERS demonstrates higher sensitivity and resolution, revealing intracellular details, as the strengths of the original Raman signals can be amplified by SERS. Importantly, non-destructive SERS will provide the designed DDS with great autonomy and potential to study the dynamic procedures of non-fluorescent drug delivery into living cells. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr03869g

  15. Mercury sorbent delivery system for flue gas

    Science.gov (United States)

    Klunder; ,Edgar B.

    2009-02-24

    The invention presents a device for the removal of elemental mercury from flue gas streams utilizing a layer of activated carbon particles contained within the filter fabric of a filter bag for use in a flue gas scrubbing system.

  16. Doxorubicin-loaded aromatic imine-contained amphiphilic branched star polymer micelles: synthesis, self-assembly, and drug delivery

    Directory of Open Access Journals (Sweden)

    Qiu L

    2015-05-01

    Full Text Available Liang Qiu, Chun-Yan Hong, Cai-Yuan Pan Chinese Academy of Sciences Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, People’s Republic of China Abstract: Redox- and pH-sensitive branched star polymers (BSPs, BP(DMAEMA-co-MAEBA-co-DTDMA(PMAIGPns, have been successively prepared by two steps of reversible addition–fragmentation chain transfer (RAFT polymerization. The first step is RAFT polymerization of 2-(N,N-dimethylaminoethylmethacrylate (DMAEMA and p-(methacryloxyethoxybenzaldehyde (MAEBA in the presence of divinyl monomer, 2,2'-dithiodiethoxyl dimethacrylate (DTDMA. The resultant branched polymers were used as a macro-RAFT agent in the subsequent RAFT polymerization. After hydrolysis of the BSPs to form BP(DMAEMA-co-MAEBA-co-DTDMA(PMAGPns (BSP-H, the anticancer drug doxorubicin (DOX was covalently linked to branched polymer chains by reaction of primary amine of DOX and aldehyde groups in the polymer chains. Their compositions, structures, molecular weights, and molecular weight distributions were respectively characterized by nuclear magnetic resonance spectra and gel permeation chromatography measurements. The DOX-loaded micelles were fabricated by self-assembly of DOX-containing BSPs in water, which were characterized by transmission electron microscopy and dynamic light scattering. Aromatic imine linkage is stable in neutral water, but is acid-labile; controlled release of DOX from the BSP-H-DOX micelles was realized at pH values of 5 and 6, and at higher acidic solution, fast release of DOX was observed. In vitro cytotoxicity experiment results revealed low cytotoxicity of the BSPs and release of DOX from micelles in HepG2 and HeLa cells. Confocal laser fluorescence microscopy observations showed that DOX-loaded micelles have specific interaction with HepG2 cells. Thus, this type of BSP micelle is an efficient drug delivery system

  17. The NCI Delivery System for PDQ

    OpenAIRE

    1984-01-01

    The Physician Data Query System (PDQ) represents a major effort by the National Cancer Institute (NCI) to communicate advances in cancer treatment using computer technology. It utilizes a modern large scale computer mainframe to provide processing speed, a general purpose database management system to provide retrieval and display functions and flexibility, and commercial communications networks to provide access to an audience of physicians and other health care professionals seeking up-to-d...

  18. Review of Innovative Sediment Delivery Systems

    Science.gov (United States)

    2013-04-01

    analyzing site-specific hydrodynamics. The system employs numerical wave, current, and morphology models to optimize an offshore stockpile...refraction, and many other wave behaviors. TRANSPOR2004 is a sed- iment morphology model used for computation of sand transport under current and...CON World Systems, http://www.all-con.com/ newsletter /newsletter1.html. ACRONYMS AND ABBREVIATIONS. Term Definition CAS Conveyor Application

  19. Modeling, Estimation, and Control of Helicopter Slung Load System

    DEFF Research Database (Denmark)

    Bisgaard, Morten

    This thesis treats the subject of autonomous helicopter slung load flight and presents the reader with a methodology describing the development path from modeling and system analysis over sensor fusion and state estimation to controller synthesis. The focus is directed along two different....... To enable slung load flight capabilities for general cargo transport, an integrated estimation and control system is developed for use on already autonomous helicopters. The estimator uses vision based updates only and needs little prior knowledge of the slung load system as it estimates the length...... of the suspension system together with the system states. The controller uses a combined feedforward and feedback approach to simultaneously prevent exciting swing and to actively dampen swing in the slung load. For the mine detection application an estimator is developed that provides full system state information...

  20. Current Multistage Drug Delivery Systems Based on the Tumor Microenvironment

    Science.gov (United States)

    Chen, Binlong; Dai, Wenbing; He, Bing; Zhang, Hua; Wang, Xueqing; Wang, Yiguang; Zhang, Qiang

    2017-01-01

    The development of traditional tumor-targeted drug delivery systems based on EPR effect and receptor-mediated endocytosis is very challenging probably because of the biological complexity of tumors as well as the limitations in the design of the functional nano-sized delivery systems. Recently, multistage drug delivery systems (Ms-DDS) triggered by various specific tumor microenvironment stimuli have emerged for tumor therapy and imaging. In response to the differences in the physiological blood circulation, tumor microenvironment, and intracellular environment, Ms-DDS can change their physicochemical properties (such as size, hydrophobicity, or zeta potential) to achieve deeper tumor penetration, enhanced cellular uptake, timely drug release, as well as effective endosomal escape. Based on these mechanisms, Ms-DDS could deliver maximum quantity of drugs to the therapeutic targets including tumor tissues, cells, and subcellular organelles and eventually exhibit the highest therapeutic efficacy. In this review, we expatiate on various responsive modes triggered by the tumor microenvironment stimuli, introduce recent advances in multistage nanoparticle systems, especially the multi-stimuli responsive delivery systems, and discuss their functions, effects, and prospects. PMID:28255348

  1. Transferosomes - A vesicular transdermal delivery system for enhanced drug permeation

    Directory of Open Access Journals (Sweden)

    Reshmy Rajan

    2011-01-01

    Full Text Available Transdermal administration of drugs is generally limited by the barrier function of the skin. Vesicular systems are one of the most controversial methods for transdermal delivery of active substances. The interest in designing transdermal delivery systems was relaunched after the discovery of elastic vesicles like transferosomes, ethosomes, cubosomes, phytosomes, etc. This paper presents the composition, mechanisms of penetration, manufacturing and characterization methods of transferosomes as transdermal delivery systems of active substances. For a drug to be absorbed and distributed into organs and tissues and eliminated from the body, it must pass through one or more biological membranes/barriers at various locations. Such a movement of drug across the membrane is called as drug transport. For the drugs to be delivered to the body, they should cross the membranous barrier. The concept of these delivery systems was designed in an attempt to concentrate the drug in the tissues of interest, while reducing the amount of drug in the remaining tissues. Hence, surrounding tissues are not affected by the drug. In addition, loss of drug does not happen due to localization of drug, leading to get maximum efficacy of the medication. Therefore, the phospholipid based carrier systems are of considerable interest in this era.

  2. Calibration procedure of measuring system for vehicle wheel load estimation

    Science.gov (United States)

    Kluziewicz, M.; Maniowski, M.

    2016-09-01

    The calibration procedure of wheel load measuring system is presented. Designed method allows estimation of selected wheel load components while the vehicle is in motion. Mentioned system is developed to determine friction forces between tire and road surface, basing on measured internal reaction forces in wheel suspension mechanism. Three strain gauge bridges and three-component piezoelectric load cell are responsible for internal force measurement in suspension components, two wire sensors are measuring displacements. External load is calculated via kinematic model of suspension mechanism implemented in Matlab environment. In the described calibration procedure, internal reactions are measured on a test stand while the system is loaded by a force of known direction and value.

  3. Electrostatic wrapping of doxorubicin with curdlan to construct an efficient pH-responsive drug delivery system

    Science.gov (United States)

    Zhou, Jiang-Ling; Song, Fei; Tian, Jia-Feng; Nie, Wu-Cheng; Wang, Xiu-Li; Wang, Yu-Zhong

    2017-07-01

    The development of environmentally responsive drug delivery systems for the treatment of cancer has attracted particular interest in recent years. However, the enhancement of drug loading capacity and realization of pH-responsive drug delivery remain challenging. Herein, we employ carboxymethyl curdlan as a hydrophilic carrier to wrap doxorubicin (DOX) directly via electrostatic interaction. The sizes of the formed nanoparticles can be simply tuned by changing their feeding ratios. In particular, the nanoparticles are highly stable in aqueous solution without size variation. In vitro drug release and cytotoxicity assays illustrate that this delivery system can release DOX differentially under various environmental conditions and transport it into cell nuclei efficiently, with comparable therapeutic effect to the free drug. These results suggest that the carrying of antitumor drugs by polysaccharide via electrostatic interaction is a simple but effective way to construct a pH-dependent drug delivery platform.

  4. Foil system fatigue load environments for commercial hydrofoil operation

    Science.gov (United States)

    Graves, D. L.

    1979-01-01

    The hydrofoil fatigue loads environment in the open sea is examined. The random nature of wave orbital velocities, periods and heights plus boat heading, speed and control system design are considered in the assessment of structural fatigue requirements. Major nonlinear load events such as hull slamming and foil unwetting are included in the fatigue environment. Full scale rough water load tests, field experience plus analytical loads work on the model 929 Jetfoil commercial hydrofoil are discussed. The problem of developing an overall sea environment for design is defined. State of the art analytical approaches are examined.

  5. Optimizing flurbiprofen-loaded NLC by central composite factorial design for ocular delivery

    Science.gov (United States)

    Gonzalez-Mira, E.; Egea, M. A.; Souto, E. B.; Calpena, A. C.; García, M. L.

    2011-01-01

    The purpose of this study was to design and optimize a new topical delivery system for ocular administration of flurbiprofen (FB), based on lipid nanoparticles. These particles, called nanostructured lipid carriers (NLC), were composed of a fatty acid (stearic acid (SA)) as the solid lipid and a mixture of Miglyol® 812 and castor oil (CO) as the liquid lipids, prepared by the hot high pressure homogenization method. After selecting the critical variables influencing the physicochemical characteristics of the NLC (the liquid lipid (i.e. oil) concentration with respect to the total lipid (cOil/L (wt%)), the surfactant and the flurbiprofen concentration, on particle size, polydispersity index and encapsulation efficiency), a three-factor five-level central rotatable composite design was employed to plan and perform the experiments. Morphological examination, crystallinity and stability studies were also performed to accomplish the optimization study. The results showed that increasing cOil/L (wt%) was followed by an enhanced tendency to produce smaller particles, but the liquid to solid lipid proportion should not exceed 30 wt% due to destabilization problems. Therefore, a 70:30 ratio of SA to oil (miglyol + CO) was selected to develop an optimal NLC formulation. The smaller particles obtained when increasing surfactant concentration led to the selection of 3.2 wt% of Tween® 80 (non-ionic surfactant). The positive effect of the increase in FB concentration on the encapsulation efficiency (EE) and its total solubilization in the lipid matrix led to the selection of 0.25 wt% of FB in the formulation. The optimal NLC showed an appropriate average size for ophthalmic administration (228.3 nm) with a narrow size distribution (0.156), negatively charged surface (-33.3 mV) and high EE (~90%). The in vitro experiments proved that sustained release FB was achieved using NLC as drug carriers. Optimal NLC formulation did not show toxicity on ocular tissues.

  6. Optimizing flurbiprofen-loaded NLC by central composite factorial design for ocular delivery

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Mira, E; Egea, M A; Garcia, M L [Department of Physical Chemistry, Faculty of Pharmacy, Institute of Nanoscience and Nanotechnology, University of Barcelona, Avenida Joan XXIII s/n, E-08028 Barcelona (Spain); Souto, E B [Faculty of Health Sciences, Fernando Pessoa University, Rua Carlos da Maia, Nr. 296, Office S.1, P-4200-150 Porto (Portugal); Calpena, A C, E-mail: eligonzalezmi@ub.edu [Department of Biopharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of Barcelona, Avenida Joan XXIII s/n, E-08028 Barcelona (Spain)

    2011-01-28

    The purpose of this study was to design and optimize a new topical delivery system for ocular administration of flurbiprofen (FB), based on lipid nanoparticles. These particles, called nanostructured lipid carriers (NLC), were composed of a fatty acid (stearic acid (SA)) as the solid lipid and a mixture of Miglyol 812 and castor oil (CO) as the liquid lipids, prepared by the hot high pressure homogenization method. After selecting the critical variables influencing the physicochemical characteristics of the NLC (the liquid lipid (i.e. oil) concentration with respect to the total lipid (cOil/L (wt%)), the surfactant and the flurbiprofen concentration, on particle size, polydispersity index and encapsulation efficiency), a three-factor five-level central rotatable composite design was employed to plan and perform the experiments. Morphological examination, crystallinity and stability studies were also performed to accomplish the optimization study. The results showed that increasing cOil/L (wt%) was followed by an enhanced tendency to produce smaller particles, but the liquid to solid lipid proportion should not exceed 30 wt% due to destabilization problems. Therefore, a 70:30 ratio of SA to oil (miglyol + CO) was selected to develop an optimal NLC formulation. The smaller particles obtained when increasing surfactant concentration led to the selection of 3.2 wt% of Tween 80 (non-ionic surfactant). The positive effect of the increase in FB concentration on the encapsulation efficiency (EE) and its total solubilization in the lipid matrix led to the selection of 0.25 wt% of FB in the formulation. The optimal NLC showed an appropriate average size for ophthalmic administration (228.3 nm) with a narrow size distribution (0.156), negatively charged surface (-33.3 mV) and high EE ({approx}90%). The in vitro experiments proved that sustained release FB was achieved using NLC as drug carriers. Optimal NLC formulation did not show toxicity on ocular tissues.

  7. In vivo pharmacokinetics and biodistribution of resveratrol-loaded solid lipid nanoparticles for brain delivery.

    Science.gov (United States)

    Jose, S; Anju, S S; Cinu, T A; Aleykutty, N A; Thomas, S; Souto, E B

    2014-10-20

    Resveratrol is a potent anticancer. However, because of its low half-life (solid lipid nanoparticles (SLN) for resveratrol. SLN were prepared by solvent evaporation technique employing high speed homogenization followed by ultrasonication. SLN were designed at varying drug-lipid ratios (1:5, 1:9, 1:10, 1:11, 1:12 and 1:15) using Tween 80 or a combination of Tween 80 and polyvinyl alcohol (PVA) as surfactants. The mean particle size and zeta potential of the optimized formulation (drug-lipid ratio of 1:10) were 248.30 ± 3.80nm and -25.49 ± 0.49mV, respectively. The particle size and the encapsulation efficiency (EE) increased when varying the drug-lipid ratio from 1:5 to 1:15. Scanning electron microscopic (SEM) analysis showed that SLN were spherical in shape and had a smooth surface. The X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analyses revealed that the matrix of drug-loaded SLN was in disordered crystalline phase. The in vitro release study in phosphate buffer pH 7.4 followed a sustained release pattern. The drug release data was found to fit best into Higuchi kinetic model suggesting the diffusion controlled mechanism of drug release. The cytotoxicity assay (MAT) showed that SLN were equally effective (PSLN could significantly (PSLN serve as promising therapeutic systems to treat neoplastic diseases located in the brain tissue.

  8. Evolution of implantable and insertable drug delivery systems.

    Science.gov (United States)

    Kleiner, Lothar W; Wright, Jeremy C; Wang, Yunbing

    2014-05-10

    The paper describes the development of implantable and insertable drug delivery systems (IDDS) from their early stage in the 1960s until the current stage in the 2010s. It gives a detailed summary of non-degradable and biodegradable systems and their applications in different areas such as vascular disease treatment, birth control, cancer treatment, and eye disease treatment. It also describes the development of various implantable pump systems and some other atypical IDDS, the challenges and the future of IDDS.

  9. New perspectives on lipid and surfactant based drug delivery systems for oral delivery of poorly soluble drugs

    DEFF Research Database (Denmark)

    Müllertz, Anette; Ogbonna, Anayo; Ren, Shan

    2010-01-01

    The aim of this review is to highlight relevant considerations when implementing a rational strategy for the development of lipid and surfactant based drug delivery system and to discuss shortcomings and challenges to the current classification of these delivery systems. We also aim to offer...

  10. MICROEMULSIONS AS ANTIDIABETIC DRUG DELIVERY SYSTEMS

    Directory of Open Access Journals (Sweden)

    Omnia Sarhan, Mahmoud M. Ibrahim* and Mahmoud Mahdy

    2012-11-01

    Full Text Available Glibenclamide is practically insoluble in water and its gastrointestinal absorption is limited by its dissolution rate. Therefore, to enhance the drug dissolution and its hypoglycemic effects, the drug was formulated in different microemulsion systems and in vitro/in vivo evaluated. Microemulsion systems were prepared by Water titration method in which surfactants and cosurfactants (S/CoS were mixed at different weight ratios of 1:1, 2:1 and 3:1. They were subjected to transmission electron microscopical examination, pH determination and viscosity tests. The solubility of Glibenclamide in different microemulsion systems was determined. Forms 8, 9, 10, 11, 14 and 18 were found to have high Glibenclamide solubility using different oils. Form 11 and 9 showed the highest Glibenclamide release rates of 59.72% and 52.35%, respectively after 6 hours. In-vivo studies were tested using diabetic rats by application of form 11 with n-butanol as cosurfactant transdermally and form 8 with propylene glycol cosurfactant orally and transdermally. The results were compared to the drug suspension as a positive control. It was shown that microemulsion systems gave an effective tool of increasing drug dissolution probably due to enhanced wettability and reduced drug particle size, which in turn led to enhance its hypoglycemic effects.

  11. The new organization of the health care delivery system.

    Science.gov (United States)

    Shortell, S M; Hull, K E

    1996-01-01

    The U.S. health care system is restructuring at a dizzying pace. In many parts of the country, managed care has moved into third-generation models emphasizing capitated payment for enrolled lives and, in the process, turning most providers and institutions into cost centers to be managed rather than generators of revenue. While the full impact of the new managed care models remains to be seen, most evidence to date suggests that it tends to reduce inpatient use, may be associated with greater use of physician services and preventive care, and appears to result in no net differences either positive or negative with regard to quality or outcomes of care in comparison with fee-for-service plans. Some patients, however, tend to be somewhat less satisfied with scheduling of appointments and the amount of time spent with providers. There is no persuasive evidence that managed care lowers the rate of growth in overall health care costs within a given market. Further, managed care performance varies considerably across the country, and the factors influencing managed care performance are not well understood. Organized delivery systems are a somewhat more recent phenomenon representing various forms of ownership and strategic alliances among hospitals, physicians, and insurers designed to provide more cost-effective care to defined populations by achieving desired levels of functional, physician-system, and clinical integration. Early evidence suggests that organized delivery systems that are more integrated have the potential to provide more accessible coordinated care across the continuum, and appear to be associated with higher levels of inpatient productivity, greater total system revenue, greater total system cash flow, and greater total system operating margin than less integrated delivery forms. Some key success factors for developing organized delivery systems have been identified. Important roles are played by organizational culture, information systems, internal

  12. Organic Nanovesicular Cargoes for Sustained Drug Delivery: Synthesis, Vesicle Formation, Controlling “Pearling” States, and Terfenadine Loading/Release Studies

    Directory of Open Access Journals (Sweden)

    Ajay Kumar Botcha

    2014-01-01

    Full Text Available “Sustained drug delivery systems” which are designed to accomplish long-lasting therapeutic effect are one of the challenging topics in the area of nanomedicine. We developed an innovative strategy to prepare nontoxic and polymer stabilized organic nanovesicles (diameter: 200 nm from a novel bolaamphiphile, where two hydrogen bonding acetyl cytosine molecules connected to 4,4′′-positions of the 2,6-bispyrazolylpyridine through two flexible octyne chains. The nanovesicles behave like biological membrane by spontaneously self-assembling into “pearl-like” chains and subsequently forming long nanotubes (diameter: 150 nm, which further develop into various types of network-junctions through self-organization. For drug loading and delivery applications, the nanovesicles were externally protected with biocompatible poly(ethyleneglycol-2000 to prevent them from fusion and ensuing tube formation. Nontoxic nature of the nanovesicles was demonstrated by zebrafish teratogenicity assay. Biocompatible nanovesicles were loaded with “terfenadine” drug and successfully utilized to transport and release drug in sustained manner (up to 72 h in zebrafish larvae, which is recognized as an emerging in vivo model system.

  13. Modification of microbial polyacids for drug delivery systems

    OpenAIRE

    Lanz Landázuri, Alberto

    2014-01-01

    Polymers are becoming preferred materials in biomedical applications because of their vast diversity of properties, functionalities and applications. Properties as mechanical strength, stability against degradation, biocompatibility and biodegradability, among others, have been attractive for different medical applications. One of the most interesting applications of these materials is drug delivery systems. Biodegradable polymers and copolymers are the preferred materials for the manufacture...

  14. Novel targeted bladder drug-delivery systems: a review

    Directory of Open Access Journals (Sweden)

    Zacchè MM

    2015-11-01

    Full Text Available Martino Maria Zacchè, Sushma Srikrishna, Linda Cardozo Department of Urogynaecology, King's College Hospital, London, UK Abstract: The objective of pharmaceutics is the development of drugs with increased efficacy and reduced side effects. Prolonged exposure of the diseased tissue to the drug is of crucial importance. Drug-delivery systems (DDSs have been introduced to control rate, time, and place of release. Drugs can easily reach the bladder through a catheter, while systemically administered agents may undergo extensive metabolism. Continuous urine filling and subsequent washout hinder intravesical drug delivery (IDD. Moreover, the low permeability of the urothelium, also described as the bladder permeability barrier, poses a major challenge in the development of the IDD. DDSs increase bioavailability of drugs, therefore improving therapeutic effect and patient compliance. This review focuses on novel DDSs to treat bladder conditions such as overactive bladder, interstitial cystitis, bladder cancer, and recurrent urinary tract infections. The rationale and strategies for both systemic and local delivery methods are discussed, with emphasis on new formulations of well-known drugs (oxybutynin, nanocarriers, polymeric hydrogels, intravesical devices, encapsulated DDSs, and gene therapy. We give an overview of current and future prospects of DDSs for bladder disorders, including nanotechnology and gene therapy. Keywords: drug targeting, drug-delivery system, bladder disorders

  15. Magnetic microspheres as magical novel drug delivery system: A review

    Directory of Open Access Journals (Sweden)

    Satinder Kakar

    2013-01-01

    Full Text Available Magnetic microspheres hold great promise for reaching the goal of controlled and site specific drug delivery. Magnetic microspheres as an alternative to traditional radiation methods which uses highly penetrating radiations that is absorbed throughout the body. Its use is limited by toxicity and side effects. Now days, several targeted treatment systems including magnetic field, electric field, ultrasound, temperature, UV light and mechanical force are being used in many disease treatments (e.g. cancer, nerve damage, heart and artery, anti-diabetic, eye and other medical treatments. Among them, the magnetic targeted drug delivery system is one of the most attractive and promising strategy for delivering the drug to the specified site. Magnetically controlled drug targeting is one of the various possible ways of drug targeting. This technology is based on binding establish anticancer drug with ferrofluid that concentrate the drug in the area of interest (tumor site by means of magnetic fields. There has been keen interest in the development of a magnetically target drug delivery system. These drug delivery systems aim to deliver the drug at a rate directed by the needs of the body during the period of treatment, and target the activity entity to the site of action. Magnetic microspheres were developed to overcome two major problems encountered in drug targeting namely: RES clearance and target site specificity.

  16. Nanoparticulate Adjuvants and Delivery Systems for Allergen Immunotherapy

    Directory of Open Access Journals (Sweden)

    Juliana De Souza Rebouças

    2012-01-01

    Full Text Available In the last decades, significant progress in research and clinics has been made to offer possible innovative therapeutics for the management of allergic diseases. However, current allergen immunotherapy shows limitations concerning the long-term efficacy and safety due to local side effects and risk of anaphylaxis. Thus, effective and safe vaccines with reduced dose of allergen have been developed using adjuvants. Nevertheless, the use of adjuvants still has several disadvantages, which limits its use in human vaccines. In this context, several novel adjuvants for allergen immunotherapy are currently being investigated and developed. Currently, nanoparticles-based allergen-delivery systems have received much interest as potential adjuvants for allergen immunotherapy. It has been demonstrated that the incorporation of allergens into a delivery system plays an important role in the efficacy of allergy vaccines. Several nanoparticles-based delivery systems have been described, including biodegradable and nondegradable polymeric carriers. Therefore, this paper provides an overview of the current adjuvants used for allergen immunotherapy. Furthermore, nanoparticles-based allergen-delivery systems are focused as a novel and promising strategy for allergy vaccines.

  17. Nanocarriers for systemic siRNA delivery to tumor vasculature

    NARCIS (Netherlands)

    Yousefi, A.

    2014-01-01

    Currently there is a high need for efficacious medicines in cancer therapy. The use of conventional medicines to treat cancer is often hampered by their unfavorable safety profile which limits their dosing. By using targeted delivery systems, toxicity in non-target tissues can be reduced. An

  18. Orally disintegrating films: A modern expansion in drug delivery system

    Directory of Open Access Journals (Sweden)

    Muhammad Irfan

    2016-09-01

    Full Text Available Over the past few decades, tendency toward innovative drug delivery systems has majorly increased attempts to ensure efficacy, safety and patient acceptability. As discovery and development of new chemical agents is a complex, expensive and time consuming process, so recent trends are shifting toward designing and developing innovative drug delivery systems for existing drugs. Out of those, drug delivery system being very eminent among pediatrics and geriatrics is orally disintegrating films (ODFs. These fast disintegrating films have superiority over fast disintegrating tablets as the latter are associated with the risks of choking and friability. This drug delivery system has numerous advantages over conventional fast disintegrating tablets as they can be used for dysphasic and schizophrenic patients and are taken without water due to their ability to disintegrate within a few seconds releasing medication in mouth. Various approaches are employed for formulating ODFs and among which solvent casting and spraying methods are frequently used. Generally, hydrophilic polymers along with other excipients are used for preparing ODFs which allow films to disintegrate quickly releasing incorporated active pharmaceutical ingredient (API within seconds. Orally disintegrating films have potential for business and market exploitation because of their myriad of benefits over orally disintegrating tablets. This present review attempts to focus on benefits, composition, approaches for formulation and evaluation of ODFs. Additionally, the market prospect of this innovative dosage form is also targeted.

  19. Nanoparticulate adjuvants and delivery systems for allergen immunotherapy.

    Science.gov (United States)

    De Souza Rebouças, Juliana; Esparza, Irene; Ferrer, Marta; Sanz, María Luisa; Irache, Juan Manuel; Gamazo, Carlos

    2012-01-01

    In the last decades, significant progress in research and clinics has been made to offer possible innovative therapeutics for the management of allergic diseases. However, current allergen immunotherapy shows limitations concerning the long-term efficacy and safety due to local side effects and risk of anaphylaxis. Thus, effective and safe vaccines with reduced dose of allergen have been developed using adjuvants. Nevertheless, the use of adjuvants still has several disadvantages, which limits its use in human vaccines. In this context, several novel adjuvants for allergen immunotherapy are currently being investigated and developed. Currently, nanoparticles-based allergen-delivery systems have received much interest as potential adjuvants for allergen immunotherapy. It has been demonstrated that the incorporation of allergens into a delivery system plays an important role in the efficacy of allergy vaccines. Several nanoparticles-based delivery systems have been described, including biodegradable and nondegradable polymeric carriers. Therefore, this paper provides an overview of the current adjuvants used for allergen immunotherapy. Furthermore, nanoparticles-based allergen-delivery systems are focused as a novel and promising strategy for allergy vaccines.

  20. Targeted nanodrug delivery systems for the treatment of Tuberculosis

    CSIR Research Space (South Africa)

    Lemmer, Yolandy

    2010-06-01

    Full Text Available patient treatment compliance and drug resistance pose a great challenge to TB treatment programs worldwide. To improve the current inadequate therapeutic management of TB, a polymeric anti-TB nanodrug delivery system for anti-TB drugs was developed...

  1. Drug-Loaded Perfluorocarbon Nanodroplets for Ultrasound-Mediated Drug Delivery.

    Science.gov (United States)

    Rapoport, Natalya

    2016-01-01

    The interaction of nanoparticles with directed energy is a novel application in targeted drug delivery. This chapter focuses on perfluorocarbon nanoemulsions, whose action in drug delivery depends on the ultrasound-triggered phase shift from liquid to gaseous state. These nanoemulsions have great potential for unloading encapsulated drugs at a desired time and location in the body in response to directed ultrasound. In addition, they actively alter their nano-environment for enhancing drug transport through various biological barriers to sites of action, which significantly enhances therapeutic outcome.

  2. Application of Various Types of Liposomes in Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Mehran Alavi

    2017-04-01

    Full Text Available Liposomes, due to their various forms, require further exploration. These structures can deliver both hydrophilic and hydrophobic drugs for cancer, antibacterial, antifungal, immunomodulation, diagnostics, ophtalmica, vaccines, enzymes and genetic elements. Preparation of liposomes results in different properties for these systems. In addition, based on preparation methods, liposomes types can be unilamellar, multilamellar and giant unilamellar; however, there are many factors and difficulties that affect the development of liposome drug delivery structure. In the present review, we discuss some problems that impact drug delivery by liposomes. In addition, we discuss a new generation of liposomes, which is utilized for decreasing the limitation of the conventional liposomes.

  3. Application of Various Types of Liposomes in Drug Delivery Systems.

    Science.gov (United States)

    Alavi, Mehran; Karimi, Naser; Safaei, Mohsen

    2017-04-01

    Liposomes, due to their various forms, require further exploration. These structures can deliver both hydrophilic and hydrophobic drugs for cancer, antibacterial, antifungal, immunomodulation, diagnostics, ophtalmica, vaccines, enzymes and genetic elements. Preparation of liposomes results in different properties for these systems. In addition, based on preparation methods, liposomes types can be unilamellar, multilamellar and giant unilamellar; however, there are many factors and difficulties that affect the development of liposome drug delivery structure. In the present review, we discuss some problems that impact drug delivery by liposomes. In addition, we discuss a new generation of liposomes, which is utilized for decreasing the limitation of the conventional liposomes.

  4. Preparation and properties of BSA-loaded microspheres based on multi-(amino acid) copolymer for protein delivery.

    Science.gov (United States)

    Chen, Xingtao; Lv, Guoyu; Zhang, Jue; Tang, Songchao; Yan, Yonggang; Wu, Zhaoying; Su, Jiacan; Wei, Jie

    2014-01-01

    A multi-(amino acid) copolymer (MAC) based on ω-aminocaproic acid, γ-aminobutyric acid, L-alanine, L-lysine, L-glutamate, and hydroxyproline was synthetized, and MAC microspheres encapsulating bovine serum albumin (BSA) were prepared by a double-emulsion solvent extraction method. The experimental results show that various preparation parameters including surfactant ratio of Tween 80 to Span 80, surfactant concentration, benzyl alcohol in the external water phase, and polymer concentration had obvious effects on the particle size, morphology, and encapsulation efficiency of the BSA-loaded microspheres. The sizes of BSA-loaded microspheres ranged from 60.2 μm to 79.7 μm, showing different degrees of porous structure. The encapsulation efficiency of BSA-loaded microspheres also ranged from 38.8% to 50.8%. BSA release from microspheres showed the classic biphasic profile, which was governed by diffusion and polymer erosion. The initial burst release of BSA from microspheres at the first week followed by constant slow release for the next 7 weeks were observed. BSA-loaded microspheres could degrade gradually in phosphate buffered saline buffer with pH value maintained at around 7.1 during 8 weeks incubation, suggesting that microsphere degradation did not cause a dramatic pH drop in phosphate buffered saline buffer because no acidic degradation products were released from the microspheres. Therefore, the MAC microspheres might have great potential as carriers for protein delivery.

  5. In vitro and in vivo evaluation of ketotifen fumarate-loaded silicone hydrogel contact lenses for ocular drug delivery.

    Science.gov (United States)

    Xu, Jinku; Li, Xinsong; Sun, Fuqian

    2011-02-01

    The purpose of this work was to evaluate the usefulness of silicone hydrogel contact lenses loaded with ketotifen fumarate for ocular drug delivery. First, silicone contact lenses were prepared by photopolymerization of bitelechelic methacrylated polydimethylsiloxanes macromonomer, 3-methacryloxypropyltris(trimethylsiloxy)silane, and N,N-dimethylacrylamide using ethylene glycol dimethacrylate as a cross-linker and Darocur 1173 as an initiator followed by surface plasma treatment. Then, the silicone hydrogel matrices of the contact lenses were characterized by equilibrium swelling ratio (ESR), tensile tests, ion permeability, and surface contact angle. Finally, the contact lenses were loaded with ketotifen fumarate by pre-soaking in drug solution to evaluate drug loading capacity, in vitro and in vivo release behavior of the silicone contact lenses. The results showed that ESR and ion permeability increase, and the surface contact angle and tensile strength decreased with the increase of DMA component in the silicone hydrogel. The drug loading and in vitro releases were dependent on the hydrogel composition of hydrophilic/hydrophobic phase of the contact lenses. In rabbit eyes, the pre-soaked contact lenses sustained ketotifen fumarate release for more than 24 h, which leads to a more stable drug concentration and a longer mean retention time in tear fluid than that of eye drops of 0.05%.

  6. REVIEW ON FLOATING DRUG DELIVERY SYSTEMS: AN APPROACH TO ORAL CONTROLLED DRUG DELIVERY VIA GASTRIC RETENTION

    Directory of Open Access Journals (Sweden)

    Kadam Shashikant M

    2011-06-01

    Full Text Available Controlled release (CR dosage forms have been extensively used to improve therapy with many important drugs. Several approaches are currently utilized in prolongation of gastric residence time, including floating drug delivery system, swelling and expanding system, polymeric bioadhesive system, modified shape system, high density system and other delayed gastric emptying devices. However, the development processes are faced with several physiological difficulties such as the inability to restrain and localize the system within the desired region of the gastrointestinal tract and the highly variable nature of the gastric emptying process. On the other hand, incorporation of the drug in a controlled release gastroretentive dosage forms (CR-GRDF which can remain in the gastric region for several hours would significantly prolong the gastric residence time of drugs and improve bioavailability, reduce drug waste, and enhance the solubility of drugs that are less soluble in high pH environment. Gastroretention would also facilitate local drug delivery to the stomach and proximal small intestine. Thus, gastroretention could help to provide greater availability of new products and consequently improved therapeutic activity and substantial benefits to patients. The purpose of this paper is to review the recent literature and current technology used in the development of gastroretentive dosage forms.

  7. Steerable/distance enhanced penetrometer delivery system

    Energy Technology Data Exchange (ETDEWEB)

    Amini, A.; Boyd, G.M.

    1996-12-31

    Characterization, monitoring, and remediation of many of the nation`s highly contaminated sites are high priority at DOE. Penetrometers are often used for rapid characterization of underground contamination (plumes). Because of their heavy weight, use of penetrometer trucks over shallow buried storage tanks is restricted and risky. To close this gap, UTD developed a new position location device for penetrometers, called POLO (POsition LOcator), which provides real- time position location without blocking downhole access for environmental sensors. UTD also developed a system to make penetrometers steerable and capable of deeper penetration. Products of this work is a Steerable Vibratory System, which a relatively lightweight rig capable of greater penetration than traditional penetrometers of the same weight.

  8. Direct current power delivery system and method

    Science.gov (United States)

    Zhang, Di; Garces, Luis Jose; Dai, Jian; Lai, Rixin

    2016-09-06

    A power transmission system includes a first unit for carrying out the steps of receiving high voltage direct current (HVDC) power from an HVDC power line, generating an alternating current (AC) component indicative of a status of the first unit, and adding the AC component to the HVDC power line. Further, the power transmission system includes a second unit for carrying out the steps of generating a direct current (DC) voltage to transfer the HVDC power on the HVDC power line, wherein the HVDC power line is coupled between the first unit and the second unit, detecting a presence or an absence of the added AC component in the HVDC power line, and determining the status of the first unit based on the added AC component.

  9. Fluid delivery manifolds and microfluidic systems

    Energy Technology Data Exchange (ETDEWEB)

    Renzi, Ronald F.; Sommer, Gregory J.; Singh, Anup K.; Hatch, Anson V.; Claudnic, Mark R.; Wang, Ying-Chih; Van de Vreugde, James L.

    2017-02-28

    Embodiments of fluid distribution manifolds, cartridges, and microfluidic systems are described herein. Fluid distribution manifolds may include an insert member and a manifold base and may define a substantially closed channel within the manifold when the insert member is press-fit into the base. Cartridges described herein may allow for simultaneous electrical and fluidic interconnection with an electrical multiplex board and may be held in place using magnetic attraction.

  10. Novel drug-delivery systems for patients with chronic rhinosinusitis

    Directory of Open Access Journals (Sweden)

    Albu S

    2012-05-01

    Full Text Available Silviu AlbuDepartment of Otolaryngology, University of Medicine and Pharmacy Cluj-Napoca, Cluj-Napoca, RomaniaAbstract: Chronic rhinosinusitis, one of the most common chronic medical complaints in the United States, seems to be increasing in incidence and prevalence, and has a significant impact on quality of life. Topical forms of medical therapy represent an attractive alternative for drug delivery to the nasal cavity and paranasal sinuses. Topical drug delivery has the advantage of directly acting on the site of inflammation, producing a higher concentration at the target site while avoiding systemic side effects. Although considerable research has been undertaken into improving nasal formulations in order to enhance absorption, little attention has so far been directed to upgrading the delivery devices. The aim of this review is to present current knowledge on the novel drug-delivery devices in use in the management of chronic rhinosinusitis patients, and to present the current available knowledge on topical drug penetration into the sinuses using various delivery devices. Additionally, methods used to enhance fluid sinus deposition are presented and the published clinical studies on the results of nebulized antibiotics in the treatment of chronic rhinosinusitis patients are discussed.Keywords: paranasal sinuses, topical therapy, nebulized antibiotics, clinical trials

  11. Drug Delivery Systems, CNS Protection, and the Blood Brain Barrier

    Directory of Open Access Journals (Sweden)

    Ravi Kant Upadhyay

    2014-01-01

    Full Text Available Present review highlights various drug delivery systems used for delivery of pharmaceutical agents mainly antibiotics, antineoplastic agents, neuropeptides, and other therapeutic substances through the endothelial capillaries (BBB for CNS therapeutics. In addition, the use of ultrasound in delivery of therapeutic agents/biomolecules such as proline rich peptides, prodrugs, radiopharmaceuticals, proteins, immunoglobulins, and chimeric peptides to the target sites in deep tissue locations inside tumor sites of brain has been explained. In addition, therapeutic applications of various types of nanoparticles such as chitosan based nanomers, dendrimers, carbon nanotubes, niosomes, beta cyclodextrin carriers, cholesterol mediated cationic solid lipid nanoparticles, colloidal drug carriers, liposomes, and micelles have been discussed with their recent advancements. Emphasis has been given on the need of physiological and therapeutic optimization of existing drug delivery methods and their carriers to deliver therapeutic amount of drug into the brain for treatment of various neurological diseases and disorders. Further, strong recommendations are being made to develop nanosized drug carriers/vehicles and noninvasive therapeutic alternatives of conventional methods for better therapeutics of CNS related diseases. Hence, there is an urgent need to design nontoxic biocompatible drugs and develop noninvasive delivery methods to check posttreatment clinical fatalities in neuropatients which occur due to existing highly toxic invasive drugs and treatment methods.

  12. Unsteady jet in designing innovative drug delivery system

    Science.gov (United States)

    Wang, Cong; Mazur, Paul; Cosse, Julia; Rider, Stephanie; Gharib, Morteza

    2014-11-01

    Micro-needle injections, a promising pain-free drug delivery method, is constrained by its limited penetration depth. This deficiency can be overcome by implementing fast unsteady jet that can penetrate sub-dermally. The development of a faster liquid jet would increase the penetration depth and delivery volume of micro-needles. In this preliminary work, the nonlinear transient behavior of an elastic tube balloon in providing fast discharge is analyzed. A physical model that combines the Mooney Rivlin Material model and Young-Lapalce's Law was developed and used to investigate the fast discharging dynamic phenomenon. A proof of concept prototype was constructed to demonstrate the feasibility of a simple thumb-sized delivery system to generate liquid jet with desired speed in the range of 5-10 m/s. This work is supported by ZCUBE Corporation.

  13. Crystallization Methods for Preparation of Nanocrystals for Drug Delivery System.

    Science.gov (United States)

    Gao, Yuan; Wang, Jingkang; Wang, Yongli; Yin, Qiuxiang; Glennon, Brian; Zhong, Jian; Ouyang, Jinbo; Huang, Xin; Hao, Hongxun

    2015-01-01

    Low water solubility of drug products causes delivery problems such as low bioavailability. The reduced particle size and increased surface area of nanocrystals lead to the increasing of the dissolution rate. The formulation of drug nanocrystals is a robust approach and has been widely applied to drug delivery system (DDS) due to the significant development of nanoscience and nanotechnology. It can be used to improve drug efficacy, provide targeted delivery and minimize side-effects. Crystallization is the main and efficient unit operation to produce nanocrystals. Both traditional crystallization methods such as reactive crystallization, anti-solvent crystallization and new crystallization methods such as supercritical fluid crystallization, high-gravity controlled precipitation can be used to produce nanocrystals. The current mini-review outlines the main crystallization methods addressed in literature. The advantages and disadvantages of each method were summarized and compared.

  14. Dual drug delivery from vitamin E loaded contact lenses for glaucoma therapy.

    Science.gov (United States)

    Hsu, Kuan-Hui; Carbia, Blanca E; Plummer, Caryn; Chauhan, Anuj

    2015-08-01

    Glaucoma patients frequently instill eye drops multiple times each day, which is a cause for reduced compliance. Additionally, eye drops suffer from other limitations including low bioavailability, which can lead to side effects. We propose to develop drug-eluting contact lenses for managing glaucoma with increased bioavailability and improved compliance. Contact lenses are developed for extended simultaneous release of timolol and dorzolamide, both of which are commonly prescribed hydrophilic drugs. The extended release is achieved by loading lenses with vitamin E barriers. In vitro release studies are performed with control and vitamin E loaded lenses for both drugs loaded separately and then together in the same lens. The safety and efficacy of combination therapy by contacts are demonstrated in a Beagle model of glaucoma. Simultaneous loading of timolol and dorzolamide increases the release duration of both drugs. Also vitamin E incorporation is highly effective in increasing the release durations of both drugs to about 2-days. The lenses loaded with both drugs exhibited superior IOP reduction compared to eye drops with about 6-fold lower drug loading. More importantly, combination therapy by continuous wear of vitamin E loaded contact for 2-days, followed by a new set of contacts for another two days, reduced IOP during the 4days of wear time and for another 8days after removal of the contacts. Vitamin E loading is very effective for providing combination therapy by contact lenses due to the increase in release durations of several drugs. The contact lens based therapy reduces IOP with lower drug dose compared to eye drops and may significantly improve the compliance as the effect of the therapy lasts significantly longer than the wear-duration.

  15. Syngonanthus nitens Bong. (Rhul.-Loaded Nanostructured System for Vulvovaginal Candidiasis Treatment

    Directory of Open Access Journals (Sweden)

    Matheus Aparecido dos Santos Ramos

    2016-08-01

    Full Text Available Herbal-loaded drug delivery nanotechnological systems have been extensively studied recently. The antimicrobial activity of medicinal plants has shown better pharmacological action when such plants are loaded into a drug delivery system than when they are not loaded. Syngonanthus nitens Bong. (Rhul. belongs to the Eriocaulaceae family and presents antiulcerogenic, antioxidant, antibacterial, and antifungal activity. The aim of this study was to evaluate the antifungal activity of Syngonanthus nitens (S. nitens extract that was not loaded (E or loaded (SE into a liquid crystal precursor system (S for the treatment of vulvovaginal candidiasis (VVC with Candida albicans. The minimal inhibitory concentration (MIC was determined by the microdilution technique. Additionally, we performed hyphae inhibition and biofilm tests. Finally, experimental candidiasis was evaluated in in vivo models with Wistar female rats. The results showed effective antifungal activity after incorporation into S for all strains tested, with MICs ranging from 31.2 to 62.5 μg/mL. Microscopic observation of SE revealed an absence of filamentous cells 24 h of exposure to a concentration of 31.2 μg/mL. E demonstrated no effective action against biofilms, though SE showed inhibition against biofilms of all strains. In the in vivo experiment, SE was effective in the treatment of infection after only two days of treatment and was more effective than E and amphotericin B. The S. nitens is active against Candida albicans (C. albicans and the antifungal potential is being enhanced after incorporation into liquid crystal precursor systems (LCPS. These findings represent a promising application of SE in the treatment of VVC.

  16. The study of new anticancer drug delivery system based on the boron nitride nanoparticles

    Directory of Open Access Journals (Sweden)

    I. Yu. Zhitnyak

    2016-01-01

    Full Text Available The main problem in the treatment of many cancers is multidrug resistance due to tumor progression. Using nanosized drug delivery systems allows to overcome the mechanisms of multidrug resistance of cancer, in this case, chemotherapeutic agents can effectively introduce into cancer cells by endocytosis and accumulate near the nucleus and far from ATP-binding cassette transporters. Creation of boron nitridebased drug delivery nanocarriers with high chemical and oxidative stability is one of the perspective ways. Using chemical vapor deposition spherical boron nitride particles,100–150 nm in diameter (BNNPs, with peculiar petal-like surfaces or smooth surfaces were fabricated. BNNPs were loaded with doxorubicin. Drug loading efficacy of BNNPs-DOX was about 0.095 mg/mg of particles. BNNPs-DOX were relatively stable at neutral pH, whereas DOX is effectively released from the BNNPs at acidic pH (pH 4.5–5.5. Using confocal microscopy, the uptake of BNNPs-DOX by IAR-6-1, KB-3-1, К562 cells and multidrug resistant КВ-8-5 и IS-9 cells was studied. Most of BNNPs-DOX had been co-localized with LysoTracker, indicating that BNNPs-DOX are located in the endosomes/lysosomes after intracellular delivery.

  17. Magnetic responsive of paclitaxel delivery system based on SPION and palmitoyl chitosan

    Science.gov (United States)

    Mansouri, Mona; Nazarpak, Masoumeh Haghbin; Solouk, Atefeh; Akbari, Somaye; Hasani-Sadrabadi, Mohammad Mahdi

    2017-01-01

    Concerns over cancer treatment have largely focused on chemotherapy and its consequent side effects. Utilizing nanocarriers is thought to be a panacea for mitigating the limitations of chemotherapy, and increasing its safety and efficacy. Magnetically driven Paclitaxel delivery systems are among the commonly investigated types of nanocarriers over the last two decades. In this context, we tried to highlight the application of an AC magnetic field and validate its consequential effects on drug delivery pattern and cell death in such nanodevices. So the aim of this study is to develop an appropriate matrix (Palmitoyl chitosan) co-encapsulated with superparamagnetic iron oxide nanoparticles (SPIONs) and anticancer drug, Paclitaxel (PTX) via the nanoprecipitation process. Synthesized nanoparticles were characterized by Dynamic Light Scattering (DLS) and their magnetic properties were investigated by Vibrating Sample Magnetometer (VSM). At initial loading of 10 wt% Paclitaxel, the maximum loading efficiency of nanoparticles with and without SPIONs was in the range of 69% and 72.3%, respectively. In addition, in vitro release data revealed that by the application of a magnetic field, release kinetic changed to the magnetic responsive pattern. Encapsulating anticancer drug in a synthesized nanosystem not only increased the amount of drug in cancer cells but also enhanced cell death (MCF-7) due to hyperthermic effects of SPIONs in the presence of an external magnetic field. In summary, these findings indicate that the resultant nanoparticles may serve as a biocompatible and biodegradable carrier for the precise delivery of powerful cytotoxic anticancer agents such as PTX.

  18. Preparation and physicochemical characterization of supercritically dried insulin-loaded microparticles for pulmonary delivery

    NARCIS (Netherlands)

    Amidi, Maryam; Pellikaan, Hubert C.; de Boer, Anne H.; Crommelin, Daan J. A.; Hennink, Wim E.; Jiskoot, Wim

    In the search for non-invasive delivery options for the increasing number of therapeutic proteins, pulmonary administration is an attractive route. Supercritical fluid (SCF) drying processes offer the possibility to produce dry protein formulations suitable for inhalation. In this study,

  19. Preparation and physicochemical characterization of supercritically dried insulin-loaded microparticles for pulmonary delivery

    NARCIS (Netherlands)

    Amidi, Maryam; Pellikaan, Hubert C.; de Boer, Anne H.; Crommelin, Daan J. A.; Hennink, Wim E.; Jiskoot, Wim

    2008-01-01

    In the search for non-invasive delivery options for the increasing number of therapeutic proteins, pulmonary administration is an attractive route. Supercritical fluid (SCF) drying processes offer the possibility to produce dry protein formulations suitable for inhalation. In this study, insulin-loa

  20. Self emulsifying drug delivery system (SEDDS) for phytoconstituents: a review.

    Science.gov (United States)

    Chouhan, Neeraj; Mittal, Vineet; Kaushik, Deepak; Khatkar, Anurag; Raina, Mitali

    2015-01-01

    The self emulsifying drug delivery system (SEDDS) is considered to be the novel technique for the delivery of lipophillic plant actives. The self emulsifying (SE) formulation significantly enhance the solubility and bioavailability of poorly aqueous soluble phytoconstituents. The self emulsifying drug delivery system (SEDDS) can be developed for such plant actives to enhance the oral bioavailability using different excipients (lipid, surfactant, co solvent etc.) and their concentration is selected on the basis of pre formulation studies like phase equilibrium studies, solvent capacity of oil for drug and mutual miscibility of excipients. The present review focuses mainly on the development of SEDDS and effect of excipients on oral bioavailability and aqueous solubility of poorly water soluble phytoconstituents/ derived products. A recent list of patents issued for self emulsifying herbal formulation has also been included. The research data for various self emulsifying herbal formulation and patents issued were reviewed using different databases such as PubMed, Google Scholar, Google patents, Scopus and Web of Science. In a nutshell, we can say that SEDDS was established as a novel drug delivery system for herbals and with the advances in this technique, lots of patents on herbal SEDDS can be translated into the commercial products.

  1. Chitosan nanoparticle based delivery systems for sustainable agriculture.

    Science.gov (United States)

    Kashyap, Prem Lal; Xiang, Xu; Heiden, Patricia

    2015-01-01

    Development of technologies that improve food productivity without any adverse impact on the ecosystem is the need of hour. In this context, development of controlled delivery systems for slow and sustained release of agrochemicals or genetic materials is crucial. Chitosan has emerged as a valuable carrier for controlled delivery of agrochemicals and genetic materials because of its proven biocompatibility, biodegradability, non-toxicity, and adsorption abilities. The major advantages of encapsulating agrochemicals and genetic material in a chitosan matrix include its ability to function as a protective reservoir for the active ingredients, protecting the ingredients from the surrounding environment while they are in the chitosan domain, and then controlling their release, allowing them to serve as efficient gene delivery systems for plant transformation or controlled release of pesticides. Despite the great progress in the use of chitosan in the area of medical and pharmaceutical sciences, there is still a wide knowledge gap regarding the potential application of chitosan for encapsulation of active ingredients in agriculture. Hence, the present article describes the current status of chitosan nanoparticle-based delivery systems in agriculture, and to highlight challenges that need to be overcome. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Interpenetrating Polymer Networks as Innovative Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Alka Lohani

    2014-01-01

    Full Text Available Polymers have always been valuable excipients in conventional dosage forms, also have shown excellent performance into the parenteral arena, and are now capable of offering advanced and sophisticated functions such as controlled drug release and drug targeting. Advances in polymer science have led to the development of several novel drug delivery systems. Interpenetrating polymer networks (IPNs have shown superior performances over the conventional individual polymers and, consequently, the ranges of applications have grown rapidly for such class of materials. The advanced properties of IPNs like swelling capacity, stability, biocompatibility, nontoxicity and biodegradability have attracted considerable attention in pharmaceutical field especially in delivering bioactive molecules to the target site. In the past few years various research reports on the IPN based delivery systems showed that these carriers have emerged as a novel carrier in controlled drug delivery. The present review encompasses IPNs, their types, method of synthesis, factors which affects the morphology of IPNs, extensively studied IPN based drug delivery systems, and some natural polymers widely used for IPNs.

  3. Nanoparticle-based drug delivery systems: promising approaches against infections

    Energy Technology Data Exchange (ETDEWEB)

    Ranghar, Shweta; Sirohi, Parul [Department of Applied Mechanics, Motilal Nehru National Institute of Technology, Allahabad (India); Verma, Pritam; Agarwal, Vishnu, E-mail: vishnu_agarwal02@rediffmail.com [Department of Biotechnology, Motilal Nehru National Institute of Technology, Allahabad (India)

    2014-03-15

    Despite the fact that many new drugs and technologies have been developed to combat the infectious diseases, these have continued to be global health challenges. The use of conventional antimicrobial agents against these infections is always associated with problems such as the development of multiple drug resistance and adverse side effects. In addition, the inefficient traditional drug delivery system results in inadequate therapeutic index, low bioavailability of drugs and many other limitations. In this regard, antimicrobial nanoparticles and nanosized drug delivery carriers have emerged as potent effective agents against the infections. Nanoparticles have unique properties owing to their ultra small and controllable size such as high surface area, enhanced reactivity, and functionalizable structure. This review focused on different classes of antimicrobial nanoparticles, including metal, metal oxide and others along with their mechanism of action and their potential use against the infections. The review also focused on the development of nanoparticle systems for antimicrobial drug delivery and use of these systems for delivery of various antimicrobial agents, giving an overview about modern nanoparticle based therapeutic strategies against the infections. (author)

  4. 盐酸倍他洛尔蒙脱石微球的制备及其体外释放性能的研究%Study on the preparation and in vitro release behavior of the ion exchange drug de-livery system microspheres with a novel carrier of montmorillonite loaded with bet-axolol hydrochloride

    Institute of Scientific and Technical Information of China (English)

    侯冬枝; 龙诗越; 刘莉; 潘育方; 平其能; 梁婷丽; 冯开钰; 莫俭

    2014-01-01

    Obj ective Betaxolol hydrochloride microspheres loaded by montmorillonite with appropriate release rate were prepared in this study.Methods Formulation and preparation parameters of the ion exchange drug delivery system microspheres with a novel carrier of montmorillonite loaded with betaxolol hydrochloride were prepared by S/O1/O2/O3 emulsion solvent evaporation meth-od.Release behaviors invitro were demonstrated for the controlled release of water-soluble drug betaxolol hydrochloride(BH).To optimize the formulations,influence factors of polymer concentration of Eudragit RS,volume ratio of dispersed phase visus oil, drug concentration,and surfactant concentration were studied.Results The spherical and smooth microspheres were achieved with a mono dispersibility,and could release invitro as long as 10 h without burst release.Polymer concentration,volume ratio of dis-persed phase had significant influence on the release behavior.The optimized formulation was oil∶ drug=6∶1 ,drug∶polymer=1∶5,and composed with 0.5%-2% surfactants.Conclusion Betaxolol hydrochloride microspheres with appropriate release rate were achieved by S/O1/O2/O3 emulsion solvent evaporation preparation in this study.%目的:制备可满足缓释要求的镶嵌蒙脱石的离子交换缓释微球。方法采用 S/O1/O2/O3复乳-溶剂挥发法制备微球,考察处方因素包括复乳相体积比例、药物质量浓度、膜材用量和乳化剂质量分数对微球制备的影响。以微球体外释放为考察指标,优化微球处方。结果研究所得到的微球最佳处方为大豆油∶药物=6∶1,药物∶膜材=1∶5,乳化剂质量分数为0.5%~2%。除乳化剂外,其他因素对微球体外释放均有较大影响。所制备微球的体外释放可以达到10 h,基本无突释现象。进行形态观察发现,微球较为圆整,粒径比较均匀。结论采用优化处方以复乳-溶剂挥发法所制备盐酸倍他洛尔蒙脱石微球体外具有缓释性能。

  5. Holomorphic Embedded Load Flow for autonomous spacecraft power systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Holomorphic Embedding Load Flow Method (HELM) is a breakthrough that brings significant advances to the field of power systems. It provides a non-iterative...

  6. Power quality load management for large spacecraft electrical power systems

    Science.gov (United States)

    Lollar, Louis F.

    1988-01-01

    In December, 1986, a Center Director's Discretionary Fund (CDDF) proposal was granted to study power system control techniques in large space electrical power systems. Presented are the accomplishments in the area of power system control by power quality load management. In addition, information concerning the distortion problems in a 20 kHz ac power system is presented.

  7. Transdermal delivery of low molecular weight heparin loaded in flexible liposomes with bioavailability enhancement: comparison with ethosomes.

    Science.gov (United States)

    Song, Yun-Kyoung; Hyun, Seo Yeon; Kim, Hyung-Tae; Kim, Chong-Kook; Oh, Jung-Mi

    2011-01-01

    Low molecular weight heparin (LMWH)-loaded flexible liposomes (flexosomes) were formulated for transdermal delivery, and their physicochemical and pharmacokinetic parameters were compared with LMWH-loaded ethosomes. Flexosomes had similar particle size compared with ethosomes, but their deformability was higher than that of ethosomes (76.7% vs. 46.8%). In vitro, flexosomes demonstrated 2.6-fold higher permeability coefficient than ethosomes. In comparison to LMWH aqueous solution, skin deposition of flexosome increased 3.2-fold, while that of ethosome increased only 2.0-fold. In vivo, after the topical application of flexosome to hairless mouse, [anti-Xa](max) was 1.11 IU/mL, while ethosomes showed only 0.32 IU/mL. Moreover, AUC(0-24 h) of flexosomes was 2.5-fold higher than ethosomes. In conclusion, the enhanced skin permeation and bioavailability of LMWH can be achieved with flexosomes in comparison with ethosomes. The LMWH transdermal delivery via flexosomes has the potential to replace the parenteral dosage forms for the treatment of venous thromboembolism, pulmonary embolism and cardiovascular events.

  8. A Colon Targeted Delivery System for Resveratrol Enriching in pH Responsive-Model

    DEFF Research Database (Denmark)

    Andishmand, Hashem; Hamishehkar, Hamed; Babazadeh, Afshin

    2017-01-01

    , protects resveratrol from oxidation and isomerization, and delivers it to the colon is a priority of food and drug industry. In this study, resveratrol-polyethylene glycol (PEG)-loaded pectin-chitosan polyelectrolyte complex was designed as a colon targeted delivery system. Methods: The effects of adding...... PEG, ultra-sonication time, pH, and pectin to chitosan ratio were investigated on particle size, polydispersity index (PDI), zeta potential by particle size analyzer, and scanning electron microscopy (SEM). Encapsulation efficiency (EE), release of resveratrol in simulated gastrointestinal fluid...

  9. Efficient load rebalancing for distributed file system in Clouds

    Directory of Open Access Journals (Sweden)

    Mr. Mohan S. Deshmukh

    2016-05-01

    Full Text Available Cloud computing is an upcoming era in software industry. It’s a very vast and developing technology. Distributed file systems play an important role in cloud computing applications based on map reduce techniques. While making use of distributed file systems for cloud computing, nodes serves computing and storage functions at the same time. Given file is divided into small parts to use map reduce algorithms in parallel. But the problem lies here since in cloud computing nodes may be added, deleted or modified any time and also operations on files may be done dynamically. This causes the unequal load distribution of load among the nodes which leads to load imbalance problem in distributed file system. Newly developed distributed file system mostly depends upon central node for load distribution but this method is not helpful in large-scale and where chances of failure are more. Use of central node for load distribution creates a problem of single point dependency and chances of performance of bottleneck are more. As well as issues like movement cost and network traffic caused due to migration of nodes and file chunks need to be resolved. So we are proposing algorithm which will overcome all these problems and helps to achieve uniform load distribution efficiently. To verify the feasibility and efficiency of our algorithm we will be using simulation setup and compare our algorithm with existing techniques for the factors like load imbalance factor, movement cost and network traffic.

  10. Fuzzy controller for a system with uncertain load

    DEFF Research Database (Denmark)

    Kulczycki, P.; Wisniewski, Rafal

    2002-01-01

    in engineering solutions. The present paper deals with the time-optimal control for mechanical systems with uncertain load. A fuzzy approach is used in the design of suboptimal feedback controllers, robust with respect to the load. The methodology proposed in this work may be easily adapted to other modeling......In many applications of motion control, problems associated with imprecisely measured or changing load (a mass or a moment of inertia) can be a serious obstacle in the formation of satisfactory controlling systems. This barrier compels the designer to include various kinds of uncertainties...

  11. Novel load balancing DHT scheme for the heterogeneous system

    Institute of Scientific and Technical Information of China (English)

    Li Yujun; Lu Xianliang; Hou Mengshu

    2008-01-01

    The capacities of the nodes in the peer-to-peer system are strongly heterogeneous,hence one can benefit from distributing the load.based on the capacity of the nodes.At first a model is discussed to evaluate the load balancing of the heterogeneous system,and then a novel load balancing scheme is proposed based on the concept of logical servers and the randomized binary tree,and theoretical guarantees are given.Finally,the feasibility of the scheme using extensive simulations is proven.

  12. Carbon nanotubes as a novel drug delivery system for anticancer therapy: a review

    Energy Technology Data Exchange (ETDEWEB)

    Kushwaha, Swatantra Kumar Singh; Ghoshal, SauravI; Rai, Awani Kumar, E-mail: swatantrakushwaha@yahoo.co.in [Pranveer Singh Institute of Technology, Kanpur (India); Singh, Satyawan [Saroj Institute of Technology and Management, Lucknow (India)

    2013-10-15

    Carbon nanotubes (CNTs) were discovered in 1991 and shown to have certain unique physicochemical properties, attracting considerable interest in their application in various fields including drug delivery. The unique properties of CNTs such as ease of cellular uptake, high drug loading, thermal ablation, among others, render them useful for cancer therapy. Cancer is one of the most challenging diseases of modern times because its therapy involves distinguishing normal healthy cells from affected cells. Here, CNTs play a major role because phenomena such as EPR, allow CNTs to distinguish normal cells from affected ones, the Holy Grail in cancer therapy. Considerable work has been done on CNTs as drug delivery systems over the last two decades. However, concerns over certain issues such as biocompatibility and toxicity have been raised and warrant extensive research in this field. (author)

  13. Carbon nanotubes as a novel drug delivery system for anticancer therapy: a review

    Directory of Open Access Journals (Sweden)

    Swatantra Kumar Singh Kushwaha

    2013-12-01

    Full Text Available Carbon nanotubes (CNTs were discovered in 1991 and shown to have certain unique physicochemical properties, attracting considerable interest in their application in various fields including drug delivery. The unique properties of CNTs such as ease of cellular uptake, high drug loading, thermal ablation, among others, render them useful for cancer therapy. Cancer is one of the most challenging diseases of modern times because its therapy involves distinguishing normal healthy cells from affected cells. Here, CNTs play a major role because phenomena such as EPR, allow CNTs to distinguish normal cells from affected ones, the Holy Grail in cancer therapy. Considerable work has been done on CNTs as drug delivery systems over the last two decades. However, concerns over certain issues such as biocompatibility and toxicity have been raised and warrant extensive research in this field.

  14. Applications of polymers in intraocular drug delivery systems

    Science.gov (United States)

    Alhalafi, Ali Mohammed

    2017-01-01

    We are entering a new era of ophthalmic pharmacology where new drugs are rapidly being developed for the treatment of anterior and posterior segment of the eye disease. The pharmacokinetics of drug delivery to the eye remains a very active area of ophthalmic research. Intraocular drug delivery systems allow the release of the drug, bypassing the blood-ocular barrier. The main advantage of these preparations is that they can release the drug over a long time with one single