The Experts below are selected from a list of 162 Experts worldwide ranked by ideXlab platform
Alejandro Sánchez - One of the best experts on this subject based on the ideXlab platform.
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Sorbitan Ester nanoparticles sens as a novel topical ocular drug delivery system design optimization and in vitro ex vivo evaluation
International Journal of Pharmaceutics, 2018Co-Authors: Antonio Lopezgarcia, Jesus Alvareztrabado, Manuel Martinpastor, Yolanda Diebold, Alejandro SánchezAbstract:Abstract We explored the potential of two types of Sorbitan Ester nanoparticles (SENS) as novel tools for topical ocular drug delivery. The optimized SENS formulation (SENS-OPT) consisted of nanoparticles (NPs) of 170.5 nm, zeta potential +33.9 mV, and cyclosporine loading of 19.66%. After hyaluronic acid (HA) coating, the resulting SENS-OPT-HA NPs had a particle size of 177.6 nm and zeta potential of −20.6 mV. The NPs were stable during 3 months of storage at different temperatures and did not aggregate in the presence of protein-enriched simulated lacrimal fluid. There was no toxicity to cultured human corneal epithelial (HCE) cells when exposed to NPs up to 0.4% (w/v). Both NPs were effectively internalized by HCE cells through active mechanisms. Endocytosis of SENS-OPT NPs was caveolin-dependent whereas SENS-OPT-HA NP endocytosis was mediated by HA receptors. HA-receptor–mediated endocytosis may be responsible for the higher cellular uptake of SENS-OPT-HA NPs. After cyclosporine incorporation into the NPs, corneal penetration of this immunosuppressive drug by loaded SENS-OPT NPs was 1.3-fold higher than the commercial reference formulation Sandimmun®. For cyclosporine-loaded SENS-OPT-HA NPs, the penetration was 2.1-fold higher than for Sandimmun®. In ex vivo stimulated lymphocytes, both formulations demonstrated the same reduction in IL-2 levels as Sandimmun®.
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Sorbitan Ester nanoparticles (SENS) as a novel topical ocular drug delivery system: Design, optimization, and in vitro/ex vivo evaluation
International Journal of Pharmaceutics, 2018Co-Authors: Jesus Alvarez-trabado, Yolanda Diebold, Antonio López-garcía, Manuel Martín-pastor, Alejandro SánchezAbstract:Abstract We explored the potential of two types of Sorbitan Ester nanoparticles (SENS) as novel tools for topical ocular drug delivery. The optimized SENS formulation (SENS-OPT) consisted of nanoparticles (NPs) of 170.5 nm, zeta potential +33.9 mV, and cyclosporine loading of 19.66%. After hyaluronic acid (HA) coating, the resulting SENS-OPT-HA NPs had a particle size of 177.6 nm and zeta potential of −20.6 mV. The NPs were stable during 3 months of storage at different temperatures and did not aggregate in the presence of protein-enriched simulated lacrimal fluid. There was no toxicity to cultured human corneal epithelial (HCE) cells when exposed to NPs up to 0.4% (w/v). Both NPs were effectively internalized by HCE cells through active mechanisms. Endocytosis of SENS-OPT NPs was caveolin-dependent whereas SENS-OPT-HA NP endocytosis was mediated by HA receptors. HA-receptor–mediated endocytosis may be responsible for the higher cellular uptake of SENS-OPT-HA NPs. After cyclosporine incorporation into the NPs, corneal penetration of this immunosuppressive drug by loaded SENS-OPT NPs was 1.3-fold higher than the commercial reference formulation Sandimmun®. For cyclosporine-loaded SENS-OPT-HA NPs, the penetration was 2.1-fold higher than for Sandimmun®. In ex vivo stimulated lymphocytes, both formulations demonstrated the same reduction in IL-2 levels as Sandimmun®.
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Development and characterisation of chondroitin sulfate- and hyaluronic acid-incorporated Sorbitan Ester nanoparticles as gene delivery systems.
European Journal of Pharmaceutics and Biopharmaceutics, 2018Co-Authors: I. Fernandez-piñeiro, Andrea Pensado, Iker Badiola, Alejandro SánchezAbstract:Abstract Glycosaminoglycans (GAGs) are natural polymers that are broadly used in gene delivery systems to increase stability as well as decrease toxicity and nonspecific interactions, thereby increasing transfection efficiency. In this work, we propose Sorbitan Ester-based lipid nanoparticles (SENS) functionalised with the GAGs chondroitin sulfate (CS) and hyaluronic acid (HA) as gene delivery systems. For this purpose, we describe the design and evaluation of these nanosystems loaded with plasmid DNA, including an evaluation of their physicochemical characteristics, stability properties, ability to protect and efficiently transfect cells with Enhanced Green Fluorescent Protein plasmid (pEGFP) in vitro, and biocompatibility both in vitro and in vivo. We confirm that molecules with high biological value and targeting potential, such as HA and CS, can be successfully incorporated into our recently developed Sorbitan Ester-based nanoparticles (SENS) and that this incorporation leads to effective stabilisation of both nanosystems as well as protects plasmid DNA. We demonstrated that the aforementioned incorporation of HA and CS enables long-term stability of the nanosystems in both liquid and lyophilised states, which is a remarkable property that can aid in their transfer to industry. The ability of these functionalised nanosystems to transfect the A549 cell line without compromising cell viability was also shown, as well as their innocuous safety profile in vivo. Thus, we provide valuable evidence of the suitable properties and potential of these hybrid nanoparticles as gene delivery systems.
Jesus Alvareztrabado - One of the best experts on this subject based on the ideXlab platform.
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Sorbitan Ester nanoparticles sens as a novel topical ocular drug delivery system design optimization and in vitro ex vivo evaluation
International Journal of Pharmaceutics, 2018Co-Authors: Antonio Lopezgarcia, Jesus Alvareztrabado, Manuel Martinpastor, Yolanda Diebold, Alejandro SánchezAbstract:Abstract We explored the potential of two types of Sorbitan Ester nanoparticles (SENS) as novel tools for topical ocular drug delivery. The optimized SENS formulation (SENS-OPT) consisted of nanoparticles (NPs) of 170.5 nm, zeta potential +33.9 mV, and cyclosporine loading of 19.66%. After hyaluronic acid (HA) coating, the resulting SENS-OPT-HA NPs had a particle size of 177.6 nm and zeta potential of −20.6 mV. The NPs were stable during 3 months of storage at different temperatures and did not aggregate in the presence of protein-enriched simulated lacrimal fluid. There was no toxicity to cultured human corneal epithelial (HCE) cells when exposed to NPs up to 0.4% (w/v). Both NPs were effectively internalized by HCE cells through active mechanisms. Endocytosis of SENS-OPT NPs was caveolin-dependent whereas SENS-OPT-HA NP endocytosis was mediated by HA receptors. HA-receptor–mediated endocytosis may be responsible for the higher cellular uptake of SENS-OPT-HA NPs. After cyclosporine incorporation into the NPs, corneal penetration of this immunosuppressive drug by loaded SENS-OPT NPs was 1.3-fold higher than the commercial reference formulation Sandimmun®. For cyclosporine-loaded SENS-OPT-HA NPs, the penetration was 2.1-fold higher than for Sandimmun®. In ex vivo stimulated lymphocytes, both formulations demonstrated the same reduction in IL-2 levels as Sandimmun®.
Yolanda Diebold - One of the best experts on this subject based on the ideXlab platform.
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Sorbitan Ester nanoparticles sens as a novel topical ocular drug delivery system design optimization and in vitro ex vivo evaluation
International Journal of Pharmaceutics, 2018Co-Authors: Antonio Lopezgarcia, Jesus Alvareztrabado, Manuel Martinpastor, Yolanda Diebold, Alejandro SánchezAbstract:Abstract We explored the potential of two types of Sorbitan Ester nanoparticles (SENS) as novel tools for topical ocular drug delivery. The optimized SENS formulation (SENS-OPT) consisted of nanoparticles (NPs) of 170.5 nm, zeta potential +33.9 mV, and cyclosporine loading of 19.66%. After hyaluronic acid (HA) coating, the resulting SENS-OPT-HA NPs had a particle size of 177.6 nm and zeta potential of −20.6 mV. The NPs were stable during 3 months of storage at different temperatures and did not aggregate in the presence of protein-enriched simulated lacrimal fluid. There was no toxicity to cultured human corneal epithelial (HCE) cells when exposed to NPs up to 0.4% (w/v). Both NPs were effectively internalized by HCE cells through active mechanisms. Endocytosis of SENS-OPT NPs was caveolin-dependent whereas SENS-OPT-HA NP endocytosis was mediated by HA receptors. HA-receptor–mediated endocytosis may be responsible for the higher cellular uptake of SENS-OPT-HA NPs. After cyclosporine incorporation into the NPs, corneal penetration of this immunosuppressive drug by loaded SENS-OPT NPs was 1.3-fold higher than the commercial reference formulation Sandimmun®. For cyclosporine-loaded SENS-OPT-HA NPs, the penetration was 2.1-fold higher than for Sandimmun®. In ex vivo stimulated lymphocytes, both formulations demonstrated the same reduction in IL-2 levels as Sandimmun®.
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Sorbitan Ester nanoparticles (SENS) as a novel topical ocular drug delivery system: Design, optimization, and in vitro/ex vivo evaluation
International Journal of Pharmaceutics, 2018Co-Authors: Jesus Alvarez-trabado, Yolanda Diebold, Antonio López-garcía, Manuel Martín-pastor, Alejandro SánchezAbstract:Abstract We explored the potential of two types of Sorbitan Ester nanoparticles (SENS) as novel tools for topical ocular drug delivery. The optimized SENS formulation (SENS-OPT) consisted of nanoparticles (NPs) of 170.5 nm, zeta potential +33.9 mV, and cyclosporine loading of 19.66%. After hyaluronic acid (HA) coating, the resulting SENS-OPT-HA NPs had a particle size of 177.6 nm and zeta potential of −20.6 mV. The NPs were stable during 3 months of storage at different temperatures and did not aggregate in the presence of protein-enriched simulated lacrimal fluid. There was no toxicity to cultured human corneal epithelial (HCE) cells when exposed to NPs up to 0.4% (w/v). Both NPs were effectively internalized by HCE cells through active mechanisms. Endocytosis of SENS-OPT NPs was caveolin-dependent whereas SENS-OPT-HA NP endocytosis was mediated by HA receptors. HA-receptor–mediated endocytosis may be responsible for the higher cellular uptake of SENS-OPT-HA NPs. After cyclosporine incorporation into the NPs, corneal penetration of this immunosuppressive drug by loaded SENS-OPT NPs was 1.3-fold higher than the commercial reference formulation Sandimmun®. For cyclosporine-loaded SENS-OPT-HA NPs, the penetration was 2.1-fold higher than for Sandimmun®. In ex vivo stimulated lymphocytes, both formulations demonstrated the same reduction in IL-2 levels as Sandimmun®.
Gillian M Greenway - One of the best experts on this subject based on the ideXlab platform.
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supercritical fluid extraction for the analysis of liquid poly alkylene glycol lubricants and Sorbitan Ester formulations
Analyst, 1993Co-Authors: Terence P Hunt, Chris J Dowle, Gillian M GreenwayAbstract:Additives were selectively extracted from poly(alkylene glycol)(PAG) lubricant formulations using supercritical fluid extraction. The PAG matrix was adsorbed onto silica for the extractions and the extracted analytes were passed through a silica column positioned in-line in the supercritical fluid stream. The selectivity obtained by this method was compared with that obtained by the direct extraction of adsorbed and unadsorbed PAG and by the extraction of unadsorbed PAG through the in-line column. The final procedure was found to be successful in separating additives from all but the lowest molecular mass PAG oligomers. Further use of this procedure was demonstrated by a stepwise extraction of a Sorbitan Ester formulation. This gave a chemical-class fractionation of the product and so provided a sample preparation technique for further spectroscopic analysis.
William A. Goddard - One of the best experts on this subject based on the ideXlab platform.
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Experimental Study of Surfactant Retention on Kaolinite Clay
Tenside Surfactants Detergents, 2011Co-Authors: Yongfu Wu, Patrick Shuler, Stefan Iglauer, Y. Tang, William A. GoddardAbstract:We measured equilibrium surfactant retention on kaolinite clay for a large array of surfactants. We demonstrate that the mass balance measurements we used are a rapid way to screen surfactants in terms of their potential to be used in enhanced oil recovery applications. Surfactant classes investigated include: alkyl(aryl) sulfonates, ethylene oxide-propylene oxide copolymers, ethoxylated alkylphenols, alkyl polyglucosides, Sorbitan Ester ethoxylates, alkyl alcohol propoxylated sulfate sodium salts, gemini surfactants, sulfosuccinates and organo silicone-ethylene oxide-propylene oxide terpolymers. We identified several surfactants which had zero retention under the test conditions and which may therefore be suitable as enhanced oil recovery chemicals in surfactant flooding schemes. We discuss surfactant retention mechanisms on kaolinite clay and analyze surfactant structure-retention relationships for several surfactant classes.
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alkyl polyglycoside Sorbitan Ester formulations for improved oil recovery
Tenside Surfactants Detergents, 2010Co-Authors: Yongfu Wu, Patrick Shuler, Stefan Iglauer, Y. Tang, William A. GoddardAbstract:We measured interfacial tensions (IFT) of aqueous alkyl polyglucoside (APG) systems formulated with Sorbitan Ester-type cosurfactants against n-octane. The study focused on low to ultra-low IFT systems which are relevant for enhanced oil recovery (EOR). In addition, we measured equilibrium adsorption concentrations of these surfactants and cosurfactants onto kaolinite clay, commonly found in oil reservoirs. We present one surfactant EOR laboratory flood experiment with one selected APG-Sorbitan Ester formulation with which we recovered 94% of initial oil in place (IOIP).
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Alkyl polyglycoside-Sorbitan Ester formulations for improved oil recovery
Tenside Surfactants Detergents, 2010Co-Authors: Stefan Iglauer, Patrick Shuler, Y. Tang, William A. GoddardAbstract:We measured interfacial tensions (IFT) of aqueous alkyl polyglucoside (APG) systems formulated with Sorbitan Ester-type cosurfactants against n-octane. The study focused on low to ultra-low IFT systems which are relevant for enhanced oil recovery (EOR). In addition, we measured equilibrium adsorption concentrations of these surfactants and cosurfactants onto kaolinite clay, commonly found in oil reservoirs. We present one surfactant EOR laboratory flood experiment with one selected APG-Sorbitan Ester formulation with which we recovered 94% of initial oil in place (IOIP). © Carl Hanser Publisher, Munich.