1,721,053 research outputs found
High-grade extracellular vesicles preparation by combined size-exclusion and affinity chromatography
No full textExtracellular vesicles (EVs) have recently gained growing interest for their diagnostic and therapeutic potential. Despite this, few protocols have been reported for the isolation of EVs with preserved biological function. Most EV purification methods include a precipitation step that results in aggregation of vesicles and most available techniques do not efficiently separate the various types of EVs such as exosomes and ectosomes, which are involved in distinct biological processes. For this reason, we developed a new two-step fast performance liquid chromatography (FPLC) protocol for purification of large numbers of EVs. The method comprises size exclusion chromatography followed by immobilized metal affinity chromatography, which is enabled by expression of poly-histidine tagged folate receptor α in the parental cells. Characterisation and comparison of the EVs obtained by this method to EVs purified by differential centrifugation, currently the most common method to isolate EVs, demonstrated higher purity and more selective enrichment of exosomes in EV preparations using our FPLC method, as assessed by comparison of marker proteins and density distribution. Our studies reveal new possibilities for the isolation of defined subpopulations of EVs with preserved biological function that can easily be upscaled for production of larger amounts of EVs.Open-Access-Publikationsfonds 202
Nanotechnology contributions to the pharmacotherapy of pediatric HIV: a dual scientific and ethical challenge and a still pending agenda
Full text linkThe Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS) is the most deadly infectious disease of our times. It currently affects more than 40 million people worldwide [101]. HIV is a disease of poverty as more than 80% of the patients live in developing nations and 60% in the sub-Saharan region (sSR) of Africa. Children represent approximately 6% of the infected population, though 15% of the new infections and the 15% of the nearly 2 million annual deaths. In addition, 15 million children have been orphaned due to AIDS [102]; 11.6 millions only in the sSR. Pediatric HIV has been almost eradicated in developed countries by preventing the mother-to-child-transmission (MTCT) and replacing natural delivery by caesarean. Conversely, in the developing world, 1000 new cases are registered every day. Only 10% of the HIV-positive children have appropriate access to medication, this extent decreasing dramatically to less than 2% in the sSR [103]. Thus, while HIV is gradually becoming a chronic and manageable disease in Europe and North America owing to the high activity antiretroviral therapy (HAART) or cocktail, most HIV-infected children in Africa are unfortunately sentenced to die before the two years of age.Fil: Sosnik, Alejandro Dario. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Nanomedicine in Latin America
Full text linkThis special issue of Journal of Biomaterials and Tissue Engineering includes articles from Latin American researchers that work in an emerging discipline at the interface of biomaterials science, nanotechnology and therapeutics called Nanomedicine and that comprises the use of different mono, bi and three-dimensional nano-objects (e.g., nanoplates, nanoparticles, nanotubes, etc.) to address different medical problemsFil: Abraham, Gustavo Abel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina;Fil: Romero, Eder Lilia. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Diseño de Estrategias de Targeting de Drogas; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina;Fil: Sosnik, Alejandro Dario. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina
Nanomedicine in Latin America
Full text linkThis special issue of Journal of Biomaterials and Tissue Engineering includes articles from Latin American researchers that work in an emerging discipline at the interface of biomaterials science, nanotechnology and therapeutics called Nanomedicine and that comprises the use of different mono, bi and three-dimensional nano-objects (e.g., nanoplates, nanoparticles, nanotubes, etc.) to address different medical problemsFil: Abraham, Gustavo Abel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina;Fil: Romero, Eder Lilia. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Diseño de Estrategias de Targeting de Drogas; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina;Fil: Sosnik, Alejandro Dario. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina
Novel Poly(Ethylene Oxide)-b-Poly(Propylene Oxide) Copolymer-Glucose Conjugate by the Microwave-Assisted Ring Opening of a Sugar Lactone
Full text linkIn this work, we investigated for the first time the conjugation of gluconolactone to a poly(ethylene oxide)-poly(propylene oxide) block copolymer by a microwave-assisted ring opening reaction. The glucosylated copolymer was obtained with high yield(90%). A conjugation extent of approximately 100% was achieved within 15 min. The modification reduced the critical micellar concentration and increased the size of the micelles. The agglutination of the modified polymeric micelles by a soluble lectin that binds glucose confirmed the recognizability of the modified nanocarrier. Finally, the solubilization of darunavir, an anti-HIV protease inhibitor, showed a sharp increase of the aqueous solubility from 91 microgram/mL to 14.2 and 18.9 mg/mL for 10% w/v pristine and glucosylated polymeric micelles, respectively.Fil: Glisoni, Romina Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Nanobiotecnología. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Nanobiotecnología; ArgentinaFil: Sosnik, Alejandro Dario. Technion - Israel Institute of Technology; Israel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Hidrogeles de uso farmacéutico
No full textEl objetivo de esta obra es proporcionar un texto tanto para la actualización de profesionales como para la introducción de estudiantes de Farmacia a temas que consideramos prioritarios en el campo de la ciencia y la tecnología farmacéuticas. Se han desarrollado múltiples avances en las últimas décadas, y escasean los textos de esta naturaleza en castellano. Esperamos que esta obra sea de utilidad para los alumnos de grado, posgrado y profesionales en los distintos ámbitos del ejercicio profesional de las ciencias farmacéuticas. Hemos pensado que este espacio de difusión del conocimiento de las ciencias farmacéuticas debe ser amplio y servir para agrupar a las diferentes vertientes de especialistas, tanto de la Argentina como de nivel internacional. La progresiva introducción de eficacia, seguridad y confiabilidad en su diseño y producción "atributos que se suman a los ya clásicos de identidad, pureza, potencia y estabilidad" ha enriquecido la tecnología farmacéutica con la incorporación de metodologías y conocimientos que permiten satisfacer los nuevos requerimientos. Por ello, esta publicación pone especial énfasis en dar una visión tanto de la situación actual como de la perspectiva hacia el futuro cercano en cada tema, de manera que el lector pueda adquirir un panorama de la evolución de cada uno de los tópicos.Fil: Seremeta, Katia Pamela. Universidad Nacional del Chaco Austral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Sosnik, Alejandro Dario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Technion - Israel Institute of Technology; Israe
Cyclodextrin complexes for treatment improvement in infectious diseases
Full text linkInfectious diseases are a heterogeneous group of maladies that represent a serious burden to healthcare systems worldwide. Most of the available antimicrobial drugs display poor biopharmaceutical properties that compromise their effectiveness. Cyclodextrins (CDs) are cyclic oligosaccharides of glucopyranose formed by a variable number of repeating units that combine a hydrophilic surface with a hydrophobic cavity. The production of drug/CD complexes has become one of the most extensively investigated technology approaches to improve the stability, solubility, dissolution rate and bioavailability of drugs. The present work overviews the applications of CDs for the formulation of anti-infective agents along with the most relevant administration routes. Finally, an update on the complexes with CDs available on the market to treat infectious diseases is presented.Fil: Imperiale, Julieta Celeste. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sosnik, Alejandro Dario. Technion - Israel Institute of Technology; Israel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Application of the Jouyban-Acree model for Estimating the Solubility of Naproxen in Ethanol + Water Cosolvent Mixtures
Full text linkEn este trabajo se evaluó la validez de una adaptación puntual del modelo de Jouyban-Acree (J-A) en comparación con la utilidad de la ecuación de solubilidad logarítmica-lineal propuesta por Yalkowsky y Roseman (Y-R), para la estimación de la solubilidad del naproxeno en mezclas cosolventes etanol + agua, en función de la composición cosolvente y de la temperatura, en el intervalo entre 20,0 y 40,0 °C. Los modelos de J-A y Y-R requieren únicamente de los valores experimentales de solubilidad de los fármacos en los solventes puros en función de la temperatura. Se encontró que los valores obtenidos con los dos modelos son bastante similares entre sí y que presentan algunas desviaciones notorias respecto a los valores experimentales reportados en la literatura.In this work the validity of a trained version of the Jouyban-Acree (J-A) model was evaluated to predict the solubility of naproxen in ethanol + water cosolvent mixtures. The usefulness of the solubility log-linear equation proposed by Yalkowsky and Roseman was also evaluated for the same drug in this cosolvent system. The solubility estimation was studied as a function of temperature and cosolvent composition. The J-A and Y-R models require only the experimental solubility values in the pure solvents at all the temperatures evaluated. The calculated values by using both models were similar between them but they notoriously deviated from experimental values presented in the literature.Fil: Vargas, Edgar. Universidad de los Andes; ColombiaFil: Sosnik, Alejandro Dario. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Martinez, Fleming. Universidad Nacional de Colombia; Colombi
Thermodynamics of Transfer Processes of Triclosan from Water to Some Organic Solvents with Different Hydrogen Bonding Capability
No full textThe thermodynamic functions Gibbs energy, enthalpy and entropy for the dissolution and mixing processes of triclosan (TS) in water are presented. These quantities were calculated by using the van’t Hoff and Gibbs equations from solubility values determined in the temperature range from 293.15 to 313.15 K. In addition, the corresponding thermodynamic quantities of the drug transfer processes from water to some organic solvents with different hydrogen bonding capability were also calculated. In all cases, Gibbs energy of transfer comprised negative values, indicating the preference of TS for all the organic media evaluated. Nevertheless, enthalpy and entropy of transfer assumed positive or negative values according to specific system. It was clear that hydrogen bonding plays a significant role on dissolution and transfer processes.Fil: Delgado, Daniel R.. Universidad Nacional de Colombia; ColombiaFil: Sosnik, Alejandro Dario. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Martínez, Fleming. Universidad Nacional de Colombia; Colombi
Polymer-based carriers for opthalmic drug delivery
Full text linkDespite the wide range of diseases affecting the eye, ocular bioavailability remains a challenge in ophthalmic drug delivery. Nowadays an extensive variety of polymers are being explored to develop colloidal drug carriers which show better performance than the more popular drug solutions. For instance, regardless of the type of polymer used, these systems prolong the residence time of the drug in the absorption site with respect to conventional aqueous eye drops which are rapidly cleared from eye surface. Furthermore, colloidal drug carriers can be internalized by cells. In addition, positively charged particles penetrate the cornea more effectively than neutral or negatively charged ones. These phenomena lead to higher ocular bioavailability. This review overviews the different polymers available to produce drug-loaded gels, microparticles and nanoparticles, highlighting the advantageous features and biocompatibility of each polymer and the major achievements in the field of ocular delivery. In addition, the design of more complex delivery systems that combine several delivery platforms is presented. Finally, regulatory aspects relevant to the clinical translation of advanced ophthalmic drug delivery systems are also discussed. All together, this manuscript is aimed at guiding pharmaceutical research and development towards the rationale polymer selection to produce drug delivery systems that improve the performance of drugs for the therapy of ophthalmic diseases.Fil: Imperiale, Julieta Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Investigaciones Farmacológicas; ArgentinaFil: Acosta, Gabriela Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Investigaciones Farmacológicas; ArgentinaFil: Sosnik, Alejandro Dario. Technion - Israel Institute of Technology; Israe
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