Effect of preparation conditions on morphology, drug content and release profiles of poly(hydroxybutyrate) microparticles containing piroxicam

In this study, poly(hydroxybutyrate) microparticles containing piroxicam were prepared by the oil-in-water emulsion-solvent evaporation method. The effects of some process conditions on drug content were determined using a 2³ factorial design. The piroxicam loading efficiency varied from 5.5 to 89.8 %. Hollow and irregular microparticles with drug crystals on their surfaces were obtained when 5 mL of chloroform was used as the internal phase. In the release study, all of the piroxicam was released to the dissolution medium (phosphate buffer pH 7.4) after 8 h. Small spherical microspheres with a rough and porous polymeric matrix were obtained when 20 mL of dichloromethane was used as the internal phase and isopropanol was added to the external aqueous phase. These microspheres controlled the piroxicam release for approximately 50 h. The results demonstrated that it is possible to obtain microparticles with specific characteristics by the optimization of the process conditions.No presente estudo foram preparadas micropartículas de poli(hidroxibutirato) contendo piroxicam pela técnica de emulsão-evaporação do solvente. A influência de alguns parâmetros do processo sobre a eficiência de encapsulação do fármaco foi avaliada por meio de um planejamento fatorial do tipo 2³. A eficiência de encapsulação do piroxicam variou de 5,5 a 89,8%. Micropartículas ocas e irregulares, contendo cristais de fármaco na superfície, foram obtidas quando se utilizou 5 mL de clorofórmio como fase interna da emulsão. Com o ensaio de liberação in vitro evidenciou-se que, após 8 h, todo o fármaco havia sido liberado para o meio. Micropartículas esféricas com superfície externa rugosa e porosa foram obtidas quando se utilizou 20 mL de diclorometano como fase interna e adicionou-se isopropanol à fase externa da emulsão. Essas microesferas foram capazes de controlar a liberação do piroxicam durante 50 h. Os resultados obtidos demonstraram que é possível obter micropartículas com características específicas pela otimização das condições empregadas no processo de encapsulação.91492

Development and validation of a fluorimetric method to determine curcumin in lipid and polymeric nanocapsule suspensions

A simple, rapid, and sensitive fluorimetric method was developed and validated to quantify curcumin in lipid and polymeric nanocapsule suspensions, using acetonitrile as a solvent. The excitation and emission wavelengths were set at 397 nm and 508 nm, respectively. The calibration graph was linear from 0.1 to 0.6 µg/mL with a correlation coefficient of 0.9982. The detection and quantitation limits were 0.03 and 0.10 µg/mL, respectively. The validation results confirmed that the developed method is specific, linear, accurate, and precise for its intended use. The current method was successfully applied to the evaluation of curcumin content in lipid and polymeric nanocapsule suspensions during the early stage of formulation development.Um método fluorimétrico simples, rápido e sensível foi desenvolvido e validado para quantificação da curcumina em suspensões de nanocápsulas lipídicas e poliméricas, usando acetonitrila como solvente. Os comprimentos de onda de excitação e emissão foram 397 nm e 508 nm, respectivamente. Nas condições testadas, a curva de calibração demonstrou-se linear na faixa de 0,1 a 0,6 µg/mL, exibindo coeficiente de correlação de 0,9982. Os limites de detecção e quantificação foram 0,03 e 0,10 µg/mL, respectivamente. Os resultados da validação confirmaram que o método desenvolvido é específico, linear, exato e preciso para o uso proposto. O presente método foi aplicado com sucesso para a avaliação do teor de curcumina nas suspensões de nanocápsulas lipídicas e poliméricas durante o estágio inicial do desenvolvimento da formulação

On the mucoadhesive properties of chitosan-coated polycaprolactone nanoparticles loaded with curcumin using quartz crystal microbalance with dissipation monitoring

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Poly(ethylene glycol) hydroxystearate-based nanosized emulsions: effect of surfactant concentration on their formation and ability to solubilize quercetin

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Physicochemical and morphological characterizations of glyceryl tristearate/castor oil nanocarriers prepared by the solvent diffusion method

International audienceIn this study, drug delivery nanocarriers based on glyceryl tristearate and castor oil at different ratios were prepared by the hot solvent diffusion method. PEG 660-stearate or Poloxamer 188 and soybean lecithin were used as surfactant and co-surfactant, respectively. Structural and physicochemical characteristics of the particles were investigated by means of dynamic light scattering (DLS), differential scanning calorimetry (DSC), wide-angle X-ray scattering (WAXS), atomic force microscopy (AFM) and transmission electron microscopy (TEM and cryo-TEM). DLS data indicated that smaller particles were obtained when the liquid lipid was used alone to prepare nanoemulsions (NEs). TEM and cryo-TEM images showed that NEs presented spherical particles, whereas solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) presented more complex shapes. SLNs exhibited lamellar crystal structure, while NLCs displayed a hybrid structure composed of a lamellar crystalline phase in contact with a liquid oil compartment. These experiments contribute to a better understanding of the structure and release performance of these drug carrier systems

Elaboration of chitosan-coated nanoparticles loaded with curcumin for mucoadhesive applications

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Xyloglucan-block-poly(ε-caprolactone) copolymer nanoparticles coated with chitosan as biocompatible mucoadhesive drug delivery system

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Fluorescence properties of curcumin-loaded nanoparticles for cell tracking

Bassam Felipe Mogharbel,1 Julio Cesar Francisco,1 Ana Carolina Irioda,1 Dilcele Silva Moreira Dziedzic,1 Priscila Elias Ferreira,1 Daiany de Souza,1 Carolina Maria Costa de Oliveira Souza,1 Nelson Bergonse Neto,2 Luiz Cesar Guarita-Souza,2 Celia Regina Cavichiolo Franco,3 Celso Vataru Nakamura,4 Vanessa Kaplum,4 Letícia Mazzarino,5 Elenara Lemos-Senna,6 Redouane Borsali,7 Paula A Soto,8 Patricia Setton-Avruj,8 Eltyeb Abdelwahid,9 Katherine Athayde Teixeira de Carvalho1 1Cell Therapy and Biotechnology in Regenerative Medicine Department, Pelé Pequeno Príncipe Institute, Child and Adolescent Health Research and Pequeno Príncipe Faculty, Curitiba, Paraná, Brazil; 2Institute of Biological and Health Sciences, Pontifical Catholic University of Paraná (PUCPR), Centro de Ciências Biológicas e da Saúde (CCBS), Curitiba, Brazil; 3Cell Biology Department, Federal University of Paraná, Curitiba, Paraná, Brazil; 4Department of Pharmaceutical Sciences, Universidade Estadual de Maringá, Maringá, Paraná, Brazil; 5Department of Pharmaceutical Sciences, NanoBioMat Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil; 6Department of Pharmaceutical Sciences, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil; 7Centre de Recherches sur les Macromolécules Végétales (CERMAV), Centre National de la Recherche Scientifique (CNRS), University Grenoble Alpes, F-38000, Grenoble, France; 8Instituto de Química y Físicoquímica Biológica (IQUIFIB), Departament of Química Biológica, Facultad de Farmacia y Bíoquímica, Universidad de Buenos Aires (UBA) Consejo nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentine; 9Feinberg School of Medicine, Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, Il, USA Background: Posttransplant cell tracking, via stem cell labeling, is a crucial strategy for monitoring and maximizing benefits of cell-based therapies. The structures and functionalities of polysaccharides, proteins, and lipids allow their utilization in nanotechnology systems. Materials and methods: In the present study, we analyzed the potential benefit of curcumin-loaded nanoparticles (NPC) using Vero cells (in vitro) and NPC-labeled adipose-derived mesenchymal stem cells (NPC-ADMSCs) (in vivo) in myocardial infarction and sciatic nerve crush preclinical models. Thereafter, transplantation, histological examination, real time imaging, and assessment of tissue regeneration were done. Results: Transplanted NPC-ADMSCs were clearly identified and revealed potential benefit when used in cell tracking. Conclusion: This approach may have broad applications in modeling labeled transplanted cells and in developing improved stem cell therapeutic strategies. Keywords: mesenchymal stem cells, transplantation, cell marking, myocardium infarction, sciatic nerve crus