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1.
Curr Drug Deliv ; 15(6): 795-817, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29336262

RESUMEN

BACKGROUND: In the study of lipid vesicular carriers in permeation enhancement of drug molecules across skin after the success story of liposomes, ethosomes are a recent addition. There are a number of published reviews but still, there is a lack of reviews representing various aspects in a systematic way with a detailed description of current research works. This review serves to fill this deficiency along with special emphasize on its preparation methods and applications. METHODS: Information was collected from previously published literatures which were represented after analysis in terms of various aspects such as principles, composition, preparation, mechanism of penetration, modified forms, characterization, marketed preparations and its applications. RESULT: This review is represented in an informative and easily understandable way. Basic principles and background were covered in the introduction section. Composition section contains the basic components of formulations along with the impact of various parameters on the characterization of the ethosome. A detailed discussion of all the methods along with their own utility is elaborately provided. Various aspects of characterization studies of ethosomes are also discussed. Therapeutic and cosmetic applications of ethosomes are also outlined here. CONCLUSION: In spite of having a excellent permeation-enhancing and targeted drug release profile, ethosome suffers from limited commercialization. Various challenges regarding their commercialization and product development are also discussed in this review with an objective of acting as a directional route for the researchers.


Asunto(s)
Lípidos/química , Animales , Portadores de Fármacos/química , Humanos , Liposomas/química
2.
Mater Sci Eng C Mater Biol Appl ; 69: 598-608, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27612752

RESUMEN

In the present investigation, simplex lattice mixture design was applied for formulation development and optimization of a controlled release dosage form of ketoprofen microspheres consisting polymers like ethylcellulose and Eudragit(®)RL 100; when those were formed by oil-in-oil emulsion solvent evaporation method. The investigation was carried out to observe the effects of polymer amount, stirring speed and emulsifier concentration (% w/w) on percentage yield, average particle size, drug entrapment efficiency and in vitro drug release in 8h from the microspheres. Analysis of variance (ANOVA) was used to estimate the significance of the models. Based on the desirability function approach numerical optimization was carried out. Optimized formulation (KTF-O) showed close match between actual and predicted responses with desirability factor 0.811. No adverse reaction between drug and polymers were observed on the basis of Fourier transform infrared (FTIR) spectroscopy and Differential scanning calorimetric (DSC) analysis. Scanning electron microscopy (SEM) was carried out to show discreteness of microspheres (149.2±1.25µm) and their surface conditions during pre and post dissolution operations. The drug release pattern from KTF-O was best explained by Korsmeyer-Peppas and Higuchi models. The batch of optimized microspheres were found with maximum entrapment (~90%), minimum loss (~10%) and prolonged drug release for 8h (91.25%) which may be considered as favourable criteria of controlled release dosage form.


Asunto(s)
Química Farmacéutica/métodos , Cetoprofeno/farmacología , Microesferas , Polímeros/química , Análisis de Varianza , Rastreo Diferencial de Calorimetría , Liberación de Fármacos , Cinética , Microscopía Electrónica de Rastreo , Modelos Teóricos , Tamaño de la Partícula , Reproducibilidad de los Resultados , Espectroscopía Infrarroja por Transformada de Fourier , Estadística como Asunto , Propiedades de Superficie
3.
Braz. j. pharm. sci ; 46(2): 213-218, Apr.-June 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-564887

RESUMEN

OBJECTIVES: The aim of the present investigation was to form matrix patches with ethyl cellulose (EC) as the base polymer, polyvinyl pyrrolidone (PVP) as the copolymer, plasticizer with dibutyl phthalate (DBP) or acetyl tributyl citrate (ATBC) and the drug glipizide (gz) by the solvent casting method. Physicochemical properties of the patches and in vitro drug release were determined in a modified Keshary-chien diffusion cell to optimize the patch formulations with the help of experimental data and figures for further studies. TECHNIQUES: EC and PVP of different proportions with different weight percentages of either DBP or ATBC and a fixed amount of glipizide were taken for matrix patch formations. The dried patches were used for measuring their drug contents as well as their thicknesses, tensile strengths, moisture contents and water absorption amounts in percentage. In vitro release amounts at different intervals were measured by UV-spectrophotometer. RESULTS: Drug contents varied from 96 - 99 percent. Thickness and tensile strength varied due to weight variation of the ingredients in the matrix patches. Moisture content and water absorption in wt percent were greater for the patches containing higher amount of PVP due to its hydrophilic nature. Variations in drug release were observed among various formulations. It was found that all of the releases followed diffusion controlled zero order kinetics. Two DBP patches yielded better and more adequate release. CONCLUSIONS: The two formulations with DBP were the preferred choice for making matrix patches for further studies.


O objetivo da presente pesquisa foi formar matrizes para bandagens de liberação transdérmica com etilcelulose (EC) como polímero base, polivinilpirrolidona (PVP), como copolímero, plastificante com ftalato de dibutila (DBP) ou citrato de tributilacetila (ATBC) e o fármaco glipizida (gz) pelo método de evaporação do solvente (moldagem com solvente). As propriedades físico-químicas das bandagens e a liberação do fármaco in vitro na célula de difusão de Keshary-chien modificada foram determinadas para aperfeiçoar as formulações das bandagens com o auxílio de dados experimentais e figuras para estudos posteriores. EC e PVP em diferentes proporções com porcentagens diferentes de massa tanto de DBP quanto de ATBC e quantidade fixa de glipizida foram utilizadas como matrizes para a formação de bandagens de liberação transdérmica. As bandagens secas foram empregadas para medir seus conteúdos em fármaco e, também, a sua espessura, resistência à tensão, conteúdos de umidade e porcentagem de absorção de água. As quantidades liberadas in vitro em diferentes intervalos de tempo foram medidas por espectrofotômetro de UV. Os conteúdos de fármaco variaram de 96 a 99 por cento. A espessura e a resistência à ruptura variaram devido à variação de massa dos componentes da matriz das bandagens. O conteúdo de umidade e a água absorvida, em porcentagem de massa, foram maiores para as bandagens que continham grandes quantidades de PVP devido à sua natureza hidrofílica. As variações na liberação de fármaco foram observadas entre as várias formulações. Todas as liberações seguiram a cinética de difusão controlada de ordem zero. Duas bandagens DBP resultaram em melhor e mais adequada liberação. As duas formulações com DBP foram escolhidas para a preparação de matriz de bandagens para estudos posteriores.


Asunto(s)
Sistemas de Liberación de Medicamentos , Glipizida/farmacocinética , Glipizida/química , Fenómenos Químicos , Enfermedad Crónica , Diabetes Mellitus , Enfermedades Metabólicas
4.
Environ Toxicol ; 24(4): 377-87, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18825727

RESUMEN

The effect of folic acid and folic acid + vitamin B(12) supplementation upon short-term arsenic-induced systemic and pancreatic islet cell mitochondria oxidative stress was investigated in male rats. Arsenic trioxide was administered orally at a dose of 3 mg kg body weight(-1) day(-1) for 30 days, and folic acid and vitamin B(12) were administered at a dose of 36 and 0.63 microg kg body weight(-1) day(-1), respectively, for 30 days. Compared to control, arsenic-treated group showed a significant increase in the levels of systemic oxidative markers, malondialdehyde (MDA), nitric oxide (NO), and hydroxyl radical (OH(-)) formation, which were found decreased significantly after supplementation either with folic acid or a combination of folic acid + vitamin B(12). Similar supplementations were found effective against arsenic-induced oxidative marker changes (MDA, NO, and OH(-)) in pancreatic islet cell mitochondria. Also, low activities of antioxidant defense enzymes such as superoxide dismutase and catalase, and level of antioxidant glutathione, all could regain significantly on supplementations both against systemic and islet cell mitochondria oxidative stress. Results of agarose-gel electrophoresis of DNA from lymphocytes and islet cells of arsenic-exposed rats showed DNA smearing, which could be reduced with simultaneous administration either with folic acid or a combination of folic acid + vitamin B(12). Significantly, similar supplementations were found effective in increasing the urinary clearance of arsenic. Together, these results indicate that folic acid and vitamin B(12) may be effective to reduce the arsenic-induced damage at molecular target level.


Asunto(s)
Antioxidantes/farmacología , Intoxicación por Arsénico/prevención & control , Ácido Fólico/farmacología , Óxidos/toxicidad , Vitamina B 12/farmacología , Animales , Trióxido de Arsénico , Arsenicales/metabolismo , Biomarcadores/metabolismo , Catalasa/metabolismo , Quimioprevención , Daño del ADN/efectos de los fármacos , Ácido Deshidroascórbico/análogos & derivados , Ácido Deshidroascórbico/metabolismo , Quimioterapia Combinada , Glutatión/metabolismo , Islotes Pancreáticos/metabolismo , Linfocitos/metabolismo , Masculino , Mitocondrias/efectos de los fármacos , Nitritos/metabolismo , Estrés Oxidativo/efectos de los fármacos , Óxidos/metabolismo , Ratas , Superóxido Dismutasa/metabolismo
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