Microagujas y Transcutol® como promotores de la penetración transdérmica de sibutramina formulada en parche transdérmico / Microneedles and Transcutol® as transdermal penetration enhancers of sibutramine formulated in a transdermal patch

Introducción: la principal barrera de permeación que tenemos es la piel. A pesar de ser una barrera casi impermeable para la mayoría de sustancias, se han buscado maneras para mejorar su permeabilidad utilizando nuevas tecnologías como es el uso de microagujas o promotores químicos como el Transcutol®. Objetivo: desarrollar y caracterizar un parche transdérmico a base de clorhidrato de sibutramina como fármaco modelo, usando Transcutol® y microagujas como agentes promotores de la penetración transdérmica. Métodos: se realizó la caracterización fisicoquímica de los parches mediante estudios de microscopia con luz polarizada, estudios de bioadhesión y resistencia a la ruptura. Los estudios de difusión se efectuaron en celdas de difusión verticales tipo Franz, utilizando piel abdominal humana como membrana entre ambos compartimentos. La cuantificación del principio activo se realizó mediante electroforesis capilar. Resultados: se obtuvieron parches bioadhesivos, con una adecuada estabilidad del activo en la matriz polimérica de quitosán al no precipitarse. El uso de Transcutol® y microagujas incrementó el paso de clorhidrato de sibutramina a través de piel humana con respecto al parche control. Se obtuvieron valores de flujo de 0,0649 mg.cm-2.h-1 y 0,0816 mg.cm-2.h-1 en el parche con agente promotor y microagujas de 1 y 2 mm respectivamente, en comparación con los valores de flujo de 0,0527 mg.cm-2.h-1 y 0,0554 mg.cm-2.h-1 para el parche sin agente promotor (control) utilizando microagujas de 1 y 2 mm respectivamente. Conclusiones: los resultados ponen de manifiesto la posibilidad de usar Transcutol® y microagujas para incrementar el paso de fármacos potentes y con estructura similar a la sibutramina por vía transdérmica, lo que genera de esta manera nuevas alternativas a las formas farmacéuticas orales para el tratamiento de padecimientos y enfermedades(AU)

Introduction: the main permeation barrier is the skin. Although it is almost an impermeable barrier to most substances, new ways have been examined to improve its permeability by using new technologies such as microneedles and chemical enhancers like Transcutol®. Objective: to develop and to characterize a transdermal patch containing sibutramine hydrochloride as model drug and using microneedles and Transcutol® as transdermal drug delivery enhancers. Methods: Physicochemical characterization of sibutramine hydrochloride patches using polarized light microscopy, bioadhesion, tensile strength studies. The diffusion studies were performed in Franz-type diffusion cells with human abdominal skin as a sort of membrane between both compartments. The active ingredient was quantified through capillary electrophoresis. Results: bioadhesive patches were obtained, with adequate stability of sibutramine hydrochloride in the polymer matrix of chitosan. The use of microneedles and Transcutol® increased sibutramine hydrochloride delivery through the human skin when compared with the control patch. The flow rates were 0.0649 mg.cm-2.h-1 and 0,0816 mg.cm-2.h-1 in the enhanced patch by using 1 and 2 mm microneedles respectively, in comparison with flow rates of 0,0527 mg.cm-2.h-1 and 0.0554 mg.cm-2.h-1 for the control patch having no enhancing agent with 1 and 2 mm microneedles respectively. Conclusions: the results show that it is possible to use Transcutol® and microneedles to increase the delivery of potent drugs having a structure similar to that of sibutramine through transdermal administration. All this generates new alternatives to oral pharmaceuticals in order to treat ailments and diseases(AU)

Comparison of electret and chemical enhancers in enhancing transdermal delivery of meloxicam / 第二军医大学学报

Objective: To compare the effects of electret and chemical enhancers in enhancing the transdermal delivery of meloxicam. Methods: The study was divided into 4 groups, including meloxicam patch group (control), chemical enhancer + meloxicam patch group, electret meloxicam patch, and electret + chemical enhancer + meloxicam patch group. The in vitro skin permeation of meloxicam from patches was examined by using a modified Franz diffusion cell. Ultraviolet spectrophotometry (362 nm) was used to analyze the drug concentration in the receptor. The 10 h-cumulated permeation amount of meloxicam from patchs was calculated in 3 experimental groups and were compared with that the control group. The enhancing abilities of electret and chemical enhancers were compared and the synergistic effect of them was assessed. Results: (1) 1%, 3% and 5% azones showed 1.20, 1.33, and 1.26 fold-increases in the 10 h-cumulated permeation of meloxiam respectively as compared with control group(P<0.05). (2) Most of the chemical enhancers used in this study(1%, 3% and 5% azones, 10% ethyl oleate, 1% menthnol,and 30% sulphoxiade),except for 20% propylene glycol,had enhancing effect on transdermal delivery of melocicam. Ethyl oleate(10%) was proven to be the most potent enhancer,showing a 1.86-fold cumulated permeation that of the control group(P<0.05); (3) Electret was more potent than the chemical enhancers in promoting meloxicam transdermal delivery, showing a 2.16-fold cumulated permeation that of control group (P<0.05); (4) Electret improved the enhancing effect of chemical enhancers in this study. The cumulated permeation of meloxicam in electret + chemical enhancer + meloxicam patch group was 1.14-2.82 folds that of the chemical enhancer + meloxicam patch group(P<0.05). Conclusion: Electret has a good promoting effect for transdermal drug delivery and can be used as a novel enhancer in transdermal delivery of drugs.