RESUMEN
Biodegradable microparticles based on poly-D,L-lactide with entrapped mixture of herbal water-soluble extracts of Plantago major and Calendula officinalis were prepared. For preparation of these microparticles the previously developed method based on the usage of supercritical carbon dioxide (SC-CO2) was proposed. Microparticles were obtained by two techniques: 1) by preparing porous polymer monolith containing entrapped mixture of herbal extracts, which was then reduced to fine microparticles (ca. 0.1 mm) by dry ice grinding (called here as "monolithisation technique") and 2) by spraying of this polymer/extracts mixture through a jet (spray technique). In vitro release kinetic profile of herbal extract mixture was found to depend on the microparticle preparation technique, on the microparticle structure as well as on the initial ratio polymer/extracts (w/w). The microparticles were used for gastric ulcer treatment in a rat model. The extracts released from microparticles were found to accelerate tissue repair.
Asunto(s)
Calendula/química , Dióxido de Carbono , Extractos Vegetales/química , Plantago/química , Poliésteres/química , Animales , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/patología , Cinética , Masculino , Tamaño de la Partícula , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Ratas , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/patologíaRESUMEN
The microcapsules with entrapped herbal water-soluble extracts Plantago major and Calendula officinalis L. (HE) were prepared by LbL-adsorption of carrageenan and modificated chitosan onto CaCO3 microparticles with their subsequent dissolving after the treatment of EDTA. Entrapment of HE was performed by adsorption and co-precipitation techniques. The co-precipitation provided better entrapment of HE compared to adsorption. In vitro release kinetics in an artificial gastric juice (AGJ) was studied. The HE release was shown to accelerate gastric ulcer treatment in a rat model.