The present research effort was aimed to develop colon targeted drug delivery system(CTDDS)of rhubarb,herbal drug using a mixed film of pectin and ethyl cellulose(EC).Pectin and ethyl cellulose were mixed in various p...The present research effort was aimed to develop colon targeted drug delivery system(CTDDS)of rhubarb,herbal drug using a mixed film of pectin and ethyl cellulose(EC).Pectin and ethyl cellulose were mixed in various proportions to coat the core tablet to target colon.The methanolic extract of rhubarb was used and the dose of the extract in each formulation was finalized by estimating the emodin content in it by high performace thin layer chromatography(HPTLC).In vitro drug release,erosion study in presence and absence of pectinase enzyme and release constant(K)of zero order was measured for each formulation.The formulation was optimized by using 32full factorial design.Formulation having 50%pectin as a coating polymer with12%coat weight was selected as an optimized formulation(OF)on the basis of%similarity with maximum desirability but this formulation was not able to retard the release of drug in stomach and upper intestine fully.So it was further coated with Eudragit S100(ES)(3%coat weight).The optimized formulation,coated with ES indicated significant laxative activity on loperamide induced constipation in rats.The results revealed that CTDDS of rhubarb using two combined approaches of biodegrable microflora-activated system and pH-sensitive system exhibited a promising colon targeting performance.展开更多
文摘The present research effort was aimed to develop colon targeted drug delivery system(CTDDS)of rhubarb,herbal drug using a mixed film of pectin and ethyl cellulose(EC).Pectin and ethyl cellulose were mixed in various proportions to coat the core tablet to target colon.The methanolic extract of rhubarb was used and the dose of the extract in each formulation was finalized by estimating the emodin content in it by high performace thin layer chromatography(HPTLC).In vitro drug release,erosion study in presence and absence of pectinase enzyme and release constant(K)of zero order was measured for each formulation.The formulation was optimized by using 32full factorial design.Formulation having 50%pectin as a coating polymer with12%coat weight was selected as an optimized formulation(OF)on the basis of%similarity with maximum desirability but this formulation was not able to retard the release of drug in stomach and upper intestine fully.So it was further coated with Eudragit S100(ES)(3%coat weight).The optimized formulation,coated with ES indicated significant laxative activity on loperamide induced constipation in rats.The results revealed that CTDDS of rhubarb using two combined approaches of biodegrable microflora-activated system and pH-sensitive system exhibited a promising colon targeting performance.
