Evaluation of Adhesion and Release Kinetics of Panax Notoginseng Saponines Bioadhesive Tablets in vitro

OBJECTIVE To study the release kinetics of Panax Notoginseng Saponines(PNS) and various ginsenosides from gastrointestinal bioadhesive tablets,and to evaluate their bioadhesive force to rabbit small intestine in vitro.METHODS Using rotating basket method,the dissolubility was determined with water as dissolution medium at speed of 100 r·min~(-1).The concentrations of PNS and three ginsenosides(notoginsenoside R_1,ginsenoside Rg_1 and ginsenoside Rb_1) were determined by coloration method and HPLC method respectively.To study the release mechanism of PNS and three ginsenosides,Zero order model,first order model,Higuchi equation and Peppas equation were used to simulate the dissolution curves.Similarity factor method was used to determine whether the release curves of PNS and three ginsenosides were similar.A self-made apparatus was used to compare the adhesive force between the bioadhesive tablets and regular tablets in rabbit small intestine in vitro.RESULTS The release kinetics of PNS,notoginsenoside R_1 and ginsenoside Rb_1 in bioahesive-tablets was discribed by Peppas equation,and the release kinetics of ginsenoside Rg_1 was fitted by first order model.The bioadhesion study showed that there were obvious differences between bioadhesive tablets and regular tablets in adherering to small intestine mucosa(P0.01).CONCLUSION The release mechanism of PNS,notoginsenoside R_1,ginsenoside Rg_1 and ginsenoside Rb_1 in bioadhesive tablets are different,but their release curves are similar.The adhesive force of PNS bioadhesive tablets is stronger than that of regular tablets.