Design and evaluation of pH sensitive multi-particulate systems for chronotherapeutic delivery of pioglitazone hydrochloride

Abstract

The aim of the present study was to develop a pH sensitive gastroretentive drug delivery system for an anti diabetic drug pioglitazone HCl based on gas formation technique using 3² factorial design, in order to prolong the gastric residence time and increase the overall bioavailability of the dosage form, since the absorption is erratic in diabetic patients.  The system consists of the drug loaded pellets which is coated with two different layers, inner layer of effervescent material (sodium bicarbonate) and an outermost layer of gas-entrapped sustained release polymeric membrane (Chitosan: Eudragit S100). The time to float increased as the coating level of gas-entrapped polymeric membrane increased. The optimum system could float completely within 2 min and maintained the buoyancy for a period of 12 h. Both the rapid floating and the sustained release properties were achieved in the multiparticulate drug delivery system developed in this present study.