Characterization of high amylose starch-microcrystalline cellulose based floatable gel for enhanced gastrointestinal retention and drug delivery

Abstract

Floatable high amylose rice starch and microcrystalline cellulose hybrid gels were developed for gastric drug delivery purposes. The concentration of microcrystal cellulose was varied from 1 to 4% to provide the porous rigid surface with high floatability and thermal stability. The hybrid gels showed high water holding capacity (419.11–459.54%), peak force (140.39–255.32 N), and floatability (8–27 h). The high peak temperature (114.1–122.5 °C) and residual mass 17.59–33.33% confirmed the thermal stability of the hybrid gel. The in-vitro drug release and gastrointestinal digestion behavior of the gel was studied with glycyrrhizic acid as a model drug. For the increase in the microcrystalline cellulose concentration in the gel, the loading efficiency and release of glycyrrhizic acid was decreased. Moreover, the release of glycyrrhizic acid in different digestion stages varied significantly with microcrystalline cellulose concentration in the hybrid gels. A Fickian diffusion mode for the release of loaded drug was also observed. The present study manifests improved gastro-retentive drug delivery systems with rice starch and cellulose hybrid gels.

Keywords

• Rice starch
• Microcrystalline cellulose
• Thermal stability
• Drug release