Development of calcium pectinate-tamarind seed polysaccharide mucoadhesive beads containing metformin HCl

Novel mucoadhesive beads containing metformin HCl made of low methoxy (LM) pectin-tamarind seed polysaccharide (TSP) polymer-blend was developed through ionotropic-gelation technique and optimized using 3(2) factorial design. Effects of LM pectin and TSP amounts on drug encapsulation efficiency (DEE), and cumulative drug release at 10h (R-10h) were analyzed using response surface methodology. The optimized calcium pectinate-TSP beads containing metformin HCl showed DEE of 95.12 +/- 4.26%, R-101, of 46.53 +/- 3.28%, and mean diameter of 1.93 +/- 0.26 mm. The in vitro drug release from these beads was followed controlled-release (zero-order) pattern with super case-II transport mechanism. These beads were also characterized by SEM and FTIR. The optimized beads also exhibited pH-dependent swelling, good mucoadhesivity with goat intestinal mucosa and significant hypoglycemic effect in alloxan-induced diabetic rats over prolonged period after oral administration. (C) 2013 Elsevier Ltd. All rights reserved.