Acta Pharm. 57 (2007) 161-171
Original research paper
Mucuna gum microspheres for oral delivery of glibenclamide: In vitro evaluation
ANTHONY AMAECHI ATTAMA* and OBICHUKWU J. NWABUNZE
Drug Delivery Research Unit, Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka 410001 Nigeria
Accepted February 28, 2007
An investigation into the suitability of mucuna gum microspheres for oral delivery of glibenclamide is presented. Mucuna gum microspheres were formulated under different conditions of polymer concentration and crosslinking time at constant speed. The formulated microspheres were thereafter loaded with glibenclamide by the remote loading process. The microspheres were evaluated according to particle size, yield, loading efficiency and swelling. In vitro release of glibenclamide from the microspheres was studied in simulated intestinal fluid (SIF, pH 7.4). The release data was fitted into two release models to investigate the mechanism of glibenclamide release from the microspheres. All the microspheres showed good swelling characteristics in distilled water. The investigation revealed that the microspheres produced with 5% (m/V) mucuna gum with a crosslinking time of 5 h had the optimum prolonged release pattern. The microspheres produced using 10% (m/V) mucuna gum with a crosslinking time of 1 h had the highest delayed release of the incorporated drug whereas those without crosslinking had the fastest release of the incorporated active ingredient. Ritger-Peppas case I transport model appeared to have adequately described the release process as about 54% of the batches of microspheres conformed to this model. This implies that a formulation of glibenclamide-loaded mucuna gum microspheres is likely to offer a reliable means of delivering glibenclamide by the oral route.
Keywords: mucuna gum, microspheres, glibenclamide, in vitro release, oral delivery