Preparation and Evaluation of Glibenclamide-loaded Microparticles Using Admixtures of Lipids and Polymer for Improved Oral Delivery

Glibenclamide (GB) is a potent Sulfonylurea used in treating type 2 diabetes mellitus belonging to Biopharmaceutics Classification System (BCS) Class II drugs. This study aimed to design, prepare, and assess glibenclamide-loaded solid microparticles (GSM) for possible improvement of solubility and oral bioavailability. GSM is formulated with a lipid matrix made of Dika wax, goat fat, and polyethylene glycol (PEG 4000) using a hot homogenization method. They were characterized for particle morphology and size, pH stability, encapsulation efficiency, in vitro release and evaluated for in vivo blood glucose-reducing activities. The morphology and particle sizes showed smooth and spherical particles in the 47.1 ± 0.84 to 66.3 ± 0.58 µm range for the eight batches. The pH of the microparticles was stable. The encapsulation efficiency (%) ranged from 32.1 ± 1.84 to 89.3 ± 0.61. In vitro release showed maximum release at 72.30% and 84. 44% for batches A2 and B2 respectively. Maximum blood glucose lowering of 87.65% and 54.24% for batch A1 and the standard drug after 24 h was observed. This study showed that these microparticles effectively improved the bioavailability of GB as shown by increased hypoglycemic activities.