Formulation of enteric coated microspheres containing pantoprazole

Pantoprazole is a first-line proton pump inhibitor drug for the treatment of gastric acid secretion disorders that is known to have minimal side effects and drug interactions. To improve its stability in gastric acid, delayed-release microspheres containing pantoprazole was prepared by emulsification-solvent evaporation using a polymer-containing mixture of hydroxypropyl cellulose (HPC) and ethyl cellulose (EC), which was then coated by alginate and EudragitL100. The morphological characteristics of the microspheres were examined by SEM, the particle size distribution inferred by laser diffraction, and the physical state of drug substance was measured by Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and in vitro drug release. The three formulations of microspheres chosen for this study had an average size of 100 μm. The dissolution profile showed less than 10% of the drug was released after 120 min in 0.1-M HCl and more than 75% of drug was released after 45 min in a phosphate buffer with a pH of 6.8.