Preparation of Sterculia foetida-pullulan-Based Semi-interpenetrating Polymer Network Gastroretentive Microspheres of Amoxicillin Trihydrate and Optimization by Response Surface Methodology

Abstract

In this study, a novel Sterculia foetida and pullulan-based semi-interpenetrating polymer network gastroretentive microsphere formulation was prepared using the emulsion crosslinking method and optimized by central composite design. The effects of the amounts of glutaraldehyde, S. foetida, and pullulan on the percent drug entrapment efficiency (EE), percent mucoadhesion at 12 h, and percent in vitro drug release at 12 h were optimized. The microspheres were characterized using scanning electron microscopy, fourier transform infrared spectroscopy, and differential scanning calorimetry. The formulation containing 4% v/v glutaraldehyde, 8.28% w/v pullulan, and 2.14% w/v S. foetida had 88.75±1.18% EE, 80.43±1.2% drug release at 12 h, and 81.73±1.50% mucoadhesion at 12 h, which was considered optimum and was used in an in vivo radiographic study. Semi-interpenetrating polymer network microspheres loaded with amoxicillin trihydrate were successfully prepared using S. foetida and pullulan. The prolonged retention of microspheres in the stomach with sustained drug release could effectively act against Helicobacter pylori reservoirs in the stomach and improve the therapeutic effect of amoxicillin trihydrate against H. pylori.