Development of new pharmaceutical forms for oral administration followed by microbial study

Abstract

This study aimed to develop and evaluate amoxicillin-loaded tablets using ethylcellulose (EC) and hydroxypropyl methylcellulose (HPMC) as matrix polymers. Three formulations were prepared: T1 and T2 using EC with different AMX ratios, and T3 combining EC, HPMC, and AMX. Characterization by FTIR and XRD confirmed the presence and dispersion of AMX in the polymer matrices. Drug release studies in acidic (pH 1.2) and basic (pH 7.4) media showed higher release in acidic conditions for all formulations, especially T1 and T2, making them suitable for stomach-targeted delivery. T3, containing HPMC, showed slower and more controlled release due to its gel-forming properties. Liquid absorption tests showed T3 absorbed significantly more water due to HPMC’s hydrophilic nature, contributing to sustained drug release. Antibacterial tests demonstrated that the release behavior directly influenced antimicrobial activity. Faster release in acidic conditions led to earlier and stronger bacterial inhibition, particularly in T2. These results validate the pH-sensitive design and highlight the potential of these formulations for targeted, effective drug delivery in gastric environments.