Our aim is to develop and assess microspheres loaded with olmesartan medoxomil, the antagonist of angiotensin II receptor which is used in hypertension treatment, for their efficacy. The microspheres were fabricated through a solvent evaporation process employing eudragit L100 and chitosan as the inner phase and liquid paraffin as the outer phase. Optimization was done according to the results of entrapment efficiency and in-vitro drug release. Fourier-transform infrared (FTIR) analysis indicated negligible interaction, which clarifies the suitability of the drug and excipients. The resulting microspheres exhibited a pale yellow hue and free-flowing characteristics, as confirmed by micromeritics experiments. Scanning electron microscopy (SEM) revealed smooth and spherical microspheres. Particle size, ranging from 187.44 to 358.75 μm, increased with polymer concentration, as determined by optical microscopy. Formulation F9, with a ratio of eudragit L100 to chitosan at 7:1, demonstrated the highest drug entrapment percentage (97.82%). In-vitro release studies demonstrated a reduction in olmesartan medoxomil release with increasing polymer content, with formulation F9 sustaining release for 12 hours. Furthermore, short-term accelerated stability testing indicated the physicochemical stability of the microsphere formulations throughout the stability period.
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