<![CDATA[Diclofenac sodium (DS) is an effective nonsteroidal anti-inflammatory drug (NSAID) limited by a short half-life and gastric irritation. Microencapsulation with natural polymers enables gastric protection and controlled drug release. This study aims to formulate and optimize DS microcapsules using a combination of sodium alginate and chitosan polymers, with the addition of Tween 80, to achieve a gastro-resistant profile with ideal controlled release. The microcapsules were prepared using the ionotropic gelation method with varying concentrations of sodium alginate and chitosan: F1 (1.0%:0.05%), F2 (2.0%:0.1%), and F3 (3.0%:0.15%). Characterization included particle size analysis using a polarizing microscope, morphology using Scanning Electron Microscopy (SEM), entrapment efficiency (EE), and in vitro dissolution testing at various pH levels (1.2, 4.5, and 7.4). Data were analyzed using one-way ANOVA followed by Tukey’s post-hoc test to determine significant differences. F1 exhibited the best characteristics with a particle size of 221.42 ± 39.16 μm and the highest entrapment efficiency of 91.78%. The primary endpoint for gastro-resistance was successfully achieved by F1, showing a release of 9.71% at pH 1.2 for 120 minutes, meeting the compendial criterion of 10%. In contrast, F2 (13.17%) and F3 (17.88%) exceeded this limit with statistically significant differences (p0.05). SEM image analysis confirmed that F1 had the smoothest and most compact surface with minimal porosity compared to the other formulations. This study demonstrates that optimizing the polymer concentration in F1 successfully created a compact polyelectrolyte complex matrix, effectively improved entrapment efficiency, and provided stable gastro-resistant protection for safer DS delivery.]]>
