Alginate-okra gum blend beads of diclofenac sodium from aqueous template using ZnSO4 as a cross-linker

Zinc (Zn2+)-ion induced diclofenac sodium (DS)-loaded alginate-okra (Hibiscus esculentus) gum (OG) blend beads was successfully formulated through Zn2+-ion induced ionic-gelation cross-linking method in a complete aqueous environment. Effects of polymer-blend ratio and cross-linker concentration on drug encapsulation efficiency (DEE) and cumulative drug release at 8 h (R8h) were optimized by 32-factorial design. The optimized formulation of Zn2+-ion induced DS-loaded alginate-OG beads demonstrated 89.27 ± 3.58% of DEE and 43.73 ± 2.83% of R8h. The bead sizes were within 1.10 ± 0.07 to 1.38 ± 0.14 mm. The bead surface morphology was analyzed by SEM. The drug-polymer interaction in the optimized bead matrix was analyzed by FTIR and P-XRD. These beads exhibited sustained in vitro drug release over a prolonged period of 8 h and followed controlled-release (zero-order) pattern with super case-II transport mechanism. The swelling and degradation of the optimized beads was influenced by the pH of test mediums, which might be suitable for intestinal drug delivery.