| Abstract: | In the present work, new matrix bead formulations based on linear and branched polysaccharides have been developed using an ionic gelation technique, and their potential use as oral drug carriers has been evaluated. Using calcium chloride as a cross‐linking agent and sodium diclofenac (SD), as a model drug, acacia gum–calcium alginate matrix beads were formulated. The response surface methodology based on 32 factorial design was used as a statistical method to evaluate and optimize the effects of the biopolymers‐blend ratio and the concentration of calcium chloride on the particle size (mm), density (g/cm3), drug encapsulation efficiency (%), and the cumulative drug release after 8 hours (R8h,%). The optimized beads with the highest drug encapsulation efficiency were examined for a drug‐excipients compatibility by powder X‐ray diffraction, differential scanning calorimetry, thermo‐gravimetric analysis, and Fourier transform‐infrared spectroscopy analyses. The swelling and degradation of the matrix beads were found to be influenced by the pH of medium. Higher degrees of swelling were observed in intestinal pH than in stomach pH. Accordingly, the drug release study showed that the amount of SD released from the acacia gum–calcium alginate beads was higher in intestinal pH than in stomach pH. Therefore, the in vitro drug release from the SD‐loaded beads appears to follow the controlled‐release (Hixson‐Crowell) pattern involving a case‐2 transport mechanism operated by swelling and relaxation of the polymeric blend matrix. |
