FORMULATION AND CHARACTERIZATION OF HARD, GELATIN-LIKE CAPSULES BASED ON CORN STARCH, AGAR-AGAR, SODIUM ALGINATE AND HPMC FOR ORAL DELIVERY OF SMALL MOLECULES
DOI:
https://doi.org/10.53555/bnkd6h19Keywords:
Plant-based capsules, Starch-agar composite, HPMC, Sodium alginate, Capsule characterization, Oral drug deliveryAbstract
This study develops and evaluates plant-based hard capsules formulated using corn starch, agar-agar, sodium alginate, and hydroxypropyl methylcellulose (HPMC) as an alternative to traditional gelatin capsules. The polymers were optimized by adjusting viscosity, polymer ratios, and plasticizer concentration to achieve dip-coating compatibility. Physicochemical characterizations included viscosity, swelling index, moisture content, capsule wall thickness, tensile strength, and disintegration time. Structural confirmation was performed using SEM, FTIR, and DSC. The optimized formulation exhibited uniform film morphology, improved thermal stability, inter-polymer hydrogen bonding, and mechanical strength comparable to gelatin. Dissolution studies revealed rapid and reproducible drug release in simulated gastric and intestinal fluids. Compared with literature-reported gelatin, HPMC, alginate, and starch capsules, the proposed composite formulation showed balanced mechanical properties, controlled hydration, low moisture sensitivity, and faster disintegration. The study demonstrates that a synergistic blend of starch, agar, alginate, and HPMC can serve as a robust, low-cost, plant-based alternative for oral drug delivery systems.
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