Development and Characterization of a Citric Acid-crosslinked Cassava Starch Hydrogel Functionalized with Aloe Vera for Potential Tissue Repair Applications

Abstract

This study presents the development and characterization of a bio-based hydrogel synthesized from cassava starch and citric acid through a green approach and functionalized with Aloe vera. The material was prepared using a two-stage thermal curing process (110 °C for 1 h followed by 140 °C for 30 min) and evaluated for physicochemical, electrical, and antibacterial properties. FTIR-ATR analysis indicated the formation of ester linkages associated with starch–citric acid crosslinking. Swelling analysis revealed limited aqueous stability, with several formulations showing mass loss rather than consistent swelling. Surface pH values ranged from 2.02 to 3.55, indicating a strongly acidic profile associated with residual citric acid. Electrical characterization showed a formulation-dependent response related to ionic transport within the hydrogel matrix. A qualitative reduction in Escherichia coli growth was observed; however, quantitative antibacterial analysis was not performed. Overall, the results demonstrate the influence of formulation composition on hydrogel behavior and highlight the need for further optimization and biological validation. Keywords ⎯ Aloe Vera, Cassava Starch, Citric Acid, Impedance Spectroscopy.