Synthesis and characterization of starch-g-polyacrylamide-co-polylactic acid hydrogel for the potential wound dressing application

A starch-based hydrogel was synthesised by direct grafting of polylactic acid (PLA) and acrylamide onto starch. Potassium persulphate (K ₂ S ₂ O ₈ ) was used as an initiator and citric acid (CA) was used as an eco-friendly cross-linker. The purpose of the graft was to test an alternative anti-microbial wound dressing material. The FTIR, XRD, SEM and EDX data confirmed that the copolymerisation and cross-linking of the hydrogel was successful. Tests, with chemical reactions; yielded TGA data, which confirmed the enhanced thermal and mechanical properties of the augmented hydrogel. The hydrogel swelled up to 481% at pH 7.20 and exhibited a water vapour transmission rate of 148 g/m ² per day. The hydrogel also showed anti-microbial activity against both gram-positive ( S. aureus) and gram-negative ( E. coli) bacteria. Its zone of inhibition was 21 mm and 19 mm with a mild anti-oxidant property. This synthesised hydrogel is completely non-toxic and bio-degradable, making it especially suitable as a wound dressing material.