Functionalized Gum Acacia Hydrogels With Silver Nanoparticles for Enhanced Antimicrobial and Environmental Applications

In this study, we report the green synthesis of multifunctional nanocomposite hydrogels by incorporating silver nanoparticles (Ag NPs) into gum acacia (GA)-grafted poly(methacrylic acid) (GA-g-poly(MAA)) and poly(methacrylic acid-aniline) (GA-g-poly(MAA-ANI)) matrices using microwave irradiation. The synthesized nanocomposites' structural, morphological, and thermal properties were characterized using XRD, FTIR, FESEM, and TGA analyses, confirming the uniform dispersion of Ag NPs. The Ag NP content in the hydrogels was 0.17 wt% for GA-g-poly(MAA)/Ag and 0.11 wt% for GA-g-poly(MAA-Ag-ANI). They enhanced thermal stability up to 450°C. Antibacterial and antifungal activity tests demonstrated significant efficacy, with inhibition zones of 4 mm for Staphylococcus aureus, 3 mm for Escherichia coli, and 4 mm for Candida albicans. Minimum inhibitory concentration (MIC) values were as low as 0.5 μg/mL against C. albicans. The hydrogels achieved 92% methylene blue (MB) removal from a 50-ppm solution using 2 g of hydrogel in 390 min, with an adsorption capacity of 45 mg/g. These results highlight these biocompatible, eco-friendly nanocomposites' exceptional antimicrobial and dye adsorption capacity, presenting them as promising candidates for antimicrobial therapies and environmental remediation solutions. These results demonstrate the potential of nanocomposites for advanced wound dressings and efficient water treatment systems.