Preparation of gum acacia-poly(acrylamide-IPN-acrylic acid) based nanocomposite hydrogels via polymerization methods for antimicrobial applications

An interpenetrating polymer network (IPN) nanocomposite hydrogel based on gum acacia, acrylamide and acrylic acid Ga-cl-poly (AAm-IPN-AA) was synthesized by a two-step aqueous polymerization followed by a one-step impregnation of silver nanoparticles. The first step comprises the preparation of a semi-interpenetrating polymer network [Ga-cl-poly (AAm)] based on AAm and Ga via free radical polymerization. The reaction was initiated by ammonium persulphate under microwave irradiation and N, N'-methylene-bis-acrylamide was used as a crosslinker during the polymerization. The maximum percentage of swelling (1256%) was exhibited by the semi-IPN. In the second step, the synthesis of IPN was carried out by the crosslinking of polyacrylic acid onto semi-IPN hydrogel. The synthesized cross-linked hydrogels were studied by FTIR, SEM and XRD techniques. Silver nanoparticles (AgNPs) (20-80 nm) were synthesized through the reduction of silver nitrate by flower extract of Koelreuteria apiculate. The synthesized hydrogels were employed as a template for the impregnation of AgNPs. The resultant nanocomposite hydrogels were characterized by XRD, FTIR, and SEM. The prepared samples were subjected to antibacterial and antifungal studies with different bacterial (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa) and fungal strains (Aspergillus and Penicillium). Synthesized nanocomposite hydrogels have shown improved antibacterial and antifungal activities. (C) 2020 Elsevier B.V. All rights reserved.