Fabrication of polyvinyl alcohol-sodium alginate nanocomposite hydrogels reinforced with green synthesised silver nanoparticles for antimicrobial applications

Introduction

Infectious diseases caused by potent microbes, the recent Covid-19 medical crisis, and increase in antibiotic resistant pathogens are serious medical and scientific challenges. These challenges pose a huge impact on the economy and health care systems of any country. There is an urgent need to development functional materials for immediate decontamination of surfaces. In this project, we have successfully fabricated a peelable nanocomposite hydrogel based on polyvinyl alcohol (PVA), sodium alginate and silver nanoparticles (synthesized using a green method). The hydrogel film was crosslinked with glutaraldehyde and zinc acetate and exhibited good antibacterial properties.

Methods

Silver nanoparticles reinforced peelable hydrogel films and slabs comprising of PVA and sodium alginate were fabricated through in situ formation of nanoparticles using extracts of three different medicinally important plants such as Yerba mate, Hibiscus, and Matcha green tea. PVA and sodium alginate were crosslinked using glutaraldehyde (1 wt%), and zinc acetate solution, respectively. The physical and antibacterial properties of the prepared films were evaluated using established methods.

Results

The resulting hydrogels were tough, and the films were peelable and flexible. A strong surface plasmon resonance (SPR) peak around 400 nm confirmed the presence of silver nanoparticles in the hydrogel. The hydrogels exhibited considerable swelling capacity and the equilibrium water capacity was evaluated.

Conclusion and Work in-progress

A decontaminating hydrogel (in the form of slabs and films) composed of PVA and sodium alginate containing green synthesized silver nanoparticles were successfully prepared. The silver nanoparticles were prepared by ins situ chemical reduction using the extracts of medicinally important plant products. The presence of phytochemicals and silver nanoparticles had a synergistic effect on the antibacterial properties of the hydrogel. The mechanical properties of the films are currently being explored.