Green synthesis of silver nanoparticle-embedded poly(methyl methacrylate-co-methacrylic acid) copolymer for fungal-free leathers

In this present work, we focus on the synthesis of stable silver nanoparticles (Ag NPs) by bio-reduction of Ag+ to Ag-0 using the aqueous extracts of the Nardostachys jatamansi (NJ) root. These synthesized green Ag NPs were further embedded in the copolymer poly(methyl methacrylate-co-methacrylic acid) via the emulsion copolymerization technique. The structural and optical properties of the synthesized Ag-copolymer nanocomposite have been investigated using ATR-IR, DLS and UV-Vis absorption spectroscopy techniques. In FT-IR, clearly observed axial stretching frequencies at 3449 (-N-H stretching amines), 1626 (-C=O, polyphenols), 1382 (-C-N), 1035 (-C-O) and 815 cm(-1) (aromatic) indicated the presence of functional groups (alkaloids, flavonoids, and phenolic compounds) on silver nanoparticles, which could possibly act as reducing and stabilizing agents. The SEM images of the sample showed the spherical morphology of the synthesized green Ag NPs (similar to 20-30 nm), which remained intact even after their immobilization on the copolymer matrix. Further, the wettability test using contact angle measurements revealed the hydrophobic properties of the samples, which is found to be slightly improved for Ag-copolymer nanocomposites (117.93 degrees) as compared to the bare copolymer (110.37 degrees). The antifungal activities of Ag NPs-copolymer nanocomposites were evaluated against several fungal species using the serial dilution method in different concentrations. The obtained results demonstrated that the developed Ag NPs-copolymer nanocomposite could be promising in developing the fungal-free leather materials and products. The aim of this work is to develop an antifungal-based nanocomposite for leather industries in order to get fungal-free leathers. Graphic abstract