Silver Nanoparticles Loaded Poly(methyl methacrylate-acrylic acid) Grafted Alginate Nanocomposite Hydrogels as Efficient Catalyst and Antimicrobial Agent
摘要
Poly(methyl methacrylate-acrylic acid)-alginate [P(MMA-AA)-AG] hydrogel was synthesized by free radical precipitation polymerization while fabricated with silver nanoparticles (AgNPs) to design Ag-P(MMA-AA)-AG] hybrid hydrogels via in-situ reduction, using AgNO3 as precursor salt. The UV–Vis spectra of the freshly prepared Ag-P(MMA-AA)-AG hybrid hydrogel exhibited a stable surface plasmon resonance band at 440 nm. No measurable variation in peak position or absorbance intensity was observed with passage of time that indicating good colloidal stability of hybrid hydrogel. Catalytic activity of the hybrid hydrogel was investigated by performing the reduction of p-nitrophenol (p-NP), Congo red (CR), and Rhodamine B (RhB), as probe reactions. The reduction processes were completed within 7 min for p-NP and CR and 11 min for RhB. The estimated kapp were 0.471 min⁻¹ for p-NP, 0.485 min⁻¹ for CR, and 0.202 min⁻¹ for RhB while the values of intrinsic rate constant (kint) were found as 0.084, 0.087, and 0.036 mL.µg− 1.min− 1, respectively in presence of 5.6 µg/mL hybrid hydrogel catalyst. With an increase in the amount of hybrid hydrogel catalyst from 1.4 to 5.6 µg/mL, kₐₚₚ increased from 0.163 to 0.471 min⁻¹, while kint decreased from 0.116 to 0.084 mL.µg⁻¹.min⁻¹, respectively. Recyclability of Ag-P(MMA-AA)-AG catalyst was achieved through centrifugation and reused for the reduction of p-NP up to three reusability cycles. For 4th cycle, the catalyst showed negligible percentage reduction value as compared to first three cycles. Ag-P(MMA-AA)-AG hybrid hydrogel showed antimicrobial potential against a variety of bacterial strains with prominent zone of inhibition observed against Bacillus subtilis (+ V) and Acinetobacter baumannii (-V).
Graphical Abstract