Silver-loaded poly(2-isopropenyl-2-oxazoline) based hydrogel for water disinfection with supplementary dye adsorption...

Poly(2-isopropenyl-2-oxazoline) hydrogels (PiPOx) obtained by crosslinking with HOOC-PEG-COOH and ethylenediaminetetraacetic acid diamonium salt (NH₄-EDTA) were evaluated alongside their silver-loaded counterparts (PiPOx-Ag hydrogels) for antibacterial and dye adsorption performance in aqueous environments. Incorporation of Ag⁺ ions imparted broad-spectrum antimicrobial activity, leading to a reduction in bacterial counts of Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecium, Salmonella enterica serovar Typhimurium, and Staphylococcus aureus by 4.5-6 logarithmic units per 1 mL, as well as Klebsiella pneumoniae by 2.2 logarithmic units per 1 mL after 24 h in a time-kill assay under conditions simulating contaminated water systems. The antibacterial effect of PiPOx-Ag hydrogelswas attributed to the rapid release of Ag⁺ ions from the hydrogel network and their subsequent chemisorption onto bacterial cells, indicating that PiPOx acts as an efficient Ag⁺ delivery matrix in aqueous environments. To check the potential of PiPOx-Ag hydrogelsin water decolorizaton, the adsorption of selected dyes, including azo (methyl orange), thiazine (methylene blue), triphenylmethane (malachite green), and phenolic dyes (phenol red), was evaluated. The results revealed dye-dependent uptake, with maximum removal efficiencies of 12-15% at an initial dye concentration of 10 mg/L. PiPOx exhibited intrinsic adsorption capacity, which was further enhanced upon Ag⁺ incorporation. Overall, PiPOx-based hydrogels combine effective antimicrobial activity with measurable adsorption of selected dyes, indicating their potential as multifunctional materials for integrated water treatment applications.