Facile fabrication and characterization of carboxymethyl cellulose hydrogel loaded with TiO2NPs as a promising disinfectant for eliminating the dissemination of waterborne pathogens through wastewater decontamination

Abstract

The purpose of this work was to develop and characterize an intriguing hydrogel called TiO₂NPs@CMC hydrogel, which is composed of carboxymethyl cellulose (CMC) loaded with titanium oxide nanoparticles (TiO₂NPs) for effective waterborne pathogen disinfection in wastewater. The TiO₂NPs were synthesized through hydrolysis and peptization. Then, incorporated into CMC matrix, and subsequently cross-linked with calcium chloride (CaCl₂). In this study, TiO₂NPs was prepared and affirmed the particle distribution with a small size using TEM. The TiO₂NPs@CMC hydrogel exhibited significant antimicrobial and antibiofilm properties against various pathogens, such as Salmonella typhi, E. coli O157, Shigella dysenteriae, Enterococcus faecalis, Bacillus cereus, and Candida albicans, with highest inhibition zone diameters 29 mm for S. typhi. The inhibitory effect demonstrated that the hydrogel significantly decreased bacterial populations at 100 μg/mL concentrations. The hydrogel demonstrated a 2.7-log reduction in microbial counts in sewage within 120 min, achieving complete inactivation of pathogens at a concentration of 2xMIC within 180 min. The biofilm inhibition rate reached 87.6 % against B. cereus. Toxicity assessments demonstrated significant biocompatibility, with no adverse effects noted in environmental applications. The findings indicate that TiO₂NPs@CMC hydrogel is a viable option for sustainable wastewater treatment, providing an efficient, safe, and environmentally friendly method for removing waterborne pathogens and preventing biofilm formation.

Keywords: Antibiofilm, water disinfection; CMC hydrogel; Titanium oxide nanoparticles, pathogenic microbes.