Water-resistant cellulosic filter containing non-leaching antimicrobial starch for water purification and disinfection

Water-resistant cellulose foam paper was developed in this work in an attempt to improve the antimicrobial activity of cellulose foam paper for capture and deactivation of pathogenic microorganisms existed in water. Results indicated that the cellulose foam paper could significantly improve household water quality by incorporating guanidine-based polymer modified with starch or called antibacterial thermoplastic starch (ATPS) into fibre network in the presence of proper amount of fiber fines. Ring diffusion testing demonstrated that no ATPS diffused around or underneath of samples, verifying that cellulose foam filter added by ATPS were of non-leaching type. Furthermore, the viability of bacteria before and after filtering and the structure of cellulose foam paper were analyzed via fluorescence microscopy and scanning electron microscopy images. The findings further proved the effectiveness of antimicrobial cellulose foam in deactivating pathogens, E.coli in particular.