Enhanced E. coli Capturing Efficacy Over Magnetic Dextrin–Cobalt Sulfide Nanohybrid as a Promising Water Disinfection System

Abstract

The aim of this research is synthesis of a promising bacterial elimination nanohybrid for water disinfection. Hence dextrin, a carbohydrate polymer composed of linear α-(1,4)-linked d-glucose, is used as an intermediate to prepare Fe3O4–dextrin–CoS nanohybrid. At the first step magnetic dextrin was prepared by one step ultrasound assisted route using Fe2+ as iron source and dextrin as capping agent. At the second step functional groups of dextrin was employed to trap Co2+ ions for decorating CoS at the biosorbent structure through refluxing route. The structure of the magnetic dextrin and nanohybrid was studied by XRD, EDX, FESEM, TGA and zeta potential measurement. EDX and TGA results confirmed that the CoS has been decorated with high density onto magnetite dextrin structure. The prepared nanohybrid has been employed to capture Escherichia coli as a sample pathogen from water solution. Effective parameters on bacterial elimination, i.e., pH, contact time, nanohybrid dosage and presence of anions have been studied. Results showed that at pH of 3.5, contact time of 15 min and nanohybrid dosage of 20 mg E. coli capturing efficacy was more than 99% which confirmed high efficiency of the nanosystem in bacteria elimination from water solution.