Disinfection of Tank Water Using Biogenic Silver Nanosilica as Anti-Microbial Agents in Jeddah City

Abstract

The need for clean water is becoming urgent all over the world. The risk of microbial contamination of drinking water and its growing ability under poor nutritional conditions occur frequently and existing water management systems do not efficiently eliminate these micropollutants. The major goal of this research is to analyze and test the drinking water quality at random locations in Jeddah City and to investigate the integration of polyurethane foam coated nano-silica silver nanoparticles (NSAgNPs) into the water purification system. The study was conducted in Jeddah city at random intervals during August to December 2020. Twenty-five samples (n = 25) of drinking water (tank water) were collected from different locations in Jeddah. The water samples were found contaminated with E. coli, Klebsiella pneumoniae. and the most prevalent yeast species was Candida albicans. The multi-drug resistance isolates were positively identified by PCR amplification of 16S rDNA gene fragments. The antimicrobial activity of nano-silica silver nanoparticles (NSAgNP) was analyzed and their optimal concentrations that remove potentially harmful microbes were determined. The cytotoxicity of NSAgNPs by Sulforhodamine B colorimetric (SRB) assay against breast adenocarcinoma cell line (MCF-7) showed no cytotoxic effect at concentrations ≤100 µg/mL. The 50% growth inhibition concentration (IC 50) of NSAgNPs after 72 h was 35.8 µg/mL. The excellent performance of NSAgNPs can be attributed to the capping surface functional groups and smaller particle size 8.931 nm, as verified by TEM. In conclusion, the purified water obtained by using 100 mg/L NSAgNPs is free from microbial contaminants and completely safe to drink. We recommend the integration of biosynthesized foam coated silver nanoparticles with water purification system to achieve the desired final water quality.