Effects of Chloride Concentration on the Water Disinfection Performance of Silver Containing Nanocellulose-based Composites

Research output: Contribution to journalArticleScientificpeer-review

Researchers

Research units

  • Indian Institute of Technology, Madras
  • Industrial Water Ltd.
  • Betulium Ltd.

Abstract

The availability of microbially-safe drinking water is a challenge in many developing regions. Due to the well-known antibacterial effect of silver ions, materials used for their controlled release have been widely studied for point-of-use water disinfection. However, even if it is in principle known that chloride anions can suppress the antibacterial efficiency of silver, the majority of previous studies, surprisingly, have not focused on chloride concentrations relevant for freshwaters and thus for practical applications. Here, we prepared low-cost nanocellulose-aluminium oxyhydroxide nanocomposites functionalized with silver nanoparticles. Field samples obtained from Chennai, India were used as a guideline for choosing relevant chloride concentrations for the antibacterial studies, i.e., 10, 90, and 290 ppm. The antibacterial performance of the material against Escherichia coli and Bacillus subtilis was demonstrated and the influence of chloride concentration on the antibacterial effect was studied with E. coli. A 1 h contact time led to bacterial reductions of 5.6 log10, 2.9 log10, and 2.2 log10, respectively. This indicates that an increase of chloride concentration leads to a substantial reduction of antibacterial efficiency, even within chloride concentrations found in freshwaters. This work enables further insights for designing freshwater purification systems that utilize silver-releasing materials.

Details

Original languageEnglish
Article number19505
JournalScientific Reports
Volume9
Issue number1
Publication statusPublished - 1 Dec 2019
MoE publication typeA1 Journal article-refereed

ID: 40205359