NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Effects of chlorine and other water quality parameters on the release of silver nanoparticles from a ceramic surface
Published
Author(s)
Michael W. Stewart, Angela Bielefeldt, Elisabeth Mansfield, R. Scott Summers, Joseph N. Ryan
Abstract
A quartz crystal microbalance was used to determine the effects of different water quality parameters on the desorption of silver nanoparticles from surfaces representative of ceramic water filters (CWFs). Silver nanoparticles stabilized with 25-30% casein were used in the experiments. The average hydrodynamic diameter of the nanoparticles ranged from 20 to 100 nm over pH 6.5 to 10.5. The isoelectric point was ca. 3.5 and the zeta potential was -45 mV from pH 4.5 to 9.5. The silver nanoparticles were adsorbed onto silica surfaces and then a quartz crystal microbalance was used to monitor silver release from the surface. At environmentally relevant ranges of pH (4.8 to 9.3), ionic strength (0 and 150 mM NaNO3 or 150 mM Ca(NO3)2), and turbidity (0 and 51.5 NTU kaolin clay), the rates of silver release were very similar. A high concentration of organics and bacteria (E. coli in 10% tryptic soy broth) caused rapid silver release. Water containing sodium hypochlorite removed 85% of the silver from the silica surface within 3 hours. The results suggest that contact between CWFs and prechlorinated water or bleach should be avoided.
Stewart, M.
, Bielefeldt, A.
, Mansfield, E.
, Summers, R.
and Ryan, J.
(2012),
Effects of chlorine and other water quality parameters on the release of silver nanoparticles from a ceramic surface, Water Research
(Accessed October 14, 2025)