TY - JOUR
T1 - Prolonging the antibacterial activity of nanosilver-coated membranes through partial sulfidation
AU - Barrios, Ana C.
AU - Carrillo, Dianne
AU - Waag, Tyson R.
AU - Rice, Douglas
AU - Bi, Yuqiang
AU - Islam, Rafiqul
AU - Perreault, François
N1 - Funding Information:
This work was supported the National Science Foundation, through the Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (EEC-1449500), and the NASA STTR program (contract no. 80NSSC19C0566). We acknowledge the contribution of Naiara Mottim Justino for her assistance in the membrane performance characterization. A. B. acknowledges the support of a Dean's Fellowship from the Ira A. Fulton Schools of Engineering and a Scholar Award given by the International Chapter of the P.E.O. Sisterhood. We acknowledge the use of TEM facilities within the Eyring Materials Center at Arizona State University supported in part by NNCI-ECCS-1542160.
Funding Information:
This work was supported the National Science Foundation, through the Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (EEC-1449500), and the NASA STTR program (contract no. 80NSSC19C0566). We acknowledge the contribution of Naiara Mottim Justino for her assistance in the membrane performance characterization. A. B. acknowledges the support of a Dean's Fellowship from the Ira A. Fulton Schools of Engineering and a Scholar Award given by the International Chapter of the P.E. O. Sisterhood. We acknowledge the use of TEM facilities within the Eyring Materials Center at Arizona State University supported in part by NNCI-ECCS-1542160.
Publisher Copyright:
© The Royal Society of Chemistry 2020.
PY - 2020/9
Y1 - 2020/9
N2 - Biofouling is a major issue in membrane-based water treatment because it shortens membrane life and decreases the permeate flux. Silver, a known biocide, is often used forin situformation of silver nanoparticles (Ag NPs) on membranes for biofouling mitigation. However, Ag NPs dissolve quickly in water, limiting their effectiveness over long periods of time. This study focuses on the modification of silver-functionalized reverse osmosis (RO) membranes with different concentrations of Na2S (10−1, 10−3, and 10−5M) to identify the degree of sulfidation that limits Ag release while preserving the antibacterial effect. Sulfidized membranes decreased Ag release by >85% depending on the extent of sulfidation. Antibacterial activity was assessed usingPseudomonas aeruginosaandEscherichia coli. Results showed the highest inactivation at 73% forP. aeruginosaand 57% forE. colifor 10−5and 10−3M Na2S-treated membranes, respectively, while the more sulfidized membrane treated with 10−1M Na2S treatment had the lowest antibacterial effect. Moreover, when tested in a dynamic cross-flow RO system for 24 h, the flux declined by 24% for the Ag NPs and by 23%, 17%, and 19% as the extent of sulfidation increased. Additionally, the Ag remaining on the membrane was higher for the highest sulfidized membrane with 519 ng cm−2. Therefore, retention of the silver coating over time appears to be more important for biofilm control in RO systems than high antibacterial activity. Both 10−5M and 10−3M Na2S-treated membranes had the best balance between reduced Ag release rate and effective antibacterial and anti-biofouling performance, respectively.
AB - Biofouling is a major issue in membrane-based water treatment because it shortens membrane life and decreases the permeate flux. Silver, a known biocide, is often used forin situformation of silver nanoparticles (Ag NPs) on membranes for biofouling mitigation. However, Ag NPs dissolve quickly in water, limiting their effectiveness over long periods of time. This study focuses on the modification of silver-functionalized reverse osmosis (RO) membranes with different concentrations of Na2S (10−1, 10−3, and 10−5M) to identify the degree of sulfidation that limits Ag release while preserving the antibacterial effect. Sulfidized membranes decreased Ag release by >85% depending on the extent of sulfidation. Antibacterial activity was assessed usingPseudomonas aeruginosaandEscherichia coli. Results showed the highest inactivation at 73% forP. aeruginosaand 57% forE. colifor 10−5and 10−3M Na2S-treated membranes, respectively, while the more sulfidized membrane treated with 10−1M Na2S treatment had the lowest antibacterial effect. Moreover, when tested in a dynamic cross-flow RO system for 24 h, the flux declined by 24% for the Ag NPs and by 23%, 17%, and 19% as the extent of sulfidation increased. Additionally, the Ag remaining on the membrane was higher for the highest sulfidized membrane with 519 ng cm−2. Therefore, retention of the silver coating over time appears to be more important for biofilm control in RO systems than high antibacterial activity. Both 10−5M and 10−3M Na2S-treated membranes had the best balance between reduced Ag release rate and effective antibacterial and anti-biofouling performance, respectively.
UR - http://www.scopus.com/inward/record.url?scp=85091735841&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85091735841&partnerID=8YFLogxK
U2 - 10.1039/d0en00300j
DO - 10.1039/d0en00300j
M3 - Article
AN - SCOPUS:85091735841
SN - 2051-8153
VL - 7
SP - 2607
EP - 2617
JO - Environmental Science: Nano
JF - Environmental Science: Nano
IS - 9
ER -