TY - JOUR
T1 - Transport and retention of biogenic selenium nanoparticles in biofilm-coated quartz sand porous media and consequence for elemental mercury immobilization
AU - Wang, Xiaonan
AU - Liu, Bingshen
AU - Pan, Xiangliang
AU - Gadd, Geoffrey Michael
PY - 2019/11/20
Y1 - 2019/11/20
N2 - Bacterial biofilms are structured cell communities embedded in a matrix of extracellular polymeric substances (EPS) and a ubiquitous growth form of bacteria in the environment. A wide range of interactions between biofilms and nanoparticles have been reported. In the present study, the influence of a mixed bacterial biofilm on retention of biogenic selenium nanoparticles (BioSeNPs) and consequences for immobilization of elemental mercury (Hg0) in a porous quartz sand system were examined. BioSeNPs were significantly retained in the presence of a biofilm through electrical double layer effects, hydrogen bonding, and hydrophobic, steric and bridging interactions. Moreover, enhanced surface roughness, pore clogging, sieving and entrapment effects mediated by the biofilm also contributed to deposition of BioSeNPs. Whereas, thiol groups associated with the biofilm is a little helpful for the capture of Hg0. It is proposed that oxidative complexation between Hg0 and thiol compounds or S containing organic matter in the biofilm may result in the formation of Hg2+-thiolate complexes and HgS during the binding of Hg0 with BioSeNPs. The formation of mercury selenide was also involved in Hg0 immobilization in the porous quartz sand system.
AB - Bacterial biofilms are structured cell communities embedded in a matrix of extracellular polymeric substances (EPS) and a ubiquitous growth form of bacteria in the environment. A wide range of interactions between biofilms and nanoparticles have been reported. In the present study, the influence of a mixed bacterial biofilm on retention of biogenic selenium nanoparticles (BioSeNPs) and consequences for immobilization of elemental mercury (Hg0) in a porous quartz sand system were examined. BioSeNPs were significantly retained in the presence of a biofilm through electrical double layer effects, hydrogen bonding, and hydrophobic, steric and bridging interactions. Moreover, enhanced surface roughness, pore clogging, sieving and entrapment effects mediated by the biofilm also contributed to deposition of BioSeNPs. Whereas, thiol groups associated with the biofilm is a little helpful for the capture of Hg0. It is proposed that oxidative complexation between Hg0 and thiol compounds or S containing organic matter in the biofilm may result in the formation of Hg2+-thiolate complexes and HgS during the binding of Hg0 with BioSeNPs. The formation of mercury selenide was also involved in Hg0 immobilization in the porous quartz sand system.
KW - Biofilm
KW - Hg immobilization
KW - Mercury selenide
KW - Nanoparticle retention
KW - Selenium nanoparticles
KW - Thiols
UR - http://www.scopus.com/inward/record.url?scp=85069662985&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2019.07.309
DO - 10.1016/j.scitotenv.2019.07.309
M3 - Article
C2 - 31539943
AN - SCOPUS:85069662985
VL - 692
SP - 1116
EP - 1124
JO - Science of the Total Environment
JF - Science of the Total Environment
SN - 0048-9697
ER -