Final published version
Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Novel speciation method based on diffusive gradients in thin-films for in situ measurement of CrVI in aquatic systems
AU - Pan, Yue
AU - Guan, Dong-Xing
AU - Zhao, Di
AU - Luo, Jun
AU - Davison, William
AU - Ma, Lena Q.
PY - 2015/12/15
Y1 - 2015/12/15
N2 - Hexavalent chromium (CrVI) is much more toxic and mobile than the trivalent species (CrIII) and consequently, in situ monitoring of CrVI can improve the understanding of Cr biogeochemistry and toxicity in ecosystems. The passive diffusive gradients in thin-films (DGT) technique is a powerful tool for determining metal(loid) speciation, but a binding phase that absorbs only one specific species of Cr is needed. N-Methyl-d-glucamine (NMDG) functional resin was incorporated into the DGT binding phase for selective measurement of CrVI. This NMDG-DGT sampler exhibited a theoretically linear accumulation of CrVI, with negligible accumulation (<5%) of CrIII, even after 72 h deployment. The good prediction of CrVI concentration in synthetic freshwater with NMDG-DGT, even in the presence of 10-time more CrIII, further indicated the sampler’s reliability in selective detection of CrVI. Moreover, its high capacity for CrVI, which exceeded 230 μg cm–2, facilitates measurement of CrVI in both uncontaminated natural waters and in slightly and heavily contaminated (ppm level) waters. Field deployment of the NMDG-DGT sampler in such waters allowed accurate measurement of time-averaged CrVI concentration, indicating its robustness for in situ measurements of Cr speciation and its potential for further application in the risk assessment of Cr.
AB - Hexavalent chromium (CrVI) is much more toxic and mobile than the trivalent species (CrIII) and consequently, in situ monitoring of CrVI can improve the understanding of Cr biogeochemistry and toxicity in ecosystems. The passive diffusive gradients in thin-films (DGT) technique is a powerful tool for determining metal(loid) speciation, but a binding phase that absorbs only one specific species of Cr is needed. N-Methyl-d-glucamine (NMDG) functional resin was incorporated into the DGT binding phase for selective measurement of CrVI. This NMDG-DGT sampler exhibited a theoretically linear accumulation of CrVI, with negligible accumulation (<5%) of CrIII, even after 72 h deployment. The good prediction of CrVI concentration in synthetic freshwater with NMDG-DGT, even in the presence of 10-time more CrIII, further indicated the sampler’s reliability in selective detection of CrVI. Moreover, its high capacity for CrVI, which exceeded 230 μg cm–2, facilitates measurement of CrVI in both uncontaminated natural waters and in slightly and heavily contaminated (ppm level) waters. Field deployment of the NMDG-DGT sampler in such waters allowed accurate measurement of time-averaged CrVI concentration, indicating its robustness for in situ measurements of Cr speciation and its potential for further application in the risk assessment of Cr.
U2 - 10.1021/acs.est.5b03742
DO - 10.1021/acs.est.5b03742
M3 - Journal article
VL - 49
SP - 14267
EP - 14273
JO - Environmental Science and Technology
JF - Environmental Science and Technology
SN - 0013-936X
IS - 24
ER -