Development and evaluation of diffusive gradients in thin-films technique with a novel titanium peroxide binding gel for in situ measurement of Tl in natural waters and sediments

Hongmei Deng; Meiling Liu; Zhaodong Liu; Minhua Su; Yue Gao; Danxing Yang; Yuxuan Liu; Liang Ma; Zhiqiang Yu; Tangfu Xiao; Jun Luo

doi:10.1016/j.jhazmat.2023.131976

Development and evaluation of diffusive gradients in thin-films technique with a novel titanium peroxide binding gel for in situ measurement of Tl in natural waters and sediments

J Hazard Mater. 2023 Sep 15:458:131976. doi: 10.1016/j.jhazmat.2023.131976. Epub 2023 Jun 30.

Authors

Hongmei Deng¹, Meiling Liu², Zhaodong Liu³, Minhua Su², Yue Gao⁴, Danxing Yang³, Yuxuan Liu², Liang Ma², Zhiqiang Yu⁵, Tangfu Xiao², Jun Luo⁶

Affiliations

¹ School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China; Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China; State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
² School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China; Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.
³ State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
⁴ Research Unit of Analytical, Environmental and Geochemistry (AMGC) Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium.
⁵ State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
⁶ State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China. Electronic address: esluojun@nju.edu.cn.

PMID: 37406523
DOI: 10.1016/j.jhazmat.2023.131976

Abstract

Speciation of thallium (Tl) controls its fate and biogeochemical behaviors. Thus, a sensitive and accurately approach for Tl monitoring is of great demand due to its ultra-low concentration and sensitivity to redox change. In this study, diffusive gradients in thin-films technique (DGT) assembled with novel titanium peroxide (TP) binding gels (TP-DGT) was developed for in situ measurement of dissolved Tl(I) and Tl(III) in waters and sediments. Laboratory test showed a linear mass accumulation of Tl(I) and Tl(III) on the TP binding gels with the deployment time from 4 to 72 h. A fascinating performance of this novel DGT was achieved in a pH range of 4-9, ionic strength range of 0.1-200 mmol L^-1, and humic acid concentration of 0-30 mg L^-1 with a low detection limit of 0.3 ng L^-1 for Tl(I) and 0.6 ng L^-1 for Tl(III). The TP binding gels own excellent stability (1-365 d) and high capacity (73.5 μg Tl disc^-1) which are suitable for long-term monitoring. Field application in a river indicated that TP-DGT could work effectively, comparable to the grab sampling in waters. For the first time, the TP-DGT coupled with oxygen optode was successfully applied to map 2D distribution patterns of Tl and oxygen simultaneously in the rhizosphere of M. verticillatum L. This study confirms TP-DGT is a promising tool for routine monitoring of Tl in waters and for investigating biogeochemical processes of Tl in sediments.

Keywords: Diffusive gradients in thin-films (DGT); M. verticillatum L; Thallium; Titanium peroxide (TP).