Selective and simultaneous high resolution 2-D imaging of AsIII, CrIII and SbIII and dissolved oxygen by developing a new DGT technique comprising a hybrid sensor

July 29, 2022

CRAES, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences uses EasySensor DGT and Planar optode sensor to publish the article as below:


•A new DGT can measure AsIII, CrIII and SbIII selectively for speciation analysis.

•Combining DGT and LA-ICP-MS allows simultaneous 2-D imaging of the three analytes.

•Hybrid PO-DGT sensor allows simultaneous 2-D imaging of AsIII, CrIII and SbIII and O2

•Consumption of AsIII and SbIII appeared in rhizosphere sediment of V. natans.

•Laboratory calibration and validation of the novel DGT (HR-MPTS DGT) was performed.


A new diffusive gradients in thin films technique (HR-MPTS DGT) with mercapto-functionalized attapulgite in a binding gel was developed for simultaneous two-dimensional (2-D) chemical imaging of AsIII, CrIII and SbIII selectively at the submillimeter scale, combined with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis. The HR-MPTS DGT exhibited selective accumulation of AsIII, SbIII and CrIII (> 97%), yet negligible accumulation of AsV, SbV and CrVI (< 2%). Accumulation of AsIII, CrIII and SbIII on the binding gel had a linear relationship (R2 > 0.99) with the corresponding standardized laser ablation signals, proving the feasibility of LA-ICP-MS analysis. Analysis for AsIII, CrIII and SbIII was provided with favorable analytical precision (relative standard deviation <10%). With the purpose of evaluating the dynamics of AsIII, CrIII, SbIII and O2 in the rooting zone, a hybrid sensor, which comprises the HR-MPTS gel overlying an O2 planar optode, was deployed in rhizosphere sediments. Results showed that the consumption of both AsIII and SbIII due to the oxidation extended ~4.48 mm into the sediments, which was consistent with the extension length of the oxidized sediment layers around the roots created by O2 leakage.

Graphical abstract


Arsenic、Chromium、Antimony、Planar optode sensor、Diffusive gradients in thin films


Ren MY, Zhong ZL, Ding SM, et., 2022. Selective and simultaneous high resolution 2-D imaging of AsIII, CrIII and SbIII and dissolved oxygen by developing a new DGT technique comprising a hybrid sensor, Science of The Total Environment, Volume 835, 155460, ISSN 0048-9697, https: //