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Updated: May 2, 2026

Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies
Published on: July 1, 2016
Selective sampling and measurement of Cr (VI) in water with polyquaternary ammonium salt as a binding agent in
Hong Chen1, Yang-Yang Zhang1, Ke-Li Zhong1
1College of Chemistry, Chemical Engineering and Food Safety, Bohai University, China; Research Institute of Food Science, Bohai University, China; Food Safety Key Lab of Liaoning Province, Jinzhou 121013, China.
Abstract:
A diffusive gradients in thin films (DGT) device with polyquaternary ammonium salt (PQAS) as a novel binding agent (PQAS DGT) combined with graphite furnace atomic absorption spectrometry (GFAAS) was developed for the selective sampling and measurement of Cr (VI) in water. The performance of PQAS DGT was independent of pH 3-12 and ionic strength from 1 × 10(-3) to 1 molL(-1). DGT validation experiments showed that Cr (VI) was measured accurately as well as selectively by PQAS DGT, whereas Cr (III) was not determined quantitatively. Compared with diphenylcarbazide spectrophotometric method (DPC), the measurement of Cr (VI) with PQAS DGT was agreement with that of DPC method in the industrial wastewater. PQAS-DGT device had been successfully deployed in local freshwater. The concentrations of Cr (VI) determined by PQAS DGT coupled with GFAAS in Nuer River, Ling River and North Lake were 0.73 ± 0.09 μg L(-1), 0.50 ± 0.07 μg L(-1) and 0.61 ± 0.07 μg L(-1), respectively. The results indicate that PQAS DGT device can be used for the selective sampling and measurement Cr (VI) in water and its detection limit is lower than that of DPC method.

