Online Arsenic Species Separation and Analysis of Arsenite, Arsenate, Monomethylarsenate, Dimethylarsonate and Arsenocholine Using Liquid Chromatography and Hydride Generation Atomic Fluorescence Spectrometry
Jinling Guo
Tianjin Key Laboratory of Marine Resources and Chemistry, Department of Marine Chemical Engineering, College of Marine Science and Engineering, Tianjin University of Science & Technology, Tianjin 300457, PR China.
Xiaoping Yu
Tianjin Key Laboratory of Marine Resources and Chemistry, Department of Marine Chemical Engineering, College of Marine Science and Engineering, Tianjin University of Science & Technology, Tianjin 300457, PR China.
Yafei Guo
Tianjin Key Laboratory of Marine Resources and Chemistry, Department of Marine Chemical Engineering, College of Marine Science and Engineering, Tianjin University of Science & Technology, Tianjin 300457, PR China.
Tianlong Deng *
Tianjin Key Laboratory of Marine Resources and Chemistry, Department of Marine Chemical Engineering, College of Marine Science and Engineering, Tianjin University of Science & Technology, Tianjin 300457, PR China.
*Author to whom correspondence should be addressed.
Abstract
Aims: The purpose of this research was to establish a five-arsenic-species separation and analysis method including arsenite [As(III)], arsenate [As(V)], monomethylarsonate (MMA), dimethylarsonate (DMA) and arsenocholine (AsC) in water sample by liquid chromatography with hydride generation atomic fluorescence spectrometry (LC-HG-AFS).
Study Design: The Successful separation and detection for the five arsenic species can be achieved through changing the chromatographic columns and adjusting the compositions of mobile phase.
Place and Duration of Study: Study in the laboratory of College of Marine Science and Engineering at Tianjin University of Science & Technology between March 2014 and September 2014.
Methodology: Firstly the effect of anion exchange chromatography was compared with that of reversed-phase ion-pair chromatography for separating the five arsenic species. Then reversed-phase ion-pair chromatography was selected in the next step because of its universality for separating these arsenic species by adjusting mobile phase.
Results: Effective separation was achieved within 10 min for all the five arsenic species by a single reversed-phase ion-pair chromatographic column eluted with 1 mmol/L diammonium hydrogen phosphate buffer [(NH4)2HPO4] (pH=6.00) + 1% (v/v) CH3OH + 5 mmol/L tetrabutyl ammonium bromide (TBAB). The concentration of arsenic compounds were determined by peak height. And the concentration of AsC, As(III), As(V), MMA, DMA were 250 μg/L, 100 μg/L, 100 μg/L, 100 μg/L, 100 μg/L respectively in this experiment.
Conclusion: The five arsenic species can be effectively separated and detected by hyphenated techniques (LC-HG-AFS).
Keywords: Arsenic species analysis, LC-HG-AFS, reversed-phase chromatography, hyphenated techniques.