Arsenic species analysis by ion chromatography–bianode electrochemical hydride generator–atomic fluorescence spectrometry

In this work, a novel hyphenated technique ion chromatography–bianode electrochemical hydride generator–atomic fluorescence spectrometry (IC–BAECHG–AFS) system was developed for on-line simultaneous analysis of arsenite (As(III)), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), and arsenate (As(V)). Parameters that might affect hydride generation efficiency were investigated and the interference of various ions was also examined. Under the optimal conditions, the hydride generation efficiency of bianode electrochemical hydride generator (BAECHG) was close to the hydride generation efficiency of chemical hydride generator (CHG). The linear ranges were 5–200 μg L−1 for As(III), DMA and MMA and 10–200 μg L−1 for As(V). The limits of detection (LOD, S/N = 3) were 3.04, 4.27, 3.97 and 9.30 μg L−1 for As(III), DMA, MMA and As(V), respectively. The relative standard deviations (RSD, n = 7) of As(III), DMA, MMA and As(V) were 4, 3, 5 and 4%, respectively. The proposed method was also applied to the determination of the four arsenic species in dental pulp inactivative agent (type I). The recoveries of the four arsenic compounds were in the range of 91.6–103.2%.