Determination of arsenic in biological samples by slurry sampling hydride generation atomic fluorescence spectrometry using in-situ dielectric barrier discharge trap

Authors: LIU, MEITONG - CHINESE ACADEMY OF AGRICULTURE & MECHANICAL SCIENCES; DING, LAN - JILIN UNIVERSITY; LIU, JIXIN - CHINESE ACADEMY OF AGRICULTURAL SCIENCES; MAO, XUEFEI - CHINESE ACADEMY OF AGRICULTURAL SCIENCES; NA, XING - BEIJING INSTITUTE OF TRADITIONAL CHINESE MEDICINE; Chen, Guoying; QIAN, YONGZHONG - CHINESE ACADEMY OF AGRICULTURAL SCIENCES

Submitted to: Journal of Analytical Atomic Spectrometry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/15/2019
Publication Date: 1/15/2019
Citation: Liu, M., Ding, L., Liu, J., Mao, X., Na, X., Chen, G., Qian, Y. 2019. Determination of arsenic in biological samples by slurry sampling hydride generation atomic fluorescence spectrometry using in-situ dielectric barrier discharge trap. Journal of Analytical Atomic Spectrometry. https://doi.org/10.1039/C8JA00374B.
DOI: https://doi.org/10.1039/C8JA00374B

Interpretive Summary: Arsenic is ubiquitous and extreme toxic to human and biosphere in general. In this work, arsenic in biological samples was analyzed by slurry sampling-hydride generation (SLS-HG) coupled to dielectric barrier discharge atomic fluorescence spectrometry (DBD-AFS). Dilute simple slurry was introduced into an SLS-HG unit. By fulfilling pre-concentration and interference elimination, DBD greatly enhanced sensitivity. The detection limits were 8 pg or 14 pg for 2 mL microbiological or hair sample solutions; the linear range was 0.05 - 300 µg/L; and the recoveries were 93-102% for real samples.

Technical Abstract: Abstract: In this work, the slurry sampling hydride generation (SLS-HG) system was first coupled with the in-situ dielectric barrier discharge atomic fluorescence spectrometry (DBD-AFS) for arsenic analysis in biological samples based on the gas phase enrichment (GPE) principle. After a simple slurry dilution with 5% HCl (v/v) for microbiological and hair samples, a prepared slurry was introduced into the SLS-HG unit for arsine generation under 8 g/L KBH4 in 1.5 g/L KOH. Here, the in-situ DBD apparatus, comprising the three-concentric quartz tubes, was employed to pre-concentrate arsenic to enhance the analytical sensitivity of HG-AFS, as well to eliminate the interference due to the dilution effect and matrix separation. Followed by trapping with 11 kV at 110 mL/min of air carrier gas, and 190 s Ar gas sweeping, arsenic was released with 13 kV at 180 mL/min H2 to the AFS for measurement. Under the optimal conditions, 8 pg or 14 pg detection limit (2 mL sampling) for microbiological or hair sample was achieved without extra pre-concentration, respectively. The linearity R2 exceeded 0.996 ranging from 0.05 to 300 µg/L. The spiked recoveries for real paramecium and micro diatom samples were 93% - 102%, and the measurements were in accordance with the certified reference materials (CRMs) value. The proposed SLS-HG-in-situ DBD-AFS method is extremely suitable to ultratrace arsenic determination in biological samples to protect human’s health and environmental safety.