Hg speciation by differential photochemical vapor generation at UV-B and UV-C wavelengths

Authors: Chen, Guoying; Lai, Bun-Hong; MEI, NI - Shanghai Institute For Food And Drug Control; LIU, JIXIN - Beijing Titan Instruments Co; MAO, XUEFEI - Chinese Academy Of Agricultural Sciences

Submitted to: American Chemical Society National Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 6/22/2016
Publication Date: 8/24/2016
Citation: Chen, G., Lai, B., Mei, N., Liu, J., Mao, X. 2016. Hg speciation by differential photochemical vapor generation at UV-B and UV-C wavelengths [abstract]. American Chemical Society National Meeting. 252(16):1.

Interpretive Summary:

Technical Abstract: Mercury speciation was accomplished by differential photochemical reduction at two UV wavelengths; the resulting Hg(O) vapor was quantified by atomic fluorescence spectrometry. After microwave digestion and centrifugation, analyte solutions were mixed with 20% (v/v) formic acid in a reactor coil, and exposed sequentially to narrow-band UV-B fluorescence lamps and a low-pressure UV-C Hg discharge lamp. The signal intensity under each wavelength was linked to Hg(++) and MeHg(+) concentrations in a linear equation. After slopes of standard curves were acquired, concentrations of both Hg species in unknown samples were calculated. Elimination of chemical separation lowered chemical and labor costs and improved throughput. This method achieved 0.087 and 0.016 ng/g limit of detection for Hg(++) and MeHg(+), respectively, and 98-104% recoveries at 10 ng/g, and was validated with certified referential material.