A novel photochemical vapor generator for ICP-MS determination of As, Bi, Hg, Sb, Se and Te

Abstract

A scheme of determination of As, Bi, Hg, Sb, Se and Te with photochemical generation of their volatile derivatives and inductively coupled plasma mass spectrometry (ICP-MS) detection was developed. The volatile compounds were produced using a novel photochemical reactor with direct contact of a sample with an ultraviolet (UV) lamp. Essential experimental parameters such as the concentrations of the reagents and the flow rates of the carrier gas and the sample were optimized. For each element, individual optimum values of these parameters were obtained. The detection limits in the optimal single element modes for As, Bi, Hg, Sb, Se and Te were 0.5, 13, 0.6, 0.3, 0.4 and 0.7 ng L−1 respectively. Compromise conditions were determined for simultaneous multielement analysis. The increase of the detection limit for each element in the multielement mode was experimentally estimated. The applicability of the proposed scheme was demonstrated by analysis of certified reference samples of water and fish muscle. Acceptable accuracy of determination of As, Se, Sb, Te and Hg in samples of local lake water was proved by spike recovery test. Possible matrix effects were screened using Placket-Berman design and further examined in detail.