基于大气压下介质阻挡放电抑制LA-ICP-MS分析中元素分馏效应研究

A new strategy based on a house-made dielectric barrier discharge (DBD) device to inhibit elemental fractionation effect was developed. The DBD device was connected in between laser ablation cell and ICP torch. The aerosols induced by laser ablation were preionized in the DBD and the particle sizes of aerosol were decreased. The results indicate that elemental time-resolved signals are less fluctuant in DBD mode than normal mode during the laser ablation processes. In the ArF excimer 193 nm LA-ICP-MS, the average precision of signal intensities (RSD, n=3) with DBD mode and normal mode was 1.46% and 4.01%, respectively, and the signal intensities were reduced within 15%. While the average precision and signal intensities were found no significant change in presence and in absence of the DBD device for the 213 nm LA-ICP-MS. No obvious change was obtained for the elemental fractionation index in the 193 nm laser ablation system with the DBD device. The elemental fractionation index was closer to 1 with the DBD for 213 nm LA-ICP-MS. The results demonstrate the elemental fractionation effect was inhibited availably with the DBD device.