Simultaneous Sensitive Determination of Selenium, Silver, Antimony, Lead, and Bismuth in Microsamples Based on Liquid Spray Dielectric Barrier Discharge Plasma-Induced Vapor Generation

A highly efficient liquid spray dielectric barrier discharge (LSDBD) plasma-induced vapor generation technique is developed for the simultaneous determination of selenium, silver, antimony, lead, and bismuth in liquid microsamples (20 μL) by inductively coupled plasma mass spectrometry (ICP-MS). It is demonstrated that the dissolved Se, Ag, Sb, Pb, and Bi ions in solution samples are readily and simultaneously converted to volatile species efficiently by LSDBD plasma-induced chemical processes under similar conditions. It eliminates the use of unstable and expensive reducing reagents, and only formic acid is required in the proposed LSDBD chemical vapor generation technique. It is also worth noting that this is the first report of using plasma-induced chemical processes for the vapor generation of Ag and Bi. The simultaneous sensitive determination of Se, Ag, Sb, Pb, and Bi is realized with a sample volume of only 20 μL and the sample throughput could be as high as 180 samples h-1. The limit of detection (LOD) for simultaneous determination of Se, Ag, Sb, Pb, and Bi is 10 ng L-1 (200 fg), 2 ng L-1 (40 fg), 5 ng L-1 (100 fg), 4 ng L-1 (80 fg), and 3 ng L-1 (60 fg), respectively. The precision of Se, Ag, Sb, Pb, and Bi in the present method is evaluated to be better than 4%. The utility of the proposed technique is demonstrated by the analysis of ultratrace Se, Ag, Sb, Pb, and Bi in archaea cells and single conodont samples.