An Infrared-heated Sample Introduction System for Inductively Coupled Plasma Mass Spectrometry

This work involves heating the entire commercially available sample introduction system on a Varian 820MS instrument with off-the-shelf infrared heaters. This heating improves sensitivities by a factor of 2 to 16 times, with high mass elements receiving the greatest improvement. It also improves detection limits by a factor of 1.1 to 3.5 times for most analytes. At the price of doubled oxide formation, the formation of doubly charged species was decreased by a factor of 3. The Be-9(+)/Li-7(+) signal ratio, an indicator of plasma robustness, increased from 0.174 to 0.235 with infrared heating. The infrared-heated system enabled the accurate analysis of a drinking water standard reference material (SRM) (for Be, Mg, Al, Cr, Mn, Co, Cu, Zn and As) and of a waste water SRM (for Be, Mg, Cr, Mn, Co, Cu, Zn, Cd, and Pb) by simple external calibration.