A total consumption (up to 75 μL min−1) infrared-heated sample introduction system for inductively coupled plasma optical emission spectrometry

Abstract

This study compares the analytical figures of merit of inductively coupled plasma optical emission spectrometry (ICPOES) with an infrared (IR)-heated modified cyclonic spray chamber (MC) system providing total sample consumption at up to 75 μL min¹, Apex E desolvation system and IsoMist programmable temperature spray chamber. A baffled cyclonic spray chamber (BC) at room temperature was used as a reference sample introduction system. Sample uptake rates of 25, 50 and 75 μL min⁻¹ were tested. Under operating conditions providing a compromise in sensitivity and robustness, and at a sample uptake rate of 50 μL min⁻¹, the improvement in the sensitivity and detection limit of the MC and Apex was comparable and significantly higher than that for IsoMist. However, at a sample uptake rate of 75 μL min⁻¹, the order of the improvement in the sensitivity and detection limit was Apex > MC > IsoMist. In general, at sample uptake rates of 50 and 75 μL min⁻¹ and in contrast to IsoMist, the sensitivity and detection limit for the MC and Apex were not decreased against those obtained with the BC at a regular sample uptake rate of 1 mL min⁻¹. The MC system provided the highest plasma robustness. At a given sample uptake rate, the MC also provided a shorter washout time than Apex and IsoMist. Accurate ICPOES analysis of two certified reference materials of drinking and waste waters was performed with the MC using a simple external calibration without internal standardization and the results were similar to those obtained for the BC, IsoMist and Apex. This demonstrates the suitability of the MC as a sample introduction system for ICPOES.