Rhenium-cup in-torch vaporization inductively coupled plasma atomic emission spectrometry for liquid, slurry or solid micro-samples

Abstract

In rhenium-cup in-torch vaporization (ITV) sample introduction for inductively coupled plasma atomic emission spectrometry (ICP-AES), a rhenium (Re) cup, which is formed from a thin Re foil, acts as the sample-carrying probe. The sample-carrying probe is inserted in a vaporization chamber which clips onto a typical ICP torch. The effect of carrier gas (Ar–∼3%H2 mixture) flow rate and cup insertion position on analyte emission characteristics were examined for several elements (e.g., Pb, Zn, Cd, Mn, Mg, V, Sr, and Be) that had different vaporization characteristics and emission lines that covered a wide spectral range. Calibration curves were linear, precision ranged between 2.4 and 4.7% (peak heights) and between 1.2 and 6.0% (peak areas) and detection limits were in the pg to fg range. Due to the use of cups, ITV-ICP-AES can now be used with µL volumes of liquids and for direct (i.e., minimum sample pre-treatment) elemental analysis of slurries or solid micro-samples as well.