Using the installed spray chamber as a gas-liquid separator for the determination of germanium, arsenic, selenium, tin, antimony, tellurium and bismuth by hydride generation inductively coupled plasma mass spectrometry

Abstract

The spray chamber installed in an ICP-MS instrument was successfully used with minor modifications as a gas–liquid separator for a hydride generation (HG) ICP-MS system. Common problems associated with the coupling between HG and ICP, i.e., plasma instability, severe memory effects and high blanks, were reduced. This was partly due to the inherent features of the spray chamber, i.e., double pass, water-cooled at low temperature (8 °C), and controlled waste drainage, and partly to the selection of suitable chemical reagents. Universally optimized conditions for NaBH₄ input rate, acid type and acid concentration were not achievable. However, even under compromise conditions, the slope was above 5000 counts s^–1(µg l^–1)–1, the blank equivalent concentration was below 0.04 µg l^–1 and the limit of detection was better than 0.01 µg l^–1 for most elements/isotopes when the proposed system was applied to the determination of hydride-forming elements in a standard reference material (NIST SRM 1643c Water).