Determination of inorganic and organomercury compounds by high-performance liquid chromatography-inductively coupled plasma emission spectrometry with cold vapour generation

Abstract
An inductively coupled plasma (ICP) emission spectrometer was used as a high-performance liquid chromatographic detector for the determination of mercury compounds. Post-column cold vapour generation was used to obtain improved detection limits. The replacement of the conventional polypropylene spray chamber of the ICP by an all glass chamber is described. A comparison of band broadening indicates that the glass chamber is useful when a severe memory effect is observed with the polypropylene spray chamber. Detection limits ranged from 32 to 62 p.p.b. of mercury for four mercury compounds, based on a signal to noise ratio of 2:1. This represents a three to four order of magnitude enhancement over detection limits obtained without cold vapour generation. The approach is linear over three orders of magnitude. A blind, spiked distilled water study illustrates the reproducibility and accuracy of the method.