Analysis of geoporphyrins by high-temperature gas chromatography inductively coupled plasma mass spectrometry and high-performance liquid chromatography inductively coupled plasma mass spectrometry. Plenary lecture

Abstract

High-temperature gas chromatography (HTGC) and high-performance liquid chromatography (HPLC) have been coupled to inductively coupled plasma mass spectrometry (ICP-MS) for the determination of geopophyrins from oils shales. A New, directly heated stainless-steel capillary interface was used to introduce the eluent into the ICP torch. The interface was robust, simple to install, programmable and introduced minimal loss (5–10%) in chromatographic efficiency. The HTGC–ICP-MS was used for rapid metal fingerprinting of the geoporphyrin fractions. Cobalt, Chromium, iron, nickel, titanium, vanadium and zinc metalloporphyrins were fingerprinted. For quantitative analysis HPLC–ICP-MS was preferred. Quantitative data obtained by HPLC–ICP-MS and HPLC with UV absorption detection of nickel geoporphyrins from Julia Creek and Serpiano oil shales showed good agreement. Levels of nickel porphyrins were in the range 15–120 µg g^–1 in the samples analysed. The potential for multi-element, multi-isotopic detection is clearly illustrated using up to ten elements/isotopes virtually simultaneously.