Liquid Chromatography coupled to Isotope Ratio Mass Spectrometry (LC-IRMS): a review

An accurate analysis of the composition of stable isotopes is today an increasingly important requirement in various fields of science (from the environmental to the medical field). Since 2004, the year of its introduction on the market, Liquid Chromatography coupled with Isotope Ratio Mass Spectrometry (LC-IRMS) has expanded the applications possible with the most famous and widespread Elemental Analyzer (EA) and Gas Chromatography Combustion (GC-C)-IRMS techniques. The new liquid chromatography interface coupled with IRMS opened to new application areas, in particular by enabling compound-specific δ13C analysis of non-volatile, water-soluble compounds from complex mixtures. The advantages of the technique include the possibility of performing a compound-specific analysis without altering isotopic signatures by derivatization. Applications in paleoarchaeology, nutrition and trophic, pediatrics, soil science and food authenticity are examined here by reporting on the progress and technical constraints.