isotope dilution inductively coupled plasma mass spectrometry isotope dilution inductively coupled plasma quadrupole mass spectrometry ID-ICP-QMS Mass spectrometry where the sample is ionised by a plasma which has been generated by electromagnetic induction. The mass-to-charge ratios of the ions in the sample are then measured whilst the ions are held in a stable orbit by an electric field generated by four parallel electrodes. The relative abundance of isotopes in the sample is determined by using an isotope dilution standard (the sample labelled with a rare isotope). ID-ICP-Q-MS isotope dilution inductively coupled plasma quadrupole mass spectroscopy CHMO:0000513