Trends in Analytical Developments and Earth Science Applications in LA-ICP-MS and LA-MC-ICP-MS for 2004 and 2005

This review of laser ablation-inductively coupled plasma-mass spectrometry includes research that employed quadrupole instruments, and single-collector and multicollector magnetic sector field instruments. The most important trend in 2004–2005 was the growing appreciation that small matrix effects in LA-(MC)-ICP-MS need to be addressed in order to produce highly precise and accurate data by the method. The issue is most acute for isotope ratio measurements that require standard-sample-standard bracketing but can also be important for certain elemental analysis. Matrix-dependent elemental and isotopic fractionations were studied from the standpoint of laser-sample interactions and the behaviour of laser-generated particles in the ablation cell, transfer tubing and ICP torch. Innovations in LA-(MC)-ICP-MS involved signal smoothing, in torch laser ablation, on-line isotope dilution and molecular oxide monitoring. Other important research was carried out on the calibration and homogeneity of various reference materials; and the exploration of mature ( in situ U-Pb geochronology) and emerging (apatite fission-track chronometry, U-Th/He thermochronology, boron/strontium/uranium-series isotopic microanalysis) applications in the Earth sciences.