Developments in analytical technology

摘要

Developments made in ICP-AES (inductively coupled plasma–atomic emission spectrometry) and ICP-MS (mass spectrometry) analytical technology over the last ten years are reviewed, focusing primarily on advancements that have impacted procedures widely available from commercial geochemical laboratories. Examples of this are the increasingly reliability of ICP-MS instrumentation that now makes it a standard production instrument providing trace analysis close to or at crustal abundance for most elements. The other significant change is the development of echelle grating solid-state detector ICP emission instruments. The high resolution offered by the echelle grating coupled with the full range of element selection and wavelength choices have dramatically improved accuracy and reduced costs. Developments in ICP-MS are reviewed, the most notable development being the wider application of high resolution ICP-MS. A magnetic sector mass spectrometer is used either with an electron multiplier detector or with individual mass collectors. The magnetic sector has improved resolution by several orders of magnitude allowing accurate determinations of elements such as Li, Bi, K, Cl, Fe, As, Se and Au at low levels and in difficult matrices. Mass throughput is superior to quadrupole detectors so that detection limits are improved, enabling highly sensitive analysis of vegetation and waters for exploration. Multi-collector (MC) technology allows for isotopic analyses that are comparable to those from thermal ionization mass spectrometry (TIMS). Sample introduction devices such as laser ablation can be used for direct analysis of solids and to determine the composition of mineral grains and inclusions. In this area, MC-ICP-MS can provide superior results to TIMS.