Inductively coupled plasma mass spectrometry : fundamental studies

Abstract: Inductively coupled plasma mass spectrometry (ICP-MS) is in focus in this thesis. Fundamental studies of ICP double focusing magnetic sector MS are presented, and some possible applications are discussed. One of the recent innovations for increasing the sensitivity of ICP-MS is to use a Pt-shield inserted between the coil and the torch, which can be grounded. It is known that use of a shielded torch results in gain in sensitivity as well attenuation of the secondary discharge, but other physical parameters change as well. Thereby a thorough study of a torch with a Pt guard electrode has been performed in order to address these questions. Matrix effects from seawater samples are described. Isotope ratio measurements can be performed using ICP-MS. The raw data collected needs to be mathematically corrected for mass discrimination factors as well as detector dead time. A model is presented herein with which both these factors can be determined from calibration curves.