The use of inductively coupled plasma mass spectrometry as a detector in drug metabolism studies

Background: The inherent properties of element selectivity combined with high sensitivity and structure independent response, make inductively coupled plasma mass spectrometry (ICP-MS) an interesting alternative detection technique in drug metabolism studies. Objective: The application of online separation with ICP-MS detection in drug metabolism studies is reviewed with focus on the merits and demerits of this detection technique. The prerequisite for inclusion in this review is that the study involves a separation technique hyphenated online to the ICP-MS detection. Resultlconclusion: ICP-MS detection is found to be advantageous for analysis of all drug substances detectable by ICP-MS compared to radiochemical detection. Detectable drugs are limited to halogen-, sulfur-, metal- and metalloid-containing compounds. The drawback of interference from enclogenous compounds on quantitative mass balance estimations of non-metal drugs is addressed. The potential of determining the stoichiometry in metallo-drug biomolecule interactions is pointed out by presenting examples of simultaneous monitoring of metals in metallo-drugs and intrinsic ICP-MS detectable elements in biomolecules. it is concluded that ICP-MS detection is an indispensable technique in drug metabolism studies of metallo-drugs, although the applicability for traditional drugs is limited.