Quantitative LA-ICP-MS imaging of platinum in chemotherapy treated human malignant pleural mesothelioma samples using printed patterns as standard

LA-ICP-MS has often been applied for the analysis of trace elemental distributions in biological tissues. However, the strong matrix dependence of LA-ICP-MS analyses and highly variable matrix conditions aggravate reliable qualitative distribution analyses and thus for obtaining quantitative information elaborate quantification strategies have to be applied. In this work printed patterns on paper with thin gold layers as pseudo-internal standard have been proposed as an alternative approach to the commonly used matrix-matched tissue standards. Besides a major reduction of the workload for standard preparation the presented method allows for compensation of instrumental drifts during measurement as well as a reduction of matrix related effects. The developed method has been verified using matrix-matched tissue standards (deviations from the actual metal content less than 5% with relative standard deviations of less than 7%) and applied to platinum imaging on human malignant pleural mesothelioma samples after administration of individuals with platinum containing cytostatic drugs. Printed patterns on paper are presented as an alternative quantification method to matrix-matched tissue standards in LA-ICP-MS imaging experiments.