Improvement of ICP-MS measurement method for ⁹⁰Sr in hard tissue samples

Analytical methods with inductively coupled plasma mass spectrometry (ICP-MS) have been developed for determination of ⁹⁰Sr in hard tissues; however, the sensitivity and reproducibility of the ICP-MS method are insufficient to measure trace amount of ⁹⁰Sr in hard tissues. In this study, we improved the ICP-MS method by removal of resin-derived organic materials and application of multi-quadrupole ICP-MS (ICP-multiQMS). An uncoated inert polymeric supported resin (Pre-filter resin, Eichrom technologies) effectively removed resin-derived organic materials and improved reproducibility of ⁹⁰Sr measurement with ICP-MS. ICP-multiQMS achieved low-level abundance sensitivity (ratio of interference signal at m/z=90 to ⁸⁸Sr signal) and low limit of detection for ⁹⁰Sr measurement. The newly developed ICP-MS analytical method by combining the removal of organic materials using pre-filter resin with ICP-multiQMS provide a powerful tool for the investigation of ⁹⁰Sr in hard tissues. (author)