The Mass Spectrometry society of Japan - The 68th Annual Conference on Mass Spectrometry, Japan

Abstract

Poster Presentations

Day 3, May 13(Wed.)  Poster (1008/09)

Pt isotopic signature of nanoparticles in meteorites analyzed by high-time resolution multiple collector ICP-Mass spectrometry (HTR-MC-ICP-MS)

(Univ. Tokyo)
oNorika Numa, Masaki Nakazato, Shuji Yamashita, Takafumi Hirata

Both the origin and transport mechanism of heavy elements (Fe–U) are important to decode the chemical evolution of the Galaxy. Isotopic signatures of the nano-sized grains preserved in meteorites can provide key information concerning the nucleosynthetic processes of the heavy elements. In this study, we have developed a new mass spectrometric technique using multiple collector-ICP-mass spectrometer equipped with high time-resolution data acquisition system (HTR-MC-ICP-MS) to obtain isotopic ratio data from individual nanoparticles (NPs) in meteorites. To evaluate the accuracy of data obtained by this method, isotopic ratios of 195Pt/194Pt for commercially available Pt NPs were measured. The 195Pt/194Pt ratio data obtained in this study revealed that the resulting precisions in the isotopic ratio measurements were mainly controlled by the Poisson counting statistics. The analytical technique developed here was applied to measure 195Pt/194Pt and 196Pt/194Pt ratios for NPs which were extracted from Allende meteorite through the laser ablation in liquid (LAL) technique. Among these samples, 80 nano-sized grains in total with Pt were detected and measured for their isotopic signatures. We will present the variation of the measured Pt isotopic ratios for meteoritic NPs to discuss the possible nucleosynthetic process of Pt isotopes.