Date: 16:00-18:00, Friday, January 10, 2020
Place: 3F, Lecture room, Main Chemistry Build.
Speaker：Takafumi Hirata
日 時：2020年1月10日（金）16:00-18:00
場 所：化学本館3階講義室
講演者：平田岳史
講演者1：平田岳史（Takafumi Hirata)
Title: Pushing the Limits in Mass Spectrometry
The mass spectrometer utilising an atmospheric pressure plasma as an ion source (ICP-MS) is likely to become a significant and cost-effective tool for many isotopic measurements. Recent progress in the ICP-MS technique is dramatic improvements in precision and accuracy of the isotopic ratio measurements. Moreover, laser ablation sampling technique combined with the ICP-MS technique (LA-ICPMS) is now widely accepted as one of the most sensitive and rapid analytical tools for elemental and isotopic analysis of solid materials. However, we should not be too hasty to open the champagne, as there remain many problems to be solved in order to make it a truly routine and mature analytical tool, and experimentation still remains crucial. Faced with this, we are still struggling to achieve better analytical results or capability of the technique. One of the major development in the laser technology to come to light in these ten years was the recent application of a femtosecond (fs) lasers for solving various microanalytical problems, and several groups have been independently employing this technology. More importantly, we have developed a multiple spot laser ablation protocol for further reliable and accurate elemental determinations using an in-house femtosecond laser ablation systems equipped with a Galvanometric optics. With the Galvanometric optics, a standard addition method can also be applied by mixing of aerosols released from sample and standard references. The mixing ratio [sample : standard] can be controlled by changing the number of laser shots for each component. The Galvanometric optics can provide flexible calibration protocols for elemental analysis, where no proper (matrix-matched) calibration standard is available. Another important progress achieved in our research group is the new analytical system for elemental and isotopic analysis of nanoparticles using the ICP-MS technique. We have developed new multiple ion counting system for the ICP-MS aiming at to obtain quantitative elemental data from transient signals induced from NPs. With the system developed here, we have measured Re/Os (185Re/188Os) and 187Os/188Os ratios from NPs. The data obtained here demonstrated clearly that the high-time resolution-multiple collector-ICP-MS (HTR-MC-ICP0MS) technique can become a powerful tool to monitor the elemental and isotope ratios from NPs of multiple components. Finally, new ICP-MS system utilising a time-of-flight type mass spectrometer (ICP-TOF) was finally installed in end of 2019. The ICP-TOF system can be applied for both the multi-element determinations from NPs and fast-elemental imaging analysis for biological tissue sample (bio-imaging analysis). With the series of brand mass spectrometers and laser ablation systems, we are going to develop completely new analytical systems aiming at creating a new research fields in both geochemistry and biochemistry. Potential capability of our research group over the traditional geochemistry facility will be highlighted in this talk. Das Beste oder nichts.