Development of single-microdroplet microscope using quantum nature of light and its application to biomoleculer fluctuation

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K05661
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Physical chemistry
• Research Institution: Osaka City University
• Principal Investigator: Sakota Kenji 大阪市立大学, 大学院理学研究科, 准教授 (80346767)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 微小液滴 / イオントラップ / 両親媒性分子

Outline of Final Research Achievements

A single micro droplet can be regarded as a tiny optical resonator. By utilizing the amplification of the light generated in the optical resonator, it becomes possible to detect the molecule dissolved in the droplet with high sensitivity. In this study, we succeeded in the detection of the molecule dissolved in the droplet at about 80 times sensitivity in comparison with the previously-reported equipment by using a home-built three-dimensional ion trap and microscope. In addition, it succeeded in quantitatively measuring the excitation light resonance which the excitation light irradiated to the droplet shows in wide size region. As one of the model biomembrane research, we observed the energy transfer between amphiphilic molecules which were adsorbed on the air-liquid interface in the droplet. It was found that the energy transfer proceeds efficiently in the droplet in comparison with the bulk solution.

Free Research Field

光物理化学

Academic Significance and Societal Importance of the Research Achievements

近年，微小液滴のようなミクロな空間で進行する化学反応は，より大きなスケール（バルク溶液）で進む化学反応とは，本質的な違いがあることが明らかになりつつある．バルク溶液では殆ど進行しない化学反応が，微小液滴では効率的に進行する例も報告されている．本研究によって，微小液滴に溶存した分子を高感度に検出することが可能となった．この方法を応用すれば，バルク溶液と微小液滴での化学反応機構の違いを明らかにできる可能性があり，将来的には，バルク溶液では合成することが困難な薬のような有用物質を微小液滴内で合成することが可能になるなど，創薬分野への波及効果も期待できる．