The 82nd JSAP Autumn Meeting 2021

Presentation information

Oral presentation

4 JSAP-OSA Joint Symposia 2021 » 4.1 Plasmonics and Nanophotonics

[10p-N404-1~14] 4.1 Plasmonics and Nanophotonics

Fri. Sep 10, 2021 1:00 PM - 5:45 PM N404 (Oral)

Prabhat Verma(Osaka Univ.), Nicholas Smith(Osaka Univ.)

5:30 PM - 5:45 PM

[10p-N404-14] Control and measurement of nano/micro-space temperature that changes cellular behavior

Noriko Hiroi1, Takayuki Nakamura2, Takaya Saito2, Ryuichi Tanimoto2, Takahiro Yamada2, Akira Funahashi2, Atsushi Taniguchi3, Shigenori Nonaka3, Joe Sakamoto3, Yasuhiro Kamei3, Makoto Tominaga4, Yuki Yanase5, Hiroko Kishi6, Kohki Okabe7 (1.Keio Univ. GM, 2.Keio Univ. SE, 3.Nat Inst. Basic Biol, 4.Nat Inst. Physiol, 5.Hiroshima Univ., 6.Yamaguchi Univ., 7.the Univ. Tokyo)

Keywords:semiconductor, quantum dot, plasmon

To correctly understand various phenomena in living organisms, new insights can be obtained not only by relative observation but also by quantitative measurement of physical parameters. Among the physical parameters that are currently attracting attention is the temperature in the tiny space of a cell. In a small space, a difference of 1 K in temperature may result in a large energy flow. As a result, changes in the intracellular reaction environment and consequent changes in the reaction network are thought to occur.
To date, various methods have been developed to measure intracellular temperature, but in this presentation, we will mainly discuss the method of intracellular temperature measurement using quantum dots.
In quantum dots, electrons receive energy from light and are excited, and this energy is emitted as light with the formation of photo-induced defects. Compared to many fluorescent materials, quantum dots are characterized by their ability to absorb energy from a wide range of light wavelengths, their limited emission wavelength, and their resistance to fading. In semiconductors, not just quantum dots, the efficiency of energy transferring via electrons, depends on temperature. The higher the temperature, the smaller the value of energy exchanged with light. Therefore, we may observe the following temperature dependency that the higher the temperature, the longer the wavelength of the fluorescence emitted. Using this property, it is possible to read the temperature from the change in the fluorescence wavelength of a quantum dot incorporated into a cell.
Examples of temperature measurement by quantum dots of fibroblasts induced cellular movement with intracellular signaling and with localized infrared stimulation will be presented in comparison with using fluorescence lifetime or surface plasmon resonance applications.