|
|
 |
| » Home » Membership » Awards » List of past recipients » CSJ Award » Hamaguchie
|
|
|
 |
Development of New Time- and Space-resolved Vibrational Spectroscopy and Cultivation of New Frontiers of Physical Chemistry
Vibrational spectra, which are often called gmolecular fingerprintsh provide highly useful and otherwise unobtainable information on the structure, dynamics and microscopic environments of molecules. Dr. Hiro-o Hamaguchi developed a number of novel time- and space-resolved vibrational spectroscopic methods and applied them to selected molecular systems of basic importance, from a molecule to a living cell, and thereby cultivated new frontiers of physical chemistry. His achievements are summarized as follows
| |
Prof. Hiro-o Hamaguchi
The University of Tokyo
|
|
1. Developments of novel time- and space-resolved spectroscopic methods
Since early 80fs, Dr. Hamaguchi constructed a number of new time-resolved vibrational spectroscopic systems, including nanosecond Raman, microsecond infrared, picosecond Raman, nanosecond infrared, picosecond time- and frequency 2D CARS and millisecond multichannel FT infrared systems. These spectroscopic systems were all unique to Dr. Hamaguchifs group and gworld only oneh. He applied these new methodologies to many dynamic molecular systems of fundamental importance, like photochemical reactions in condensed phase, electric-field induced molecular orientations in liquids and growth and death of a single living cell. In the last decades, he turned to time- and space-resolved vibrational spectroscopy and developed novel non-linear vibrational imaging techniques including multiplex CARS (Coherent Anti-Stokes Raman Scattering) and Hyper-Raman scattering. Applications of these vibrational imaging techniques are now rapidly expanding in many research fields, in particular, in living cell studies.
2. Elucidation of the mechanisms of photochemical reactions
Photochemical reactions are important prototypes of chemical reactions that can be suitably studied by time-resolved spectroscopies. Whenever Dr, Hamaguchi constructed a new spectroscopic system, he applied it to retinal, which is a model system for cis/trans photoisomerization and which is known to play important roles in a number of photobiological events like vision and photo-sensing. Combining the results obtained by nanosecond Raman, picosecond 2D CARS, nanosecond infrared, femtosecond ultraviolet/visible studies, Dr. Hamaguchi established a global view on the photoisomerization of retinal that consists of trans to cis isomerization through the second lowest excited singlet state and cis to trans isomerization through the lowest excited triplet state. In addition to the photoisomerization reaction of retinal, Dr. Hamaguchi elucidated the mechanisms of the photoisomerization of trans-stilbene, photoinduced intramolecular electron transfer of N,N-dimethylaminobenzonitrile, photoinduced intermolecular electron transfer of biphenyl, hydrogen abstraction reaction of benzophenone and related compounds, photochromism of salycilidene aniline, photoinduced chlorine abstraction of aromatic compounds, photoinduced double-proton transfer of 2-aminopyridine/acetic acid complex and so on.
3. In vivo observation of molecular transformations in single living cells and physicochemical elucidation of cell activities
Studying biological events in a living cell by reducing them into elementary molecular processes is on the line of physicochemical studies of chemical reactions, in which the structure and dynamics of reaction intermediates are the basis of understanding. By using time- and space-resolved Raman spectroscopy, Dr. Hamaguchi succeeded for the first time in observing the molecular level transformations inside a living cell of fission yeast (S. Pombe) during its mitosis. He found an intense Raman band at 1602 cm-1 that sharply reflected the metabolic activity of mitochondria of a living yeast cell and called it the gRaman spectroscopic signature of lifeh. This signature has attracted much attention for its potentiality as a direct in vivo measure of the viability and life of a living cell. Dr. Hamaguchi also succeeded in tracing the whole process of starving death of a yeast cell by using the time-resolved Raman imaging of the gRaman spectroscopic signature of lifeh, phospholipids, polyphosphates and proteins. These pieces of work have opened up new fields of physical chemistry that looks at single living cells in vivo and real time and elucidate the cell activity at the molecular level.
In summary, Dr. Hamaguchi developed a variety of new spectroscopic methods, placing a focus on time- and space-resolved vibrational spectroscopy, and led the world progress of molecular spectroscopy. He cultivated new frontiers of physical chemistry by applying his new methods to fundamental molecular problems including photochemical reactions in condensed phase and biological molecular transformations in single living cells. These achievements of Dr. Hamaguchi are highly appreciated internationally and well deserve the Chemical Society of Japan Award.
|
|
 |
|
