A5046614042- Mass Spectrometry Techniques and Applications
- Gold and Silver Nanoparticles Synthesis and Applications
- Ion-surface interactions and analysis
- Plasmonic and Surface Plasmon Research
- Analytical Chemistry and Chromatography
- Advanced Memory and Neural Computing
- Biosensors and Analytical Detection
- Organic Electronics and Photovoltaics
- Thin-Film Transistor Technologies
- Nanocluster Synthesis and Applications
- Molecular Junctions and Nanostructures
- Analytical chemistry methods development
- Quantum Dots Synthesis And Properties
- Laser-induced spectroscopy and plasma
- Nonlinear Optical Materials Studies
- Analytical Chemistry and Sensors
- Microfluidic and Capillary Electrophoresis Applications
- Bladder and Urothelial Cancer Treatments
- Renal cell carcinoma treatment
- ZnO doping and properties
- Spectroscopy and Quantum Chemical Studies
- Catalysis and Oxidation Reactions
- Carbon Nanotubes in Composites
- Advanced biosensing and bioanalysis techniques
- Organic Light-Emitting Diodes Research
Tokyo Metropolitan University
2006-2024
Nagoya University
2014
Shikoku (Japan)
2014
Wakayama University
2009-2013
The University of Tokyo
1988-2006
Materials Sciences (United States)
2002
Au/ZnO prepared by coprecipitation exhibited extremely high catalytic activity for low-temperature CO oxidation below room temperature. The was influenced the reduction atmosphere in preparation and heat treatment air before reaction. Reduction of AuIII H2 not only gave smaller Au particles (Au/ZnO (H2-xK), at x = 373–673 K) but also a larger amount Au0 species than did calcination (O2-xK)), resulting better activity. In addition, (H2-xK) markedly enhanced prior to oxidation. Kinetic...
SALDI-MS using TiO 2 nanoparticles induces glycosidic bond cleavage in oligosaccharides via charge separation.
We show development of a laser desorption/ionization (LDI) method with ultrahigh sensitivity by adding gold nanoparticles diameter several tens nanometers into sample solution. In this paper, we succeeded in detection an ultratrace amount molecules, which is less than hundred zeptomoles. This result suggest that the charge interaction based on surface plasmon (SP) excitation very effective for LDI method.
Abstract We demonstrated detection of PEG 1000 on a surface single wall carbon nanotubes (SWCNTs) for surface-assisted laser desorption ionization mass spectrometry (SALDI-MS) by irradiating pulses with wavelengths 532 and 1064 nm. succeeded in observation molecule-related ion coronene no fragmentation visible SALDI-MS measurements.
We have investigated contact and channel resistances of organic field-effect transistors (FETs) based on benzodithiophene (BDT)-dimer films deposited thin pentacene layers used as crystallinity control (CCLs). The resistance source/drain electrodes made conductive instead Au has been reduced for pentacene-CCL/BDT-dimer FETs; the carrier mobility improved to 1.2 cm2 V−1 s−1 at maximum. Because FETs is found be lower than that reference FETs, transport in BDT-dimer more important CCLs high mobility.
We researched contribution of a charge transfer (CT) effect to desorption/ionization mechanism in our ultra-high sensitive laser mass spectrometry based on surface plasmon (SP) excitation (SPLDI-MS). A quantity CT electrons between metal and sample molecules estimated from Raman measurement is correlated signal intensity molecule SPLDI-MS method. system with larger gave higher intensity. Efficient use the would lead development this contribute advancement various fields. [DOI: 10.1380/ejssnt.2009.93]
We investigated ultrafast photoexcited electrons dynamics in relation to the surface enhanced Raman scattering (SERS) effect, using transient reflecting grating spectroscopy method. observed that only SERS-active samples had transfer of from a metal adsorbed molecules within 200 fs followed by return these charge transferred several picoseconds. By analyzing (CT) processes, we were able identify main influential factors adsorption state, stay time at molecules, and quantity CT carriers. That...
Abstract We demonstrated surface-assisted laser desorption–ionization mass spectrometry measurement of oligosaccharides on a titania surface. Insource fragmentation which had never been reported was observed. considered that this caused by surface properties titania, and suggestion may lead to new application SALDI-MS.
Surface plasmon (SP) excitation generated by the attenuated total reflection method was successfully attempted for use as driving force of desorption/ionization in surface-assisted LDI-MS. Our ...
著者らは表面プラズモン励起を金ナノ微粒子の粒子間反発力強化に利用し,2次元配列化過程における凝集を抑制することで,その配列の高秩序化に成功した.走査型電子顕微鏡(SEM)像観察及び分光測定により,表面プラズモン励起された粒子はその配列中孤立化及び凝集体の低サイズ化が促進されていることを確認した.更に,2次元配列中の金ナノ微粒子の高秩序化により,raman測定時における信号再現性の向上と信号の増大が達成された.以上の結果から,著者らの作製した金ナノ微粒子の2次元配列基板が定量性の求められる分子センサーへの応用にむけての大きな一歩と期待される.
Surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) is a valuable technique for detecting small molecules in environmental and medicinal studies. We investigated dot-like 2D-array gold nanoparticle-based SALDI-MS substrates that excite surface plasmons enhance the of sample via charge transfer between substrate molecules. aimed to optimize nondissociative detection by efficiently transferring energy while suppressing excess internal energy. measurements using crystal...
We researched on effect of an organic solvent the preparation a gold nanoparticle two-dimensional array (AuNP 2D-array). AuNP 2D-array substrates were developed by using liquid-liquid interface method. Four solvents (toluene, n-hexane, cyclohexane and diethyl ether) four polar (methanol, ethanol, 1-propanol acetonitrile) examined compared with each other. Crystal violet (CV) molecules substrate measured surface-assisted laser desorption/ionization mass spectrometry; we combinations several...
A survivor of the Hiroshima atomic bomb experienced triple cancer urogenital organs after a long history heavy smoking. The cancers comprised clear cell carcinoma right kidney, transitional carcinomas urinary bladder, left ureter and renal pelvis, adenocarcinoma prostate.
Uniform 2D arrays of metal nanoparticles (NPs) have received significant attention in the field molecular sensing using localized surface plasmon resonance. Generally, NPs bear organic surface-modifying molecules to prevent aggregation and form NP arrays. However, negatively affect sensing. Previously, we developed a technique for forming bare array, denoted sandwich (SW) technique. formation mechanism these remains unknown therefore experimental conditions SW are not optimized. Here,...
We investigated ultrafast photoexcited electrons dynamics in relation to the surface enhanced Raman scattering (SERS) effect, using transient reflecting grating spectroscopy method. observed that only SERS-active samples had transfer of from a metal adsorbed molecules within 200 fs followed by return these charge transferred several picoseconds. By analyzing (CT) processes, we were able identify main influential factors adsorption state, stay time at molecules, and quantity CT carriers. That...
We succeeded to fabricate a two-dimensional array of gold nanoparticles with high-ordering by using the surface plasmon excitation for enhancing repulsive force and controlling aggregation through process fabrication.From SEM observations spectroscopic measurements, we evaluated order while taking account particle isolation.Moreover, provides higher sensitivity reproducibility Raman measurements.From these results, it is expected that our fabricated will lead applications molecular sensor.
We showed that our new single wall carbon nanotubes substrate (SWCNTs substrate) with a nano-sized network structure on its all surface areas was very efficient for high performance ionization of analyte molecules. A preparation procedure SWCNTs requires mainly two processes are well dispersion in preparing solution and thin laying-up base plate. Moreover, we found plates determines analytical SUS plate is good expect further investigation SALDI-MS technique using the leads to more...