Physics Molecular physics

Osaka Metropolitan University researchers have used the power of laser light to accelerate the reaction between cancer cell-derived extracellular vesicles—a kind of nanoparticle—and antibody-modified microparticles. The three-dimensional structure of the resulting aggregates was then analyzed using a confocal optical system. The results demonstrated the ability to measure, within 5 minutes, approximately 1,000 to 10,000 nanoscale EVs contained in a 500 nL sample.

An Osaka Metropolitan University joint research group has discovered that near-infrared absorbing dyes, which had previously been considered to have closed-shell electronic structures, have an intermediate electronic structure, between closed- and open-shell structures. They also found that as the wavelength of near-infrared light that can be absorbed becomes longer the contribution of open-shell forms increases within the dye. These newly discovered characteristics are expected to be utilized to develop new near-infrared absorbing dyes that can absorb longer wavelength near-infrared light.

Osaka Metropolitan University researchers have used 100 seconds of laser irradiation to generate convection currents that selectively accelerate biochemical reactions—due to the photothermal effect—by concentrating biofunctional molecules at the cell surface. Using this method, useful molecules can be transported into cells at concentrations a hundred to a thousand times lower than with conventional methods. Furthermore, they also succeeded in selectively introducing small molecules into intracellular organelles usually impossible at low concentrations (hundreds of pmol/L) as well as inducing cell death in targeted cells by concentrating anticancer active peptides into them at concentrations so low that they would not be conventionally effective (several tens of nmol/L).

Researchers from Osaka Metropolitan University have developed principles and technologies of nanofluidic devices to freely manipulate nanomaterials, biomaterials, and molecules at the single-molecule level using fundamental technologies such as nanofluidic processing, functional integration, and fluidic control and measurement, which has pioneered the way to integrate various fields under nanofluidics.

A research group, at the Osaka Metropolitan University Graduate School of Engineering, has succeeded in measuring spin transport in a thin film of αNPD molecules—a material well-known in organic light emitting diodes—at room temperature. They found that this thin molecular film has a spin diffusion length of approximately 62 nm, a length that could have practical applications in developing spintronics technology. In addition, while electricity has been used to control spin transport in the past, the thin molecular film used in this study is photoconductive, allowing spin transport control using visible light.

Osaka Metropolitan University scientists discovered the principle of light-induced acceleration of antigen–antibody reaction, allowing for simple, ultrafast, and highly sensitive detection of proteins. The researchers introduced target proteins and probe particles with modified antibodies selectively binding to the target proteins into a small channel and applied irradiation with infrared laser light. They achieved, for the first time, the rapid measurement of trace amounts of attogram-level target proteins after only 3 minutes of laser irradiation. These findings will potentially contribute to breakthroughs in the development of systems for ultra-early diagnosis of various diseases.

Linked lanthanides shine light on crystal engineering, New technique reveals hidden genome, Red, white and blue alerts for dangerous bacteria & Windows gain competitive edge over global warming. Read all in the September's Editor's Choice plus this month's Asia Research News 2022 magazine pick - Floating sensors to gather ocean data.

Rare earth metals, when linked, can act as a conduit for energy flow, and show promise for the development of novel materials.

A research group led by Professor Yoshio Teki of the Osaka Metropolitan University Graduate School of Engineering has succeeded in developing a new pentacene derivative that is more than 100 times more photostable than TIPS-pentacene, a photostable pentacene derivative. Additionally, the team has further clarified the ultrafast excited state dynamics in this system. In the pentacene moiety of this system, we were able to demonstrate that the transition from the excited singlet state to the excited triplet state occurs ultrafast in the time region of a 10-13 seconds. In purely organic materials without heavy atoms such as rare metals, such intersystem crossing usually occurs on time scales longer than 10-9 seconds. The empirical results of this study are expected to be applied as a method for stabilizing and developing light-unstable materials in the future.

Researchers at the Institute of Industrial Science, The University of Tokyo studied the anomalous properties of amorphous solids, including glasses, using computer simulations, and found a common vibrational mechanism underlying them, which may help control the glass properties

Researchers from the Osaka Metropolitan University Graduate School of Engineering have successfully developed a new technique allowing them to observe gas molecules packing into metal-organic frameworks (MOF) using infrared spectroscopy. Their innovation was to measure polarized light absorption of guest molecules in a MOF film to deduce molecule alignment using this common piece of lab equipment. This method is the first to show guest alignment and does so in real-time, while using an accessible and easily adoptable experimental setup. A short video (4 min) recreating their spectrometer modifications can be found in the Reference section.

Scientists developed a procedure to reproduce the double peak feature of x-ray emission spectroscopy (XES) spectra in liquid water.

Researchers at Kanazawa University report in Proceedings of the National Academy of Sciences how a protein molecular motor can chop off a piece of cell membrane. The constrict-and-cut mechanism resembles that of a ratchet motor, and is of importance in processes mediating the entry of particles into cells.

Osaka Prefecture University develops a method to design and control the path of electron flow in a polycrystalline material. Using epitaxial growth approach, researchers address the electrical conductivity problem of thin film materials by realizing a highly conductive in-plane orientation of a metal-organic framework. Furthermore, they show that it is possible to fabricate oriented thin film patterns by integration with UV lithography technology.

Researchers at Osaka Prefecture University have established an approach to identify the orientation of molecules and chemical bonds in crystalline organic-inorganic hybrid thin films deposited on substrates using Fourier transform infrared spectroscopy (FT-IR) and polarized infrared light with a 3D-printed attenuated total reflectance (ATR) unit. This inexpensive method with laboratory-grade equipment quickly reaches the crystal-structure model of even extremely thin films of less than 10 nm.

Chemical rings of carbon and hydrogen atoms curve to form relatively stable structures capable of conducting electricity and more — but how do these curved systems change when new components are introduced? Researchers based in Japan found that, with just a few sub-atomic additions, the properties can pivot to vary system states and behaviors, as demonstrated through a new synthesized chemical compound.

Researchers at The University of Tokyo discover a new law about how the complex network of phase-separated structures grows with time, which may lead to more efficient batteries and industrial catalysts

Researchers at Osaka City University use quantum superposition states and Bayesian inference to create a quantum algorithm, easily executable on quantum computers, that accurately and directly calculates energy differences between the electronic ground and excited spin states of molecular systems in polynomial time.

Scientists at The University of Tokyo use a two-state model based on the formation of tetrahedral structures to explain water’s anomalous properties and the surprising liquid–liquid transition of water.

A hemispherical vanadium oxide cluster has a cavity that can accommodate a bromine molecule. It was found that a bromine molecule trapped in the cavity was polarized and that an alkane molecule like pentane, butane and propane could be brominated with the bromine molecule in the cavity with a selectivity differing from ordinary bromination. The present findings are expected to be useful for polarization of small molecules and design of highly functional catalysts.

Professor Tetsuo Endoh, leading a group of researchers at Tohoku University, has announced the development of an MTJ (Magnetic Tunnel Junction) with 10 ns high-speed write operation, sufficient endurance (>10¹¹), and with highly reliable data retention over 10 years at 1X nm size. Realizing a 1X nm STT-MRAM (Spin Transfer Torque-Magnetoresistive Random Access Memory) and NV(Non-Volatile)-Logic has wide application to a variety of fields.

Researchers at Nagoya University, Japan, have developed a spontaneous polymer network synthesis that allowed for the preparation of gels containing narrow molecular weight distribution polymers. The gel networks showed swelling properties that were responsive to temperature and solvent concentration.