Article
Chemistry, Analytical
Kyojiro Morikawa, Haruki Kazumi, Yoshiyuki Tsuyama, Ryoichi Ohta, Takehiko Kitamori
Summary: This study confirmed the surface patterning of closed nanochannels using VUV light and successfully evaluated the surface using streaming-current measurements. The C-18 modification was verified through Laplace pressure measurements, and the decomposition of C-18 groups by VUV light led to a hydrophilic surface. The increase in current signals during streaming-current measurements indicated the successful patterning and surface evaluation in closed nanochannels.
Article
Chemistry, Multidisciplinary
Jose C. Mateus, Sean Weaver, Dirk van Swaay, Aline F. Renz, Julian Hengsteler, Paulo Aguiar, Janos Voeroes
Summary: This research utilizes electron beam lithography and photolithography to create microstructures that control neuronal connectivity, and demonstrates the formation of functional synapses in vitro.
Article
Nanoscience & Nanotechnology
Tuan A. Ho, Yifeng Wang
Summary: The study reveals that changes in gas pressure can lead to complex alterations in the wettability of solid surfaces involved in shale gas production and geological carbon sequestration, depending on surface chemistry, structure, and molecular interactions. Different solid surfaces exhibit varied responses to changes in CO2 gas pressure, playing a significant role in the design and optimization of related subsurface engineering processes.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Giovanni Di Muccio, Blasco Morozzo della Rocca, Mauro Chinappi
Summary: This study introduces a purely geometrical mechanism to induce ionic selectivity and electroosmotic flow in uncharged nanopores, and develops a theoretical model for designing pore geometry. The research shows that the selectivity depends on the applied voltage, and becomes completely inverted when reversing the voltage, leading to unidirectional electroosmotic flow.
Article
Chemistry, Multidisciplinary
Naiqing Zhang, Amihai Horesh, James Friend
Summary: Manipulation and mixing of fluids and colloids at the nanoscale is challenging due to the dominance of surface and viscous forces, but the use of megahertz (MHz)-order vibration in microfluidics has significantly advanced these capabilities. By discovering new regimes of acoustic wave interaction with small water droplets, manipulation and splitting of fluid droplets has been successfully achieved in fully transparent, high-aspect ratio nanoslit channels.
Article
Chemistry, Multidisciplinary
Yadong Wu, Yongchao Qian, Bo Niu, Jianjun Chen, Xiaofeng He, Linsen Yang, Xiang-Yu Kong, Yifei Zhao, Xiangbin Lin, Teng Zhou, Lei Jiang, Liping Wen
Summary: This study systematically explores the surface charge-regulated asymmetric ion transport behavior in nanoconfined space and its influence on nanofluidic energy conversion system performance. Improving the local apparent surface charge or introducing a selective layer with dense surface charge on the low concentration side can effectively enhance ion-selectivity and energy conversion performance. This material design concept is supported by both simulation and experiment, providing significant insights for ion behaviors in nanoconfined space and the development of high-performance energy storage and conversion systems.
Article
Electrochemistry
Sokhna Mery Ngom, Isabelle Le Potier, Anne-Marie Haghiri-Gosnet, Jean Gamby
Summary: The aim of this study is to gain a better understanding of conductance changes in nanoslit integrated in a microchip device, by conducting experiments and modeling in hybrid micro nano microchannels. Three models were discussed to analyze the factors influencing conductance, leading to the discovery of a micromolar concentration zone where the inverse Duhkin number reaches minimum values, highlighting the importance of nanoslits in electro-preconcentration protocol.
ELECTROCHIMICA ACTA
(2021)
Article
Physics, Multidisciplinary
Subhomoy Das, Alexander Butenko, Yitzhak Mastai, Moshe Deutsch, Eli Sloutskin
Summary: This study demonstrates temperature-controlled self-assembly of surface-adsorbed fluorescent molecules on water-suspended spherical oil droplets. Well-defined and highly ordered patterns are induced by self-positioned structural defects in a crystalline monolayer covering the droplets' surfaces. The findings provide insights into interfacial freezing effect on curved surfaces and enable precise positioning and self-assembly of functional ligands on droplets.
Article
Chemistry, Analytical
Kyojiro Morikawa, Ryoichi Ohta, Kazuma Mawatari, Takehiko Kitamori
Summary: This study investigated the use of nanochannels with functionalized surfaces in nanofluidics as a new tool for studying chemical reaction fields. By developing metal-free fabrication processes, nanochannels with widths and depths of 1000 nm were successfully fabricated without contamination from chromium. This research makes a significant contribution to the fundamental technologies employed in microfluidics and nanofluidics.
Article
Nanoscience & Nanotechnology
Anni Shi, Anamika Singh, Laura O. Williams, Juan C. Arango, Shelley A. Claridge
Summary: Most high-resolution interfacial patterning approaches are limited to crystalline inorganic interfaces. This study explores a method to generate high-resolution functional patterns on soft materials by photopolymerizing highly structured functional alkyldiacetylene patterns on a hard crystalline surface and then transferring them covalently to the soft material. The authors develop a probabilistic model to describe the polymerization and transfer process.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Yuanyuan Luo, Liqiong Niu, Pengyan Hao, Xiaoya Sun, Yongxi Zhao, Na Wu
Summary: This study presents a controllable tannic acid (TA) nanopatterning strategy based on DNA origami templates. The protruding clustered ssDNA on the DNA origami tiles serves as an index for the selective deposition of TA, allowing for controllable erasing and rewriting of TA nanopatterns. Furthermore, the TA polymers modified on the edges of the origami tiles enable reversible association/disassociation of origami multimers.
Article
Chemistry, Physical
Jeong-Won Lee, Kihwan Kim, Giwon Ryoo, Jisu Kim, Jeyaraj Vinoth Kumar, Woonbong Hwang
Summary: A new SHPo/SHPi patterning method for three-dimensional objects using aluminum was proposed in this study, achieving successful realization of patterned surfaces with contact angles of 10 degrees for SHPi surface and 160 degrees for SHPo surface. This method enables patterning even in areas that laser light cannot reach, expanding the application scope of SHPo/SHPi surface patterning technique.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Yuduo Guan, Bin Ai, Zengyao Wang, Chong Chen, Wei Zhang, Yu Wang, Gang Zhang
Summary: Plasmonic nanochemistry is utilized to develop a chemical patterning technique for multiscale distributed plasmonic nanoparticle arrays, allowing for precise control and application in various fields.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Physics, Applied
Bin Liu, Yun Yao, Qiang Li, Panpan Lan, Yun Fan, Wenxian Li
Summary: This study investigates the impact of salt type and concentration on the structure and dynamics of water molecules and ions at silica surfaces using molecular dynamics simulations. The results show that ion hydration affects the weak interaction in the solution and the diffusion rate of particles.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Multidisciplinary Sciences
Aisha M. Alqahtani, Zeeshan, Waris Khan, Hamiden Abd El-Wahed Amina, Somayah Abdualziz Alhabeeb, Hamiden Abd El-Wahed Khalifa
Summary: Micro polar fluids have a wide range of applications and studying their heat transfer properties in magnetohydrodynamic free convection movement is important. The findings of this study show that the velocity decreases and the micro rotation field increases with increasing micro rotation parameter. Additionally, the distribution of temperature is affected by factors such as Eckert number, curvature parameter, and magnetic factor.
Article
Engineering, Electrical & Electronic
Kyojiro Morikawa, Shin-ichi Murata, Yutaka Kazoe, Kazuma Mawatari, Takehiko Kitamori
Summary: In this study, a method for handling low-surface-tension liquids in micro-nanofluidic devices was developed using a Laplace valve. The proposed valve demonstrated precise fluidic control and showed potential for application in single-cell analysis devices. This research contributes to the advancement of fluidic control technologies in micro- and nanofluidic devices.
JOURNAL OF MICROMECHANICS AND MICROENGINEERING
(2022)
Article
Biochemical Research Methods
Koki Yamamoto, Kyojiro Morikawa, Hisashi Shimizu, Hiroki Sano, Yutaka Kazoe, Takehiko Kitamori
Summary: Single cell analyses are crucial for understanding cellular heterogeneity. This article presents a method for analyzing single cell proteomics using liquid chromatography mass spectrometry (LC-MS) and introduces an integrated nanofluidic device to perform high-throughput analysis and prevent analyte loss.
Article
Engineering, Electrical & Electronic
Hiroki Sano, Yutaka Kazoe, Kyojiro Morikawa, Takehiko Kitamori
Summary: This research presents a method for fabricating nanoscale curved structures for switch and partition operations. By utilizing a valve with a curved structure, solute leakage can be significantly reduced and response time can be improved, contributing to the realization of versatile nanofluidic analytical devices.
JOURNAL OF MICROMECHANICS AND MICROENGINEERING
(2022)
Article
Chemistry, Physical
Jun Shirai, Koji Yoshida, Hiroki Koreeda, Takehiko Kitamori, Toshio Yamaguchi, Kazuma Mawatari
Summary: The study investigated the microscopic water structure confined in 100 nm nanofluidic channels using nano X-ray diffractometry and Raman spectroscopy. It revealed a small change in the radial distribution function (RDF) due to the confinement effect of water, suggesting stronger hydrogen-bonding network and higher density for water in nanochannels. This information is significant for understanding liquid property changes and water structure in 10-100 nm spaces found in various chemical and biological systems.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Chemistry, Analytical
Yuto Takagi, Yutaka Kazoe, Kyojiro Morikawa, Takehiko Kitamori
Summary: This study developed a mass spectrometry (MS) interface utilizing nanofluidics to achieve high-sensitivity detection. By converting liquid samples into fL droplets through a nanofluidic device and controlling their trajectory, the droplets were injected into a mass spectrometer with 100% efficiency. A heat transfer module was also utilized to vaporize the droplets into gas-phase ions. Compared to a conventional MS interface, this interface achieved 290-fold higher detection limit for caffeine ions, resulting in 2 orders of magnitude higher sensitivity.
ANALYTICAL CHEMISTRY
(2022)
Article
Biochemical Research Methods
Takashi Saruko, Kyojiro Morikawa, Takehiko Kitamori, Kazuma Mawatari
Summary: An in vitro analytical platform for biological systems was established, with nanochannels serving as a model for biological confinement. Proton conduction was enhanced for channel widths less than 330 nm, and a large confinement effect was observed.
Article
Physics, Applied
Hisashi Shimizu, Chihchen Chen, Yoshiyuki Tsuyama, Takehiko Tsukahara, Takehiko Kitamori
Summary: Photothermal spectroscopy, coupled with micro/nanofluidic devices, is a reliable and nondestructive method for analyzing microscale objects. This review focuses on the historical development of thermal lens microscopes and summarizes their recent applications in separation, particle, biomedical, energy, and environmental analyses. Future perspectives in nanoscale liquid science, system integration, and biological studies are also discussed.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Yoshiyuki Tsuyama, Kazuma Mawatari
Summary: Detection and classification of nanoparticles at a single particle resolution have become crucial in the fields of materials chemistry, life science, and nanotechnology. This study presents the development of nanofluidic optical diffraction interferometry (NODI) for sensitive detection and classification of nanoparticles. The method utilizes optical diffraction by a single nanochannel as a reference light for interferometric light scattering detection, allowing for accurate measurement and discrimination of different nanoparticles.
MICROFLUIDICS AND NANOFLUIDICS
(2022)
Article
Chemistry, Analytical
Koki Yamamoto, Kyojiro Morikawa, Hiroyuki Imanaka, Koreyoshi Imamura, Takehiko Kitamori
Summary: Nanostructures can achieve highly efficient reactions, but the mechanism of accelerating enzyme reactions in a nanospace is still unknown. This study investigated the kinetic parameters of immobilized enzymes in micro- and nanochannels using nanofabrication, partial enzyme patterning, fluidic control, and a high sensitivity detection system.
ANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Analytical
Adelina Smirnova, Ryoichi Ohta, Emi Mori, Hisashi Shimizu, Kyojiro Morikawa, Takehiko Kitamori
Summary: We developed a process for enzyme-linked immunosorbent assay on a glass microchip using a thin-layered microfluidic channel. The channel has a high aspect ratio and an antibody layer immobilized directly on its surface. This method provides a large-volume capacity and high detection sensitivity. The developed immunosensor is reusable, requires a small sample volume, and provides fast analysis, making it promising for point-of-care biomedical applications.
ANALYTICAL METHODS
(2023)
Article
Biochemical Research Methods
Hiroki Sano, Yutaka Kazoe, Ryoichi Ohta, Hisashi Shimizu, Kyojiro Morikawa, Takehiko Kitamori
Summary: In this study, a nanofluidic analytical system integrated with multiple nanochannel open/close valves was developed. The system successfully accomplished fluid operations such as sample injection, pL-level aliquot sampling, and flow switching by opening/closing specific valves. The study is expected to significantly improve the usability of nanofluidic analytical devices and enable the realization of complex analytical techniques such as single-cell proteomics.
Article
Engineering, Electrical & Electronic
Kyojiro Morikawa, Po-yin Chen, Hai Linh Tran, Yutaka Kazoe, Chihchen Chen, Takehiko Kitamori
Summary: Channel fabrication technology is essential for microfluidic and nanofluidic devices. Glass channels are attractive due to their stability, transparency, and ease of modification. This study developed a microchannel fabrication method with high etching selectivity and smooth surface.
JOURNAL OF MICROMECHANICS AND MICROENGINEERING
(2023)
Article
Biochemical Research Methods
Qiushi Kang, Chenxi Wang, Kaimeng Liu, Takehiko Kitamori
Summary: In this study, a low-temperature direct bonding technology for nanofluidic devices was developed. It allows glass chips to be bonded at room temperature and channels to be modified prior to bonding using polytetrafluoroethylene (PTFE)-assisted plasma modification. This technology eliminates the need for heating and avoids component denaturation during the bonding process.
Article
Chemistry, Analytical
Yutaka Kazoe, Sho Kubori, Kyojiro Morikawa, Kazuma Mawatari, Takehiko Kitamori
Summary: With the development of analytical devices in nanofluidics, estimation of flow rate in nanochannels is crucial for calculating volumes in chemical processing. A mass flowmetry system was developed in this study to measure the flow rate of water in a fused-silica nanochannel. The study revealed that the flow rate is significantly affected by viscosity in a square nanochannel and slightly affected in a plate nanochannel, due to dominant surface effects.
ANALYTICAL SCIENCES
(2022)
