Toru Futami

High-Density Dielectrophoretic Microwell Array for Detection, Capture, and Single-Cell Analysis of Rare Tumor Cells in Peripheral Blood.

Development of a reliable platform and workflow to detect and capture a small number of mutation-bearing circulating tumor cells (CTCs) from a blood sample is necessary for the development of noninvasive cancer diagnosis. In this preclinical study, we aimed to develop a capture system for molecular characterization of single CTCs based on high-density dielectrophoretic microwell array technology. Spike-in experiments using lung cancer cell lines were conducted. The microwell array was used to capture spiked cancer cells, and captured single cells were subjected to whole genome amplification followed by sequencing. A high detection rate (70.2%–90.0%) and excellent linear performance (R2 = 0.8189–0.9999) were noted between the observed and expected numbers of tumor cells. The detection rate was markedly higher than that obtained using the CellSearch system in a blinded manner, suggesting the superior sensitivity of our system in detecting EpCAM− tumor cells. Isolation of single captured tumor cells, followed by detection of EGFR mutations, was achieved using Sanger sequencing. Using a microwell array, we established an efficient and convenient platform for the capture and characterization of single CTCs. The results of a proof-of-principle preclinical study indicated that this platform has potential for the molecular characterization of captured CTCs from patients.

Energy loss near‐edge structure for materials containing light elements by reflection electron energy loss spectroscopy

A reflection electron energy loss spectroscopy system has been developed to investigate local surface atomic structures around light elements such as C, N, and O. Electrons scattered inelastically on a surface with a small scattering angle are energy analyzed. This system was used to measure energy loss near‐edge structures (ELNESs) for materials such as BN, graphite, and NiO. The comparison between ELNES and x‐ray absorption near edge structure suggests that the ELNES is useful for the atomic structure analyses of surfaces.

Mass-Production System of Nearly Monodisperse Diameter Gel Particles Using Droplets Formation in a Microchannel

We optimized the shape of single Y-junction microchannel and multichannel structure for oil-in-water droplet formation. And we confirmed the efficacy of mass-production system of nearly monodisperse diameter gel particles.

Feasibility of Reflection Electron Energy Loss Spectroscopy with a Small Scattering Angle for Research in Surface Science

A reflection electron energy loss spectroscopy (R-EELS) system has been developed to investigate local surface atomic structures around light atoms such as C, N, and O. In this system, the primary electrons are incident on a surface at a grazing angle, and the electrons scattered inelastically at a small scattering angle are energy-analyzed to make the momentum transfer from the primary electrons to the scattered ones as small as possible. With this system, one can measure an energy loss near edge structure (ELNES) and an extended energy loss fine structure (EXELFS), compared with an X-ray absorption near edge structure (XANES) and an extended X-ray absorption fine structure (EXAFS). The feasibility of the system in surface science is examined by measurements of ELNES and EXELFS for oxygen-adsorbed Ni(100) surfaces.