In this paper, newly application of the absorptiometry microchip was considered and sensor property was characterized with real sample. C-reactive protein (CRP) measurement, that is one of the items of serology test, was chosen as first application. CRP value is very useful marker of irritation and also appropriate to confirm ability of sensor performance for Particle-Enhanced Turbidimetric Immunoassay (PETIA). Fabricated microchip shows characteristics equivalent to commercially available sensor unit. Sensor property with different concentration samples was also evaluated. Temperature effect for PETIA was described with characterized data. From the results of characterization and discussion, the microchip can be applicable for CRP measurement with PETIA.

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We have proposed and demonstrated a technology for CMOS photosensor / image sensor that will be implemented onto μTAS. Polarization-analyzing CMOS sensor was realized with an idea of monolithically-embedded on-chip polarizer. The on-chip polarizer was configured with a metal wiring layer in standard CMOS fabrication technology. We describe concept, design of a polarization-analyzing CMOS photosensor array and a polarization-analyzing CMOS image sensor. We characterized performances of the fabricated sensors and confirmed that the proposed technology is feasible CMOS-based on-chip polarization analysis. We also successfully demonstrated polarimetric measurements of chiral solutions using the fabricated sensors.

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In this paper, we report the detection of transporting function at cell membrane using capacitance-voltage (CV) measurement. The detection principle of our devices is based on the field-effect of electrostatic interaction between charged species at cell membrane in solution and surface electrons in silicon crystal through the gate insulator of Si₃N₄/SiO₂ thin double-layer. We designed an oocyte-based field-effect capacitor, on which a Xenopus laevis oocyte was fixed. The transporter of human organic anion transporting peptide C (hOATP-C) was expressed at oocyte membrane by induction of cRNA. The electrical phenomena such as ion or molecular charge flux at the interface between cell membrane and gate surface could be detected as the change of flat band voltage in CV characteristics. The flat band voltage shift decreased with incubation time after introduction of substrate into the oocyte-based field-effect capacitor. The electrical signal is due to the change of charge flux from the oocyte at the gate surface inspired by transporter-substrate binding. The platform based on the oocyte-based field-effect capacitor is suitable for a simple and non-invasive detection system in order to analyze function of transporters related to drug efficacy.

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Embryo handling is an extremely important fundamental technique in reproductive technology and other related life science discipline. The handling usually requires an artisanal operation that uses a glass-made capillary tube to suck in / out the embryo by applying external pressure with mouth or pipetting, to move it one to another environment and to redeliver into the womb. Because of the delicate operations, it is difficult to obtain quantitative result through the experiments. It is therefore an automatic embryo handling system has been highly desired to obtain stable quantitative results, and to reduce the stress for the operators. In this paper, we proposed and developed an automated embryo culture device, which can make an array of the embryos, culture them to be the blastocyst stage, and collect the blastocyst using the dynamic microarray format that we had studied previously. We preliminary examined the three functions of trapping, culture, and release using a mouse embryo as a sample. As a result, the mouse embryos are successfully trapped and released, whereas the efficiency of the in-device embryo culture was less comparable than the conventional dish culture. The culture stage still needs optimization for embryos, however the concept of embryo manipulation was proofed successfully.

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We developed a chip-based coculture system for cytotoxicity test, as our continuous effort to develop a multi-functional micro culture device realized by integration of fluidic control. The culture zone in the device was divided into two compartments separated by a microporous membrane through which substances in culture medium can freely come-and-go to induce the mutual interactions between the cells cultured at each compartment. In this work, it was examined that 1) coculture and 2) cytotoxicity model through oral intake, using Caco-2 and Hep G2 cell as a model cell of small intestine and liver respectively. As a result of test 1), Hep G2 cells cocultured with Caco-2 show same albumin secretion activity as the one not cocultured with Caco-2 cells. As a result of test 2), The cytotoxicity of caffeine and paraquat on Hep G2 cells was successfully measured with and without association of a selective chemical barrier function of Caco-2 cells.

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To develop the gas sensing devices using diamond films, time dependence of the surface resistance on the diamond film surrounded by oxidative gas has been investigated. After the termination of the diamond films surface by oxygen atom, the samples were annealed by hydrogen gas from 10 to 90 minutes (by 10 minutes step) under 900°C. The time depending changes in the surface resistance were measured in NO₂ gas and N₂ gas atmospheres. Following results were obtained. That is, in NO₂ gas atmosphere, transient time response of surface resistance of respectively annealed samples showed the almost identical time dependences. On the other hand, in N₂ gas atmosphere, samples were indicated no remarkable changes in annealing effect. To seek the situation concerned with the termination of annealed samples, the surface hydrogen densities per unit area were measured by ERDA (Elastic Recoil Detection Analysis). From these results, change mechanism of surface resistance due to annealing effect by hydrogen gas was discussed qualitatively.

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In this report, the ITO-ZnSe-CdTe cell and the ITO-ZnSe-CdTe-ZnTe cell as a photo sensor were analyzed comparatively with the use of the electric field analysis from spectral sensitivity data. From analysis, it is presumed that there is the depletion layer from the junction surface to 0.194μm in zone of CdTe layer at the ITO-ZnSe-CdTe cell. On the other hand, the ITO-ZnSe-CdTe-ZnTe cell has the depletion layer in whole region of CdTe layer. It is presumed that both ZnSe layer and ZnTe layer form the depletion layer of CdTe layer in the ITO-ZnSe-CdTe-ZnTe cell. The CdTe layer, which has 0.8μm in thickness, absorbs all of visible wavelengths, and both of two cells have CdTe layer 0.8μm in thickness. Luminous sensitivity of the ITO-ZnSe-CdTe cell is much less than luminous sensitivity of the ITO-ZnSe-CdTe-ZnTe cell. It is presumed that differences of the luminous sensitivity between those two cells arise from differences of the electric field distribution. From this analysis, it is presumed that the structure of ZnSe-CdTe-ZnTe makes depletion layer in whole region of CdTe layer.

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