In this study, we propose a dynamic microarray device that can trap two adjacent different beads in one spot. By combining a pair of microfluidic channels, we can make an array of two different types of 100 μm-sized beads in a line. We expect that this method will be useful in the continuous observation of the interaction or molecular diffusion between the beads.

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High throughput cell assay is significantly important in drug screening, assessment of toxicity etc. Cell assay with a microchip is one of the candidates for high throughput cell assay. However, reported cell assay system with the microchip requires expensive apparatus for refluxing medium and investigation of optimum experimental condition for steady data. For an inexpensive, easy and high throughput cell assay, we introduce a new cell assay system combined with a culture chip and an assay chip made of poly(dimethyl siloxane). Cell culture chips enabled cell to proliferate along the microchannel without refluxing medium and permitted to prepare cell patterning easily. Also, assay chips formed concentration gradient inside the chip and allowed the cell assay with different concentrations of drug at the same time. Thus, our developed cell assay system can overcome the problems of the present cell assay and would promote the drug discovery, assessment of toxicity etc.

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In this study, we developed a cell-based microfluidic device, which is integrated micro-electrochemical sensors, for online measurement of cellular glucose consumption under perfusion culture. Glucose sensors are placed at inlet and outlet of a cell culture chamber. The cellular glucose consumption is measured by comparing concentrations of dissolved glucose in culture medium before and after contact with the cells. As result of our preliminary test, online measurement of the difference of glucose concentration by cells succeeded using the device. We believe that the cell-based microfluidic device can be applied to bio- and medical science.

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The Mems-ONE is well known software which simulates thermo-viscoelastic properties in the conduct of nanoimprinting. Assuming the glass materials to be viscoelastic body, the relaxation shear modulus was measured by the creep test, Williams-Landel-Ferry (WLF) equation is applied for expressing the temperature dependence of liquid viscosity. We compared experimental with analytic results used by Mems-ONE with the condition of fixed pressure and time. Thermo-viscoelastic properties of the glass materials were estimated using unidirectional compression creep test based on traditional thermo viscoelastic theory. Glass was Borosilicate Glass (D263, Schott). Glass imprinting was carried out on Glassy Carbon (GC) mold with line & space10 μm patterns fabricated by dicing saw. The machining accuracy is most important thing as the evaluation mold. The glass imprinting temperature consulted thermo-viscoelastic properties of the glass materials. The numerical simulation was carried out on the small portion of mold and glass. The constant value of WLF equation fitting in high temperature translates the master curve of D263 with a high degree of accuracy. It caused the accuracy improvement of analysis result. In addition, we confirm that WLF equation intended to resin can use to the glass imprinting.

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In this research, one-axis high sensitive and low power consumption inclination sensor has been developed. The electric resistance of fluid between two electrodes is used to realize the sensor. A cap was attached to PCB board on which three electrodes were patterned. And propylene carbonate was encapsulated in it. Equivalent circuit model of the sensor was modeled using AC impedance method. DC and AC voltage were applied to a semicircle electrode, the other electrode was grounded and the voltage of an arc electrode was measured. The AC sensitivity was six times higher than the DC sensitivity at V_dd=5V. The sensor can operate even at low AC voltage of 1V. In addition, custom driving and detection circuit were developed and evaluated for practical application.

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We have proposed and investigated the properties of five-photodiode light sensor (5PD light sensor) which is able to search and track the solar light in the sky. In the present paper, we have focused the estimation about the orientation and declination of the 5PD light sensor regarding the plane of the top photodiode. Those are defined by the rotation of the azimuth and the declination of the elevation at the rotated angle. The rotation and the declination are originated to compare the solar directions between the calculation of solar orbit and the measurement using tracking function of the 5PD light sensor. The derivation is shown, and the estimation is performed on a typical example.

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We propose a micro-dew condensation sensor equipped with a quartz tuning fork (QTF) coated with a polystyrene sphere self-assembled monolayer (PSSAM) for dew condensation prevention. Polystyrene spheres with diameters of 202 and 356 nm were used. A micro-dew condensation sensing experiment was performed at 25°C and 45% relative humidity. The inflection point of the frequency shift curve for the QTF sensor coated with a PSSAM shifted to a higher temperature than that of a bare QTF. This suggests that the modified sensor can serve as a sensor used to prevent dew condensation.

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