Fluidic micro electro mechanical system (fluidic MEMS) devices, composed of a micro pump, mixer, valve, reactor, sensor and an electric circuit on a chip, have been widely applied in biotechnology and medical analyses. This study describes the design and fabrication of a fluidic MEMS device that can separate living leukocyte cells from a single droplet of blood (< 1μl). The chip was constructed from two substrate materials sandwiched together to form a gap with an upper hydrophilic (glass) surface and a lower hydrophobic (acrylic resin) surface. A blood sample was flowed into the gap (40μm) between the two substrates driven by the difference in surface tension of the two materials. Leukocyte cells were left adhered to the lower hydrophobic surface, whereas red corpuscles flowed toward the exit of the fluidic MEMS device. The separation rate of the red corpuscles has been achieved to 91 ± 9% in a unit area of 0.1 mm². Further, the change in an area of a living leukocyte cell separated in the chip, was quantitatively analyzed. This study proposes a method for separating and measuring living cells in a fluidic MEMS device.

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In this paper, the limit size of a magnetic micro - machine using the magnetic torque was examined. This machine rotates according to a magnetic torque and is promoted. The limit of the miniaturization of the machine was examined by requesting the relation between a magnetic torque and the load torque. In the case of the rotating and driving magnetic micro-machine, the driving force and the drag decrease at the same rate. Therefore, the magnetic micro-machine can swim even if the machine becomes miniaturization.

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Aging goes on rapidly in Japan and traffic accidents of elderly driver are increasing year by year. It is a main cause of the accidents that most elderly drivers are not aware of the reduction in their visual performances. The purpose of this research is to develop the system that measures the elderly visual perceptions necessary for safe driving and improves their perceptions by education and training. This paper describes the simulator for measuring the most important visual perceptions; visual field, dynamic visual acuity and depth perception while driving. This paper also presents the measurement results of the visual perceptions for older drivers.

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In this paper we propose non-photolithographic fabrication processes of micro-fluid channels with patterned SAMs (Self-Assembled-Monolayers). SAMs with a thiol group are micro-contact printed on a patterned Au/Ti layer, which is vapor-deposited through a shadow mask. Ti is an adhesion layer. Subsequently, the micro-channels are formed by bonding surface-activated PDMS onto the silicon substrate via a silanol group, producing a SAMs-functioned bottom wall of the micro-channel. No photolithographic processes are necessary and thus, the proposed processes are very simple, quick and low cost. The micro-reactors can have various functions associated with the micro-contact-printed SAMs. We demonstrate successful manufacturing of micro-reactors with two types of SAMs. The micro-reactor with patterned AUT (11-amino-1-undecanethiol) successfully trapped nano-particles with a carboxylic acid group, indicating that micro-contact-printed SAMs remain active after the manufacturing processes of the micro-reactor. AUT -functioned micro-channels are applicable to bioassay and to immobilize proteins for DNA arrays. ODT (1-octadecanethiol) makes surfaces hydrophobic with the methyl terminal group. When water was introduced into the micro-reactor with ODT-patterned surfaces, water droplets remained only in the hydrophilic areas where ODT was not patterned. ODT -functioned micro-channels are applicable to fluid handling.

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This paper reports on a new PC mouse device by the use of the micromachined thermal flow sensors. The proposed mouse contains two small flow sensors mounted in two 10-mm-diameter and 3-mm-depth spaces in order to measure its velocity and direction. When the mouse is moved to a direction, air flow is generated because the air tends to stay where it is. Our sensors can detect the wide range flow speed which enables the mouse speed ranging from hundreds to one mm/s. The present flow mouse is as small as an optical one and it can work even on a smooth transparent glass. The results indicate that displacement can be measured with in an error ratio ±2% at 10, 50, 100 and 150 mm/s. This error ratio is good enough for this application.

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This paper outlines the development of a new primary calibration system for vibration and acceleration standard extending to the frequency range up to 10 kHz at the National Metrology Institute of Japan (NMIJ). In order to achieve this purpose, two types of laser interferometer with multifold optical path (twofold and fourfold optical paths) are discussed as measurement technique for quite small dynamic displacement down to 25 nm. These laser interferometers are successfully installed into the primary calibration system for the sine-approximation method in compliance with ISO-16063-11. The primary calibration system with the laser interferometer with multifold optical path are capable of performing practical calibration within maximum expanded uncertainty of 3.5 % in a higher frequency range up to 10 kHz.

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In this study, we report the sensitive detection of aromatic nitro compounds using a surface plasmon resonance (SPR) immunosensor based on the indirect competitive method. The vapors from the substances were sampled with a preconcentrator developed here. The solutions of the sampled vapors were measured using SPR immunosensor. Three kinds of explosives such as 2,4-dinitrobenzene, 2,4-dinitrotoluene, and 2,4,6-trinitrotoluene were detected at 1 ppb. Sampling time at 1 l/min was 3 min. Total detection time was brought down to 5 min, which is relatively short for second scanning in landmine detection. Efforts are being made to integrate the SPR immunosensor and preconcentrator for rapid sensitive detection of nitro aromatic compounds under simulated field conditions.

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