This article has no abstract.

View full abstract

We developed new encapsulation method of glucose oxidase solution with ionic liquid solvent and direct Parylene deposition for the application to MEMS glucose sensors. Glucose oxidase has been immobilized in gel or polymer on MEMS sensors, but its weak mechanical property has been remained to be solved. Then, its encapsulation has been demanded, but high-temperature MEMS bonding process (>150 °C) for packaging the solution is destructive to glucose oxidase which is denatured over 50 °C. To solve these problems, we encapsulated the glucose oxidase-ionic liquid solution with room-temperature packaging (25 °C) of direct Parylene deposition process. The glucose oxidase solution array with the area of 1 × 3 mm² (approximately 1 μl) was patterned on the hydrophilic-hydrophobic surface modification on the MEMS electrochemical electrodes in the use of the wetting phenomenon of the solution and, then, packaged by the chemical vapor deposition of 1.5 μm Parylene. Parylene packages could be opened by pushing when used. The opened glucose oxidase solution reacted to 150 mM glucose solution, revealing the electrochemical potential of 150 mV. The sensitivity of our sensor ranged from 1 to 100 mM, which is the glucose concentration in the blood of the diabetic patients. Therefore, proposed encapsulation method exhibits the potential application to glucose sensor packages for diabetic patients.

View full abstract

With the objective of real-time monitoring of the structural integrity of man-made structures such as bridges, high buildings, and dams and areas of bedrock collapse and other such hazardous areas, we are attempting to use fiber Bragg grating (FBG) to construct a structural health monitoring system. To construct a multipoint strain measurement system with FBG, which is an optical fiber type sensor, we investigated ways to use FBGs that have the same reflection characteristics and FBGs that have different reflection wavelengths in multipoint measurement. The constructed system combines optical frequency sweeping with the multipoint FBG to accomplish measurement of the reflection wavelengths of multipoint FBG and real-time graphic display. This paper describes fundamental experiment on multipoint strain measurement, demonstrating that the constructed real-time measurement system can measure the reflection wavelengths of FBGs that have the same reflection characteristics and FBGs that have different reflection wavelengths every four seconds.

View full abstract

A micro-mirror array fabricated by MEMS process has been made for an electrostatic field distribution measurement system. Each micro-mirror is suspended by two thin torsion bars, which is made by using an SOI (Silicon on Insulator) wafer fabrication process. Deflection of each mirror by electrostatic field is measured optically by using a two dimensional optical scanner and a PSD (Position Sensitive Detector). The electrostatic field distribution measurement system was applied to a human body model.

View full abstract

This paper describes a wireless cardiography monitoring system for human healthcare. The system consists of a cardiography sensor module and a radio frequency (RF) module for data communication. And the P, Q, R, S, T signals was acquired by using the prototype cardiography sensor. Real-time cardiography monitoring was demonstrated with a RF base station which was located 10 m away from the sensing object.

View full abstract

This paper reports the development and performance of a detection system for magnetic beads. The system consists of a semiconductor based magneto-resistance sensor for beads detection and a lateral flow kit. Detection of anti-gen of H.Influenza at concentration of 0.1ng/ml was performed with satisfactory sensitivity, showing the system to be a promising for immunoassay.

View full abstract