微小流体デバイスと半導体イオンセンサによる高精度pH測定法の開発

抄録

pH is an essential parameter which express acidity or alkalinity, and the values are used in many fields such as basic sciences, medicine, and chemical industries. The pH values have been measured by the glass electrode method, however the operator suffers from the slow response and instability of the electrode. In contrast, ion-sensitive field-effect transistor (ISFET) is a semiconductor-based sensor device, and it has advantages such as small size and quick response to the solutions with low buffering capacities. For the handling of the solution, we employed the microfluidic technology, and ISFET sensor was inserted into its small channel. We have obtained quick response and successfully measured pH values. The present device showed high-linearity with the correlation factor of 0.9992 from the calibration curve. The measurement error of the 10 kinds of sample solutions with high and low-buffering capacities were -0.0690 ± 0.1556, and the response time was within 2 sec.