Ryoji Kurita

Bioanalytical Devices for Highly Selective Measurement of in Vivo Biochemicals

We developed microfluidic bioanalytical devices for the continuous measurement ofin vivo catecholamine. Our devices were integrated with a carbon-film based interdigitated array electrode and a nanoliter volume pre-reactor to eliminate such interferents as L-ascorbic acid in a thin flow channel. We also fabricated an IDA electrode whose line and gap were both several nanometers. The pre-reactor had a microstructure and was modified with enzyme. We succeeded in detecting 1 nM of dopamine, which is the basal level in blood, in the presence of 10000 times its concentration ofL-ascorbic acid.

Bioanalytical Devices for Highly Selective Measurement of Transmitters From Cultured Cells

Two types of devices for highly selective measurement of biomolecules were fabricated. One consists of a dual electrochemical flow channel for differential measurement of neurotransmitters. The other is integrated with micro-reactor having a number of micro-pillars that remove interferent effectively in the small volume.

Microfabricated Biosensors for Measuring Neurotransmitters from Cultured Nerve Cells

We developed an on-line sensor with a micro-machining technique for the real-time measurement of the excitatory neurotransmitter, L-glutamate, released from cultured rat nerve cells. The sensor was made by bonding two glass plates, together. One plate has a rectangular flow channel and the other has a carbon film based electrode deposited on it by chemical vapor deposition and pyrolysis. The electrode was modified with glutamate oxidase and mediator. The sensor was operated at a slow flow rate of 0.1 μl – 4 μl/min by drawing the solution near the target nerve cell with a syringe pump.