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.