Research and Fabrication of Integrated bio-sensor for blood analysis based on μTAS

摘要

For simultaneously detecting multi-parameters of blood in the clinical diagnosis, the analysis apparatus should be smaller in size, more reliable and sensitive. So a kind of integrated bio-sensor for blood analysis based on Micro Total Analysis System (μTAS) is presented. It provieds modern bio-sensor prospect with a novel technology. A multi-parameters of blood analysis integration sensor is μTAS bio-sensor based on 4 groups of interdigital array ( IDA ) microelectrodes. The IDA microelectrodes are fabricated on glass substrates by photography, film deposition and other microfabrication techniques. Thin-film gold microelectrode with a thickness of 250nm is deposited on a chromium-adhesion layer. The finger microelectrode width and space are both 10μm. The work space is 2×2cm~2. The concentration of Blood sugar , Total Cholesterol , Acetone body and Lactic acid is measured by detecting eady-state limiting currents in IDA microelectrodes modified with enzymes on the "generate-collect" mode. Blood distribution structure is designed and fabricated, to distribute blood and isolate reaction areas. By contrasting two kinds of process flow based on lift-off and etching, etching is adopted to preparation method of microelectrode. A multi-channel apparatus for current measurement is accompleted. The system characteristics of the bio-sensor are tested. The curve of the apparatus time to current response is achieved by testing on real-time. The relationships between parameter concentration and current are analyzed in detail. The experimental data indicates: current measurement dimension 0 ～ 40 μA , certainty of measurement 0.1 μA , the performances of the bio-sensor meets design requirement.