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 provides 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 2×2cm2. The concentration
of Blood sugar, Total Cholesterol, Acetone body and Lactic acid is measured by detecting steady-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 0~40μA, certainty of measurement 0.1μA, the performances of the bio-sensor meets design requirement.
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