| Summary: | 博士 === 國立臺灣大學 === 化學工程學研究所 === 98 === The main purpose of this dissertation is to develop a highly selective biosensor and discuss its electrochemical properties.
First, the covalent enzyme immobilization method (in Chapter 3) was proposed to attach cholesterol oxidase (ChO) on poly(3-thiopheneacetic acid). Three different red-orange films were electropolymerized by applying 1.5 mA for different times. The best sensitivity (SEN) for cholesterol obtained is 4.49 mA M-1 cm-2 at 0.7 V (vs. Ag/AgCl/sat’d KCl) and the limit of detection (LOD) is 0.42 mM. The interferences, ascorbic acid (AA) and uric acid (UA), increased 5.2% and 10.3% of the original value, respectively. By another method (in Chapter 4) to immobilize enzyme, poly(3,4- ethylenedioxythiophene) (PEDOT) is used as a matrix for entrapping glucose oxidase (GOD) by the cyclic voltammetry (CV). The LOD and SEN on glucose for the biosensor are 0.13 mM and 12.42 mA cm-2 M-1, respectively. In the aspects of interferences on AA and UA, the sensing currents increased about 9.7 % and 39.1 %, respectively.
For lowering the interference further, the inter-digitated array microelectrodes (in Chapter 5) consist of two working electrodes (WE1 & WE2), in which WE1 was the enzyme-modified electrode immobilized by entrapment and WE2 was a platinum to oxidize the interference near the boundary layer before the stream reaching WE1. In the flow system, 0.7 V was applied on WE1 to detect H2O2. The SEN for glucose was 157
|
|---|
