| The thesis consists of three parts. Each part includes a review and a reseach report.The first review introduces the development of the Miniaturized Total Analysis System(u-TAS) and the microfluidic analytical systems, including microfabrication techniques and detection technologies of microfluidic chips. In this paper, we developed a novel chemiluminescence biosensor chip for determination of uric acid in human serum based on microfluidic system and microreactor using air as a carrier flow. On this chip, uric acid was injected into the enzymatic reactor in which the uricase had already been immobilized by sol-gel, produced H2O2 was carried through the microchannel by the carrier flow (air) to the microreactor in which the luminol and HRP had already immobilized by sol-gel, then produced a CL signal. The distinguished advantages of this microfluidic system based on carrier air flow were shown in the next.Firstly, in microanalysis and ultra microanalysis. the solution background that resulted from the chemical interference, would be the primary factor that effected the sensitivity. Especially in the present microfluidic system, the chemical background which was usually inevitable because of the carrier solution, would be eliminated by means of using air as the carrier flow, thus a great signal noise ratio (SNR) and a great sensitivity could be obtained. Secondly, when solution was used as carrier flow in microfluidic system, small air bubbles taking shape in the rough inner wall of the microchannels were difficult to be eliminated and often effected the stability and the repeatability. Fortunately, the air carrier could avoid that disadvantage.Finally, the mutual spreading between the sample zone and the carrier solution in Flow Injection Analysis (FIA), would always result in the sample zone's widening and reducing the sensitivity. However, when the air was used as the carrier flow instead of the solution, the phenomenon of spreading disappeared,and a great sensitivity was attained.It was obvious that the proposed analytical method of the air carrier in microfluidic system were not suitable for the spectrophotometric, electrochemical and fluorescence detection. However, when applied in chemiluminescence detection, the distinguished advantages of this method could be shown enough. This method has not been reported up to the present, and would be the important technique to increase the sensitivity of the microfluidic analysis system in the future.The chemiluminescence biosensor measured 25x75 x5mm in dimension, was readily produced using common aiguille in analytical laboratory. Under the selected conditions, the response to the uric acid concentration was linear over range 1 to 100 mg/L with a regression equation of 7=3.09C (mg/L) + 2.1 (r2=0.9992,n=6) and a detection limit of 0.1 mg/L (3a). The relative standard deviation for 50 mg/L uric acid was 4.2% (n=7).Glucose oxidase (GOD) was immobilized onto controlled-pore glass (CPG) via glutaraldehyde activation and packed into a channel. The analytical reagents, including luminol and ferricyanide, were electrostatically co-immobilized on an anion-exchange resin. The most characteristic of the biosensor was to introduce the air as the carrier flow in stead of the common solution carrier for the first. The glucose was sensed by the CL reaction between hydrogen peroxide produced from the enzymatic reaction and CL reagents, which were released from the anion-exchange resin. The proposed method has been successfully applied to the determination of glucose in human serum. The linear range of the glucose concentration was 1.1 to 110 mM and the detection limit was 0. ImM (3a).The second review is about the development of fiber optical sensors. A novel flow-injection chemiluminescence (CL) biosensor for determination of paracetamol is described in this paper. The analytical reagents, luminol and ferricyanide. were electrostatically coimmobilized on an anion-exchange resin column. The signal produced by the reaction between luminol and ferricyanide, wh...
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