| In the present work, the investigation on the biosensor chip with Chemiluminescence detection and novel Chemiluminescence systems is reported in part I and II, respectively.Part I. In this section, two biosensor chips coupled to microfluidic analysis system with Chemiluminescence detection are developed for the determination of clinically important biochemical substances including uric acid and glucose in serum. In general, for all the assays on chip with micromechanical pumping devices, the carrier solution was required. In the present work, we took the air as the carrier flow instead of solution on a biosensor for the first time. The distinguished possible advantages of this microfluidic system based on carrier airflow 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 affected the sensitivity. Especially in the present microfulidic system, the chemical background which was usually inevitable because of the carrier solution, would be eliminated by using air as the carrier flow, thus a large signal to noise ratio (SNR) and a large 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 eliminate and often affected 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 (obviously, the case in which the carrier solution was the reaction reagents was not included). However, when the air was used as the carrier flow instead of the solution, the phenomenon of spreading disappeared, and a great sensitivity could be attained. This part is divided into four chapters. Chapter 1 reviews the development of the biosensor and biosensorchip in recent years.In chapter 2, a chemiluminescence biosensor on a chip coupled to microfluidic analysis system and microreactor is described. The chemiluminescence biosensor measured 25+75+6.5mm in dimension, and was readily produced in analytical laboratory. The sol-gel method is introduced to co-immobilize horseradish peroxidase (HRP) and luminol in the microreactor, and to immobilize uricase in the enzymatic reactor. The main characteristic of the biosensor was to introduce the air as the carrier flow instead of the common solution carrier for the first time. The uric acid was sensed by the CL reaction between hydrogen peroxide produced from the enzymatic reactor and luminol under the catalysis of HRP in the microreactor. The present biosensor chip was successfully applied to the measurements of uric acid in serum. Under the optimum conditions, the response to the uric acid concentration was linear over range1.0 to 100 mg.L-1 with a regression equation of I=3.09C (mg.L-1) + 2.1 (r2=0.9992, n=6) and a detection limit of 0.1 mg.L-1(3). The relative standard deviation for 50 mg.L-1 uric acid was 4.2% (n=7). After the enzymatic reactor was hermetically stored at 4C for 10 days, no significant changes were observed in response characteristics of the system. More than 200 measurements were carried out during this time. The proposed biosensor chip was successfully applied to the measurement of uric acid in human serum.In chapter 3, a chemiluminescence biosensor on a chip coupled to microfluidic system is described in this paper. The chemiluminescence biosensor measured 25+45+5mm in dimension, was readily produced in analytical laboratory. Glucose oxidase (GOD) was immobilized onto controlled-pore glass (CPG) via glutaraldehyde activation and packed into a reservior. 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 instead...
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