| Due to its low sample consumption, high resolution efficiency, miniaturization and portability, miniaturized total analysis system (μTAS) has become a hot focus in recent years. It has been widely applied in the fields of various biochemical analysis. Mixing process is essential and necessary for any chemical or biochemical reactions. However, the fluids in micro-scale conduits are laminar which increased the difficulty in efficiently mixing. What's more, with the reducing of the samples consumption, a higher request is needed for the sensitivity and response speed of the detector.Depending on chemical reaction of their own to produce light signals, chemiluminescence (CL) detection system is characterized by simply cheap optical systems requiring no light sources, which avoid the effects of stray light and the instability of the light source, and thus providing low background with excellent sensitivity. CL detection method is widely used in flow injection analysis (FIA) and microchip capillary electrophoresis (MCE). However, it has not been unsatisfactory for the sensitivity and repeatability of the microchip-based CL detection system so far. The reasons are as follows:first, the on-chip mixing of the analyte and CL reagent are not efficient; secondly, on-line introduction of one or two CL reagents into the system is always required for initiating the CL reaction in MCE systems. Owing to the channel network, the flows in different channels affect each other during the introduction of CL reagents.In the first chapter, the principle and general systems of CL, application of CL detection method in the microfluidic chips, mixing and driving of fluids in micro-scale conduits were reviewed.In the second chapter, a novel, rapid and sensitive microflow injection chemiluminescence (μFI-CL) system for the determination of cisplatin in pharmaceuticals and human serum was described based on platinum catalyzed luminol-hydrogen peroxide reaction in a basic aqueous solution. The effect of microchip configuration on mixing efficiency was investigated and the influences of pH of media, scale of the channels, concentration and flow rate of CL reagents on the detective sensitivity were also discussed.1,10-Phenanthroline was proposed as the masking agent to remove the interference from other metal ions coexisted in the samples. By using the microchip with double spiral channel configuration, the sensitivity was greatly enhanced due to larger mixing/detection area and efficient mixing of the analytes and reagent solutions. Under the optimized conditions, the absolute detection limit of 2.48×10-15mol for Pt2+could be achieved. The sample consumption was only 2.0μL and the sample throughput was 72 h-1In the third chapter, we present a compact and low-cost MCE-CL system. A novel interface was developed for coupling MCE and CL detection by creating a porous monolithic plug in the separation channel as a select valve, which hinder the pressure-driven flow through the separation channel but allows electrophoretic migration to take place. This arrangement can eliminate the negative effect of the pressure-driver flow on electrophoresis seperation in the seperation channel. Manipulation of both a rapid and variable-volume sample loading and CL reagents transportation were realized by a simple and low-cost subatmospheric pressure fluid-driven device. The suggested fluid-manipulation device is rather simple, only composed of a vacuum pump, a 3-way electromagnetic valve, a needle valve and a single high voltage supply. All miniaturized components are commercially available. In addition, the power consumption for CE separation is only 4W, which demonstrate it is an environmentally-friendly analytical device. It has been applied for the determination of metals content in human serum and tea samples after digestion. The results proved that the proposed MCE-CL system offers a number of benefits including miniaturization, high sensitivity and better resolution.In the forth chapter, monoliths prepared by in situ photopolymerization at the separation channel of the microchip were served as the solid phase of the microchip-based electrochromatography(μCEC). On the basis of the third chapter, negative pressure combined with electrokinetic force injection method has been utilized. We present a compactμCEC-CL system in which underivatized amino acids were direct analyzed. The amino acids were detected because of enhanced Cu2+catalytic activity for luminol-hydrogen peroxide CL. The Cu2+catalyst was more active when it interacted with biomolecules to form Cu2+-biomolecule complexes. Glycine(Gly), Glutamic acid(Glu), Arginine(Arg) and Aspartic acid(Asp) were chosen as model compounds to evaluate the performance of theμCEC-CL system. The results demonstrated that the proposed system offers a number of benefits including miniaturization, significant simplification in operation and instrumentation. What's more, it does not require a complex labeling procedure for amino acids.
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