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Microfluidic chips are already in biochemistry, medical tests, synthetic drug screening, environmental monitoring and other fields has been widely used. Microfluidic chip combines biotechnology and microelectronics processing technology and functionality into a variety of instruments in the laboratory for processing on the chip, with miniaturization, high detection efficiency, simple operation, the detection of low-cost, easy-integrated advantages. The current widespread use of microfluidic chip production material is a polymer material, but there are still issues such as non-specific adsorption. The study results showed that the polymer surface modified by its nature, can improve the polymer chip is more conducive to the actual analysis of biological samples. Thesis polymers chip analysis platform, through effective modification method of microfluidic chip channel surface modification and modified, successful biological molecules within the chip channel fixed, new research methods for biological analysis . First microfluidic chip processing methods, production of materials, detection technology and practical application of research progress, and stressed the necessity and importance of the microfluidic chip channel surface modification and modified; details the development of immunoassays, biosensors and proteomics, the main research content and applications; concluded the purpose and significance of the thesis. This thesis is divided into chapters, poly (methyl methacrylate) (PMMA) and poly (ethylene terephthalate) (PET) microfluidic chip as research subjects, respectively, with different surface modification methods, including poly ethylene imine derivative method, gold nanoparticles glue layer assembly method, alumina sol - gel method, S100B protein antibody, aptamer and trypsin effectively fixed in a microfluidic chip channel surface, and the development of a micro-flow control chip analysis, enzyme-linked immunosorbent technology platform the aptamer specific recognition protein quantitative analysis, and enzyme reactor for protein identification. The details are as follows: First, the aptamer-based microfluidic chip is used the biosensor analysis study in this work the aptamer (aptamer) is fixed to the inner surface of the gold nanoparticles modified PMMA microfluidic chip channel, Aptamers can be highly specific to identify the characteristics of the human thrombin protein screening out, thereby thrombin is captured on the surface of the chip, while the thrombin and then labeled with biotin two aptamer combination Finally, the nature of the biotin - avidin specific interaction, the alkaline phosphatase is fixed, alkaline phosphatase may be generated in the catalytic substrate sensitive electrochemical signal, so as to achieve the purpose of detecting the human thrombin protein. This method is combined with a microfluidic chip fast response, small sample consumption, high sensitivity, last measured thrombin protein detection limit can reach 1 pM, wide linear range, from 1pM-100pM, the thrombin protein detection method is used for the actual human serum samples with satisfactory results. Second, the microfluidic chip for the high sensitivity of the brain damage marker S100B protein analysis detected in the present work, we developed a microfluidic chip-based electrochemical immunoassay sensor for low concentrations of brain damage marker S100B analysis and detection. The use of polyethylene imine (PEI) amino modification of poly (methyl methacrylate) (PMMA), the surface of the chip channel, for S100B protein antibody fixed. PEI is a polymer having a rich aminofunctional, it is able to cover the introduction of the amino functional groups in the PMMA surface, it is widely used for protein and DNA immobilization. S100B protein antibody is fixed, by the specific reaction of the antigen - antibody, S100B and alkaline phosphatase-labeled secondary antibodies sequentially together, having a sandwich structure is formed within the channel of the microfluidic chip enzyme immunoassay system . At the end of the chip microchannel using a three-electrode electrochemical detection system records with alkaline phosphatase catalytic reduction current signal 4 - aminophenyl phosphate (PAPP) in order to detect the concentration of S100B protein, low detection limit To 0.1pgmL-1, and the linear range was 0.1pg mL-1-100pg mL-1. the entire incubation reaction process and the detection process is integrated in the microchip device, having the advantages of high sensitivity, specificity and short analysis time. Therefore, this method provides for the clinical immunology test a new versatile detection platform. , Alumina sol - gel modified microfluidic chip enzyme reactor for the enzymatic hydrolysis of low-abundance proteins identified in this work by hydrolysis of the ester bond of the surface of the material to produce active groups such as-OH,-COOH, and further through their and sol - gel condensation reaction, in the polyethylene terephthalate (PET) chips channel internal terephthalate constructed sol - gel network structure, to achieve the embedding of the trypsin fixed prepared A12O3 sol - gel modification the PET chip enzyme reactor, used for the detection of low abundance proteins. A12O3 sol - gel is fixed in the passage surface of the PET microfluidic chip, there is provided one having a hydrophilic and biocompatible interface for embedded immobilized trypsin. Limited because a large amount of trypsin in the small micro-channel, a trace amount of standard proteins can be within a few seconds to complete the enzymatic hydrolysis step in the enzyme reactor of the chip. Extracted from mouse liver cells in complex samples to assess the the A12O3 sol - the gel micro enzyme reactor enzymatic performance and feasibility of application to obtain a better result. Benefits of rapid enzymatic methods for identification of this protein is that the method is simple, easy to operate, proteomics is expected to be further used for fast, efficient, enzymatic hydrolysis and identification of complex protein samples online.
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