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Basic Theory And Key Technique Of Integrated Biochemical Low Voltage Electrophoresis System On Microchips

Posted on:2007-06-30Degree:DoctorType:Dissertation
Country:ChinaCandidate:Y XuFull Text:PDF
GTID:1118360185988129Subject:Instrument Science and Technology
Abstract/Summary:PDF Full Text Request
The Microfluidic microchip is the most importmant development of miniaturized total analytical system in the field of micro analytical instrument. As a branch of the development, the integrated electrophoresis microchip, with the characteristics of high performance, fast speed, low reagent comsumption and easy automation, is more and more frequently being employed in life science and other relevant fields and is becoming the focus in the research of microfluidic analytical system. The microfluidic analytical system with high integration, easy automation and convenient portability is being pursued by researchers all over the world.However, some difficulties still remain in microfluidic chip electrophoresis, such as high working voltage, separation of the large detecting system, inaccessible exterior connection, sophisticated fabricaton and so forth. This doctoral thesis develops on the basis of the proposed theory of, low voltage separate model and its controlling methodology. A theory of Moving Gradient Electric Field Electrophoresis on Microchip is porposed in this paper, and a low voltage separate model and its controlling methodology are discussed in detail as well. On this basis, an integrated bio-chemical low voltage electrophoresis microchip system is developed as a result. The overall structural design of the chip was optiumed by the simulation analysis of electric and fluidic in the microchannel on the chip. Operational parameters of sampling, separating and detecting process were also obtained and selected as a result. The concept of double detectors, high frequence connectless conductivity detector and photo-electric detector integrated on the designed chip were proposed. The circuit controlling methodology was put forword and discussed in detail. As a result, the controlling circuit was designed and produced, which was easy for using and controlling. Based on the SOI material, the MEMS fabricating process was proposed to make the low voltage micochip with electrode array. The integrating fabrication on the chip was successfully carried out, and the microchip with microchannels, controlling circuits and detectors was obtained. With the selecting amino acids sample system, electrophoresis on microchip was carried on the integrated microfluidic analytical system, and experimental results have shown that the system was effective and practical in use.The main investigations in this thesis are as the fellowing.①On the basis of a large amount reference and pervious work, the theory of Moving Gradient Electric Field Electrophoresis on Microchip and relative controlling methodology were presented. The concept of total design of the integrated low voltage CE chip was proposed.②The solid mode of the integrated low voltage CE chip was set up at first. Then, ANAS and ConvertorWare finite element software was applied to simulate the electric and fluidic fields in the icrochannel on the integrated low voltage CE chip. According to the simulation results, structural and operational parameters were optimized and selected.③The double detectors, high frequence connectless conductivity detector and photo-electric detector, were proposed to integrate at the end of the separating channel on the designed CE chip. In this thesis, the high frequence connectless conductivity detecting electrodes were fabricated on the silicon CE chip.④The circuit controlling methodology of low voltage CE separation and analysis was put forword and discribed in detail. On this basis, the controlling circuit was successfully designed and produced.⑤According to the charactors of SOI material, the MEMS fabrication process was proposed to produce the integrated low voltage CE chip. Compatibility between Silicon and PDME in processing and bonding was investigated. The integrated microchip sample with microchannels, controlling circuit,detecting system and information obtaining system was figured out.⑥Amino acids were selected as the sample to be applied in the experiments of the low voltage electrophoresis on the integrated microchip. The experimental results had shown that the integrated low voltage CE chip analytical systemand relative controlling methodology was effective and practical.The research work in this thesis was supported by National Nature and Science Fund and by Chongqing Nature and Science Fund.
Keywords/Search Tags:Theory of Moving Gradient Electric Field Electrophoresis on Microchip, Low Voltage Electrophoresis Microchip, SOC, SOI-MEMS, μ-TAS
PDF Full Text Request
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