Research And Implementation Of Convection PCR Microfluidic System

Molecule diagnostic techniques based on gene amplification have the features as following:high sensitivity, high specificity, mature technology, etc. Since it has the ability to detect the virus and disease to a minimum rate of misdiagnosis, it is widely used in the field of in vitro diagnostics. When PCR (Polymerase Chain Reaction) technique was invented since 1985, researchers constantly make efforts to reduce the reaction time and to reduce the complexity of the instrument and to simplify the experimental operation.This paper constructs a fluorescence quantitative PCR diagnostic method and system based on microfluidic capillary convection PCR principle. It can significantly reduce the time required for thermal cycling reaction because of the heat convection formed in the microfluidic capillary. It can reduce the complexity of the instrument by removing the external fluid drive system. And it can reduce the complexity and power consumption of temperature control system by removing repeated heating and cooling. It can achieve a rapid detect, and prevent contamination detection by designing a low-cost and high-sensitivity fluorescence detection method.This paper introduces the design of real-time fluorescence quantitative gene amplification system in principle, and then introduces the system, fluorescence detection and temperature control module design and implementation. In the instrument design part, a dual processor architecture has been used to enable independent operation of interactive features and system functions. In the fluorescence detection design part, a series of optical devices like fiber optics, lenses, filters and other optical devices have been used to design the optical structure based on fluorescence characteristics of test substance. Besides LED, photodiode and other devices have been used to design a low-cost, highly sensitive fluorescence detection of nucleic acids. In the temperature control system design part, Internal Model Control strategy has been quoted to achieve fast tuning of the temperature control parameters.This paper constructs a nucleic acid amplification detection system which is simple, low cost, fast and easy to use. And it will cost less than 30 minutes to complete nucleic acid amplification and detection. At last we verify the reliability, sensitivity and accuracy of this system through a series of experiment using H1N1 influenza virus.