Research And Manufacture Of A Pyrosequencing-Based Gene Detection Device

Pyrosequencing technology is applicable for short sequence analysis, which has the potential advantages of accuracy, flexibility, parallel processing, and can be easily automated. Furthermore, the technique dispenses with the need for labeled primers, labeled nucleotides, and gel-electrophoresis, but the high price of pyrosequencing instrument encumbers its popularization and development. The objective of our research is to design a pyrosequencing-based gene detection device of low cost and simple structure and to offer a convenient sequencing platform.Based on liquid phase pyrosequencing, machine configuration and work flow of this sequencing device are designed. Device is divided into several function modules, low-light detection module and micro-scale solution delivery module are regard as the key of it.S1133-01 type photodiode is selected to be the photosensitive element. A light-electric conversion circuit with high sensitivity is designed. The Tina-Ti simulation software is used for the stability analysis of this circuit. The low limit of light-current detection for this circuit is 5.24×10^-15A (S/N=2). The 96-channel low-light detection module is made up of a 12×8 photodiode array. Measures such as input guard of operational amplifier, high surface insulation resistance PCB, transparent conductive film are utilized to strength the electromagnetism compatibility of low-light detection module, which effectively reduce the influence of environment interference.An air-pressure control micro-scale solution delivery system is designed whose minimal volume of delivery is 1.2μL with an error less than 13%.Prototype model of this gene detection device is finished, but it is necessary to take measures to reduce the exorbitant noise.