Research On Measurement And Calibration Methods Of Temperature Field For PCR Instruments

PCR technology can quickly amplify the target gene or DNA fragment in vitro. It has developed into one of the common technologies for researchers to obtain DNA fragments, and it has been widely used in biomedical field.The temperature accuracy and uniformity of PCR sample block is an important factor influencing the PCR reaction. To measure the temperature uniformity and other temperature parameters of sample block, measurement tools are required to have more than one measurement channel, and to have excellent accuracy, speed of response, channel consistency and synchronization. This paper presents a multi-channel temperature measurement and calibration system. It can detect the temperature field of PCR sample block in real time, and analyze the temperature performance of each PCR instrument before giving the discrimination results of their temperature performances to realize the calibration of temperature Field. It is excellent to meet the special requirements of controlling the temperature field of PCR instruments.In this paper, the temperature measurement requirements of PCR instruments and common temperature measurement methods were studied. With the analysis of selection methods of temperature sensor and temperature measurement points, a multi-channel temperature measurement system was designed and established. The temperature acquisition and processing software programming were conducted based on programming characteristics of the data acquisition system, and through implementing real-time temperature acquisition and processing of the 13 measurement points, a thermal model of indirect temperature measurement was established, to detect the relative lag time between the temperatures of agent and reaction well, as well as the relationship between these two temperatures at the same time. In addition, the system performance was analyzed experimentally. Test results showed that the system had high precision, consistency, and anti-interference ability, and the overall performance of which met the basic requirements of practical application. Advices to improving the performance of this system and plans of future work are given at the end of this paper.