Research and realization of algorithms for gene-chip PCR temperature-tracking control

In the bioengineering and biochemical research areas, the Polymerase Chain Reaction (PCR) is the prerequisite step for gene chips preparation. In the PCR reaction system, the temperature in the process of PCR thermal cycling must be very strictly controlled. Through analyzing the characteristics of the heating and cooling subsystems, the researchers in this project experimentally completed the control algorithms based on the conventional PID and predicative control strategies. In this PCR temperature control system, for the given temperature-time pattern curve, to conventional PID control algorithm, the temperature maximum overshoot is less than 3degC, the stable accuracy of temperature control is plusmn1degC, the maximum heating and cooling speeds are both 2degC/s. However, the experimental results demonstrated that the PCR thermal cycler based on predictive control algorithm has better temperature tracking capability, the maximum heating and cooling speeds are twice quick and the stable error is only one half as those of ordinary PID based PCR thermal cyclers and can meet the demands of control qualities for the PCR gene-chips preparation in some situations.