Design of signal preamplifier circuit for fluorescence detection system in quantitative PCR instrument

摘要

Quantitative Polymerase Chain Reaction (qPCR) has revolutionized the detection of DNA and RNA. But the quantification results are susceptible to the effects of background noise and the intensity of detected fluorescent signals. Aiming at solving the above problem, this paper presents a signal preamplifier circuit which is compatible to the fluorescence detection system. In the entire process of genetic quantification, the signal preamplifier circuit plays a very important role in amplifying the subtle fluorescent signal and eliminating the noise in the meantime. Experiment results show that with the help of this amplifier, the qPCR instrument can have a better performance in detecting weak fluorescent signals and precise quantification.