【摘要】：1983年，聚合酶鏈式反應(yīng)（Polymerase Chain Reaction，PCR）由Kary B．Mullis博士發(fā)明。PCR技術(shù)是一項革命性的創(chuàng)新，它在生物醫(yī)學(xué)領(lǐng)域具有重要的作用。實時PCR通過在PCR反應(yīng)體系中加入熒光探針，利用熒光信號累積實時監(jiān)測整個PCR進程，最后通過標準曲線對未知模板進行分析。由于此項技術(shù)靈敏度高，準確性強，因此已廣泛應(yīng)用于生物醫(yī)學(xué)領(lǐng)域，如醫(yī)學(xué)診斷、食品安全、動物檢疫和遺傳學(xué)研究等。 本文旨在開發(fā)一套基于DSP的實時PCR儀溫度控制系統(tǒng)，論文工作主要包括硬件開發(fā)和系統(tǒng)底層程序開發(fā)兩個部分。 硬件主要包括：DSP主控電路、驅(qū)動電路、半導(dǎo)體加熱制冷片、Kapton加熱板以及溫度傳感電路。DSP主控電路則包括電源電路、時鐘電路、JTAG接口、復(fù)位電路、PWM波輸出管腳、A/D轉(zhuǎn)換電路和串行通信接口；驅(qū)動電路由光電隔離電路和H橋功率放大電路構(gòu)建而成；采用半導(dǎo)體加熱制冷片和Kapton加熱板分別對樣品池和熱蓋進行溫度控制；采用鉑熱電阻Pt100作為溫度傳感器，并設(shè)計了消除非線性誤差的電橋電路進行溫度探測。 系統(tǒng)底層程序主要包括：軟件初始化子程、A/D轉(zhuǎn)換子程、PID算法子程、PWM波輸出子程、串口通信子程和Flash程序的燒寫。 最后，對所研制的溫度控制系統(tǒng)進行了調(diào)試。實驗結(jié)果表明，，A/D轉(zhuǎn)換的相對誤差為0.16%；樣品池的升降溫速率為4℃/s，溫度控制精度為±0.25℃；Kapton加熱板的升溫速率為2.2℃/s，溫度控制精度為±0.3℃；電泳結(jié)果表明本系統(tǒng)滿足PCR反應(yīng)條件；溫度數(shù)據(jù)可通過串行通信接口以9600的波特率傳輸至上位機，并由上位機軟件繪制溫度曲線。所開發(fā)的溫度控制系統(tǒng)已經(jīng)歷長時間的持續(xù)測試，系統(tǒng)運行穩(wěn)定。
[Abstract]:In 1983, polymerase chain reaction (Polymerase Chain Reaction,PCR) was invented by Dr. Kary B.Mullis. PCR technology is a revolutionary innovation and plays an important role in biomedicine. By adding fluorescence probe into PCR reaction system, real-time PCR monitors the whole PCR process by fluorescence signal accumulation. Finally, the unknown template is analyzed by standard curve. Due to its high sensitivity and accuracy, it has been widely used in biomedical fields, such as medical diagnosis, food safety, animal quarantine and genetic research. The purpose of this paper is to develop a real time PCR temperature control system based on DSP. This paper mainly includes two parts: hardware development and system bottom program development. The hardware includes: DSP main control circuit, driving circuit, semiconductor heating chiller, Kapton heating board and temperature sensing circuit. DSP main control circuit includes power supply circuit, clock circuit, JTAG interface, reset circuit, PWM wave output pin, Ar / D conversion circuit and serial communication interface; The driving circuit is composed of optoelectronic isolation circuit and H-bridge power amplifier circuit, and the temperature of the sample cell and the hot cover are controlled by using the semiconductor heating chiller and the Kapton heating plate, respectively. The platinum thermal resistance (Pt100) is used as the temperature sensor, and a bridge circuit is designed to eliminate the nonlinear error to detect the temperature. The bottom program of the system mainly includes: software initialization sub-program, A / D conversion sub-procedure, PID algorithm sub-path, PWM wave output sub-path, serial communication sub-program and Flash program burning. Finally, the temperature control system is debugged. The experimental results show that the relative error of A- / D conversion is 0.16, the temperature control precision is 鹵0.25 鈩

本文編號：2398097