摘要
时间分辨荧光免疫分析仪的测量精度取决于其对弱荧光信号检测电路的抗噪声能力。实验针对光电倍增管的特点,设计的电流模放大电路克服了常用电压模放大电路的弊端,提高了检测电路的抗噪声能力;为克服光电倍增管阳极暗电流的影响,设计了暗电流自动补偿电路。测试结果显示,在同样增益下,电流模放大电路及暗电流补偿技术采集的荧光信号中所含噪声小于电压模放大电路采集的荧光信号中所含噪声。采用电流模放大电路和暗电流自动补偿技术可以显著地减小噪声,较大地提高信噪比。提示采用电流模放大和暗电流补偿技术的微弱荧光信号检测电路可以提高信号采集精度、灵敏度、稳定性和可靠性,从而改善时间分辨荧光免疫分析仪的整体性能,提高其检测极限和检测精度。
The accuracy of time-resolved fluorescence immunoassay （TRFIA） instrument depends on the anti-noise capacity of the measurement circuit for weak fluorescence signals. On the basis of the characteristics and performance of photoelectric magnification tube （PMT）, in order to improve the accuracy of detection circuit, current-mode amplifying circuit is designed to overcome the shortcomings of the voltage-mode amplifying circuit. Dark-current automatic compensation circuit is designed to overcome the influence of anode dark-current in PMT. The test results show that the fluorescence signals selected by current-mode amplifying circuit with dark-current automatic compensation technology contain less noise than the fluorescence signals selected by voltage-mode amplifying circuit. Therefore, the current-mode amplifying circuit and dark-current automatic compensation system can significantly reduce noise and greatly improve the signal to noise ratio. With the current-mode amplifying technology and dark-current automatic compensation system, the detection accuracy, sensitivity, stability and reliability of the detection circuit for weak fluorescence signals can be greatly improved. Thereby, the detection limit can be extended, and the performance and detection accuracy of TRFIA can be further improved.
出处
《中国组织工程研究与临床康复》
CAS
CSCD
北大核心
2009年第4期705-708,共4页
Journal of Clinical Rehabilitative Tissue Engineering Research
基金
上海市重点学科建设项目(B504)~~
