基于酶催化发光的便携式痕量cTnI分析仪研究

心肌肌钙蛋白I(cTnI)是一种诊断心肌梗死的金标准蛋白标志物。基于酶催化发光分析技术的原理,研制了一种便携式痕量cTnI分析仪。与现有检测系统不同,生物反应采用碱性磷酸酶的新型发光底物AMPPD,通过磁珠分离富集,使其发光背景低、信噪比高。光路设计采用共聚焦方式,光电倍增管做光电转换器件,通过密封在铝质暗箱中进行屏蔽,使分析仪不但易于集成、灵敏度高,而且具有良好的抗干扰能力。另外,仪器设计了自动加样单元,可以减少人为操作误差。实验表明,分析仪在cTnI浓度为0.03～30 ng/mL范围内具有良好的线性响应特性,相关系数R=0.99,达到痕量水平检测,对其进行重复性测试,变异系数为4.6%,重复性较好。该分析仪满足临床检测需求,在痕量疾病标志物检测领域具有广阔的应用前景。

Development of a portable trace cTnI detecting instrument based on enzymatic chemiluminescence

Cardiac troponin I(cTnI) is a gold standard marker for the diagnosis of myocardial infarction.In this paper,a portable trace cTnI detecting instrument based on enzymatic chemiluminescence is described.Different from existing detecting system,our instrument is prepared using a new-type alkaline phosphatase substrate AMPPD,which shows low background and strong signal after separation and enrichment with magnetic beads.The optical and photoelectric conversion module is sealed in an aluminum black box,which can effectively avoid the interference of stray light from the outside world.The instrument is easy to integrate and sensitive for trace level detection with a confocal light path,and a photomultiplier tube is used as the sensing element.In addition,the automatic injection unit greatly reduces the human operation error.Experiment results for detection of cTnI solution with concentration of 0.03 ~ 30 ng/mL shows a good linear relationship,and the correlation coefficient R=0.99.The variation coefficient is 4.6% in the repeatability test.The instrument meets the requirements of clinical testing and has great potential application prospect in trace disease marker measurement.