基于纳米金复合探针-蛋白芯片检测心肌损伤标志物

Detection of Myocardial Injury Markers Based on Double Gold Nanoparticles Probes and Protein Chip

运用纳米金复合探针结合蛋白芯片,建立了一种检测心肌损伤标志物的新方法.构建了2种纳米金探针:标记有检测抗体和DNA探针1的检测探针和标记有DNA探针2(与DNA探针1的碱基互补配对)的信号探针.当目的抗原存在时,检测探针经检测抗体和抗原,与芯片上捕获抗体结合固定在芯片上,信号探针通过碱基互补配对与检测探针结合使信号放大,最后利用纳米金成核原理染色,通过显微镜观察结果并定量分析.该体系在40 min内可检测多种标志物,其中肌钙蛋白Ⅰ(c TnⅠ)的检出限为10 pg/m L,与临床电化学发光法(ECLIA)灵敏度相当;肌红蛋白(MYO)与新型脂肪酸结合蛋白(HFABP)的检出限分别为640和10 pg/m L,与ECLIA及酶联免疫吸附法(ELISA)相比,灵敏度显著提高.

A novel method based on gold nanoparticles（ Au NPs） probes and protein chip was developed to detect myocardial injury markers. Two Au NPs probes were constructed： one was modified with detection antibody and DNA probe 1（ detection probe）,and the other was labeled with DNA probe 2 which was complementary to DNA probe 1（ signal probe）. When target antigen was present,a sandwich structure（ capture antibody-target antigen-detection probe-signal probe） was formed through the interaction of the antibody-antigen and the hybridization of complemenatry DNAs. Then the chip was dyed by the gold deposition solution,and the signal was amplified. The results were observed with a microscope linked with an image analysis software. This system could simultaneously detect multiple markers in 40 min. The detection limit of c Tn Ⅰ was 10 pg / m L,which was equivalent to ECLIA in clinical. For HFABP and MYO,the detection limit could be as low as 640 and 10 pg / m L,respectively,and the sensitivity was improved greatly when compared with ECLIA and ELISA.