Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, People's Republic of China.
Biosens Bioelectron. 2012 Aug-Sep;37(1):6-10. doi: 10.1016/j.bios.2012.04.010. Epub 2012 May 1.
A novel electrochemiluminescence (ECL) immunosensor for ultrasensitive detection of α-1-fetoprotein (AFP) was designed based on the in situ bi-enzymatic reaction to generate coreactant of peroxydisulfate for signal amplification. In this work, AuNPs were electrodeposited on the glassy carbon electrode (GCE) surface, which promoted the electron transfer. Then, L-cysteine and another layer of AuNPs were, respectively assembled onto the modified electrode surface, which formed the multilayer films for amplifying the ECL signal of peroxydisulfate and immobilizing antibody. At last, glucose oxidase (GOD) and horseradish peroxidase (HRP) were employed to block the nonspecific binding sites. When proper amounts of glucose were added in the detection solution, GOD catalyzed the oxidation of glucose to generate H(2)O(2), which could be further catalyzed by HRP to generate O(2) for the signal amplification. The linear range for AFP detection was 0.001-100 ng mL(-1), with a low detection limit of 3.3 × 10(-4) ng mL(-1). The novel strategy has the advantages of simplicity, sensitivity, good selectivity and reproducibility which might hold a new promise for highly sensitive bioassays applied in clinical detection.
基于原位双酶反应生成过二硫酸盐的共反应物用于信号放大，设计了一种用于超灵敏检测甲胎蛋白（AFP）的新型电化学发光（ECL）免疫传感器。在这项工作中，AuNPs 被电沉积在玻碳电极（GCE）表面，这促进了电子转移。然后，L-半胱氨酸和另一层 AuNPs 分别被组装到修饰电极表面上，形成用于放大过二硫酸盐的 ECL 信号和固定抗体的多层膜。最后，葡萄糖氧化酶（GOD）和辣根过氧化物酶（HRP）被用来阻止非特异性结合位点。当在检测溶液中加入适量的葡萄糖时，GOD 催化葡萄糖氧化生成 H(2)O(2)，H(2)O(2)可进一步被 HRP 催化生成 O(2)以用于信号放大。AFP 检测的线性范围为 0.001-100 ng mL(-1)，检测限低至 3.3 × 10(-4) ng mL(-1)。这种新策略具有简单、灵敏、良好的选择性和重现性的优点，有望为应用于临床检测的高灵敏度生物测定提供新的前景。
