Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, Jilin University, Xi-an Road 5333, Changchun, Jilin 130062, PR China.
Biosens Bioelectron. 2011 Apr 15;26(8):3700-4. doi: 10.1016/j.bios.2011.02.008. Epub 2011 Feb 16.
A novel probe based on colloidal gold nanoparticles (AuNPs) modified with goat anti-mouse IgG and horseradish peroxidase (HRP) was synthesized and an enhanced enzyme-linked immunosorbent assay (ELISA) based on the probe was developed. In the assay, the synthesized probe is bound with a monoclonal antibody (McAb) which is competitively bound by coated BSA-ITCBE-Pb(II) on plate and Pb(II) in samples. The HRP, used here for signal amplification catalytically oxidize the substrate and generate optical signals that is related to the concentration of Pb(II) and can be measured spectrophotometrically. For the monodisperse AuNPs having high surface areas, it can be conjugated with more amount of HRP than that of IgG. Therefore, compared with traditional ELISA, the signal amplification of catalytically oxidized substrate was enhanced. The detection limit for this novel modified AuNPs probe-based assay was 9 pg mL(-1). The recoveries obtained by standard Pb(II) addition to real samples, including a commercial mineral water, tap water, and lake water were all from 94.9% to 102.9%. And the coefficient of variation (CV) value of all samples was less than 10%. The results indicated that the enhanced assay gave higher sensitivity and reliable reproducibility. It could provide a general detection format for low-molecular weight contaminants.
基于胶体金纳米粒子（AuNPs）修饰的山羊抗小鼠 IgG 和辣根过氧化物酶（HRP）的新型探针被合成，并且基于该探针开发了增强型酶联免疫吸附测定（ELISA）。在该测定中，合成的探针与单克隆抗体（McAb）结合，该抗体与板上涂覆的 BSA-ITCBE-Pb（II）和样品中的 Pb（II）竞争结合。此处使用的 HRP 可催化氧化底物并产生与 Pb（II）浓度相关的光学信号，并且可以分光光度法测量。对于具有高表面积的单分散 AuNPs，可以比 IgG 结合更多量的 HRP。因此，与传统 ELISA 相比，催化氧化底物的信号放大得到了增强。该新型修饰的 AuNPs 探针测定的检测限为 9 pg mL（-1）。通过向实际样品（包括商业矿泉水、自来水和湖水）中添加标准 Pb（II）获得的回收率均在 94.9%至 102.9%之间。并且所有样品的变异系数（CV）值均小于 10%。结果表明，增强的测定法具有更高的灵敏度和可靠的重现性。它可以为低分子量污染物提供通用的检测格式。
