School of Chemistry and Chemical Engineering, Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Jiangning District, Nanjing, 211189, P.R. China.
Analyst. 2013 Mar 7;138(5):1483-9. doi: 10.1039/c2an36513h.
A rapid sandwiched immunoassay of microcystin-LR (MC-LR) in water is proposed with flow injection chemiluminescence detection. The magnetic beads (MBs) were first modified with polyethyleneimine (PEI) by acylamide bond between the carboxyl group on the surface of MBs and the primary amine group in PEI, followed by immobilizing of anti-MC-LR (Ab1) onto PEI with glutaraldehyde as linkage. The resulting Ab1 modified MBs captured the target MC-LR in water, reacted with the horseradish peroxidase and anti-MC-LR co-immobilized silica nanoparticles, and were detected with flow injection chemiluminescence. When using PEI/MBs as the carrier of anti-MC-LR, the CL signal was greatly enhanced up to 9-fold compared to that using MBs without PEI modification. The CL signal was further amplified 13-fold when Si/Ab2 was used as the signal probe. Under the optimal conditions, the present immunoassay exhibited a wide quantitative range from 0.02 to 200 μg L(-1) with a detection limit of 0.006 μg L(-1), which was much lower than the WHO provisional guideline limit of 1.0 μg L(-1) for MC-LR in drinking water. The relative standard deviation was 4.8% and the recoveries for the spiked samples ranged from 84% to 115%, which indicated acceptable precision and accuracy for MC-LR. The present method is easier to perform and less time-consuming (the entire analysis process lasted about 40 minutes) and has been applied to the detection of MC-LR in different water samples successfully.
建立了一种基于流动注射化学发光法检测水中微囊藻毒素-LR（MC-LR）的快速夹心免疫分析方法。首先通过 MBs 表面的羧基与 PEI 中的伯胺基团之间的酰亚胺键将 MBs 用聚乙烯亚胺（PEI）修饰，然后用戊二醛将抗 MC-LR（Ab1）固定在 PEI 上。所得 Ab1 修饰的 MBs 捕获水中的目标 MC-LR，与固定在辣根过氧化物酶和抗 MC-LR 上的硅纳米粒子反应，并用流动注射化学发光法进行检测。当使用 PEI/MBs 作为抗 MC-LR 的载体时，与未用 PEI 修饰的 MBs 相比，CL 信号大大增强了 9 倍。当使用 Si/Ab2 作为信号探针时，CL 信号进一步放大了 13 倍。在最佳条件下，本免疫分析方法的定量范围从 0.02 到 200 μg L(-1)，检测限为 0.006 μg L(-1)，远低于世界卫生组织暂定饮用水中 MC-LR 的 1.0 μg L(-1)指导限值。相对标准偏差为 4.8%，加标样品的回收率在 84%到 115%之间，表明该方法对 MC-LR 具有良好的精密度和准确度。与传统的酶联免疫吸附测定法相比，该方法具有操作简单、耗时少（整个分析过程约 40 分钟）等优点，已成功应用于不同水样中 MC-LR 的检测。
