Key Laboratory of Analysis and Detection for Food Safety (Ministry of Education & Fujian Province), Department of Chemistry, Fuzhou University, Fuzhou, China.
Biosens Bioelectron. 2011 Sep 15;27(1):153-9. doi: 10.1016/j.bios.2011.06.034. Epub 2011 Jul 2.
A new magneto-controlled microfluidic device for direct electrochemical determination of squamous cell carcinoma antigen (SCC-Ag) in serum was designed by using anti-SCC antibody (SCC-Ab)-functionalized magnetic mesoporous nanogold/thionine/NiCo(2)O(4) hybrid nanostructures as immunosensing probes (P(1)-Ab) and horseradish peroxidase-SCC-Ab conjugates-labeled nanogold/graphene nanosheets as signal tags (P(2)-Ab). In the presence of the analyte SCC-Ag, the sandwich immunocomplex was formed between the immunosensing probes and the signal tags. With the aid of an external magnet, the formed immunocomplex was attached to the microfluidic device. The assay was implemented in newborn calf serum (NBCS) containing 2.5 mM H(2)O(2) based on the labeled peroxidase on the P(2)-Ab toward the catalytic reduction of H(2)O(2). Under optimal conditions, the increase in the current was proportional to the concentration of SCC-Ag from 2.5 pg/mL to 15 ng/mL. The detection limit (LOD) was 1.0 pg/mL SCC-Ag at 3s(B). The electrochemical immunoassay displayed an acceptable precision, selectivity and stability. Clinical serum specimens were assayed with the method, and the results were in acceptable agreement with those obtained from the referenced electrochemiluminescent method. Importantly, the method can be suitable for on-line use in the mass production of miniaturized lab-on-a-chip devices and open a new opportunity for protein diagnostics and biosecurity.
一种新的磁控微流控装置，用于直接电化学测定血清中的鳞状细胞癌抗原（SCC-Ag），该装置使用抗 SCC 抗体（SCC-Ab）功能化的磁性介孔纳米金/硫堇/NiCo(2)O(4)杂化纳米结构作为免疫传感探针（P(1)-Ab）和辣根过氧化物酶-SCC-Ab 标记的纳米金/石墨烯纳米片作为信号标签（P(2)-Ab）。在分析物 SCC-Ag 的存在下，免疫传感探针和信号标签之间形成夹心免疫复合物。在外加磁场的帮助下，形成的免疫复合物被附着到微流控装置上。该测定法在含有 2.5mM H(2)O(2)的新生牛血清（NBCS）中进行，基于 P(2)-Ab 上的标记过氧化物酶对 H(2)O(2)的催化还原。在最佳条件下，电流的增加与 SCC-Ag 的浓度从 2.5pg/mL 到 15ng/mL 成正比。SCC-Ag 的检测限（LOD）为 1.0pg/mL，在 3s(B)时。电化学免疫分析显示出可接受的精度、选择性和稳定性。用该方法测定临床血清标本，结果与参考电化学发光法所得结果相符。重要的是，该方法可适用于在线使用，大规模生产微型化的芯片实验室设备，并为蛋白质诊断和生物安全开辟新的机会。
