Nie Guangming, Li Chenxi, Zhang Lin, Wang Ling
State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, People's Republic of China.
J Mater Chem B. 2014 Dec 21;2(47):8321-8328. doi: 10.1039/c4tb01308e. Epub 2014 Oct 2.
A simple and sensitive label-free QDs-based electrochemiluminescence (ECL) immunosensor for detecting tumor markers alpha-fetoprotein is reported. This probe is fabricated using a nanostructured composite material (PICA-MWNT) obtained by the direct electrodeposition of indole-6-carboxylic acid (ICA) monomers and carboxylic groups terminated multiwalled carbon nanotubes (MWNTs) in one step. The obtained composite material, with 2-aminoethanethiol modified CdSe nanoclusters as luminescent particles, has a larger surface area and a considerable amount of functionalized carboxylic acid groups. Thus, QDs/PICA-MWNT will probably display good biocompatibility, high ECL intensity, and stability, which is promising for the enhancement of detection signals and synergistic improvement of sensitivity. The ECL signals are logarithmically linear with the concentration of alpha-fetoprotein in a wide determination range from 0.002 to 2000 ng mL, and the corresponding detection limit was 0.4 pg mL. This proposed ECL sensor exhibits high stability, good selectivity, and reproducibility, which offers a new insight into the fabrication of immunoassays for detecting other relevant biomarkers, and it has the potential for a reliable point-of-care diagnostics of tumor or other diseases.
报道了一种用于检测肿瘤标志物甲胎蛋白的简单、灵敏的无标记量子点基电化学发光（ECL）免疫传感器。该探针采用一种纳米结构复合材料（PICA-MWNT）制备，该复合材料通过一步直接电沉积吲哚-6-羧酸（ICA）单体和羧基封端的多壁碳纳米管（MWNTs）获得。所获得的复合材料以2-氨基乙硫醇修饰的CdSe纳米团簇作为发光颗粒，具有更大的表面积和大量功能化羧酸基团。因此，量子点/PICA-MWNT可能表现出良好的生物相容性、高ECL强度和稳定性，这对于增强检测信号和协同提高灵敏度很有前景。在0.002至2000 ng/mL的宽测定范围内，ECL信号与甲胎蛋白浓度呈对数线性关系，相应的检测限为0.4 pg/mL。所提出的ECL传感器具有高稳定性、良好的选择性和重现性，为检测其他相关生物标志物的免疫分析的制备提供了新的思路，并且具有用于肿瘤或其他疾病可靠的即时诊断的潜力。
