Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
Biosens Bioelectron. 2015 Jan 15;63:465-471. doi: 10.1016/j.bios.2014.07.081. Epub 2014 Aug 7.
A novel non-enzymatic immunoassay was designed for ultrasensitive electrochemical detection of carcino-embryonic antigen (CEA) using β-cyclodextrin functionalized Cu@Ag (Cu@Ag-CD) core-shell nanoparticles as labels and β-cyclodextrin functionalized graphene nanosheet (CD-GN) as sensor platform. CD-GN has excellent conductivity which promoted the electric transmission between base solution and electrode surface and enhanced sensitivity of immunosensor. In addition, owing to supramolecular recognition of CD-GN for the guest molecule, quite a few synthesized adamantine-modified primary antibodies (ADA-Ab1) were immobilized on the CD-GN by supramolecular host-guest interaction between CD and ADA. Cu@Ag-CD as a signal tag could be captured by ADA-modified secondary antibody (ADA-Ab2) through a host-guest interaction, leading to a large loading of Cu@Ag nanoparticles with high electrical conductivity and catalytic activity. The fabricated immunosensor exhibits excellent analytical performance for the measurement of CEA with wide range linear (0.0001-20 ng/mL), low detection limit (20 fg/mL), good sensitivity, reproducibility and stability, which provide an enormous application prospect in clinical diagnostics.
设计了一种新颖的非酶免疫分析方法，用于超灵敏电化学检测癌胚抗原（CEA），使用β-环糊精功能化的 Cu@Ag（Cu@Ag-CD）核壳纳米粒子作为标记物，β-环糊精功能化的石墨烯纳米片（CD-GN）作为传感器平台。CD-GN 具有优异的导电性，促进了基底溶液和电极表面之间的电子传递，提高了免疫传感器的灵敏度。此外，由于 CD-GN 对客体分子的超分子识别，相当数量的合成的金刚烷修饰的一抗（ADA-Ab1）通过 CD 和 ADA 之间的超分子主客体相互作用固定在 CD-GN 上。Cu@Ag-CD 作为信号标记物可以通过主客体相互作用被 ADA 修饰的二抗（ADA-Ab2）捕获，导致具有高导电性和催化活性的 Cu@Ag 纳米粒子的大量负载。所构建的免疫传感器在测量 CEA 方面表现出优异的分析性能，具有较宽的线性范围（0.0001-20ng/mL）、较低的检测限（20fg/mL）、良好的灵敏度、重现性和稳定性，为临床诊断提供了广阔的应用前景。
