Key Laboratory of Eco-chemical Engineering, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, China.
Anal Biochem. 2011 Jul 1;414(1):84-7. doi: 10.1016/j.ab.2011.03.007. Epub 2011 Mar 10.
An electrochemical cytosensor was designed based on the specific recognition of mannosyl on a cell surface to concanavalin A (ConA) and the signal amplification of gold nanoparticles (NPs). By sandwiching a cancer cell between a gold electrode modified with ConA and the gold NPs with ConA and 6-ferrocenylhexanethiol (Fc), the electrochemical cytosensor was established. The cell number and the amount of cell surface mannose moieties were quantified by cyclic voltammetry (CV) analysis of the Fc loaded on the surface of the gold NPs. Since a single gold NP could be loaded with hundreds of Fc, a significant amplification for the detection of target cell was obtained. By using K562 leukemic cells (K562 cells) as a model, the electrochemical response was proportional to the cell concentration in the range from 1.0×10(2) to 1.0×10(7) cells mL(-1), showing very high sensitivity. The signal amplification could be further used to evaluate the cell surface mannose moieties, and the amount of mannose moieties on a single living K562 cell was detected to correspond to 4.7×10(9) molecules of free mannose. This strategy presents a promising platform in a highly sensitive cytosensor and convenient estimation of cell surface carbohydrate.
基于细胞表面甘露糖与伴刀豆球蛋白 A（ConA）的特异性识别，以及金纳米粒子（NPs）的信号放大作用，设计了一种电化学细胞传感器。通过将癌细胞夹在修饰有 ConA 的金电极和带有 ConA 和 6-巯基己基-1- 二茂铁（Fc）的金 NPs 之间，建立了电化学细胞传感器。通过对金 NPs 表面上加载的 Fc 进行循环伏安（CV）分析，定量了细胞数量和细胞表面甘露糖部分的数量。由于单个金 NPs 可以负载数百个 Fc，因此可以获得对靶细胞检测的显著放大。使用 K562 白血病细胞（K562 细胞）作为模型，电化学响应与细胞浓度在 1.0×10(2)至 1.0×10(7)细胞 mL(-1)范围内成正比，表现出非常高的灵敏度。信号放大还可用于评估细胞表面甘露糖部分，并且检测到单个活 K562 细胞表面的甘露糖部分对应于 4.7×10(9)个游离甘露糖分子。该策略在高灵敏度细胞传感器和方便的细胞表面碳水化合物评估方面提供了一个很有前途的平台。
