State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, PR China.
Biosens Bioelectron. 2014 Mar 15;53:346-54. doi: 10.1016/j.bios.2013.10.007. Epub 2013 Oct 14.
A surfactant-free and template-free method for the high-yield synthesis of biomolecule (serotonin)-based formaldehyde resin (BFR) microspheres is proposed for the first time. The colloidal microspheres loaded with Au nanoparticles (AuNPs) prepared by a convenient in-situ synthesis of AuNPs on BFR (AuNPs/BFR) microsphere surface show good stability. AuNPs/BFR microspheres not only favor the immobilization of antibody but also facilitate the electron transfer. It is found that the resultant AuNPs/BFR microspheres can be designed to act as a sensitive label-free electrochemical immunosensor for carcinoembryonic antigen (CEA) determination. The immunosensor is prepared by immobilizing capture anti-CEA on AuNPs/BFR microspheres assembled on thionine (TH) modified glassy carbon electrode (GCE). TH acts as the redox probe. Under the optimized conditions, the linear range of the proposed immunosensor is estimated to be from 25 pg/mL to 2000 pg/mL (R=0.998) and the detection limit is estimated to be 3.5 pg/mL at a signal-to-noise ratio of 3. The prepared immunosensor for detection of CEA shows high sensitivity, reproducibility and stability. Our study demonstrates that the immunosensor can be used for the CEA detection in humans serum.
首次提出了一种无表面活性剂和模板的方法，用于高产率合成基于生物分子（血清素）的甲醛树脂（BFR）微球。通过在 BFR（AuNPs/BFR）微球表面上方便地原位合成 AuNPs 制备的负载 Au 纳米粒子（AuNPs）的胶体微球显示出良好的稳定性。AuNPs/BFR 微球不仅有利于抗体的固定，而且有利于电子转移。结果表明，所得的 AuNPs/BFR 微球可用作灵敏的无标记电化学免疫传感器，用于测定癌胚抗原（CEA）。该免疫传感器是通过将捕获抗-CEA 固定在组装在硫堇（TH）修饰的玻碳电极（GCE）上的 AuNPs/BFR 微球上制备的。TH 用作氧化还原探针。在优化条件下，所提出的免疫传感器的线性范围估计为 25 pg/mL 至 2000 pg/mL（R=0.998），检测限估计为 3.5 pg/mL，信噪比为 3。用于检测 CEA 的制备免疫传感器具有高灵敏度、重现性和稳定性。我们的研究表明，该免疫传感器可用于检测人血清中的 CEA。
