化学学报 ›› 2009, Vol. 67 ›› Issue (14): 1603-1608. 上一篇    下一篇

研究论文

SERS标记的金纳米棒探针用于免疫检测

郭红燕 芦玲慧 吴 超 潘建高 胡家文

  

  1. (湖南大学化学生物传感与计量学国家重点实验室 生物医学工程中心 化学化工学院 长沙 410082)

  • 投稿日期:2009-03-02 修回日期:2009-04-05 发布日期:2009-07-28
  • 通讯作者: 胡家文

SERS Tagged Gold Nanorod Probes for Immunoassay Application

Guo, Hongyan Lu, Linghui Wu, Chao Pan, Jiangao Hu, Jiawen*   

  1. (State Key Laboratory for Chemo/Biosensing and Chemometrics, Biomedical Engineering Center, and College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082)
  • Received:2009-03-02 Revised:2009-04-05 Published:2009-07-28
  • Contact: Hu, Jiawen

报道了基于金纳米棒表面增强拉曼散射(SERS)的免疫检测. 将拉曼活性分子对巯基苯甲酸吸附于金纳米棒表面, 制备出SERS标记的金纳米棒探针. 该探针和蛋白抗体结合形成SERS标记抗体. 通过SERS标记抗体、待测抗原和俘获抗体(固体基底上修饰的抗体, 即俘获抗体)之间的免疫应答反应, 将金纳米棒探针组装到固体基底上, 形成SERS标记抗体-抗原-俘获抗体 “三明治”夹心复合体. 待测抗原浓度越大, 固体基底上俘获的金纳米棒探针的数目越多, 从而可通过SERS信号的强弱来检测待测抗原的浓度. 由于金纳米棒的表面等离子体共振(SPR)峰位置可以在较宽的范围内调控, 可通过激发光和SPR的耦合来提高SERS信号, 从而提高免疫检测的灵敏度. 单组分抗原可检出的浓度范围高于1×10-8 mg/mL.

关键词: 金钠米棒, 巯基聚乙二醇, 对巯基苯甲酸, 免疫分析, 表面增强拉曼散射

An immunoassay detection based on surface-enhanced Raman scattering (SERS) from gold nanorods (NRs) was studied. Raman active molecule 4-mercaptobenzoic acid was adsorbed on gold NRs, forming SERS-tagged gold nanoprobes. Upon adsorption of antibody to the nanoprobes, the antibody was tagged by SERS. Through the immunoassay reactions among the SERS-tagged antibody, detected antigen, and antibody supported on solid substrate (capture antibody), SERS-tagged antibody-antigen-capture antibody sandwich conjugates were formed on the solid substrate. The higher the concentration of the detected antigen is, the larger the number of the gold nanoprobes on the solid substrate is. Therefore, SERS intensity signals the concentration of the detected antigen. Because the position of surface plasmon resonance (SPR) of the gold NRs can be tuned in a wide range, one can couple the SPR and the excitation line to maximize the SERS signals and thus the immunoassay sensitivity. The detected concentration for a single antigen component is higher than 1×10-8 mg•mL-1.

Key words: gold nanorod, thiolated PEG, 4-mercaptobenzoic acid, immunoassay, surface-enhanced Raman scattering