Hall W Paige, Ngatia Salome N, Van Duyne Richard P
Department of Chemistry, Northwestern University, 2145 North Sheridan Road, Evanston, Illinois 60208, United States.
J Phys Chem C Nanomater Interfaces. 2011 Feb 10;115(5):1410-1414. doi: 10.1021/jp106912p.
A method to amplify the wavelength shift observed from localized surface plasmon resonance (LSPR) bioassays is developed using gold nanoparticle-labeled antibodies. The technique, which involves detecting surface-bound analytes using gold nanoparticle conjugated antibodies, provides a way to enhance LSPR shifts for more sensitive detection of low-concentration analytes. Using the biotin and antibiotin binding pair as a model, we demonstrate up to a 400% amplification of the shift upon antibody binding to analyte. In addition, the antibody-nanoparticle conjugate improves the observed binding constant by 2 orders of magnitude, and the limit of detection by nearly 3 orders of magnitude. This amplification strategy provides a way to improve the sensitivity of plasmon-based bioassays, paving the way for single molecule-based detection and clinically relevant diagnostics.
一种利用金纳米颗粒标记抗体来放大局部表面等离子体共振（LSPR）生物测定中观察到的波长偏移的方法被开发出来。该技术涉及使用金纳米颗粒偶联抗体来检测表面结合的分析物，为增强LSPR偏移以更灵敏地检测低浓度分析物提供了一种方法。以生物素和抗生物素蛋白结合对为模型，我们证明了抗体与分析物结合时偏移放大高达400%。此外，抗体-纳米颗粒偶联物将观察到的结合常数提高了2个数量级，检测限提高了近3个数量级。这种放大策略为提高基于等离子体的生物测定的灵敏度提供了一种方法，为基于单分子的检测和临床相关诊断铺平了道路。
