基于蚀刻硅纳米线阵列辅助的表面增强拉曼散射的银纳米立方体介导的灵敏免疫分析。

Silver nanocube-mediated sensitive immunoassay based on surface-enhanced Raman scattering assisted by etched silicon nanowire arrays.

作者信息

Jiang Tao, Zhang Li, Zhou Jun

机构信息

Department of Microelectronic Science and Engineering, Faculty of Science, Ningbo University, Ningbo 315211, P. R. China.

出版信息

Analyst. 2014 Nov 21;139(22):5893-900. doi: 10.1039/c4an01293c.

DOI:10.1039/c4an01293c

PMID:25243249

Abstract

An immunoassay based on surface enhanced Raman scattering (SERS) has been developed using immuno-silver nanocubes (NCs) and silicon nanowires with high sensitivity. The features of the samples were characterized by XRD profiles, absorption spectra, SEM, TEM, and AFM images, EDS analyses, and SERS spectra. It was found that the obtained silver NCs maintained higher SERS activity than silver nanospheres. After the silver NCs were modified by an antibody and employed in immunoassay with silicon nanowire arrays as the substrate, the antigen concentration-dependent SERS spectra and dose-response calibration curves were obtained. The detection limit of a prostate-specific antigen in this immunosystem was as low as 2 × 10(-14) g ml(-1), attributing to the significant electromagnetic coupling effect generated between the densely packed silver NCs and the SERS-active silicon nanowire arrays. It can be inferred that this proposed strategy will show great advantages in sensitive immunoassay and other biochemical examinations.

摘要

基于表面增强拉曼散射（SERS）的免疫分析方法已通过使用具有高灵敏度的免疫银纳米立方体（NCs）和硅纳米线得以开发。通过X射线衍射图谱、吸收光谱、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、原子力显微镜（AFM）图像、能谱分析（EDS）以及SERS光谱对样品的特征进行了表征。结果发现，所制备的银纳米立方体比银纳米球保持更高的SERS活性。在用抗体修饰银纳米立方体并将其用于以硅纳米线阵列作为底物的免疫分析后，获得了抗原浓度依赖性的SERS光谱和剂量响应校准曲线。该免疫分析系统中前列腺特异性抗原的检测限低至2×10（-14）g/ml（-1），这归因于紧密堆积的银纳米立方体与具有SERS活性的硅纳米线阵列之间产生的显著电磁耦合效应。可以推断，该所提出的策略在灵敏免疫分析和其他生化检测中将显示出巨大优势。