Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Biosens Bioelectron. 2011 Jan 15;26(5):2165-70. doi: 10.1016/j.bios.2010.09.026. Epub 2010 Sep 22.
There has been immense interest in both instruments and methods to enhance fluorescence signal and achieve highly sensitive fluoroimmunoassay (FIA). In this paper, we present a facile, low-cost and general method of biotinylated colloidal photonic crystal (PC) to improve the FIA of avidin (avidin FIA). The fluorescence signal intensity of the avidin FIA on the colloidal PC can be enhanced over two orders of magnitude relative to the control sample, attributed to the large surface area, resonance field and coherent scattering effect of the colloidal PC. The detection limit is shrunk to 1/69 of that of the control sample. Furthermore, the signal to interference ratio (S/I ratio) is increased because the band-edge induced fluorescence enhancement is wavelength-selective. The interference fluorescence does not go up proportionally while the signal is significantly enhanced by the colloidal PCs. It is believed that the colloidal PC modified with biotin can act as an effective material for a general and sensitive fluoroimmunoassay.
人们对增强荧光信号和实现高灵敏度荧光免疫分析（FIA）的仪器和方法产生了浓厚的兴趣。在本文中，我们提出了一种简便、低成本且通用的方法，即用生物素化胶体光子晶体（PC）来提高亲和素（avidin FIA）的荧光免疫分析性能。与对照样品相比，胶体 PC 上的avidin FIA 的荧光信号强度可以增强两个数量级，这归因于胶体 PC 的大表面积、共振场和相干散射效应。检测限缩小到对照样品的 1/69。此外，由于边缘诱导的荧光增强具有波长选择性，因此信号与干扰比（S/I 比）增加。当胶体 PC 显著增强信号时，干扰荧光不会成比例增加。可以相信，用生物素修饰的胶体 PC 可以作为一种通用且灵敏的荧光免疫分析的有效材料。
