基于表面增强拉曼散射的纳米生物传感器用于p53基因的超灵敏检测  

SERS-based nanobiosensing for ultrasensitive detection of the p53 tumor suppressor

作　　者：叶祖峰[1] 陈伟[1] 潘一峰[1] 

机构地区：[1]中南大学肝胆肠外科研究中心,湖南长沙410008

出　　处：《中国现代医学杂志》2014年第30期1-7,共7页China Journal of Modern Medicine

摘　　要：目的制备超灵敏检测p53基因的基于表面增强拉曼散射的纳米生物传感器。方法 p53分子通过双官能团连接4-氨基苯硫酚（4-ATP）的方式固定在金纳米粒子上。p53-4-ATP纳米粒子系统的特征振动谱带用来识别p53分子,当这些分子被包含有单分子层天青蛋白分子中有对这种抑癌基因显著亲和力的识别衬底捕获。结果由4-ATP介导交联p53-50 nm金纳米颗粒实现的拉曼信号增强使在浓度低至5×10^-13M时检测出这种蛋白。p53-4-ATP纳米粒子系统可显著提高拉曼指纹图谱信号,振动功能容易分辨,时间较为稳定,且在低浓度下很容易检测出目的蛋白及分析时间相对较短。铜蓝蛋白包被的基板与p53-4-ATP纳米粒子溶液孵育后,采用TM-AFM检测可观察到大的斑点,这表明纳米粒子在基板上有效沉积,及共存的铜蓝蛋白与p53之间特异性复合物的形成。结论基于铜蓝蛋白的SERS方法检测p53肿瘤抑制基因的方法具有高灵敏度和选择性。能够检测到p53的最低浓度是5×10^-13M,在血清甚至血清环境中其他生物分子存在的情况下能够选择性地检测到p53。【Objective】A new ultrasensitive detection of the p53 tumor suppressor SERS-based nanobiosensing were prepared. 【Methods】p53 molecules were anchored to gold nanoparticles by means of the bi-functional linker4-aminothiophenol（4-ATP）. The characteristic vibrational bands of the p53-4-ATP nanoparticle system were then used to identify the p53 molecules when they were captured by a recognition substrate comprising a monolayer of azurin in molecules possessing significant affinity for this tumor suppressor. 【Results】The Raman signal enhancement achieved by 4-ATP-mediated crosslinking of p53 to 50 nm gold nanoparticles enabled detect of this protein at a concentration down to 5×10-13 M. Our Raman-SERS results show that the p53-4-ATP nanoparticle system exhibits remarkable enhancement of the fingerprint Raman signal, From the signal to noise intensity ratio of the C-S stretching mode（around 1 089 cm-1and 1 078 cm-1for the solid 4-ATP and the 4-ATP nanoparticle system, respectively）,enhancement due to a SERS effect of about seven orders of magnitude was estimated. Our SERS-based detection approach is amenable to further improvements of the enhancement factor by optimizing the dimensions of the gold nanoparticles, the distance between the Raman marker and the nanoparticle surface, and perhaps even the arrangement of azurin molecules on the substrate. 【Conclusions】The proposed azurin-based SERS approach for detection of the p53 tumor suppressor combines high sensitivity and selectivity. It is able to detect p53 at a concentration of5×10-13 M, with the further ability to reveal the target biomolecule selectively in the presence of human serum albu-min, and even in the serum environment in which other biomolecules are present.

关 键 词：表面增强拉曼光谱 P53 超灵敏检测 原子力显微镜 

分 类 号：Q657.37[生物学—生物物理学]