银染增强的纳米金标记探针对微量核酸的检测

本研究利用银染增强的纳米金技术建立了一种简单快速的核酸定量方法.该方法基于纳米金与烷巯基修饰的寡核苷酸分子共价键合作用，将纳米微粒报告基团标记在与靶核酸一端序列互补的寡核苷酸上，同时生物素化修饰另一端互补序列.靶核酸与两段寡核苷酸探针杂交后，借亲和素固定在酶标板孔内，通过纳米金催化的银染放大效应产生高灵敏的识别信号,适时记录其吸光度值从而实现核酸分子的定量.该检测方法检测单链核酸分子的灵敏度达0.1 fM，双链分子为10 fM.

A Colorimetric Polynucleotides Detection Method Based on Nanoparticle Probes with Silver Staining Enhancement

A simple gold nanoparticle-based method to detect micro amount of polynucleotide molecules with silver staining enhancement is established.Based on the covalence action of thiol-modified oligonucleotides with nanoparticles,the nanoparticles was utilized as biomarkers to detect trace amount of polynucleotides.Two kinds of probes,which were respectively complementary to one half of target polynucleotides,were labeled respectively with biotins and nanoparticles.The hybridization products of target polynucleotides with these two kinds of probes were immobilized to microplates via avidin-biotin system,and the signals of gold nanoparticles were subsequently amplified by silver staining solution,and recorded with colorimetric absorbance.This sandwich colorimetric assay can detect as few as 0.1 fmol/L for single-strand target polynucleotides and 10 fmol/L for double-strand target polynucleotides.