碳纳米管负载银修饰电极杂交链式反应检测DNA

牛淑妍， 崔欢欢， 娄晓飞

（青岛科技大学 化学与分子工程学院，山东 青岛 266042）

摘要： 将银纳米粒子固定在碳纳米管修饰的玻碳电极表面，同时利用杂交链式反应进行放大，以邻菲罗啉钴为指示剂，制备了一种新的灵敏度高的DNA电化学生物传感器。通过循环伏安法（CV）和交流阻抗法（EIS）对修饰电极进行表征。由于碳纳米管和银纳米粒子的修饰，大大增强了玻碳电极的有效表面积及导电性能，提高了该电化学生物传感器的灵敏度。对目标DNA的检测线性范围为10×10-10～14×10-9 mol·L-1，检测限为135×10-11 mol·L-1（S/N=3）。

关键词： 电化学传感器； DNA检测； 碳纳米管； 银纳米粒子； 杂交链式反应

中图分类号： O 657.32             文献标志码： A

Detection of DNA Based on Carbon Nanotubes/Silver Nanoparticles Modified Electrode and Hybridization Chain Reaction

NIU Shuyan, CUI Huanhuan, LOU Xiaofei

(College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China)

Abstract: A novel and sensitive electrochemical DNA biosensor was developed for the detection of DNA hybridization. The biosensor was developed by using ［Co(phen)2Cl·H2O］+ as an electroactive indicator based on multiwalled carbon nanotubes/silver nanoparticles (Ag/MWCNTs) modified glassy carbon electrode and enhanced by hybridization chain reaction. The modified electrodes were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). As a result of carbon nanotubes and silver nanoparticles, the effective surface area and conductivity of glassy carbon electrode was greatly enhanced, and the sensitivity of the electrochemical biosensor was improved. It was shown that the sensor has a good selectively detection for target DNA with a linear range from 10×10-10 mol·L-1 to 14×10-9 mol·L-1, with a detection limit of 135×10-11 mol·L-1(S/N=3).

key words: electrochemical sensor；DNA detection； carbon nanotubes；silver nanoparticles； hybridization chain reaction

收稿日期：20131114

基金项目：国家自然科学基金项目(21075073)； 山东省自然科学基金重点项目（ZR2010BZ006）.

作者简介：牛淑妍(1963—)，女，教授.