基于纳米复合材料探针的新型棉线DNA室温快速检测装置的研究  

Nanocomposite Probe-based Novel Room Temperature Cotton Thread Device for Rapid Detection of DNA

作　　者：贾晓波 毛勋 JIA Xiao-Bo;MAO Xun(College of Science,Central South University of Forestry and Technology,Changsha 410004,China;College of Chemistry and Materials Science,Northwest University,Xi′an 710127,China)

机构地区：[1]中南林业科技大学理学院,长沙410004 [2]西北大学化学与材料科学学院,西安710127

出　　处：《分析化学》2021年第2期263-270,共8页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(No.21205094);陕西省青年百人计划项目(No.PR12011);中南林业科技大学人才引进项目(No.2017YJ037)资助。

摘　　要：建立了一种简单灵敏的棉线快速可视化DNA分析方法。采用碳纳米管/金纳米粒子复合材料修饰发夹型结构DNA探针构建信号探针,DNA探针两端各有8个A碱基,中间序列则与目标DNA链完全匹配,3′端修饰生物素,5′端修饰巯基,在甲氧襞因存在下,DNA探针因为两端的A碱基与甲氧襞因相互作用而形成发夹型结构。当样品中存在目标DNA分子时,纳米复合探针上的DNA发夹型结构被打开,释放出生物素分子,导致纳米复合探针被预先固定于棉线检测区域的链霉亲和素捕获,因而可以观察到棉线检测区域出现黑色条带。在优化条件下,检测区域条带颜色强度与目标DNA浓度在1~100 nmol/L范围内呈良好的线性关系,检出限为0.44 nmol/L(S/N≥3),灵敏度比采用纳米金探针的方法明显提高。此检测装置具有很强的单碱基突变识别能力,可实现与遗传型酪氨酸血症相关的DNA序列的快速可视化检测。A simple and sensitive cotton thread-based rapid visual DNA analysis method was developed.In this method,the reporter probe was constructed by using hairpin structure DNA sequence to modify carbon nanotube/gold nanoparticles nanocomposite(CNT/GNPs)for the first time.The DNA probe had 8 adenosines at both end,the middle part sequence of it was able to match with target DNA sequence quite well,and a biotin and thiol group were modified at 3′and 5′end respectively.The hairpin structure was formed due to the interaction between adenosines and coralyne.In the presence of target DNA molecules in sample,the hairpin structure of DNA on nanocomposite probe would be opened and the biotin group at 3′end of DNA sequence would be released and combined with streptavidin pre-immobilized on the test zone of cotton thread,forming a deep color band for visual detection of target DNA.Under the optimal conditions,the response of device was linear in the DNA concentration range of 1-100 nmol/L,and the detection limit was estimated to be 0.44 nmol/L.The sensitivity of the method was improved evidently comparing with the previous method of using gold nanoparticle probe.The biosensor also had strong ability to discriminate single base mutation,which realized rapid visual test of DNA sequence related to Hereditary tyrosinemia.

关 键 词：碳纳米管/金纳米粒子 DNA 可视化分析 酪氨酸血症 棉线 

分 类 号：TB33[一般工业技术—材料科学与工程] R318.08[医药卫生—生物医学工程]