基于磁小珠-DNA-碳纳米管三明治组装体的光散射信号检测丙型肝炎病毒基因序列  

Light scattering detection of sequence-specific DNA related to the sepatitis C virus based on the sandwich-assembled structure of magnetic nanoparticle-DNA-carbon nanotubes

作　　者：杨晓溪[1] 李頔[2] 黄承志[1,2] 

机构地区：[1]发光与实时分析教育部重点实验室,西南大学药学院,重庆400715 [2]西南大学化学化工学院,重庆400715

出　　处：《科学通报》2013年第1期46-52,共7页Chinese Science Bulletin

基　　金：国家自然科学基金重点项目(21035005);国家重点基础研究发展计划(2011CB933600)资助

摘　　要：基于碳纳米管光散射和磁小珠易分离特性,以丙型肝炎病毒的一段相关基因序列为实例,通过检测磁小珠-DNA-碳纳米管组装形成的三明治结构产生的光散射信号建立了一种简便、快速、灵敏、免标记检测病毒基因序列的方法.由于单链DNA能通过–共轭缠绕在多壁碳纳米管表面,而双链不能,因而将丙肝病毒的一段相关DNA探针通过共价偶联修饰的磁小珠就能与多壁碳纳米管结合形成三明治结构,而当有靶物DNA存在时,因修饰在表面的DNA探针与靶物DNA进行特异性杂交阻碍三明治结构的形成.测定通过磁性分离三明治结构后上清液的光散射信号,发现在295nm处的光散射强度与1.0×10–64.0×10–8mol/L靶物DNA呈现良好的线性关系,检测限(3σ)为40nmol/L(n=10).In this contribution, we developed a simple, speedy, and sensitive label-free detection method of virus DNA sequence by taking hepatitis C virus （HCV） as an example, which is based on the measurements of light scattering signals of a sandwich structure formed by carbon nanotubes （CNTs）, DNA and magnetic nanoparticles （MNPs）. It has known that single-stranded DNA （ssDNA） can bind with multi-walled carbon nanotubes （MWCNTs） through π-π interaction, and neither can the double-stranded DNA （dsDNA）. Therefore, virus DNA probe-modified MNPs can easily bind with MWCNTs and forms some type of sandwich structure, while the presence of target DNA, owing to the specific hybridization of the probe DNA and target DNA, obstructs the formation of the sandwich structure. By measuring the light scattering signals of supernatant after separation by an external magnet, it was found that the intensity of the light scattering at 295 nm is proportional to the concentration of virus DNA in the range of 1.0×10^-6-4.0×10^-8 mol/L with a determination limit （3 δ） was 4.0×1^0-8 mol/L.

关 键 词：多壁碳纳米管 磁小珠 病毒 DNA 光散射 

分 类 号：TB383.1[一般工业技术—材料科学与工程] R373[医药卫生—病原生物学] R318.51[医药卫生—基础医学]