石英谐振式基因传感器芯片表面探针修饰电极的构建

Construction of electrode modified with probe at the surface of quartz oscillation gene sensor chip

目的 在石英谐振式传感器芯片表面构建DNA探针修饰的金膜电极 ,以便用于进一步的研究需要。方法 利用自组装单分子层 (self-assembe1edmonolayer,SAM)技术将 5’端带有巯基的DNA探针共价交联到石英谐振式传感器芯片的金膜表面 ,利用循环伏安计 (circledvoltammeter,CV) ,扫描隧道显微镜 (scanningtunnelmicroscopy,STM )观察探针交联前后金膜表面电化学表征及微观结构的改变。结果 CV测量结果显示随着探针在金膜表面的吸附 ,界面电容减小。STM扫描结果更是直观地显示探针非常均匀、规整地在金膜电极表面形成一层SAM。结论 利用SAM技术可以很好地将DNA探针固定在石英谐振式传感器芯片金膜表面。

Objective To construct of electrode modified with DNA probe at the surface of gold membrane of sensor chip for further medical research. Methods DNA probe with thiol group in 5' terminus was covalently linked to the surface of gold membrane by self-assembled monolayer(SAM) technique, Changes of the electrochemical parameters and microscopic construction in gold membrane were observed with cireled voltammeter (CV) and scanning tunnel microscopy(STM). Results Results measured by CV showed that surface electric capacity decreased following the absorption of DNA probe on the surface of sensor chip. And a SAM on the surface of gold membrane formed very even by DNA probe was directly observed by STM scanning.Conclusion DNA probe was definitely immobilized at the surface of gold membrane of quartzoscillation sensor chip by SAM.