基于核酸适体和纳米材料构建电化学生物传感器用于多巴胺的检测

该文探究了一种基于核酸适体和纳米金包四氧化三铁（Au@Fe，041纳米粒子所构建的新型电化学生物传感器用于多巴胺（DA）的检测。首先，在玻碳电极（GCE）表面电沉积一层纳米金（nano—Au）用于多巴胺适体（DBA）的固定。然后HT做为封闭剂以减少非特异性吸附。接着通过与DBA的特异性结合将DA固载于电极表面。在EDC／NHS作用下，生物素（Bio）的羧基与DA的氨基结合，最后通过生物素与亲和素特异性识别作用将含有电化学活性物质硫堇的纳米复合材料固定于电极表面，制得夹心型的适体传感器。在最优条件下．该传感器对0．001nmol／L-100nmol／LDA的检测具有良好的电流响应，检出限0．33pmol／LfS／N=31。该适体传感器具有操作简单、操作简便、选择性好、灵敏度高、检测范围广、检出限低的优点。

A novel electrochemical aptasensor for sensitive detection of dopamine based on nucleic acid aptamer and nanomaterials

In this work, a novel strategy was constructed based on nucleic acid aptamer and nanomaterials for the sensitive detection of dopamine （DA）.The thiolated dopamine binding aptamer （DBA） were firstly immobilized on the gold nanoparticles （nano-Au） modified glassy carbon electrodes （GCE）. In the presence of target DA, the DBA could catch the DA onto the electrode surface. The anchored DA was then derivatized with biotin for the attachment of the conjugates which contain the electron media thionine to contrast a sandwich-type aptasensor. Under the optimal conditions, a wide detection range from 0.001 nmol/L to 100 nmol/L and a low detection limit of 0.33 pmol/L （defined as S/N = 3） for DA were obtained. In addition, the sensor exhibited the advantages of simple operation, easy to operate, good selectivity, high sensitivity.