基于二硫化钼交流阻抗适体传感器对三磷酸腺苷的无标记检测

摘要

An AC impedance aptasensor has been developed for label-free adenosine triphosphate (ATP) determination based on gold nanoparticles-decorated MoS2 (AuNPs@ MoS2 ) nanocomposite .AuNPs@ MoS2 nanocomposite has been synthesized by using MoS2 self-reduction ability .The ATP aptamer (ATPA) was immobilized on the surface of AuNPs@ MoS2 modified electrode via Au-S ,which can selectively detect ATP by using K3 Fe(CN)6 and K4 Fe(CN)6 as the electrochemical indicator .The structure of ATPA is switched with the ATP addition ,resulting in the electron transfer is blocked and the resistance value increases .The ex-perimental results show that the linear range of the MoS2-based sensor is 10 nmol/L-1 mmol/L with a detection limit of 1 nmol/L .Moreover ,the sensor can efficiently distinguish ATP ,CTP ,GTP and UTP ,suggesting the sensor has high sensitivity and good selectivity .This proposed biosensor can offer a potential application for other biomolecules detection .%为了实现对三磷酸腺苷（ATP）无标记、高灵敏地检测，构建了基于二硫化钼的交流阻抗适体传感器。利用二硫化钼自身的还原性成功合成了金纳米颗粒功能化二硫化钼（AuNPs＠ MoS2）纳米复合材料，并通过Au-S键将ATP核酸适体组装到AuNPs＠ MoS2修饰电极表面。当核酸适体与ATP结合后，其构型发生变化，将会阻碍电化学信号分子K3Fe（CN）6和K4Fe （CN）6与修饰电极间的电子传递，使该适体传感器的电阻变大。在最优条件下，该传感器检测ATP的线性范围为10 nmol／L～1 mmol／L ，检出限为1 nmol／L ，并能很好地区分ATP与CTP、GTP和UTP ，表明该传感器具有较高的检测灵敏度和良好的特异性。该传感器的成功构建，为其他生物分子的检测提供了新的思路。