摘要
采用电沉积法制备了铁氰化镍(NiHCF)氧化还原电化学探针,以金纳米粒子(GNPs)为固定核酸适配体的载体构建了非标记型测定凝血酶(TB)和腺苷(AD)的核酸适配体传感器.采用循环伏安法(CV)和SEM对NiHCF膜进行了表征;利用电化学阻抗(EIS)对传感器的组装过程进行了监测;用CV和差分脉冲伏安法(DPV)对该传感器的电化学行为进行了研究.该传感器对凝血酶的检测在1.0 fg mL-1～1.0μg mL-1范围内成良好的线性关系,相关系数为0.997,检测限为0.27 fg mL-1;对腺苷的检测在1.0 fg mL-1～1.0 ng mL-1范围内成良好的线性关系,相关系数为0.997,检测限为0.36fg/mL.该传感器制备简单,灵敏度高,抗干扰能力强.
A highly sensitive label-free electrochemical aptasensor has been constructed for the electrochemical detection of thrombin（TB） and adenosine（AD）,where nickel hexacyanoferrate（NiHCF） redox probes were immobilized on the electrode surface by electrodeposition.Through the strong interaction between CN-（NiHCF） and gold nanoparticles（GNPs）,GNPs were assembled on the NiHCF modified electrode for the immobilization of thiolated thrombin aptamer（APT-1）.GNPs effectively provided many binding sites for the assembly of thiol derivated aptamer and favorable microenvironment for the aptasensor,which greatly improves the performance of the aptasensor.Then,APT-1 was hybridized with adenosine aptamer（APT-2）.For the detection of thrombin,the modified electrode was immersed in the thrombin solution with different concentrations.The APT-1 on the modified electrode could bind the TB onto the electrode surface,which resulted in a barrier for electron-transfer,leading to decrease of the current of redox probe NiHCF.For adenosine detection,the procedure was analogous to thrombin detection.Cyclic voltammetry and SEM were used to characterize the electrochemical behaviors and the morphology of NiHCF film.Electrochemical impedance spectroscopy was used to monitor the self-assembly process of the aptamer biosensor.The electrochemical behavior of the aptamer biosensor was studied by the cyclic voltammetry and differential pulse voltammetry for the detection of TB and AD.The biosensor shows a good linear range of 1.0 fg mL-1～1.0 μg mL-1 for thrombin,R=0.997,with a detection limit of 0.27 fg mL-1;the biosensor shows a good linear range of 1.0 fg mL-1～1.0 ng mL-1 for AD,R=0.997,with a detection limit of 0.36 fg mL-1.A comparison of the analytical performance such as the sensitivity,the linear range,the detection limit,redox probe and electrochemical technique between the developed aptasensor and other previously reported methods in the literatures has been performed.The biosensor has simple preparation procedu
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2013年第3期451-456,共6页
Acta Chimica Sinica
基金
国家自然科学基金(No.21065004)
江西省自然科学基金(No.2009GQH0022)
江西省教育厅科技项目(No.GJJ12304)资助~~
