【摘要】 基于直立碳纳米管上的大面积金粒子构建了新型的电化学DNA生物传感器,用于急性早幼粒细胞白血病PML/RARα融合基因的检测。首先在直立碳纳米管电极表面溅射金粒子,采用自组装方法将巯基修饰的单链DNA固定到电极上,将氨基修饰的单链DNA和羧基化的Cd Te量子点通过酰胺缩合反应生成Cd Te修饰的DNA探针,通过与目标DNA的双杂交反应形成三明治结构,利用差分脉冲阳极溶出伏安法检测电极表面捕获的Cd Te量子点,从而对DNA进行定量分析。结果表明,电极上Cd²⁺峰电流与目标DNA浓度(1.0×10^-121.0×10^-8mol/L)的对数值呈线性关系,线性方程为i_pa（μA）=1.626+0.132lg C（mol/L）（R=0.996）,检出限为4.0×10^-13mol/L（3σ）。传感器表现出良好的重现性和稳定性。更多还原

【Abstract】 A novel electrochemical DNA biosensor was fabricated based on the large area of gold particles on the aligned carbon nanotubes for the detection of promyelocytic leukaemia / retinoic acid receptor α（ PML /RARα） fusion gene in acute promyelocytic leukemia. Firstly, the thiol-modified single-stranded DNA（ ss DNA,probe 1） was immobilized on the gold particles sputtered on the aligned carbon nanotubes electrode by self-assembly technique. Then,amino-modified ss DNA and carboxyl-modified Cd Te quantum dots（ QDs）were combined to get Cd Te-modified DNA probe through an amidization reaction. After hybridization with target DNA,a sandwich-type assay structure was formed. Finally,the Cd Te quantum dots captured on the electrode surface were detected by differential pulse anodic stripping voltammetry. The change of peak current of Cd²⁺on the electrode was found to be linear with the logarithm of target DNA concentration in the range of1. 0 ×10^-12mol / L to 1. 0 ×10^-8mol / L. The Linear equation was i_pa（ μA） = 1. 626+0. 132 lg C（ mol/L）（ the correlation coefficient R was 0. 996） and the detection limit was 4. 0 ×10^-13mol / L（ 3σ）. The fabricated DNA biosensor exhibited excellent reproducibility and stability.更多还原