基于网状硒化钼和杂交链式反应高灵敏检测DNA

Highly Sensitive Determination of DNA based on Net-like Molybdenum Selenide and Hybridization Chain Reaction

用水热法合成了网状硒化钼纳米,将其和纳米金修饰于玻碳电极表面,固定上DNA探针后结合杂交链式反应构建了一种新型信号放大型电化学传感器,用于特定DNA序列的超灵敏检测.硒化钼纳米片具有好的导电性能和大的比表面积,结合杂交链式反应的信号放大作用,可显著提高检测灵敏度.用于DNA检测,其线性范围为1.0×10-10~1.0×10-14mol/L,信噪比等于3时,检出限为8×10-15mol/L.该传感器可区分三碱基错配的DNA和单碱基错配的DNA,具有较高的选择性.

Net-like molybdenum selenide was prepared by a hydrothermal method. A novel DNA electrochemical sensor was fabricated by modifying molybdenum selenide and Au nanoparticles on glassy carbon electrode and coupled with hybridization chain reaction for ultrasensitive determination of specific DNA sequences. The molybdenum selenide nanosheets have good electro-conductivity and large specific surface area,which can amplify the detection signal when couple with hybridization chain reaction. For DNA detection,the linear range of the developed assay was 1. 0 × 10- 10~ 1. 0 × 10- 14 mol / L with a low detection limit of 8. 0 × 10- 15 mol / L（ S / N = 3）. This sensor showed a good specificity for the target DNA detection,with the capability to discriminate single-base-pair mismatched DNA mutation and three-base-pair mismatched DNA mutation.