利用巯基丙酸包覆的InP@ZnS 量子点(QDs)与Dured构建了一种检测DNA的荧光探针。在该探针中, 以环境友好型带负电的InP@ZnS量子点为荧光团, 与带正电的Dured通过静电结合, 构建了InP@ZnS QDs/Dured纳米荧光探针。通过荧光共振能量转移(FRET)机理, 量子点荧光被猝灭; 当DNA存在时, Dured与DNA的特异性结合使Dured从InP@ZnS QDs表面脱附, FRET过程被打断, InP@ZnS QDs荧光恢复, 以荧光“关-开”方式检测DNA。该探针检测DNA的线性范围为2.0～275.0 ng·L-1, 检测限为1.0 ng·L-1, 并可用于模拟生物生理条件下的DNA检测。

The fluorescent nanoprobe for the detection of DNA was established by utilizing mercaptopropionic acid coated InP@ZnS QDs and Dured. In this nanoprobe. The InP@ZnS QDs/Dured fluorescent nanoprobes were structured by electrostatic interactions between environment friendly, negatively charged InP@ZnS quantum dots and positively charged Dured, and then the fluorescence of InP@ZnS QDs/Dured was quenched through fluorescence resonance energy transfer (FRET). At presence of DNA, DNA and Dured were specific binding, which enable Dured removing from the surface of InP@ZnS QDs and achieving fluorescence recovery of InP@ZnS QDs. Thus, the detection of DNA was realized. The linear range of the InP@ZnS QDs/Dured fluorescent nanoprobes for DNA detection and the detection limit were 2.0-275.0 ng·L-1 and 1.0 ng·L-1, respectively. The InP@ZnS QDs/Dured fluorescent nanoprobes can be also used in rapid detection of DNA under simulated physiological conditions.