【摘要】 以巯基丙酸(HS—CH2CH2COOH)为稳定剂,水相合成了核壳型CdTePCdS量子点(QDs).当固定波长差为240 nm时,CdTePCdS量子点的同步荧光最大发射位于338 nm.基于DNA对量子点荧光的猝灭效应,将CdTePCdS量子点作为荧光探针建立了一种简便快速测定DNA的同步荧光分析法.详细研究了pH值、量子点浓度、离子强度、温度等条件对量子点同步荧光及DNA测定的影响.该方法测定ctDNA的线性范围为50.0~750.0μg/L,检出限为16μg/L,9次重复测定500μg/L ctDNA的相对标准偏差为2.0%.该方法用于合成样品的测定,结果满意.更多还原

【Abstract】 Nanometer-sized CdTePCdS fluorescent particles were synthesized in aqueous solution.A synchronous fluorescence method was developed for the rapid determination of DNA with functionalized water-soluble CdTePCdS core-shell quantum dots as a fluorescence probe,based on the synchronous fluorescence quenching of the QDs in the presence of DNA.The synchronous fluorescent spectra of CdTePCdS QDs were obtained by simultaneously scanning the excitation and emission monochrometers at a fixed Δλ of 240 nm.Under optimum conditions,the calibration graph is linear over the range 50.0-750.0 μg/L,with a detection limit of 16.0 μg/L.The relative standard deviation of 9 replicate measurements for 500.0 μg/L ctDNA is 2.0%.This method is simple,rapid and sensitive,and shows promise in the application of biologic systems.更多还原