Ratiometric ultrasensitive fluorometric detection of ascorbic acid using a dually emitting CdSe@SiO2@CdTe quantum dot hybrid
Ratiometric ultrasensitive fluorometric detection of ascorbic acid using a dually emitting CdSe@SiO2@CdTe quantum dot hybrid
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使用双发射 CdSe@SiO2@CdTe 量子点混合体对抗坏血酸进行比率超灵敏荧光检测
DOI：
10.1007/s00604-017-2557-9
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发表时间：
2018-01-01
影响因子：
5.7
通讯作者：
Hu, Jun
中科院分区：
文献类型：
--
作者：
Wang, Jing;Peng, Xiao;Hu, Jun
设计了一种双发射量子点纳米杂化体，用于抗坏血酸（AA）的两波长荧光测定。该纳米复合物由红色发光CdTe量子点（QDs）与含有绿色发光CdSe量子点的二氧化硅纳米颗粒表面共价连接而成。在cdteo3和TeO2的氧化作用下，加入kmno4后，红色CdTe量子点的荧光（峰值在616 nm处）首先被淬灭。添加AA后，由于表面CdTeO3/ teo2还原形成CdTe，红色荧光得以恢复。相比之下，绿色发光CdSe量子点的绿色荧光（峰值在522 nm处）保持不变，其强度可作为参考信号。这两种量子点都可以在380 nm处被光激发。在增加AA的添加量时，可以观察到荧光（从绿色到橙红色）的明显转变。在最佳条件下，在0.1 ~ 5.0 μM AA浓度范围内，红、绿荧光强度之比线性增加，检出限低至35 nM。该方法成功地应用于加标果汁样品中AA的定量分析。设计了一种新型双发光CdSe@SiO2@CdTe纳米杂化物，用于比例超灵敏荧光法检测果汁样品中的抗坏血酸。
A dually emitting quantum dot nanohybrid was designed for the fluorometric 2-wavelength determination of ascorbic acid (AA). The nanohybrid consists of red-emitting CdTe quantum dots (QDs) covalently linked to the surface of silica nanoparticles containing green-emitting CdSe QDs. The fluorescence of the red-emitting CdTe QDs (peaking at 616 nm) is first quenched by addition of KMnO4due to oxidation under formation of CdTeO3and TeO2. On addition of AA, the red fluorescence is restored due to the reduction of surface CdTeO3/TeO2to form CdTe. The green fluorescence of the green-emitting CdSe QDs (peaking at 522 nm), in contrast, remains constant and its intensity serves as a reference signal. Both kinds of QDs can be photoexcited at 380 nm. An easily distinguishable transition in fluorescence (from green to orange-red) can be observed on increasing the amount of added AA. Under optimal conditions, the ratio of the intensities of the red and the green fluorescence increases linearly in the 0.1 to 5.0 μM AA concentration range, and the detection limit is as low as 35 nM. The assay was successfully applied to the quantitation of AA in (spiked) fruit juice samples.Graphical abstractA new dually emitting CdSe@SiO2@CdTe nanohybrid was designed for ratiometric ultrasensitive fluorometric detection of ascorbic acid in fruit juice samples.