罗丹明B多层荧光纳米微球对Hg^2＋的检测

Multilayer fluorescence nanosphere sensor for the detection of Hg^(2+) based on rhodamine derivative

利用水热法合成了掺杂锌的碲化镉量子点(CdTe∶Zn QDs),并采用反相微乳法将SiO_2包覆在量子点表面形成多层SiO_2纳米微球。通过接枝方法将罗丹明B衍生物连接在硅球上,利用Hg^(2+)可以使罗丹明B衍生物的螺环结构发生开环反应并产生荧光增强这一特性,构建了荧光共振能量转移(FRET)的比率探针,并成功实现了对水溶液中Hg^(2+)的比率检测。结果表明,该探针在波长为521nm和577nm时对Hg^(2+)具有良好的灵敏度和选择性,检测限是0.5μM。

Zn doped CdTe quantum dots（CdTe∶Zn QDs）were synthesized via hydrothermal procedure and SiO2 was coated on the surface of quantum dots by a reverse microemulsion method to form multilayered silica nanospheres.Further the rhodamine B derivative was connected to the silicon sphere by grafting method.Hg^2＋,which can not only induce the ring-opening reaction of rhodamine B derivative,but can significantly enhance the fluorescence intensity.Based on this mechanism,the probe of fluorescence resonance energy transfer（FRET）was successfully constructed and the proposed ratio probe was efficiently applied to the determination of Hg^2＋ in aqueous solution.The results showed that the probe had good sensitivity and selectivity to Hg^2＋ at the wavelength of 521 nm and 577 nm,and the limit of detection was 0.5μM.