以"核-内壳-外壳"三层夹心结构上转换纳米材料(Sandwich Structure Upconversion Nanoparticles,SWUCNPs)为能量供体,异硫氰酸荧光素(FITC)为能量受体,构建了一种基于上转换荧光共振能量转移(UC-FRET)的纳米探针,其荧光猝灭效率高达95%。将该纳米探针用于水溶液中ClO-的检测,ClO-对配体的氧化使得能量供受体之间距离增大,上转换荧光恢复程度与ClO-的浓度呈线性关系,线性范围为0.02~3.4mmol/L,检出限为0.008mmol/L。实验结果表明该纳米探针特异性强、灵敏度高、结构灵活。
In this paper,a novel nanoprobe for ClO~- was constructed based on upconversion fluorescence resonance energy transfer(UC-FRET)from a sandwich-structure upconversion nanoparticles(SWUCNPs)with core-inner shell-outer shell architecture to the organic dye,fluorescein isothiocyanate(FITC).As a result,a maximum quenching degree of 95% was acquired.Upon the cleavage of the ligand by ClO-,the donor was separated from the acceptor resulting in the recovery of the donor emission.The fluorescence restoration of SWUCNPs obtained was linearly related to ClO- concentration ranging from 0.02 to 3.4 mmol/L with a detection limit of 0.008 mmol/L.The results show that the probe has strong specificity,high sensitivity and flexible structure.