Fluorescent Probes Based On Catalysis With Noble Metal Nanoclusters

As a kind of novel luminescent nanomaterials,noble metal nanoclusters possess various merits,including strong photoluminescence,good photostability,excellent water solubility and biocompatibility,which have attracted much attention and are widely used as fluorescent probes for substance analysis and detection.In this dessertation,two kinds of fluorescent noble metal nanoclusters were systhesized,which respectively functioned as fluorescent probes for copper ion and alkaline phosphatase detection with the help of catalysis.Copper ion can cause the fluorescence quenching of bovine serum albumin-stabilized gold nanoclusters,based on which only low sensitivity can be obtained for copper ion detection.However,it catalyzed the reaction between persulfate and iodide ions,and rapidly produced much iodine,which could effectively quench the gold nanoclusters’ fluorescence.Therefore,we combined this inorganic catalytic reaction with gold nanoclusters for copper ion detection with high sensitivity,which showed a linear range as 0.8-80 nM and the limit of detection as 0.33 nM.As an important enzyme regulating biological process,alkaline phosphatase has become a health index in clinical diagnosis.Based on thiol as an effective fluorescence quencher of silver nanoclusters protected by polyethyleneimine,we established the dephosphorylation of thiophosphate under the catalysis of alkaline phosphatase,which produced much thiol.Thus,alkaline phosphatase detection with high sensitivity was realized with a linear range as 0.08-2 U/L and the limit of detection as 0.02 U/L.This method was successfully applied to real sample analysis.