Study On Photoelectric Properties Of Copper Nanocluster And Its Application In Food Safety Detection

Copper nanocluster as newly appearing material has been found use in detection of ion,hetero/electrochemical catalysis, biolabelling recently, where proteins, peptide,polythymine bases, organic molecules or microemulsion were used to help synthesize the cluster materials.The electrochemistry and electrochemiluminescence (ECL) of ligand-protected copper nanocluster (MPP, 2-mercapto-5-n-propylpyrimidine) were studied in this work. The redox behavior observed were originated from the couples of Cu8+/Cu82+, Cu8/Cu82+, Cu8/Cu8+under the potential window of -0.4?1.7V. From the electrochemical studies, we can conclude that copper nanocluster act as multi-electron donors or acceptors at a given potential due to trapping of holes and electrons within the metal core. ECL light emissions were observed under both annihilation and tripropylamine co-reactant conditions and only one excited state was involved in this ECL process and this excited state was also at the metal core. Theoretical investigation found that this excitation corresponds to an electron transfer from the metal core to the ligands. And the energy released from excited sate was approximate to be the LUMO?HOMO gap energy of the cluster. The ECL efficiency of the Cu cluster /TPA system was 0.74% in the presence of 5 mM TPA.Copper nanocluster as a novel fluorescene material has been used in fluorescene sensor. A method for the detection of papaverine was put forward in this work, which was based on the fluorescene quenching induced by papaverine. The QuEChERS (an acronym for quick, easy, cheap, effective, rugged, and safe) processing method with thin-layer chromatography was used to extract the papaverine when dentection of real sample. There were no papaverine found in hotpot condiments bought from the local supermarket. Add papaverine to one of the real samples form the spiked sample, the fluorescene intensity of copper nanocluster was quenched gradually as the concentration of papaverine in model sample increased in range of 0.4?1.0mg/kg.