中文摘要：

CdTe量子点表面包覆双硫腙,由于双硫腙与CdTe量子点之间发生荧光共振能量转移使得CdTe量子点荧光猝灭,铜的加入与双硫腙形成双齿螯合物,使得CdTe量子点荧光能量转移被阻止,CdTe量子点荧光强度得以恢复,由此建立了一种荧光开关测定痕量铜的新方法。在最佳条件下,0.5mL双硫腙@CdTe量子点（Dit@CdTe）,1.5mL pH 7.5的Tris-HCl缓冲溶液中加入不同浓度的Cu2＋,放置10min,于激发波长/发射波长为431nm/591nm下进行荧光测定,荧光增强强度与Cu2＋浓度在0.01～10.0μmol/L范围内呈良好线性关系,相关系数为0.990 3,检出限为0.004μmol/L。方法用于实际水样中铜的测定,相对标准偏差小于6.8%,回收率在97%～105%之间,并且测定结果与电感耦合等离子体质谱法（ICP-MS）测定结果一致。

英文摘要：

The surface of CdTe quantum dots was coated by dithizone.The fluorescence quenching of CdTe occurred due to fluorescence resonance energy transfer between dithizone and CdTe quantum dots.The fluorescence resonance energy transfer was prohibited due to the formation of bidentate chelate after copper ion was added,then the fluorescence intensity of CdTe quantum dot was recovered.Based on this,a new determination method of trace copper by fluorescent switch was established.Under the optimal conditions,copper ions of different concentration were added into the solution which was composed of 0.5mL of dithizone@CdTe quantum dots（Dit@CdTe）,1.5mL of Tris-HCl buffer solution（pH 7.5）.After standing for 10min,the fluorescence intensity of solution was measured at 431nm/591nm（excitation wavelength/emission wavelength）.The enhanced fluorescence intensity showed good linear relationship to Cu2＋concentration in the range of 0.01-10.0μmol/L with correlation coefficient of 0.990 3.The detection limit was 0.004μmol/L.The proposed method was applied to the determination of copper in actual water sample.The relative standard deviation was less than 6.8%,and the recovery was 97%-105%.The determination results were consistent with those obtained by inductively coupled plasma mass spectrometry（ICP-MS）.