摘要
目的建立以CdTe/CdS-RhB荧光共振能量转移体系为荧光探针,设计出一种快速、超灵敏且高选择性的检测Pb(Ⅱ)含量的方法。方法研究CdTe/CdS和罗丹明B(受体)之间FRET的最佳条件利用,Pb2+能对能量转移体系中CdTe/CdS的荧光峰强产生猝灭作用从而测定Pb2+的含量。结果在3.85×10-10～9.62×10-9mol.L-1线性关系良好,相关系数r为0.997 5。9组浓度为3.85×10-9mol.L-1的Pb(Ⅱ)对量子点-罗丹明体系荧光猝灭的相对标准偏差(RSD)为0.32%。将该方法用于测定菠菜和柑橘叶中Pb(Ⅱ)的含量分别为69.6和55.2μmol.kg-1,与火焰原子吸收光谱法比较无显著性差异。结论该体系作为荧光探针测定Pb(Ⅱ)简便经济可行,灵敏度高,选择性好。
Objective To establish a fast,ultra-sensitive and highly selective method for Pb（Ⅱ） fluorescent probes with CdTe/CdS QDs-rhodamine B system.Methods The optimum conditions for fluorescence resonance energy transfer between CdTe/CdS QDs and rhodamine B were studied.According to the phenomenon that Pb2 ＋quenched the fluorescence of CdTe/ CdS in the energy transfer system,we finally determined the content of Pb2 ＋.Results The extent of fluorescence quenching was proportional to the trace concentration of Pb（Ⅱ） from 3.85×10-10 to 9.62×10-9mol.L-1 with a correlation coefficient of 0.997 5.The relative standard deviation of 0.32%（38.5×10-10mol.L-1,n = 9） was obtained.The proposed method was successfully applied in the analysis of Pb（Ⅱ） in spinach and citrus leaves with QDs-RhB.The contents of Pb（Ⅱ） were 69.6 and 55.2 μmol.kg-1,respectively.The results were reliable,with no difference compared with those of atomic absorption spectrometry.Conclusion The system,as a fluorescent probe of Pb（Ⅱ）,is simple,economical,sensitive and selective.
出处
《中南药学》
CAS
2013年第6期413-417,共5页
Central South Pharmacy
关键词
荧光共振能量转移
量子点
Pb(Ⅱ)
fluorescence resonance energy transfer
quantum dots
Pb（Ⅱ）
