催化碘酸钾氧化异硫氰酸荧光素荧光猝灭法测定痕量硒

Determination of Trace Selenium by Fluorescence Quenching Method Based on Catalyfic Oxidiation of Fluorescein Isothiocyanate by Potassium Iodate

中文关键词:  硒,异硫氰酸荧光素, 催化荧光猝灭法

英文关键词:Selenium,Fluorescein isothiocyanate,Catalytic fluorescence quenching method

中文摘要:

      基于异硫氰酸荧光素（FITC）可发射强而稳定的荧光信号，KIO₃能氧化FITC而发生荧光猝灭， Se(Ⅳ)使FITC的荧光强烈猝灭，Se(Ⅳ)的含量与ΔF值呈线性关系，建立催化KIO₃氧化FITC荧光猝灭法测定痕量硒的新方法.方法的线性范围为0.012～2.000×10^－15 g Se(Ⅳ)/mL，工作曲线回归方程ΔF = 1.18＋72.74C_Se(Ⅳ)(×10^－15 g/mL)（n=6，r=0

英文摘要:

      Fluorescein isothiocyanate (FITC) can emit strong and stable fluorescence，KIO₃ can oxidize FITC and quench the fluorescence signal，Se(Ⅳ) can strongly quench the fluorescence signal of FITC, and the content of Se(Ⅳ) is directly proportional to ΔF. Based on the facts above，a new fluorescence quenching method for the determination of trace Se(Ⅳ) has been established based on the catalytic oxidiation of FITC by KIO₃. The linear range of this method was 0.012~2.000×10^－15 g Se(Ⅳ)/mL，with a detection limit of 2.1×10－18 g/mL, n=11，the regression equation of working curve was ΔF=1.18＋72.74C_Se(Ⅳ)(×10^－15 g/mL)，n=6，r=0.9997. Samples containing 0.012 and 2.000×10^－15 g Se(Ⅳ)/mL respectively were measured for seven times and the RSDs were 2.8% and 3.5%. It has been satisfactorly applied to the determination of trace Se in real samples and has used to diagnose and forecast human disease. The mechanism for the determination of trace Se(Ⅳ) by catalytic fluorimetry was also discussed.