N-N′-二-邻羧基苯基草酰胺荧光特性研究及应用

本文首次研究了酸度、温度对对称草酰胺:N-N’-二-邻羧基苯基草酰胺(OBBE)荧光特性的影响。测定了该试剂的荧光量子产率。发现在pH=8.0～9.5的H_3BO_3—NaOH缓冲介质中,硝酸根离子能使OBBE荧光强度定量猝灭。据此建立了同步荧光猝灭法测定硝酸根离子的新体系。OBBE的激发波长为210nm,发射波长为395nm。荧光猝灭值与NO_3~-在0.0028～0.16mg·L~(-1)呈线性关系,方法的检出限为0.0028mg·L~(-1)。实验了多种干扰离子的影响,用于水中硝酸根离子的测定,结果满意。

Fluorescence Property of OBBE and Its Application

The effects of acidity and temperature on the fluorescent characteristics of N-N-bis-(O-Carboxylphenyl)-Oxamide (OBBE) have been studied in details. And the quantum efficiency of fluorescence has been measured. In a pH 8-9.5 buffer medium of H3BO3-NaOH, OBBE has a maximum excitation wavelength at 210 nm and a maximum emission wavelength at 395 nm. The nitrate reacts with OBBE and quenches the fluorescent intensity of OBBE. Thus a new sensitive method using the quenching of synchronous fluorimetry has been developed for the direct determination of nitrate in water. The linear calibration curve was obtained in the range of 0.0028 and 0.16 mg.L-1, the detection limit was 0.0028 mg.L-1. The proposed method has been applied to the determination of nitrate in water with satisfactory results.