将具有荧光特性的杂环8-氨基喹啉和吡啶类试剂结合,并引入三氮烯结构,合成了新型荧光试剂1-(8-喹啉)-3-(3,5-二溴-2-吡啶)-三氮烯(QBPyT)。其结构经元素分析、红外光谱、核磁共振波谱证实。研究结果表明,在pH 9.5硼酸-氢氧化钠缓冲溶液的介质存在下,该试剂在λex/λem=248 nm/496 nm处产生强荧光,并且能与铅(Ⅱ)形成配合物从而使荧光增强。据此建立了三氮烯测定铅(Ⅱ)的新型荧光分析法。铅的浓度在5.0×10-7~1.2×10-5mol·L范围内与其荧光强度呈线性关系,检出限(3S/N)为9.5×10-8mol·L。将其应用于水样中铅(Ⅱ)的测定,测得回收率在92.6%~94.0%之间,测定值的相对标准偏差(n=5)小于3.5%。

By connecting the triazene structure with the heterocyclic fluorescent reagents of quinoline and pyridine, a new fluorescence reagent of 1-(8-quinoline)-3-(3,5-dibromo-pyridine)-triazene (QBPyT) was synthesized and identified by elemental analysis, IRS and NMR. Strong fluorescence at the wavelengths of 248 nm (λex) and 496 nm (λem) was emitted by this reagent in a borate buffer medium of pH 9.5, and an enhancement of fluorescence was observed in the presence of Pb(Ⅱ) ion due to the formation of a coordination complex between Pb(Ⅱ) and QBPyT. Linear relationship between the magnitude of increase in fluorescence intensity and concentration of Pb(Ⅱ) was obtained in the range of 5.0×10-7-1.2×10-5mol·L with detection limit (3S/N) of 9.5×10-8mol·L. The proposed method was used in the analysis of water samples, giving RSD′s (n=5) less than 3.5%, and using these samples as matrixes, recovery was tested, the values of recovery found were ranged from 92.6% to 94.0%.