双［3－（4－溴苯）重氮氨基］－联苯的合成及分析应用

摘要

With the aid of combining of benzidine with 4-brominoaniline through triazene group, a new fluorescent reagent bis [3-(4-Bromobenzene) diazoamino]– biphenyl ( BBDB) was synthesized and confirmed by means of infrared spectra. A chelate complex was formed by the reaction between BBDB and Pb (Ⅱ) in a weak basic medium, which resulted in the enhancement of fluorescence. The possible response mechanism of BBDB to Pb (Ⅱ) was discussed. A new spectrofluorimetric method for the determination of trace Pb (Ⅱ) with this reagent was developed. The excitation and emission wavelengths of BBDB / Pb (Ⅱ) system were 340 and 419 nm in a basic medium respectively. Under optimal conditions, a linear response to mercury was obtained in the concentration range from 2.5×10-7to 9.0×10-5 mol /L, and the detection limit was 1.18×10-7 mol /L .%将联苯胺和4－溴苯胺结合，并引入杂环三氮烯结构，合成了新型荧光试剂双[3－（4－溴苯）重氮氨基]－联苯（简称BBDB ）。其结构经红外光谱分析初步证实。研究结果表明，在碱性介质中，该试剂与Pb （Ⅱ）形成1：1的络合物，并在λex／λem＝340 nm／419 nm处产生荧光增强作用。据此建立了三氮烯测定Pb（Ⅱ）的新型荧光分析法。该方法的线性范围为2�5×10－7～9�0×10－7 mol／L，检出限为1�18×10－7 mol／L。