新荧光试剂双(2-苯并噻唑重氮氨基)-3,3′,5,5′-四甲基联苯的合成及其分析应用

将3,3′,5,5′-四甲基联苯胺和苯并噻唑类试剂结合, 并引入杂环三氮烯结构, 合成了新荧光试剂双(2-苯并噻唑重氮氨基) 3,3′,5,5′-四甲基联苯(BBTDTMB), 其结构经红外光谱、 核磁共振谱和元素分析证实. 研究结果表明, 在碱性介质中, 该试剂在λex/λem=342 nm/420 nm处产生强荧光, 并且Ag(Ⅰ)对其荧光有很好的猝灭作用, 因而建立了BBTDTMB测定Ag(Ⅰ) 的新荧光分析方法. 该方法的线性范围为1.0～240 μg/L, 检测限为 0.5 μg/L, 应用于人发、 茶叶中的Ag(Ⅰ) 的测定, 结果令人满意.

Synthesis and Application of Bis(2-benzothiazolydiazoamino)-3,3′,5,5′-Tetramethylbiphenyl

With the aid of combining 3,3′,5,5′-tetramethylbiphenyl with benzothiazole through triazene group, a new fluorescent reagent bis(2-benzothiazolydiazoamino) 3,3′,5,5′-tetramethylbiphenyl(BBTDTMB) was synthesized. The product was confirmed by means of elemental analysis, 1H NMR and infrared spectra. Its excitation and emission wavelengths were 342 nm and 420 nm in a basic medium, respectively. This new reagent reacts with Ag(Ⅰ) in a slightly basic medium to form a 1∶2 complex, by which silver ion causes the fluorescence quenching of the new fluoresent reagent. The reaction showed a high selectivity and a high sensitivity for Ag(Ⅰ). A new spectrofluorimetric method for the determination of trace Ag(Ⅰ) with this reagent was developed. The linear range of determination for Ag(Ⅰ) was 1.0—240 μg/L with a detection limit of 0.5 μg/L. The method is a selective, sensitive, and simple analytical procedure, and was used for the determination of trace Ag(Ⅰ) in hair and tea with satisfactory results.