3,5-二溴水杨醛缩氨基吡啶的合成及其应用于萃取荧光法测定微量季铵盐

Extraction-Fluorimetric Determination of Quaternary Ammonium Salts in Water Using 3,5-Dibromosalicylidene-α-amino-pyridine

本文合成了新荧光试剂3，5-二溴水杨醛缩氨基吡啶，用元素分析、红外光谱证实了新化合物的结构。并且将此试剂用于萃取荧光法测定水中微量季铵盐。研究了反应条件．探讨了反应机理。所提出的方法灵敏度好，干扰少。

A new fluorescent reagent 3, 5-dibromosalicylidene-α-amino-pyridine was synthesized by reacting 3, 5-dibromosalicylaldehyde with α-amino-pyridine and characterized with elemental analysis and IR. It is used for the determination of trace quaternary ammonium salts in water. The method is based on the formation of a stable ion pair, which is extractable into chloroform from NaHCO3-Na2CO3 solution after shaking for 3 minutes and is fluorigenic. The amount of quaternary ammonium salt is directly proportional to the fluorescence intensity. The fluorescence excitation and emission wavelengths of the ion pair are at 420 nm and 505 nm, respectively. The optimium pH range is from 9. 0 to 10. 0. The linear determination range is from 0 to 1. 5 ×10-4 mol/L (zepheramince) or from 0 to 2.0×10-4mol/L(geraminum). The molar ratio of quateranry ammonuim salt to reagent is found to be 1: 1. The proposed method has been used for the determination of trace zephiramine and geraminum in water with satisfactory results.