将具有荧光特性的8-氨基喹啉和吡啶类试剂结合,并引入杂环三氮烯结构,合成了新型荧光试剂1-(8-喹啉)-3-(2-吡啶)-三氮烯(QPyT).其结构经元素分析、红外光谱和核磁共振谱证实.研究结果表明,在碱性介质中,该试剂在λex/λem=216nm/343nm处产生强荧光,并且能被Pb(Ⅱ)猝灭.据此建立了QPyT测定Pb(Ⅱ)的新型荧光分析法.该方法的线性范围为1.6×10^-7~1.2×10^-5mol/L,检测限为9.0×10^-8mol/L.将其应用于水中Pb(Ⅱ)的测定,结果令人满意.
Through combinination of 8-aminoquinoline with pydine through triazene group, a new fluorescent reagent 1 - ( 8-quinoline ) -3- ( pyridyl ) -triazene ( QPyT ) was synthesized. The product was confirmed by means of elemental analysis, ^1H NMR and infrared spectra. Its excitation and emission wavelengths were 216 nm and 343 nm in a basic medium, respectively. This new reagent reacted with Pb ( Ⅱ ) in a slightly basic medium to form a 1 : 1 complex, by which lead ion caused the fluorescence quenching of the new fluorescent reagent. The possible response mechanism of QPyT to Pb ( Ⅱ ) was discussed. The reaction showed a high selectivity and a high sensitivity for Pb( Ⅱ ). The new fluorescent reagent was used to determined trace Pb( Ⅱ ). The optimum analytical conditions for Pb( Ⅱ ) assay were established. Under these conditions, the linear range of Pb( Ⅱ ) was from 1.6×10^-7 to 1.2×10^-5 mol/L, with a detection limit 9.0×10^-8 mol/L. The method is selective, sensitive and simple. It was used for the determination of trace Pb ( Ⅱ ) in water sample with satisfactory results.