酰胺基双Schiff碱仲胺荧光探针的合成及对Pb^(2+)的识别研究

Synthesis and selective recognition of Pb^(2+) ions by bis-Schiff Base amine containing amaide bridge fluorescent probe

以2,6-吡啶二甲酸、乙二胺、邻甲氧基苯甲醛等为原料,经缩合反应,还原反应,设计合成了双Schiff碱仲胺荧光探针(L),并通过IR、UV、^(1)H NMR、MS等对其结构进行了表征。考察了其荧光光谱特性、与数种常见金属离子的选择性,结果表明:荧光探针对金属Pb^(2+)离子的响应最好,荧光强度增强最多。探针L的荧光强度与Pb^(2+)浓度呈现良好的线性关系,相关系数为R^(2)=0.99844,检出限为3.1164×10^(-6)mol·L^(-1);通过络合比实验表明探针L与Pb^(2+)离子的络合比1∶1,络合常数为7.2727×10^(7)(mol/L)^(-1),初步应用于水体样本中Pb^(2+)的检测,回收率在97.73~102.93%。

A fluorescent probe(L)of bis Schiff base secondary amine ligand was designed and synthesized from 2,6-pyridinedicarboxylic acid,ethylenediamine and o-methoxybenzaldehyde by condensation reaction and reduction reaction.Its structure was characterized by IR,UV,^(1)HNMR and MS.The fluorescence spectra and selectivity to several common metal ions were investigated,and the results showed that the fluorescent probe(L)had the best response to metal Pb^(2+) ions and the fluorescence intensity was the most enhanced.A good linear work curve with R^(2)=0.99844 was achieved in the linearity range from 0 to 50μmol·L^(-1) of Pb^(2+),and the limit of detection was 3.1164 umol·L^(-1).A 1∶1binding ratio of L/Pb^(2+) for the complex was obtained by Job's plot and fluorescence titration experiments,and the Pb complex instant was 7.2727×10^(7)(mol/L)^(-1).It was used for the determination of trace Pb^(2+) in environmental water with the recovery of 97.73~102.93%.