一种选择性检测SO2的荧光增强型探针的合成

摘要

As an important gas signal molecule, sulfur dioxide(SO2) has attracted increasing attention in recent decades.It has been revealed that SO2 and its derivatives are closely associated with various symptoms and diseases including cancer, cardiovascular diseases, neurological disorders and respiratory problems.Hence, developing analytical methods that could realize concentration determination of SO2 and its derivatives are highly needed.In this work, we reported a novel turn-on fluorescent probe(3) for selectivie sensing of SO2 derivatives based on the conjugate of benzo[e]indolium and pyrrole.The intermediate 2 was prepared by using 1,1,2-trimethyl-1H-benz[e]indole and iodomethane as raw materials.3 was synthesized via condensation of 2 with 5-formyl-2,4-dimethyl-1H-pyrrole-3-carboxylic acid.The structure was characterized by 1H NMR, 13C NMR and HR-MS.3 exhibited excellent selectivity for SO2 over other anions and reductive sulfurs.With addition of sulfur dioxide, the emission intensity at 450 nm increased accordingly, and the emission intensity was linear function with the sulfur dioxide concentration over the range from 0 to 100 μmol·L-1(R2=0.997).%SO2作为一种重要的气体信号分子,其浓度异常与癌症、心血管疾病、神经系统疾病有关,因此有必要发展一种检测SO2的分析方法.本文以1,1,2-三甲基-1H-苯并[e]吲哚和碘甲烷为原料合成中间体2;2与2,4-二甲基-5-醛基-1H-吡咯-3-羧酸经缩合反应合成了一个基于苯并吲哚和吡咯共轭的荧光增强型探针(3),其结构经1H NMR, 13C NMR和HR-MS表征.探针3可以定量检测外源性SO2,并且对SO2具有良好的选择性,对其他阴离子和生物硫醇不响应或响应水平低.用350 nm激发,探针3在450 nm处的荧光强度随SO2的浓度增加而增强.当SO2浓度为0~100 μmol·L-1时,荧光强度与其呈良好的线性关系,相关系数R2为0.997.