【作者】 马文辉；

【导师】 彭孝军；

【作者基本信息】 大连理工大学 ， 应用化学， 2011， 博士

【摘要】 检测过渡金属离子和阴离子的水平已引起包括化学家、生物学家、临床生物化学家和环境学家的极大兴趣。荧光分子探针检测法具有便捷、灵敏度高、选择性好、原位检测等优点。香豆素类荧光染料具有优异的光化学光物理性质,诸如良好的光稳定性,高的荧光量子产率和大的Stokes位移等。因此,基于香豆素类染料的荧光分子探针研究备受关注。基于Hg2+诱导脱硫反应,设计合成了香豆素类Hg2+荧光分子探针CHgl-3。在Tris-HCl中性缓冲溶液中,CHgl在常见碱金属离子(K+,Na+)、碱土金属离子(Ca2+, Mg2+)、过渡金属及重金属离子(Cd2+, Ag, Fe3+, Pb2+, Hg2+, Cr3+, Co2+, Ni2+, Cu2+, Zn2+)中能够专一性的识别Hg2+,滴加Hg2+后引起荧光增强12.5倍,光谱红移20nm,溶液荧光由无色变为蓝绿色。CHg2-3对Hg2+的识别效果比CHgl差。CHg2-3分子结构中苯胺环上的供电子基p-OMe和吸电子基p-NO2改变了整个分子的电子密度和ICT效应,从而影响脱硫反应及其对Hg2+的识别。设计合成了连有硼酸基团的香豆素类Cu2+荧光分子探针CCul。在Tris-HCl中性缓冲溶液中,CCul在常见阳离子中能够专一性的识别Cu2+,滴加Cu2+后引起荧光增强5.7倍,光谱蓝移9nm,其它阳离子和常见阴离子(ClO4-, CO32-, SO42-, F-, Cl-,Br-, I-, H2PO4-,AcO-, SCN-)对CCu1检测Cu2+的干扰较小。CCul与Cu2+的络合比为1：2,结合常数为3.996×109M。CCul对Cu2+的识别过程是不可逆的。根据ICT机理设计合成了香豆素类Co2+比率颜色探针CCo1。在Tris-HCl中性缓冲溶液中,CCo1仅对Co2+产生变色响应。滴加Co2+后引起CCol的吸收光谱红移44 nm,溶液颜色由黄绿色变为橙红色。CCol对Co2+产生荧光淬灭响应。CCol与Co2+的络合比为2：1,结合常数为(5.28±0.56)×109M-2。CCo1对Co2+的识别过程是不可逆的。依据CN-的强亲核特性设计合成了两个香豆素类CN-荧光分子探针CCNl-2。在DMF中,滴加CN-后引起CCNl-2的吸收光谱分别蓝移95 nm和89 nm,溶液颜色均由黄绿色变为无色。在考察的阴离子(F-, Cl-, Br-, I-, HSO4-, H2PO4-, AcO-, CN-)中,CCN1-2仅对CN-产生颜色响应并引起荧光淬灭,而且竞争阴离子的存在并不影响它们对CN的检测。更多还原

【Abstract】 Detecting the level of transition metal ions and anions is of great interest to many scientists, including chemists, biologists, clinical biochemists and environmentalists. The advantages of fluorescenct sensors include conveniece, high sensitivity and selectivity, observation in situ, etc. The coumarin dyes have excellent photophysics and photochemistry properties such as high stability against light, high fluorescence quantum yields and big Stokes shift, etc. Therefore, fluorescent sensors based on coumarin have drawn much attention in recent years.The fluorescent sensors CHgl-3 for Hg2+ based on coumarin have been designed and synthesized via Hg2+-induced desulfurization reaction. In Tris-HCl neutral buffer, CHgl exhibits Hg2+-only sensitive among metal ions such as alkali (K+, Na+), alkaline earth (Ca2+, Mg2+), and transition metal ions (Cd2+, Ag+, Fe3+, Pb2+, Cr3+, Co2+, Ni2+, Cu2+, Zn2+). Upon the addition of Hg2+, there are a 12.5-fold intensity enhancement in fluorescence, a 20 nm red-shift in emission maximum and an obvious fluorescence change from almost colorless to bluish green. CHg2-3 have poorer recognition effects for Hg2+ than CHg1.p-OMe (electron-donating group) and p-NO2(electron-withdrawing group) on the aniline ring in CHg2-3 vary the electron cloud density around the molecular and ICT, which have interference on desulfuration reaction and the recognition effects.A boronic acid-linked fluorescent sensor CCul for Cu2+ based on coumarin has been designed and synthesized. In Tris-HCl neutral buffer, CCul exhibits Cu2+-only sensitive among metal ions. Upon the addition of Cu2+, there are a 5.7-fold intensity enhancement in fluorescence and a 9 nm blue-shift in emission maximum. Other metal ions and anions (C1O4-, CO32-, SO42-, F-, Cl-, Br-, I-, H2PO4-, AcO-, SCN-) have no obvious interference for CCul to detect Cu2+. The binding stoichiometry is 1:2 between CCul and Cu2+, and corresponding binding constant is 3.996×109 M-2. The coordination of CCul with Cu2+ is an irreversible process.A ratiometric and colorimetric sensor CCol based on intramolecular charge transfer (ICT) has been designed and synthesized. In Tris-HCl neutral buffer, CCol exhibits Co2+-only color response among metal ions. Upon the addition of Co2+, there are a 44 nm red-shift in absorption maximum and an obvious color change from yellow-green to orange-red. CCol displays fluorescence quenching response toward Co+. The binding stoichiometry is 2:1 between CCo1 and Co2+, and corresponding binding constant is (5.28±0.56)×l09 M-2. The coordination of CCol with Co2+ is an irreversible process.The fluorescent sensors CCNl-2 for CN- based on nucleophilic additional reaction have been designed and synthesized. In DMF, Upon the addition of CN-, there are a 95 nm red-shift for CCN1 and 89 nm for CCN2 in absorption maximum and an obvious color change from yellow-green to colorless. CCNl-2 display CN--only color change and fluorescence quenching response among the anions such as F-, Cl-, Br-, I-, HSO4-, H2PO4-, AcO-, CN-. Other anions have no interference for CCNl-2 to detect CN-.更多还原