基于有机硅化合物的反应型氟离子荧光化学传感器

作为半径最小的阴离子,氟离子(F-)表现出高电负性和强碱性,因而具有特殊的化学性质。由于F-与人类健康和环境安全密切相关,因此它的识别与检测已引起了人们极大的关注。到目前为止,用于选择性检测F-的荧光化学传感器已有大量报道,这些传感器主要是基于有机硼化合物和氢键质子给体。与这些传感器相比,反应型传感器具有更高的选择性,并且更容易在水环境中实现F-检测。本文根据有机硅化合物的结构不同,分别综述了近年来基于硅醚、硅炔及其他有机硅化合物的反应型氟离子荧光化学传感器的合成研究进展,其中包括本课题组的一些研究工作。     

基于BODIPY衍生物的氟离子荧光比例探针的研究

利用有机合成中Si-O键受氟离子（F-）作用断裂形成O-的机理,开展了以荧光染料BODIPY-PhOSi作为荧光探针检测溶液中的微量氟离子的研究。BODIPY-PhOSi受氟离子作用形成BODIPY-PhO-,引起荧光强度变化,从而达到检测微量氟离子的作用。实验通过有机反应合成了荧光探针BODIPY-PhOSi,然后采用荧光光谱仪进行低浓度溶液中微量氟离子滴定实验,得到不同浓度氟离子的荧光光谱曲线,谱图分析表明荧光探针BODIPY-PhOSi对氟离子的响应呈比例比色型,通过数据计算得到荧光探针的最小检测限,在对比实验中氟离子检测表现出了良好的选择性。     

用基于苯并噻二唑衍生物的比率荧光化学传感器检测氟离子

研制了一种用于灵敏、快速地检测溶液中的氟离子的基于苯并噻二唑衍生物的荧光传感器.4,7-二溴-2,1,3-苯并噻二唑与三甲基硅基乙炔通过Sonogashira偶联反应得到二取代的三甲基硅基乙炔苯并噻二唑;将该化合物用于检测氟离子,分析了检测灵敏度和选择性.结果表明,在乙腈和水(V/V=9∶1)混合溶液中,合成的苯并噻二唑衍生物的最大发射波长峰值为455nm(激发波长为376nm);就所测试的F-,Cl-,Br-,I-,ClO4-,AcO-,NO3-,H2PO3-,CN-和HSO4-等阴离子而言,仅F-可以脱除三甲基硅保护基使得该化合物荧光最大发射波长蓝移至435nm,荧光强度降低60%,且最低检测限可达4.5×10-8 mol/L.因此,二取代的三甲基硅基乙炔苯并噻二唑应用于氟离子检测具有很好的灵敏度和选择性.     

席夫碱类高选择性氟离子化学传感器的研究

以邻羟基萘甲醛和水合肼合成了席夫碱类化合物荧光黄101(DHNA),在F-存在的情况下,其紫外可见光谱和荧光光谱都发生明显的变化,同时溶液颜色和荧光的变化可以通过肉眼直接观测到.在Cl-、Br-、1-、HSO4-、H2PO4-;等干扰离子存在的情况下,DHNA对F-具有良好的选择性.因此,荧光黄101可用于制备检测F-的高灵敏度颜色.荧光传感器.     

快速响应氟离子反应型荧光探针的设计合成与光谱学研究

本文基于萘环和吩噻嗪环的荧光特性,设计合成了4个氟离子反应型荧光探针。通过研究其光物理性质发现,吩噻嗪环为荧光团的氟离子探针响应时间比萘环的短,在2 min内能快速响应氟离子。探针PSC响应氟离子后,不仅提高了探针灵敏度,还对常见的阴离子、阳离子和其他小分子等具有较强的抗干扰性。     

多肽荧光传感器检测铜离子

基于铜离子对罗丹明B标记的多肽的荧光猝灭作用,构建了一种用于铜离子检测的荧光传感器.利用共振光散射分析、紫外-可见吸收光谱、荧光寿命测试和圆二色光谱研究了铜离子检测的传感机理,发现铜离子的加入诱导多肽结构发生变化而使罗丹明B荧光团彼此靠近,从而导致铜离子与多肽之间发生聚集诱导荧光猝灭.实验结果表明,该传感器检测铜离子的线性范围为5×10^-4～1×10^-2μmol/L和0.1～7μmol/L,检出限为0.29 nmol/L,且拥有良好的选择性,能用于湖水样品中铜离子的检测.     

基于二苯基咪唑的氟离子荧光探针的合成及性能

本文设计制备了一种二苯基咪唑衍生化的荧光探针1,利用紫外-可见吸收光谱和荧光光谱研究探针对阴离子的选择性。在探针的乙腈溶液中引入F_^-后,606 nm处的荧光强度发生明显的猝灭,并且可通过裸眼识别F_^-。探针对F_^-的识别表现出高灵敏性以及较好的抗干扰能力,检测限可低至9.43×10_^-8 mol L_^-1。此外,制备的1+F_^-体系对湿度较敏感,在水分影响下该体系的颜色和荧光强度能够实现可逆恢复。     

氟硼二吡咯亚甲基类荧光探针在离子检测中的应用进展

氟硼二吡咯亚甲基类(BODIPY)类化合物具有摩尔吸光系数高、荧光量子产率高、吸收波长在可见光或近红外区域、荧光寿命长和光稳定性好等特点,并且其荧光对溶剂的极性和pH均不敏感,是一类可应用于生物领域的荧光染料,近年来,此类化合物被广泛用于设计合成荧光传感器分子,用于各种离子的检测,此类荧光探针具有分析灵敏度高、选择性好等特点.综述了氟硼二吡咯亚甲基类荧光探针在离子识别和检测中的应用,并展望了该领域的前景.     

配位型钯离子荧光探针的研究进展

钯在珠宝行业、工业催化、制药行业中应用广泛,也是汽车尾气排放装置触媒转换器中最重要的催化剂之一,但残留的钯离子对人体健康和环境有着极大的危害。近几年,人们对于钯离子残留的检测越来越重视,而配位型金属离子荧光探针是最方便且能快速检测离子的一种方法。本文根据配位方式的不同,综述了配位型钯离子荧光探针的研究进展,包括氮族元素配位(如N和P)的荧光探针、氧族元素配位(如O、S和Se)的荧光探针、同时与氮族和氧族元素配位的荧光探针、不饱和键配位的荧光探针以及聚合物荧光探针等。对不同配位方式、探针结构及对钯的检测效果进行了分析,希望能够为设计更灵敏、高效的配位型钯离子荧光探针提供启发。     

喹啉衍生物锌离子荧光传感器*

本文综述了近年来用于锌离子检测的喹啉衍生物荧光传感器的研究进展,介绍了基于喹啉、8-羟基喹啉和8-氨基喹啉合成的锌离子荧光传感器的结构和设计原理,概述了锌离子对喹啉衍生物荧光传感器光学性能的影响,分析了喹啉衍生物锌离子荧光传感器在检测过程中的优点及其实际应用价值,并展望了这类锌离子荧光传感器的研究和发展方向。     

A PEGylated Fluorescent Turn‐On Sensor for Detecting Fluoride Ions in Totally Aqueous Media and Its Imaging in Live Cells

Owing to the considerable significance of fluoride anions for health and environmental issues, it is of great importance to develop methods that can rapidly, sensitively and selectively detect the fluoride anion in aqueous media and biological samples. Herein, we demonstrate a robust fluorescent turn‐on sensor for detecting the fluoride ion in a totally aqueous solution. In this study, a biocompatible hydrophilic polymer poly(ethylene glycol) (PEG) is incorporated into the sensing system to ensure water solubility and to enhance biocompatibility. tert‐Butyldiphenylsilyl (TBDPS) groups were then covalently introduced onto the fluorescein moiety, which effectively quenched the fluorescence of the sensor. Upon addition of fluoride ion, the selective fluoride‐mediated cleavage of the Si? O bond leads to the recovery of the fluorescein moiety, resulting in a dramatic increase in fluorescence intensity under visible light excitation. The sensor is responsive and highly selective for the fluoride anion over other common anions; it also exhibits a very low detection limit of 19 ppb. In addition, this sensor is operative in some real samples such as running water, urine, and serum and can accurately detect fluoride ions in these samples. The cytotoxicity of the sensor was determined to be Grade I toxicity according to United States Pharmacopoeia and ISO 10993‐5, suggesting the very low cytotoxicity of the sensor. Moreover, it was found that the senor could be readily internalized by both HeLa and L929 cells and the sensor could be utilized to track fluoride level changes inside the cells.     

Leveraging Material Properties in Fluorescence Anion Sensor Arrays: A General Approach

As the demand for probes suitable for sensor development increases, investigation of approaches that utilize known successful receptors gains in general importance. This study describes a two‐prong approach that can be used as a guide to developing sensors from known receptors. First, the conversion of a simple receptor, calix[4]pyrrole, into a fluorescent probe to establish a ratiometric signal is described. Secondly, the sensors that employ an output from a single ratiometric calix[4]pyrrole probe are fabricated by using poly(ether‐urethane) hydrogel copolymers. These hydrogels are designed to absorb, internalize and transport aqueous electrolytes. A sensor array of ten different poly(ether‐urethane) matrices with varying comonomer proportions were doped with a single probe and were exposed to eight different anions: acetate, benzoate, fluoride, chloride, phosphate, pyrophosphate, hydrogen sulfide, and cyanide, eight urine samples and anti‐inflammatory drugs (NSAIDs). The poly(ether‐urethane) matrices comprise different proportions of anion‐binding urethane moieties and different hydrophilicity given by the ratio between ethylene glycol ether and butylene glycol ether. This diversity in the hydration behavior provides different environment polarity, in which the recognition and self‐assembly processes display enough diverse behavior to allow for unique response of the probe to the analytes. Furthermore, a single probe is shown to recognize eight different aqueous anions and eight urine samples when embedded in ten different polyurethanes in an array that displays 100 % classification accuracy. To demonstrate the potential of the concept for quantitative studies, an estimation of non‐steroidal anti‐inflammatory drugs ibuprofen and diclofenac in water and in saliva was performed. A limit of detection of 0.1 ppm and a dynamic range of 0.1–0.6 and 0.05–60 ppm was observed, respectively. Given the general difficulty of chemosensors to recognize aqueous anions, the fact that one probe recognizes eight different analytes attests to an enormous effect of the polymer environment on the recognition process. This method could be used to generate a variety of sensor arrays for various analyses including species that are difficult to recognize, such as small‐molecule‐ and inorganic anions.     

A Pyrene‐functionalized Polynorbornene for Ratiometric Fluorescence Sensing of Pyrophosphate

A novel pyrene‐functionalized polynorbornene ( P1 ) bearing sulfonamide NH and triazolium donors has been synthesized for ratiometric fluorescence sensing of PPi in aqueous solution. In addition, P1 is also used to monitor intracellular PPi and to detect PPi released during polymerase chain reaction.     

Development of a Fluorescent Pb2+ Sensor

A real turn‐on : The emission intensity of heterocycle 1 increases upon binding to Pb²⁺. Thus, 1 acts as a small‐molecule “turn‐on” fluorescent sensor for lead. The sensor is highly selective and is functional over a wide range of pH values.

     

An Ultrafast Molecular-Rotor-Based Fluorescent Turn-On Sensor for the Perrhenate Anion in Aqueous Solution

Devising sensors for the perrhenate anion in aqueous media is extremely challenging, and has seldom been reported in the literature. Herein, we report a fluorescence turn-on sensor for the perrhenate anion in aqueous media based on the aggregation-induced emission of a popular ultrafast molecular rotor dye, Thioflavin-T. The selective response towards the perrhenate anion has been rationalized in terms of matching water affinity, with the weakly hydrated perrhenate anion spontaneously forming a contact ion pair with the weakly hydrated ultrafast molecule-rotor-based organic cation, Thioflavin-T, which in turn leads to an aggregate assembly that provides a fluorescence turn-on response towards perrhenate. The sensing response of Thioflavin-T has been found to be quite selective towards the perrhenate anion when tested against anions that are ubiquitously present in the environment, such as chloride, nitrate, and sulfate anions. The formation of self-assembled Thioflavin-T aggregates has also been investigated by time-resolved emission and temperature-dependent measurements.     

Iron(III)‐Selective Chelation‐Enhanced Fluorescence Sensing for In Vivo Imaging Applications

A “turn‐on” pattern Fe³⁺‐selective fluorescent sensor was synthesized and characterized that showed high fluorescence discrimination of Fe³⁺ over Fe²⁺ and other tested ions. With a 62‐fold fluorescence enhancement towards Fe³⁺, the probe was employed to detect Fe³⁺ in vivo in HeLa cells and Caenorhabditis elegans, and it was also successfully used to elucidate Fe³⁺ enrichment and exchange infected by innexin3 (Inx3) in hemichannel‐closed Sf9 cells.