Rhodamine 6G-based Chemosensor for the Visual Detection of Cu2＋ and Fluorescent Detection of Hg2＋ in Water

A novel water soluble chemosensor 1 based on rhodamine 6G spirolactam scaffold has been synthesized and characterized.Upon addition of a wide range of the environmentally and biologically relevant metal ions,chemosensor 1 shows a colorimetric selective Cu2＋ recognition from colorless to pink confirmed by UV-Vis absorption spectral changes,while it also exhibits a fluorometric selective Hg2＋ recognition by fluorescence spectrometry.An absorption enhancement factor over 17-fold with 1-Cu2＋ complex and a fluorescent enhancement factor over 45-fold with 1-Hg2＋ complex were observed.Their recognition mechanisms were assumed to be a 1：1 stoichiometry for 1-Cu2＋ complex and a 1：2 stoichiometry for 1-Hg2＋ complex,respectively,which were proposed to be different ligation leading to the ring-opening of rhodarnine 6G spirolactam.Furthermore,the detection limits for CU2＋ or Hg2＋ were 3.3 × 10-8 or 1.7x 10-7 mol/L,respectively.     

Coumarin Modified Rhodamine Derivative： Fluorescent Chemosensor Selectively Recognizing Al^3＋ and Ca^2＋

A fluorescent probe with a coumarin moiety bound to rhodamine 6G hydrazide（l） was synthesized. Its sensing behavior toward various metal ions was investigated with fluorescence methods. Compound I displays different fluorescence emission responses to Al^3＋ and Ca^2＋ at the same excitation wavelength in the visible light region, while no changes occur after the addition of other metal ions. The binding ratios of the complexs of 1-Al^3＋ and 1-Ca^2＋ are both 2：1 according to the Job plot and high resolution mass spectrometer（HRMS） experiments. Moreover, emission spectrum of 1-Ca^2＋ complex and absorption spectrum of the rbodamine dyes overlap largely. When Al^3＋ was added to the 1-Ca2＋ system, calcium in complex 1-Ca2＋ can be displaced by Al^3＋, resulting in the output of another ratiometric sensing signal, which demonstrates that the 1-Ca^2＋ complex can be served as a new and effective fluorescence resonance energy transfer（FRET） donor for rhodamine derivatives.     

A Novel Coumarin-based Fluorescence Chemosensor for Fe^3＋

A novel coumarin derivative[7-diethylamino-2-oxo-2H-chromene-3-carboxylic acid（6-amino-pyridin2-yl）-amide,CFe1] has been synthesized and its potential application as a chemosensor for the detection of metal ions has been further investigated.The responses of CFe1 to Fe^3＋ were studied by fluorescence emission spectrometry in the presence of other metal ions such as Al^3＋,Ba^2＋,Ca^2＋,Co^3＋,Cr^3＋,Cu^2＋,Fe^2＋,Hg^2＋,Mg^2＋,Mn^2＋,Na^＋,Ni^＋,Pb^2＋,Zn^2＋,K^＋,and Ag^＋.CFe1 showed a good selectivity for Fe^3＋ with fast response,a wide pH span of 3.3-9.18,and a large Stocks shift.CFe1 in the presence of Fe^3＋ and ethylene diamine tetraacetic acid（EDTA） makes the blue solution fade to colorless,which is due to the formation of CFe1-Fe^3＋ complex instead of any catalytic action of Fe^3＋.Furthermore,the imaging of Fe^3＋ in cultured single mice microglia cells was realized with the aid of CFe1,indicating that CFe1 has a great potential to be used as promising models for the future design of novel and robust chemosensor for metal ion detection in the field of biomedical and environmental analyses.     

Cu2＋和Fe3＋与明胶的相互作用

利用荧光猝灭法, 研究了不同温度、酸度下, Cu2＋和Fe3＋与明胶的相互作用.计算了猝灭常数和结合常数.紫外光谱和显微红外光谱的测定结果表明, Cu2＋、Fe3＋与明胶分子中的酰胺键发生了作用.探讨了猝灭机理.计算出的热力学函数表明,在Cu2＋、Fe3＋与明胶的相互作用过程中熵变起主要的作用.     

新型荧光碳点的制备及其在Hg2+检测中的应用

以中药材川佛手为碳源,通过高温热解产生的烟制备了平均粒径为6 nm的新型荧光碳点,其最大激发波长285 nm,最大荧光发射波长340 nm。 基于碳点良好的荧光性能及Hg²⁺对碳点荧光的猝灭作用,建立了检测Hg²⁺的新方法。 结果表明,在0.2 mol/L磷酸盐缓冲溶液(pH=7.0)中,响应时间为2 min时,该方法具有良好的选择性和抗干扰能力,检测Hg²⁺浓度的线性范围为0.2~40 μmol/L,相关系数为r=0.9996,检出限为0.052 μmol/L。 当加入2.0和40.0 μmol/L Hg²⁺到实际水样后,相对标准偏差(RSD)和加标回收率分别为0.3%~2.4%和99.5%~101.1%,可用于实际水样中Hg²⁺的分析检测。     

没食子酸介导合成的还原型氧化石墨烯对荧光官能团的选择性识别

本文以氧化石墨烯为前体,没食子酸为还原剂和稳定剂,通过简单的水浴加热法一步合成了还原型氧化石墨烯.利用紫外可见吸收光谱、傅里叶红外光谱、拉曼光谱、X-射线衍射及扫描电子显微镜对产物进行了一系列分析表征.结果表明,没食子酸可将氧化石墨烯还原为石墨烯.此外,还考察了制备的还原型氧化石墨烯对阴阳离子荧光官能团荧光强度的影响.结果表明,没食子酸介导合成的还原型氧化石墨烯能有效猝灭罗丹明等阳离子官能团的荧光,而增强荧光素类阴离子官能团的荧光,因此可以选择性地识别荧光官能团.     

A Quinoline Derivated Chemosensor for Cu^2＋ Recognition

A quinoline derivative N-(2-hydroxyl-naphthylmethyl)-N-(quinol-8-yl)amine(2) was synthesized and characterized, which can selectively recognize Cu2+ over other metal ions such as Zn2+, Cd2+, Sn2+, Pb2+, Hg2+, Ni2+, Mg2+, Cr3+, Mn2+, Sr2+, K+, Ca2+, Na+, Ba2+ in acetonitrile/water(volume ratio 99:1). Cu2+ induced a new absorption peak at 464 nm in the absorption spectrum(ε=4.66×102 L·mol-1·cm-1) and quenched the fluorescence emission of quinoline derivative 2. The binding of quinoline derivative 2 to Cu2+ wa...     

吡唑啉衍生物与溶剂相互作用的研究

通过对一类吡唑啉衍生物（1-苯基-3-（N，N-二甲基氨基苯乙烯）-5-（4-N，N-二甲基氨基苯基）-2-吡唑啉）在不同溶剂中的光谱行为，研究了该衍生物和溶剂分子间的一般相互作用和特殊相互作用．发现利用吡唑啉溶液的荧光猝灭现象能对其和溶剂分子间不同相互作用问题提供有价值的信息．     

一种可用于检测苦味酸的水溶性共轭聚合物荧光传感器的制备及应用

制备了一种高灵敏的水溶性荧光共轭聚合物(PPE-OBS), 将其用于苦味酸的荧光检测. 利用质谱、 核磁共振波谱和红外光谱等方法对PPE-OBS进行了表征, 并对其检测苦味酸的条件进行了优化. 结果表明, 在硼酸-氢氧化钠缓冲溶液(pH=9.5)中作用20 min, 苦味酸对PPE-OBS荧光的猝灭效率最大. 在最优条件下, PPE-OBS检测苦味酸的线性范围为1.0~60 μmol/L(R²=0.999), 检出限为0.831 μmol/L(S/N=3). 将PPE-OBS制成荧光试纸用于检测环境样品中的苦味酸, 获得了较好的检测结果.     

Cu~(2 )和 Fe~(3 )与明胶的相互作用

利用荧光猝灭法,研究了不同温度、酸度下,Ｃｕ２＋和 Ｆｅ３＋与明胶的相互作用．计算了猝灭常数和结合常数．紫外光谱和显微红外光谱的测定结果表明,Ｃｕ２＋、Ｆｅ３＋与明胶分子中的酰胺键发生了作用．探讨了猝灭机理．计算出的热力学函数表明,在Ｃｕ２＋、Ｆｅ３＋与明胶的相互作用过程中熵变起主要的作用．     

基于罗丹明类衍生物荧光增强的水体中Hg^2＋检测

利用一种罗丹明衍生物荧光探针的开环效应检测Hg2＋.在pH 7.0的Tris-HCl缓冲液中,Hg2＋与荧光探针结合导致罗丹明类衍生物开环,溶液颜色由无色变成粉红色,并且发射强的荧光.荧光强度与Hg2＋浓度在20~200 ng/L范围内呈良好的线性关系,检出限为4 ng/mL.实验考察了荧光探针的选择性以及温度、pH、荧光试剂浓度和盐度对Hg2＋检测的影响.结果表明该方法具有反应试剂水溶性好、选择性好和可常温检测等优点.方法应用于自来水、河水和湖水等水体中Hg2＋的检测,获得较好的回收率.     

手性双修饰剂修饰的CdSe纳米晶的合成及选择性识别Hg(II)的研究

以手性化合物D-青霉胺和L-半胱氨酸为双修饰剂在水相中合成了CdSe纳米晶, 痕量Hg(II)对其荧光强度有明显猝灭作用,基于此建立了定量测定痕量Hg(II)的新方法.在Cd2+, HSe-, D-Pen和L-Cys摩尔比为1: 0.25: 2: 1.2, pH=7.5的条件下,合成的纳米晶具有更好的发光强度和稳定性.TEM显示CdSe纳米晶为球形颗粒,粒径约为50和80 nm.在磷酸盐缓冲溶液(pH 7.38)中,CdSe纳米晶最大荧光峰为516 nm,对Hg(II)有高选择性响应.纳米晶的相对荧光强度与Hg(II)的浓度呈良好线性关系, 检出限为40 pmol/L.本方法测定不同水样中Hg(II)的浓度,回收率为96.7%～102.5%.     

Naphthalimide as Highly Selective Fluorescent Sensor for Ag^＋ Ions

The naphthalimide derivative. NA1 was synthesized, which consists of a bis（2-（ethylthio）ethyl）amine group binding cations and naphthalimide unit as chromogenic and fluorogenic signaling subunit. Absorption and emission spectra and the effect of polarity of solvents and pH values were studied. The photo-induced electron transfer （PET） occurred from the donor of bis（2-（ethylthio）ethyl）amine group to the naphthalimide fluorophore. The present study demonstrates that NA1 is a viable candidate as a fluorescent receptor for a new Ag^＋ ion sensor. This silver ion chemosensor can discriminate Ag^＋ ion well among heavy metal ions by an enhancement of the fluorescence intensity in ethanol-water （1 ： 9, V ： V）. And NA1 is also a pH-sensor because the fluorescence of the compound varies with the pH values.     

2-氨基-5-(对二甲氨基)苯基-1,3,4-噻二唑:Hg2+的选择性荧光传感分子

设计合成了结构简单的分子内电荷转移荧光传感分子1,3,4-噻二唑类衍生物(1), 实现了水-乙醇(体积比1∶9)混合溶剂中Hg2+的荧光猝灭型选择性灵敏传感, 荧光猝灭常数达5.5×105 mol-1·L, Hg2+线性响应范围为5.0×10-6～5.0×10-5mol/L. 基于等摩尔连续变化法、红外光谱和核磁滴定实验结果提出了传感分子1与Hg2+的1∶1型结合模式, 其中1-位S原子和2-位胺N原子为Hg2+配位原子; 结合光谱变化讨论了Hg2+结合显著增强分子内电荷转移的荧光猝灭机理.     

阳离子表面活性剂与曙红Y的荧光反应及其分析应用

研究阳离子表面活性剂(CSAA)在水溶液中与曙红Y的荧光反应, 发现当CSAA单体与曙红Y形成离子缔合物时, 荧光发生猝灭, 而CSAA胶束与曙红Y作用又会出现一个新的、更强的荧光。荧光猝灭反应具有很高的灵敏度, 对于不同的CSAA, 其检测限在6.6-12.0ng/mL之间, 可用于痕量CSAA的测定。此外, 荧光猝灭和新荧光的产生也为研究表面活性剂和荧光染料在溶液中的存在状态提供了新的途径。还研究了反应体系的荧光特征、适宜条件并讨论了反应机理。     

PNTU探针-荧光猝灭法测定Hg2+的含量

制备了一种硫脲分子PNTU探针,基于其对Hg~(2+)的专一性比色识别,建立了荧光猝灭法测定Hg~(2+)含量的方法。在4-溴-1,8-萘酐的乙醇溶液中,逐滴加入2 mL 80%(质量分数)水合肼溶液,反应完成后,经抽滤,乙醇、水洗涤后干燥,再加入10 mL吡咯烷,在氮气保护下继续反应,得到红褐色固体。将其溶于15 mL乙腈中,室温搅拌下滴加1 mL异硫氰酸苯酯,反应完成后,经减压浓缩、水洗得到PNTU探针。将PNTU探针溶液与体积比为8∶2的乙腈-4-羟乙基哌嗪乙磺酸缓冲液的混合液混匀,然后加入含Hg~(2+)的样品溶液,采用荧光猝灭法测定体系的荧光强度。结果显示:当加入Hg~(2+)时,体系的荧光强度明显降低,溶液颜色由黄色变成橙红色;干扰试验表明PNTU探针在有其他金属离子存在的情况下仍可检测出Hg~(2+);Hg~(2+)浓度在20.0μmol·L~(-1)以内与其对应体系的荧光强度降低值呈线性关系,检出限(3S/N)为1.8 nmol·L~(-1);对实际水样进行3个浓度水平的加标回收试验,Hg~(2+)的回收率为99.6%～104%,测定值的相对标准偏差(n=5)为0.85%～2.6%。基于PNTU探针制备了Hg~(2+)的检测试纸,可方便快捷地检测样品中是否存在Hg~(2+)。     

一种新型罗丹明类Hg2+荧光探针的合成与分析应用

设计合成了一种可逆的Hg2+荧光增强型分子探针3’,6’-双(二乙氨基)-2-((2-羟基-4-甲氧基苯亚甲基)氨基)螺[异吲哚-1,9’-氧杂蒽]-3-硫酮(RBS),并利用红外光谱、元素分析、核磁等方法对探针结构进行表征。探针本身荧光很弱,与Hg2+结合后荧光显著增强,由此,建立了Hg2+测定的新方法。该方法对Hg2+测定的线性范围为5.00×10-9～1.10×10-6mol/L,检出限为2.82×10-9mol/L,具有操作简单、灵敏度高、选择性好、线性范围宽等特点。将该方法用于河水及土壤样品中Hg2+的加标回收实验,结果满意。     

多元线性模型计算基于荧光猝灭原理的膜传感器对分析物的响应参数

根据基于荧光猝灭原理的化学传感膜的结构特征和发光机理,推导并提出量化作用于膜传感器的多种荧光猝灭因素的多元线性模型.结合三杯法,该模型可简便地求出反映不同荧光猝灭机理的特征参数.通过建立的数学模型,测定并计算了芘丁酸膜传感器对应于呋喃妥因等23种药物多种荧光猝灭因素的响应数据和响应参数.结果表明,传感膜对分析物的响应特征往往能得到主要猝灭因素响应模型的近似反映,这为基于荧光猝灭原理的化学传感器定量分析模型的建立提供了可借鉴的思路和方法.     

Novel Chromogenic Chemosensors for Fluoride Anion Based on 8-Hydroxyquinoline Azo Derivatives

A series of 8-hydroxyquinoline azo derivatives with diverse conjugated structures were synthesized and studied to chromogenicaUy detect anions. All the dyes allowed selective detection for fluoride anion in CH3CN via instant deprotonation of the compounds, which was affirmed by UV-Vis absorption and 1H NMR spectra. The chromogenically responding ability increases as the substituent changes from phenyl to naphthyl or anthryl. This result is likely to be related to the enhancement of intramolecular charge transfer （ICT） induced by extension of conjugated structure.     

1—4,二（萘[2,1—d]并恶唑—2‘）苯为敏感试剂的荧光光纤传 …

将１，４－二（萘「２，１－ｄ」并恶唑－２‘）苯包埋在增塑的聚氯乙烯膜中，基于甲硝唑对ＢＮＯＢ的可逆猝灭，研制了一种甲硝唑荧光光纤传感器，传感器可逆性好，响应时间小于４０ｓ，响应线性范围为８．０×１０＾－６－１．０×１０＾－３ｍｏｌ．Ｌ＾－１，检出限为４．０×１０＾－６ｍｏｌ．Ｌ＾－１，常见的无机离子，药物不干扰甲硝唑的测定，传感器用于药品制剂中甲硝唑的测定，结果与药典法一致。