高选择性锌离子荧光探针的合成与性质研究

通过便宜易得的水杨醛和硫酸肼为原料一步反应得到吖嗪类化合物L。该化合物本身在乙腈溶液中无荧光,不过,当向其中加入Zn2+后,产生强的荧光,而其他金属离子都无荧光增强现象,而且该化合物加入Zn2+后发射波长从545蓝移到509 nm,化合物L是一种高选择性的Zn2+荧光探针。     

一种Zn~(2+)离子荧光探针的合成及其荧光性质

以2,3-二氨基甲苯为原料经过氨基保护、溴代、水解等反应制备2,3-二氨基苯甲醇,后者与芳香醛缩合成苯并咪唑,再经MnO2氧化、缩合生成2-(4-(4-(羟甲基)-1H-苯并[d]咪唑-2-基)-1H-苯并[d]咪唑-2-基)苯酚。经1 H-NMR对中间体和目标产物进行结构表征,并研究了产物的紫外、荧光性质,结果表明目标化合物能选择与Zn2+进行配位,产生较强的荧光,荧光量子收率为0.64,斯托克斯位移为142nm。     

苯并咪唑类荧光探针的合成及离子选择性研究

以2-氨基苯并咪唑和邻羟基萘甲醛为原料合成了苯并咪唑席夫碱类荧光探针,并利用红外光谱和核磁氢谱对其结构进行了表征,通过荧光光谱研究了探针对不同金属离子的识别作用。结果表明:Zn~(2+)离子的加入不仅使探针荧光强度显著增强,而且溶液荧光颜色由弱黄色变为强绿色,说明探针对Zn~(2+)离子具有专一识别能力。同时,干扰实验表明探针对Zn~(2+)离子的识别具有良好的抗干扰能力。     

用于检测氟离子的荧光探针的制备

设计合成了基于萘胺为荧光团的的氟离子荧光探针。通过核磁表征了荧光探针的结构。研究了该探针在加入F-前后吸收光谱和发射光谱的变化。结果表明,随着F-的加入,探针有明显的荧光增强。另外,探针具有良好的选择性,加入其他阴离子不影响其光谱性质。以上性能证明,该探针有望应用于检测F-的荧光传感器。     

一种基于双喹啉结构的荧光探针的合成及其对Cd~(2+)的荧光识别

合成了一种含有双喹啉荧光团的希夫碱型荧光探针DQS并表征了其结构。在CH3CH2OH/H2O(1/1,v/v,HEPES 20 m M,p H=7.4)溶液中,DQS对Cd2+具有快速选择性识别作用,Cd2+可引起DQS在483 nm处的荧光发射发生猝灭,其它金属离子不能引起明显的光谱变化。DQS与Cd2+的结合比为1:1,结合常数为4.3×104 L/mol,DQS对Cd2+的检测限可达6.7×10-6 M。     

色酮-3-甲醛席夫碱新型荧光探针高选择性检测CN离子

以色酮-3-甲醛和3-氨基吡唑为原料,通过一锅法缩合反应得到新型猝灭型席夫碱荧光探针Z.在V(DMSO):V(H2 O)=3:2的溶液中,通过选择性、灵敏度、抗干扰、稳定性及pH影响等实验,证实该探针具有较好的稳定性,能够高灵敏度和选择性地识别CN-,最低检测限为1.9×10-8 mol/L.进一步荧光滴定实验和机理研...     

铽离子荧光探针对钙调素的研究与进展

Tb3 离子能够取代钙调素中的钙离子而影响其生物功能,因此可作为荧光探针对钙调素进行研究.概述了Tb3 离子荧光探针对钙调素的研究进展情况.     

一种新型罗丹明类双通道荧光探针及其对Fe~(3+)和Cu~(2+)的选择性识别研究

以罗丹明B、水合肼和吡啶-2-甲醛为反应物,合成了一种新型的罗丹明类Fe~(3+)和Cu~(2+)双通道分子探针(Fluorescent probe,FP),并用核磁和质谱对其分子结构进行了表征。利用荧光分光光度计和紫外可见分光光度计研究了FP对Fe~(3+)、Cu~(2+)等14种金属离子的识别性能。研究结果表明,在V(CH_3OH)∶V(H_2O)=1∶1体系中,当选用荧光光谱分析时,探针FP对Fe~(3+)具有良好的选择性响应,且Fe~(3+)浓度在2~30μmol/L时,探针荧光强度与Fe~(3+)浓度呈线性关系,线性相关系数为0.998。当选用紫外可见光谱分析时,探针FP对Cu~(2+)具有很好的选择性响应,且当Cu~(2+)浓度为0~9μmol/L时,探针FP的吸光度与Cu~(2+)浓度呈线性关系,线性相关系数为0.999。     

RAFT方法合成的共聚物荧光探针及其氟离子检测性能

本文基于分子间质子转移和诱导分子内电荷转移(ICT)机理,合成了以萘酰亚胺为发光基团、苯甲酰为F-检测基团的荧光单体,并采用可逆加成-断裂链转移(RAFT)聚合方法将其与N-异丙基甲基丙烯酰胺(NIPAM)进行共聚,制备了一种可以用于F-检测的共聚物荧光探针poly(NIPAMm-co-Napn)(简称PNap334),并分别在二氯甲烷-二甲基亚砜(9/1,V/V)溶液和固体薄膜中考察了聚合物PNap334对F-的响应。研究发现,聚合物溶液和聚合物膜对F-均有很好的识别作用,聚合物溶液对F-的检测限为1.05μmol/L。     

稀土离子(Gd~(3+),Ce~(3+)/Ce~(4+),Eu~(3+))对Tb~(3+)掺杂硅酸盐玻璃发光性能的影响

研究了(Gd3+,Ce3+/Ce4+,Eu3+)对Tb3+掺杂硅酸盐玻璃发光性能的影响.结果表明:Tb3+掺杂硅酸盐玻璃可以发出弱蓝光(400～460 mm)和较强的绿光(480～600mm).Gd3+对Tb3+的发光起敏化作用,可提高TB3+掺杂硅酸盐玻璃的发光强度.在空气中熔制的玻璃中Ce3+和Ce4+同时存在,Ce3+对Tb3+发光起敏化作用;而Ce4+对Tb3+发光起淬灭作用.由于Ce4+比例比较高,CeO2加入导致TB3+发光强度降低,同时也缩短了Tb3+发光余辉.加入Eu2O3时,Eu3+自身发光分散了激发Tb3+发光的能量,使Tb3+的特征发射强度降低.     

聚丙烯酸功能化LaF_3:Ce~(3+)/Tb~(3+)荧光探针测定鲑鱼精DNA

用溶剂热法,160℃条件下,反应12 h,成功制备了La F3:Ce3+/Tb3+晶体(PDF 72-1435)。用XRD对材料进行了表征。并用聚丙烯酸(PAA)对材料进行了功能化,红外吸收光谱显示材料表面成功修饰上羧基(─COOH)。以COOH-La F3:Ce3+/Tb3+材料为荧光探针,基于DNA对材料的发光淬灭,实现了对DNA的定量测定。在p H=5.5条件下,功能化荧光材料的荧光强度和鲑鱼精DNA(hs-DNA)的浓度(0.60²5.0μg/m L)呈线性关系,线性方程为ΔF=113.9-1.5c,检测限为0.97μg/m L,相关系数R=0.998 2,RSD为0.97%。     

Preparation and Characterization of Imprinted Porous Materials with High Selectivity for Luteolin

In order to selectively separate luteolin from its crude solution, we synthesized imprinted porous materials with high recognition specificity for luteolin, using an imprinting technique. Modified luteolin was used as template, vinyltriethoxysilane as the functional monomer, and tetraethyl orthosilicate (TEOS) as the cross‐linking agent. The results showed the following optimum reaction conditions: The reaction ratio between luteolin and acryloyl chloride was 1 : 2 (0.10 g/0.20 g), adding 1.0 g precursor; the feasible elution time was 12 h; when the molar quantity of modified template molecule was 0.01 mol and ethenyltriethyloxy‐silane (VTEO) was 0.04 mol, the maximum yield reached 91.6 %. All samples were tested by Brunauer‐Emmett‐Teller method, Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy, equilibrium adsorption experiments and selective adsorption experiments. It was found that the imprinted porous materials showed excellent selectivity for luteolin in aqueous solution. Characterization by FTIR suggested that an addition reaction had occurred between the modified template molecule and VTEO while forming ester bonds in the functional precursor. Results from pore structure analysis indicated that the imprinted porous materials had good channels, and the average pore size of the prepared porous materials was between 35.85 and 95.82 Å. Adsorption dynamics analysis suggested that, when the adsorption time reached 3 h, the adsorption process had reached balance and the adsorption capacity was at steady state. These porous materials had highly selective recognition properties and high equilibrium adsorption capacity for the template molecule. The equilibrium adsorption capacity of the imprinted porous materials to the template molecule was 11.4 times that of the blank porous materials.     

Development of Polyamine-Substituted Triphenylamine Ligands with High Affinity and Selectivity for G-Quadruplex DNA

Currently, significant efforts are devoted to designing small molecules able to bind selectively to guanine quadruplexes (G4s). These noncanonical DNA structures are implicated in various important biological processes and have been identified as potential targets for drug development. Previously, a series of triphenylamine (TPA)-based compounds, including macrocyclic polyamines, that displayed high affinity towards G4 DNA were reported. Following this initial work, herein a series of second-generation compounds, in which the central TPA has been functionalised with flexible and adaptive linear polyamines, are presented with the aim of maximising the selectivity towards G4 DNA. The acid–base properties of the new derivatives have been studied by means of potentiometric titrations, UV/Vis and fluorescence emission spectroscopy. The interaction with G4s and duplex DNA has been explored by using FRET melting assays, fluorescence spectroscopy and circular dichroism. Compared with previous TPA derivatives with macrocyclic substituents, the new ligands reported herein retain the G4 affinity, but display two orders of magnitude higher selectivity for G4 versus duplex DNA; this is most likely due to the ability of the linear substituents to embrace the G4 structure.     

Understanding the Selectivity Mechanism of the Human Asialoglycoprotein Receptor (ASGP-R) toward Gal- and Man-type Ligands for Predicting Interactions with Exogenous Sugars

A practical approach for addressing the computer simulation of protein-carbohydrate interactions is described here. An articulated computational protocol was set up and validated by checking its ability to predict experimental data, available in the literature, and concerning the selectivity shown by the Carbohydrate Recognition Domain (CRD) of the human asialoglycoprotein receptor (ASGP-R) toward Gal-type ligands. Some required features responsible for the interactions were identified. Subsequently the same protocol was applied to monomer sugar molecules that constitute the building blocks for alginates and ulvans. Such sugar polymers may supply a low-cost source of rare sugars with a potential impact on several industrial applications, from pharmaceutical to fine chemical industry. An example of their applicative exploitation could be given by their use in developing biomaterial with adhesion properties toward hepatocytes, through interaction with the ASGP-R. Such a receptor has been already proposed as a target for exogenous molecules, specifically in the case of hepatocytes, for diagnostic and therapeutic purposes. The DOCK5.2 program was used to search optimal locations of the above ligands of interest into CRD binding site and to roughly estimate interaction energies. Finally, the binding ΔG of theoretical protein-ligand complexes was estimated by using the DelPhi program in which the solvation free energy is accounted for with a continuum solvent model, by solving the Poisson-Boltzmann equation. The structure analysis of the obtained complexes and their ΔG values suggest that one of the sugar monomers of interest shows the desired characteristics.     

水热法制备SrF2:Ce3+,Tb3+荧光粉及其发光性质研究

采用水热法合成了具有立方相结构的Ce3+、Tb3+共掺杂的SrF2发光材料SrF2:Ce3+,Tb3+,利用粉末X-射线衍射( XRD)对其结构进行了表征,并研究了掺杂量、水热反应时间、激发波长对SrF2:Ce3+,Tb3+发光性质的影响.荧光光谱研究结果表明,SrF2:Ce3+,Tb3+在254 nm波长紫外光激发下...     

Carbon Nanofiber Supported Cobalt Catalysts for Fischer–Tropsch Synthesis with High Activity and Selectivity

Platelet and fishbone carbon nanofibers (CNFs) have been used as supports for cobalt Fischer–Tropsch catalysts. The activity and selectivity of the CNF supported catalysts have been studied at 483 K, 20 bar, and H₂/CO = 2.1, and compared with corresponding activity and selectivity for α-Al₂O₃ and γ-Al₂O₃ supported cobalt catalysts. The platelet CNF supported catalyst has demonstrated high activity and high selectivity to C₅₊ hydrocarbons, with activity comparable with Co/γ-Al₂O₃ and selectivity comparable with Co/α-Al₂O₃.     

熔盐法对黄粉YAG:Ce~(3+)表面改性的探讨

采用熔盐法制备了YAG:Ce3+黄色荧光粉,并与传统的固相-助熔剂法制备的相应粉体在晶体的形貌和外表特征及对发光性能的影响作了比较和分析。研究结果表明,熔盐法能有效改善荧光粉晶体的形貌和外表特征,制备出的荧光粉表面更光滑,分布更均匀,颗粒趋于近球形生长。     

高选择性合成1-甲氧基-2-丙醇固体催化剂的筛选和催化作用

对碱土金属氧化物和两性氧化物等10种氧化物作为合成1 甲氧基 2 丙醇固体催化剂进行了催化性能筛选。发现在碱土金属氧化物MgO、CaO和BaO中,中强碱MgO具有较高的环氧丙烷(PO)转化率(71 07%)和1 甲氧基 2 丙醇(PPM)选择性(92 53%)。在两性氧化物中,ZnO具有较高的PO转化率(55 26%)和PPM选择性(92 37%)。系统考察了反应温度、催化剂用量、反应时间和原料摩尔配比对MgO、ZnO的催化作用特点的影响,发现MgO在催化性能和1 甲氧基 2 丙醇选择性方面表现出的综合性能优于其他催化剂。     

新型Schiff碱荧光传感器的合成及其对Ni~(2+)高选择性的识别

合成了新型荧光分子对二甲氨基苯甲醛缩4-氨基安替比林西弗碱,产物结构经~1H NMR、IR和质谱确证。通过了荧光光谱滴定的方法,结果显示,只有在Ni~(2+)的存在下,荧光强度显著增强,同时荧光强度也随着Ni~(2+)浓度的增大而增强,证明其对Ni~(2+)有较强的选择性识别作用。