基于咔唑衍生物的荧光化学传感器的合成及其对金属离子的选择性识别性能

以咔唑为原料合成了2个荧光化学传感器,所得化合物的组成和结构经元素分析以及质谱、红外光谱、核磁共振氢谱验证.通过在25℃下进行荧光光谱滴定,研究了传感器在体积比为1∶1的二甲基亚砜/水缓冲溶液[三羟甲基氨基甲烷盐酸盐(Tris-HCl),pH=7.4]中对Cu2+和Fe3+的选择性识别作用.结果表明,所合成的传感器与Cu2+和Fe3+形成1∶1的配合物并导致荧光猝灭,并对Cu2+离子和Fe3+离子具有较高的选择性识别和荧光传感性能.     

水溶液中对Cr~(3+)高选择性荧光化学传感器的研究

设计了一种新型的Cr3+荧光化学传感器.通过荧光光谱滴定实验研究了其对Li+,Na+,K+,Zn2+,Co2+,Ni 2+,Cu2+,Fe2+,Mn2+,Al 3+,Fe3+和Cr3+等不同金属离子的选择性识别能力,结果表明,该传感器在生理pH=7.4的HEPES中对Cr3+表现出较高的选择性,并与Cr3+形成1∶1配合物,主客体相互作用荧光猝灭的络合常数为(7.80±0.34)×103.     

两个新型1,3-硒唑酰腙的合成及其对醋酸根离子的特性荧光识别

设计合成了2个1,3-硒唑酰腙分子(SAF1和SAF2),并通过红外光谱(IR)和核磁共振谱(NMR)等对其进行了结构表征。 通过紫外-可见光谱(UV-Vis)和荧光光谱,利用探针SAF1和SAF2分别对9种常见的阴离子进行了监测。 结果发现,当加入醋酸根离子(AcO^-)时,在UV-Vis中,探针SAF1和SAF2分别在500 nm和414 nm处出现一个新的吸收峰,探针SAF1对应的溶液颜色由淡黄色变为红色,探针SAF2对应的溶液颜色由浅黄色变为黄色,可实现裸眼识别;在荧光光谱中,417 nm附近产生强的荧光发射峰,且具有荧光开启(turn-on)功效,AcO^-的最低检测限达10^-5 mol/L,2个分子与AcO^-的结合常数分别为3.03×10⁴和1.42×10⁴ L/mol,说明化合物SAF1和SAF2有望作为AcO^- 的特性荧光识别探针。     

Ratiometric and selective fluorescent sensor for CuII based on internal charge transfer (ICT)

A Cu(II)-sensing, ratiometric, and selective fluorescent sensor 1, N-butyl-4,5-di[(pyridin-2-ylmethyl)amino]-1,8-naphthalimide, was designed and synthesized on the basis of the mechanism of internal charge transfer (ICT). In aqueous ethanol solutions of 1, the presence of Cu(II) induces the formation of a 1:1 metal-ligand complex, which exhibits a strong, increasing fluorescent emission centered at 475 nm at the expense of the fluorescent emission of 1 centered at 525 nm. [structure: see text]     

A highly selective and sensitive fluorescent chemosensor for Zn^2＋

A new selective Zn^2＋ fluorescent chemosensor, o-vanillin-4-ethoxybenzoylhydrazone （1）, was designed and prepared. Free 1 mainly displayed very weak fluorescence at 480 nm upon excitation at 403 nm. It displayed high selectivity for Zn^2＋ and had a 518- fold fluorescent enhancement upon binding of Zn^2＋, while the other cation ions had only little influence on the fluorescence of 1. Mechanism of enhancement of l＇s fluorescence by Zn^2＋ was briefly discussed.     

A Zn2+-specific turn-on fluorescent probe for ratiometric sensing of pyrophosphate in both water and blood serum

A novel fluorescent sensor composed of a naphthalene functionalized tetraazamacrocycle ligand 3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(15),11,13-triene-3-methyl naphthalene (1) and Zn(2+) has been designed and prepared, which can be utilized for selective and ratiometric sensing of pyrophosphate (PPi) over other phosphate-containing anions in aqueous solution at physiological pH. Notably, the water soluble 1 itself also exhibits a selective enhanced fluorescent response to Zn(2+), and the complex 1-Zn(2+) thus formed eventually fulfils the synergic Zn(2+) coordination-altered strategy with PPi. Furthermore, the ratiometric sensing of 1-Zn(2+) towards PPi performed well even in blood serum milieu. Finally, the sensor 1-Zn(2+) was successfully employed to monitor a real-time assay of inorganic pyrophosphatase (PPase) by means of ratiometric fluorescent measurements for the first time.     

N-(9-蒽甲基)-L-酪氨酸盐酸盐的合成及其对阴离子的分子识别

利用荧光基团9-蒽醛与L-酪氨酸反应,合成了荧光主体N-(9-蒽甲基)-L-酪氨酸盐酸盐;采用荧光光谱方法检测了荧光主体与不同阴离子之间的识别作用;通过加入不同摩尔比的配体确定了主体与配体之间识别的最佳摩尔配比.结果表明,配置浓度为5×10-5mol·L-1的Cr2O2-7溶液后,用微量进样器加入100μL浓度为1×1...     

亚乙烯基嘌呤核苷衍生物的合成、荧光和生化性质的研究进展

综述了亚乙烯基核苷衍生物(1,N⁶-亚乙烯基腺苷, N²,3-亚乙烯基腺苷, 1,N²-亚乙烯基鸟苷, N²,3-亚乙烯基鸟苷, 1,N⁶-亚乙烯基脱氧腺苷, 1,N²-亚乙烯基-2'-脱氧鸟苷, N²,3-亚乙烯基-2'-脱氧鸟苷)的研究进展, 讨论了其荧光性质和生物活性的应用, 展望了新型荧光扩环核苷衍生物的合成及其在荧光探针和高效药物筛选方面的研究前景.     

KINETICS OF BACTERIAL BIOLUMINESCENCE AND THE FLUORESCENT TRANSIENT

Abstract— The addition of FMNH₂ to Vibrio harveyi luciferase at 2°C in the presence of tetradecanal results in the formation of a highly fluorescent transient species with a spectral distribution indistinguishable from that of the bioluminescence. The bioluminescence reaches maximum intensity in 1.5 s and decays in a complex manner with exponential components of 10^-1s^-1, 7 × 10^-3s^-1, and 7 × 10 ⁴s^-1. The fluorescent transient rises exponentially at 7 × 10^-2s^-3 and decays at 3 × 10^-4s^-1. The slowest bioluminescence component, comprising the bulk of the bioluminescence, decays at twice the rate of the fluorescent transient under all variations of reaction conditions: concentration of reactants, temperature 2–20°C, and aldehyde chain length—decanal, dodecanal and tetradecanal. The activation energy for both the slowest bioluminescence decay and the transient fluorescence decay is 80 kJ-mol^-1. An energy transfer scheme is proposed to explain the results where two distinct chemically energized species utilize the fluorescent transient as emitter for the slower bioluminescences, and for the faster process a fluorophore present in the protein preparation. Kinetic observations suggest that typical preparations of V. harveyi luciferase comprise 15% active protein.     

原位反应法制备丙烯酸钐/丁腈橡胶复合材料及其荧光性能研究

通过两种不同的原位反应制备了丙烯酸钐/丁腈橡胶[Sm(AA)₃/NBR]复合材料.SEM和TEM结果表明,原位反应使稀土配合物的粒径减小,且均匀地分散在基体聚合物中.荧光分析表明,以260nm作为激发波长时,两种复合材料在379nm(⁴D_1/2,⁶P_7/2→⁶H_5/2)和418nm(⁴L_15/2,⁴G_1/2→⁶H_5/2)处出现了与自由离子基本相同的发射峰(374和390nm),属于受配体微扰的中心离子发光.原位反应制备的复合材料在不同激发波长下的荧光强度均比非原位反应体系的荧光强度高.随着稀土含量的增加,其荧光强度增加,至稀土质量分数为30%时出现荧光猝灭.     

Highly effective fluorescent and colorimetric sensors for pyrophosphate over H2PO4- in 100% aqueous solution

[Structure: see text]. This study demonstrated that Zinpyr-1*Zn2+ acts as a fluorescent and colorimetric sensor for pyrophosphate at pH 7.4. In addition, Zinpyr-1*Cu2+ and DIARB-1*Cu2+ complexes were found to act as selective fluorescent sensors for pyrophosphate. Furthermore, the chemosensors Zinpyr-1*Zn2+ and Zinpyr-1*Cu2+ show highly selective and ratiometric fluorescence changes for pyrophosphate compared with H2PO4-.     

Resonance enhancement of two-photon absorption in fluorescent proteins

We measure two-photon absorption (2PA) spectra of wild-type green fluorescent protein, cyan fluorescent protein, and monomeric red fluorescent protein in absolute cross section values in a wide spectral range (lambda2PA = 550 - 1300 nm), and find, for the first time to our knowledge, a new S0 --> Sn 2PA transition in all three proteins in the short-wavelength region. This transition is strongly resonantly enhanced, showing 2PA cross section values of approximately 20-160 GM, which are at least 2-4 times higher than those measured in the lowest energy (S0 --> S1) transition of corresponding proteins. We also show that the change of permanent dipole moment upon S0 --> S1 excitation (|Deltamu10|) can be deduced from 2PA cross section, providing a new tool for fast evaluation of |Deltamu10| in physiological conditions.     

Fluorescent probe for copper(II) ion based on a rhodamine spirolactame derivative, and its application to fluorescent imaging in living cells

A fluorescent probe for Cu(II) ion is presented. It is based on the rhodamine fluorophore and exhibits high selectivity and sensitivity for Cu(II) ion in aqueous methanol (2:8, v/v) at pH 7.0. The response is based on a ring opening reaction and formation of a strongly fluorescent 1:1 complex. The response is reversible and linear in the range between 50?nM and 900?nM, with a detection limit of 7.0?nM. The probe was successfully applied to fluorescent imaging of Cu(II) ions in HeLa cells.

稀土螯合物发光体LB膜的研究(I)

稀土有机配合物的发光研究近年来取得了可喜的近展.铕(Ⅲ)、铽(Ⅲ)、钐(Ⅲ)与β-二酮(β-dik),三正辛基氧化膦(TOPO)所形成的螯合物,以及它们的硝酸盐与邻菲咯啉(Phen)所形成的螯合物都是高光效的发光体,有广阔的应用前景,在某些方面已获得应用.如能把这些具有发光功能的稀土螯合物组装成有序的分子组合体,则很可能在分子光学技术,光电子技术等领域发挥重要作用.如何组装?本文用LB 膜技术,通过交替成膜或混     

8-Hydroxyquinoline derivative as a fluorescent chemosensor for zinc ion.

8-Hydroxyquinoline derivative 1 as a fluorescent chemosensor for Zn2+ was synthesized. Because Cd2+ is often found with Zn2+ in the environment and can form fluorescent complexes with chelating fluorophores, a potentially important property of chemosensors for Zn2+ is their selectivity for Zn2+ over Cd2+. The Zn2+ or Cd2+ complexes of 1 gave an emission band from the 1:1 complex, but the fluorescence intensity for Cd2+ was a half of that for Zn2+. Ligand 1 is suited for use as a fluorescent chemosensor for Zn2+.     

A versatile water soluble fluorescent probe for ratiometric sensing of Hg2+ and bovine serum albumin

A novel tetraazamacrocycle fluorescent sensor (6-(1-(dimethylamino)-5-naphthalene sulfonyl)-3,6,9,15-tetraazabicyclo[9.3.1] pentadeca-1(15),11,13-triene, 1) has been designed and prepared, which can be utilized for selective and ratiometric sensing of Hg(2+) and bovine serum albumin (BSA) with two different responsive modes in aqueous solution at physiological pH (50 mM Tris-HCl, pH 7.6). Above 0.5 ppb Hg(2+) can be discerned by coordination with 1 and the emission color changes enable 1 to be applied to a fast Hg(2+) test paper assay. Sensor 1 has also been demonstrated to be easily cell-penetrable and applicable for Hg(2+) imaging in living cells. Imaging of BSA in the gel using SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis) stained in the medium containing 1 verified that the binding of 1 and BSA was successful in the presence of nonprotein substances. The linear range of 1 towards BSA utilizing ratiometric fluorescent calibration via noncovalent interaction in solution is 0-100 μg mL(-1) with a detection limit of 1 μg mL(-1), and has been successfully employed to determine the albumin concentration in blood serum by means of ratiometric fluorescent measurements for the first time. Finally, sensor 1 behaves as a fluorescent molecular switch composed of triple logic gates upon chemical inputs of Hg(2+) and BSA, which potentially provides intelligent diagnostics for Hg(2+) contaminated serum on the nanoscale.     

Fluorescence "Turn-On" chemosensor for the selective detection of beryllium

A new fluorogenic method for selective and sensitive determination of beryllium using 2,6-diphenyl-4-benzo-9-crown-3-pyrane (DBCP) was developed. The proposed fluorescent probe undergoes fluorescent emission intensity enhancement upon binding to beryllium ions in MeOH/H(2)O (70:30, v/v) solution. The fluorescence enhancement of DBCP is attributed to a 1:1 complex formation between DBCP and Be(2+) ion, which has been utilized as the basis for selective detection of Be(2+) ion. With the optimum condition described, the fluorescence enhancement at 531 nm was linear to the concentration of beryllium in the range of 1.6×10(-8)-1.6×10(-7) M and a detection limit of 1.5×10(-9) M. The fluorescent probe exhibits high selectivity for Be(2+) ion over the other common mono, di- and trivalent cations.     

Membrane-permeable and -impermeable sensors of the Zinpyr family and their application to imaging of hippocampal zinc in vivo

Esterification of fluorescent biosensors is a common strategy used to trap probes within the cell. Zinpyr-1 (ZP1) is a fluorescein-based bright fluorescent sensor for divalent zinc that is cell permeable without prior modification. We describe here the synthesis and characterization of ZP1 sensors containing a carboxylic acid or ethyl ester functionality at the 5 or 6 position of the fluorescein. The presence of an electronegative carboxylate decreases the proton-induced background fluorescence of the probe by lowering the pKa of the benzylic amines responsible for fluorescence quenching. The charged species ZP1(6-CO2-) is membrane-impermeant, whereas the permeability of the neutral ZP1(5/6-CO2Et) is similar to that of the parent sensor. Intracranial microinfusion of ZP1(6-CO2Et) into rat hippocampus produces reduced staining of vesicular zinc in neuropil and very clear delineation of zinc-positive injured neuronal somata and dendrites as compared with ZP1.     

Hydrogen peroxide-induced deacetylation of acetyl resorufin as a novel indicator reaction for fluorometric detection of glucose using only glucose oxidase

Hydrogen peroxide (H2O2)-induced deacetylation of non-fluorescent acetyl resorufin (1) to fluorescent resorufin (2) as a novel indicator reaction for fluorometric detection of glucose using only glucose oxidase (GOD) is described. When a 1:1:1 mixture of 1 (in CH3CN), glucose, and GOD (each in pH 7.4 phosphate buffer) was incubated at 25 degrees C under aerobic conditions, the resulting solution turned yellow to fluorescent pink due to 2. The formation of 2 was markedly retarded on incubation under anaerobic conditions. When a mixture of 1 and H2O2 was incubated under aerobic conditions, the formation of 2 was noted as in the case of the enzymatic reaction of 1. These results demonstrated that the observed color change is brought about through deacetylation of 1 to 2 induced by H2O2 generated in GOD-catalyzed oxidation of glucose. With regard to the fluorometric traces of the enzymatic reaction with 1 (0.2 mM), GOD (0.5 mg/ml), and glucose at 25 degrees C, fluorescence intensity exhibited a linear relationship against glucose concentration between 0.2 and 2.0 mm, with a correlation coefficient of 0.997. Neither ascorbic acid, uric acid, nor bilirubin significantly interfered with the transformation of 1 to 2 through GOD-catalyzed oxidation of glucose.     

2-(2-羟基-5-氯苯基)-1H-苯并咪唑-铜(Ⅱ)配合物作为NO荧光探针的初探

常温下合成了2-(2-羟基-5-氯苯基)-1H-苯并咪唑荧光化合物和其二价铜离子的配合物,并对配合物的结构和稳定性进行了表征,用荧光光谱、质谱、红外光谱等研究了配合物与NO反应的机理.结果表明,该配合物与NO的反应具有高度的选择性,不受其他常见干扰分子的影响.配合物应用于脂多糖(LPS)激活的小鼠巨噬细胞中NO的测定,能够得到具有较好分辨率的荧光成像结果.