共查询到20条相似文献,搜索用时 93 毫秒
1.
双光子荧光显微成像兼具诸如近红外激发、暗场成像、避免荧光漂白和光致毒、定靶激发、高横向分辨率与纵向分辨率、降低生物组织吸光系数及降低组织自发荧光干扰等特点而显著地优于单光子荧光显微成像,为生命科学研究提供了更为锐利的工具。而用于像离子的含量及其对生理的影响、离子参与的生理活动机制、离子与分子的作用、特定分子的分布及其相互作用等方面研究的双光子荧光探针,是实现成像的关键。双光子荧光探针的研究旨在促进双光子荧光显微镜应用的发展,促进生命科学、医学科学的快速发展,同时也带动双光子荧光探针所隶属的化学这一学科的发展。因此对双光子荧光探针的研究具有重要的理论和实践意义。该文综述了双光子荧光显微成像的优点、双光子荧光探针设计的原理及双光子荧光探针在离子分析方面的应用,并展望了这类荧光探针的发展趋势与应用前景。 相似文献
2.
3.
4.
5.
6.
7.
8.
9.
10.
发展了一种合成荧光银纳簇的新方法。采用易得的生物蛋白材料蛋清,无需其他还原剂,调节pH值后,通过最简便的一锅孵化法制备了荧光银纳簇。这种合成方法类似于自然界的生物矿化现象:生物分子捕获无机离子,在功能性分子作用下进行矿化过程。高分辨透射电镜分析表明纳簇的粒径小于2 nm。该合成方法环保经济。紫外-可见吸收光谱和荧光发射光谱分析表明这种银纳簇能快速响应氰离子,导致吸光度减弱,并伴随荧光猝灭。基于此原理建立了一种检测氰离子的荧光传感新方法,此分析方法显示良好的线性范围和选择性,较高的灵敏度。检测限为1.2 μmol·L-1,低于世界卫生组织推荐的饮用水标准(氰化物浓度不高于2.7 μmol·L-1)。 相似文献
11.
Gun-Joong Kim 《Tetrahedron letters》2010,51(21):2914-133
A simple aldehyde-functionalized coumarin (1) was utilized as a doubly activated Michael acceptor type of chemodosimeter for cyanide in water. The probe has shown a selective and sensitive response to the cyanide anion over other various anions through the Michael addition reaction of the cyanide to 1. When cyanide anions were added, the prominent color changes as well as fluorescence changes of 1 were observed so that millimolar concentrations of cyanides were detectable by the naked eye. 相似文献
12.
Ivan Pietro OliveriSanto Di Bella 《Tetrahedron》2011,67(48):9446-9449
A new fluorescent probe, based on an amphiphilic Schiff-base zinc(II) complex, 1, for the sensitive detection of some important classes of alkaloids is presented. It exhibits optical absorption changes and fluorescence enhancement upon formation of 1:1 1·alkaloid adducts. Four diverse classes of alkaloids, represented by their basic structures and related representative prototypes, are investigated, through the study of optical and binding properties of 1·alkaloid adducts. It is found that the chromogenic and fluorogenic complex 1 is selective between these classes of alkaloids in the micromolar range, with a limit of quantification of 0.40 μM for nicotine and 0.43 μM for cinchonine. 相似文献
13.
A colorimetric and fluorescent cyanide probe based on 7-(trifluoroacetamino)coumarin has been prepared. This structurally simple probe displays rapid response and high selectivity for cyanide over other common anions in the aqueous solution. The sensing of cyanide was performed via the nucleophilic attack of cyanide anion to carbonyl of the probe with a 1:1 binding stoichiometry, which could be confirmed by Job’s plot, 1H NMR, and MS studies. DFT/TDDFT calculations support that the fluorescence enhancement of the probe is mainly due to the ICT process improvement. The detection limit of the fluorescent assay for cyanide is as low as 0.3 μM in a rapid response of less than 30 s. Thus, the present probe should be applicable as a practical system for the monitoring of cyanide concentrations in aqueous samples. 相似文献
14.
Gun-Joong Kim 《Tetrahedron letters》2010,51(1):185-133
A new α,β-unsaturated nitro group and coumarin conjugate-based fluorescent chemodosimeter 1 was developed for the selective detection of cyanide anions. The chemodosimeter has shown a selective and sensitive response to cyanide anions over other various anions through a nucleophilic aromatic substitution reaction of the cyanide to 1. When cyanide anions were added, the enhanced fluorescence intensity as well as the color changes of 1 was observed so that micromolar concentrations of cyanides were detectable by the naked eye. 相似文献
15.
Qiu-Juan Ma Xiao-Bing Zhang Xu-Hua Zhao Guo-Jiang Mao Ru-Qin Yu 《Analytica chimica acta》2010,663(1):85-1197
A fluorescent probe 1 for Hg2+ based on a rhodamine-coumarin conjugate was designed and synthesized. Probe 1 exhibits high sensitivity and selectivity for sensing Hg2+, and about a 24-fold increase in fluorescence emission intensity is observed upon binding excess Hg2+ in 50% water/ethanol buffered at pH 7.24. The fluorescence response to Hg2+ is attributed to the 1:1 complex formation between probe 1 and Hg2+, which has been utilized as the basis for the selective detection of Hg2+. Besides, probe 1 was also found to show a reversible dual chromo- and fluorogenic response toward Hg2+ likely due to the chelation-induced ring opening of rhodamine spirolactam. The analytical performance characteristics of the proposed Hg2+-sensitive probe were investigated. The linear response range covers a concentration range of Hg2+ from 8.0 × 10−8 to 1.0 × 10−5 mol L−1 and the detection limit is 4.0 × 10−8 mol L−1. The determination of Hg2+ in both tap and river water samples displays satisfactory results. 相似文献
16.
Health or environmental issue caused by abnormal level of metal ions like Zn2+ or Cd2+ is a worldwide concern. Developing an inexpensive and facile detection method for Zn2+ and Cd2+ is in urgent demand. Due to their super optical properties, fluorescent quantum dots (QDs) have been developed as a promising alternative for organic dyes in fluorescence analysis. In this study, a CdTe QDs-based sensitive and selective probe for Zn2+ and Cd2+ in aqueous media was reported. The proposed probe worked in fluorescence “turn-on” mode. The initial bright fluorescence of CdTe QDs was effectively quenched by sulfur anions (S2−). The presence of Zn2+ (or Cd2+) can “turn-on” the weak fluorescence of QDs quenched by S2− due to the formation of ZnS (or CdS) passivation shell. Under optimal conditions, a good linear relationship between the fluorescence response and concentration of Zn2+ (or Cd2+) could be obtained in the range from 1.6 to 35 μM (1.3–25 μM for Cd2+). The limit of detection (LOD) for Zn2+ and Cd2+ were found to be 1.2 and 0.5 μM, respectively. Furthermore, the present probe exhibited a high selectivity for Zn2+ and Cd2+ over other metal ions and was successfully used in the detection of Zn2+ or Cd2+ in real water samples. 相似文献
17.
A new two-photon fluorescent probe, ADNO, for nitric oxide (NO) based on intramolecular photoinduced electron transfer (PET) mechanism d/splays a rapid response to NO with a remarkable fluorescent enhancement in PBS buffer. The excellent chemoselectivity of ADNO for NO over other ROS/RNS (reactive oxygen species or nitrogen species) and common metal ions was observed. Moreover, ADNO has been successfully applied in fluorescence imaging of NO of living cells using both one-photon microscopy (OPM) and two-~hoton microscopy (TPM), 相似文献
18.
《Journal of Coordination Chemistry》2012,65(21):3857-3867
Fluorescent Red GK, a commercially available coumarin-based dye, was developed as a “turn-off” fluorescent probe for detection of Cu2+ in aqueous solution. It exhibited high selectivity and sensitivity at room temperature. Upon addition of Cu2+, the strong fluorescence of Fluorescent Red GK was severely quenched and its color changed from orange to colorless under illumination with a UV lamp; the color of the solution also changed from pink to colorless. So, it can be used as a specific colorimetric and fluorescent probe for Cu2+ with a detection limit as low as 0.0634?μM. 相似文献
19.
20.
Lun Song Xu-Dong Sun Yu Ge Yu-Hua Yao Jie Shen Wei-Bing Zhang Jun-Hong Qian 《中国化学快报》2016,27(12):1776-1780
A polarity-sensitive fluorescent probe MNP was rationally designed and synthesized with naphthalimide as the fluorophore and maleimide as the receptor for thiols. MNP is weakly fluorescent due to the photoinduced electron-transfer(PET) from the fluorophore to the receptor, and it displays evidently solvatochromic UV–vis and fluorescence spectra: the emission shifted from 495 nm in n-hexane to545 nm in phosphate buffer solution. Michael addition reaction between thiols and the maleimide in MNP inhibited the PET process, which led to about eight-fold fluorescence enhancement. In addition,MNP showed highly sensitivity to mercapto-containing proteins and it could detect as low as 20.4 mg/m L of BSA in PBS. MNP has potential in fluorescent imaging of thiols in living cells. 相似文献