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101.
《Journal of Coordination Chemistry》2012,65(5):921-928
A new fluorescent derivative (1) containing coumarin exhibits Fe(III)-selective strong yellow-green fluorescence in ethanol. This compound could be used as an “off-on” chemosensor and allow the detection of Fe3+ by monitoring changes in absorption and fluorescence spectra. Upon addition of Fe3+, an overall emission change of 125-fold was observed. High selectivity and sensitivity were observed over other metal ions, mainly due to the spirolactam ring-opening power of Fe3+. The detection limit was as low as 5.6?ppb. Photo-induced electron transfer, coupled with intramolecular charge transfer are proposed to account for the observed spectral response. 相似文献
102.
103.
采用点击化学偶联法对荧光二氧化硅纳米粒子表面进行叶酸功能化修饰,构建了一种叶酸受体靶向的荧光纳米探针,并成功用于肿瘤细胞的成像研究.首先通过St?ber法制备包裹钌联吡啶的荧光二氧化硅纳米粒子(RSiNPs),然后利用叠氮化硅烷偶联剂(Az-PTES)的水解反应在其表面引入叠氮基团,最后通过点击化学反应将炔丙基叶酸衍生物偶联到粒子表面.利用红外光谱对其偶联前后的叠氮基特征峰(2105 cm-1)进行表征,证实了叶酸功能化的荧光纳米探针(RSiNPs-Folate)已被成功制备.在生理pH条件下,以458 nm为激发波长,RSiNPs-Folate在601 nm处发射较强的红色荧光,且光稳定性较好.细胞成像结果表明,这种叶酸受体靶向的荧光纳米探针能够有效地标记叶酸受体呈阳性的人宫颈癌细胞(HeLa),而叶酸受体呈阴性的人肺癌细胞(A549)未观察到明显的荧光.叶酸竞争性结合实验证明了这种叶酸受体介导的肿瘤细胞成像机制.此探针能够实现混合细胞体系中HeLa细胞的选择性识别与荧光成像.与酰胺化反应偶联叶酸相比,这种点击功能化的纳米探针的合成方法简单、反应条件温和、产率高,可用于不同肿瘤细胞的荧光标记与成像. 相似文献
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105.
Lujuan Liao Zhenjie Li Wei Hu Yan Huang Bu-min Liu Lisheng Wang Mian Wang Jianyi Wang 《Tetrahedron letters》2018,59(27):2683-2687
A novel H2S-responsive fluorescent probe Rh-Lyso-H2S has been designed and synthesized. The Rh-Lyso-H2S shows high sensitivity and selectivity toward H2S, with a limit of detection of 3.36?×?10?7?M. The reason is that Rh-Lyso-H2S changed from a stable non-conjugated closed-ring lactone conformation with weak fluorescence to a conjugated open-ring conformation with strong fluorescence in the presence of H2S. The Rh-Lyso-H2S has a good lysosome-targeting capacity and is used to detect lysosomal H2S in living cells, which is driven via the protonation of its basic morpholine moiety by acidic lysosomes. Rh-Lyso-H2S is triggered by H2S via removing the thiophenecarboxylate group, and the corresponding activated mechanism of Rh-Lyso-H2S toward H2S is proposed. 相似文献
106.
Sunisa Boontom Kanokthorn Boonkitpatarakul Mongkol Sukwattanasinitt Nakorn Niamnont 《Tetrahedron》2017,73(17):2483-2487
A novel thiosemicarbazone fluorophore (3) was successfully synthesized in 3 steps via Sonogashira coupling and Knoevenagel condensation using baker's yeast (Saccharomyces cerevisiae) as a biocatalyst. Compound 3 contains triphenylacetylene, which acts as a fluorophore, and thiosemicarbazone, which acts as a copper probe. Compound 3 exhibited highly selective detection of Cu2+ ions based on photoinduced electron transfer (PET) in 10 mM HEPES buffer pH 7.4/propylene glycol (70% (v/v)). A linear relationship was observed for Cu2+ concentrations between 0.1 nM and 10 μM, and the detection limit of the method was 0.14 nM. Additionally, 3 was utilized to detect Cu2+ in wastewater with satisfactory results, which highlighted its potential for real sample applications. 相似文献
107.
选择壳聚糖水溶液作为唯一反应物,利用简单方便的微波原位法制备碳点/壳聚糖荧光复合物,该复合物无需经过产物分离提纯等步骤就能够直接进行后续应用.测试结果表明,碳点/壳聚糖复合物溶液呈黄棕色,透明均一,在365 nm紫外光下显示出明显的蓝色荧光.此外,碳点/壳聚糖复合物中的碳点分散良好,尺寸比较均一.重要的是,该碳点/壳聚糖复合物具有新的综合性能特点,即不仅被赋予了碳点的多色荧光性能,而且还保留了壳聚糖的成膜性能和p H刺激响应性能,可以十分方便地直接进行多种应用,包括利用该复合物制备荧光复合膜和复合球,以及采用电沉积方法制备具有特定形状的荧光涂层,还可以直接应用于细胞成像.因此,这种微波原位法制备的碳点/壳聚糖复合物在荧光材料、荧光涂层、生物成像和生物标记等领域具有潜在的应用价值. 相似文献
108.
109.
Biphenyl derivative N-allyl-N′-(4′-nitro[1,1′-biphenyl]-4-yl)thiourea (BP1) was synthesized as a functional fluorescent sensor for protons and their photophysical properties were studied. The influence of environment protonation on photophysical properties of the biphenyls in solutions was investigated using UV absorption, steady-state and time-resolved fluorescence spectroscopy. Semi-empirical and DFT calculations and optimization of the molecular structure of the biphenyl derivatives in vacuum, in polar solvents and in a proton-rich environment were conducted using the HyperChem, Amsol and Gaussian3 software package. Fluorescence quenching with addition of acidic acid was observed and the Stern-Volmer quenching rate constant was about 3.0×109 M−1 s−1. Intermolecular hydrogen bonds formations by the protons with the sulphur being substituted to the biphenyls generate charge movement and strong increase (×5) of the dipole moment of the fluorophore. 相似文献
110.
Using D-proline (D-Pro) as the reducing agent and capper, D-Pro@AuNCs was rapidly constructed. Its fluorescence could be quenched by AuNPs. Due to the electrostatic interaction between anticancer drug Raltitrexed (RTX) and AuNPs induced fluorescence "turn-on" principle, the resultant fluorescent probe exhibited good selectivity and sensitivity for detecting RTX in rat serums. 相似文献