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1.
Sung Woo Hong 《Polymer》2008,49(19):4180-4187
A fluorescence resonance energy transfer (FRET) sensor, which has a FRET donor and an acceptor attached to each chain end of pH-sensitive polysulfonamide, is synthesized and its pH sensitivity is examined in terms of the FRET efficiency. This polymeric sensor exhibits an instantaneous conformation change from coil to globule at a specific pH, which results in the drastic on-and-off FRET efficiency. To detect a specific pH region, sulfadimethoxine and sulfamethizole are selected among various sulfonamides since their pKa values are in the physiological pH. For tuning the emission color arising from FRET, 7-hydroxy-4-bromomethyl coumarin and coumarin 343 are used as a FRET donor and an acceptor, respectively, for a blue-to-green FRET sensor, and fluorescence amine isomer I and rhodamine B are used for a green-to-red FRET sensor. Each sensor shows a distinct color change from the emission wavelength of FRET donor to the emission wavelength of FRET acceptor, which well explains their feasibility as a useful optical sensor. 相似文献
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Based on the nucleophilic aromatic substitution reaction mechanism, a new highly selective probe for cysteine (Cys), N-butyl-4-bromo-3-nitro-1,8-naphthalimide (1), was designed and synthesized. The probe displayed a remarkable (58 nm) red-shift in the absorption spectra and the color changes from colorless to yellow upon reaction with Cys. The probe could detect Cys quantitatively in the range of 0-0.9 mM by both normal and ratiometric absorption spectrometry methods. Moreover, 1 could also serve as a “naked-eye” probe for Cys with a minimum detectable concentration of approximately 50 μM. 相似文献
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基于罗丹明B合成了两种有机荧光探针用来检测Cu~(2+)。以罗丹明B与3-甲氧基苯酰肼、水杨酰肼为原料合成了两种探针,命名为Rh1、Rh2,分别与Cu~(2+)以及其它金属离子溶液反应,观察溶液的颜色变化,分别测定其紫外及荧光吸收光谱。Rh1、Rh2加入铜离子溶液后,溶液由无色到粉红色的显著颜色变化,与其它金属离子比较在400~700nm有较明显的紫外-可见吸收和荧光增强。两种荧光探针能够有效的跟Cu~(2+)结合,从紫外-可见吸收光谱和荧光光谱可以看出此探针显示出选择性的、敏感的荧光增强反应,表现出对Cu~(2+)良好的选择性。 相似文献
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The fluorescence quenching effect of polymeric carbon nitride-based materials can be efficiently applied to the rapid detection of Hg2+. Herein, we chose dicyandiamide and sodium hypophosphite as precursors to prepare bulk phosphorous-doped polymeric carbon nitride through thermal polycondensation, and then a one-step hydrothermal treatment caused the depolymerization of the bulk products and the formation of the nanorod-like structures. The depolymerization resulted in the good aqueous colloidal stability of the polymeric carbon nitride-based derivative, and phosphorus-doping significantly improved its fluorescence. More terminal amino and abundant surface hydroxyl groups led to the enhanced selective fluorescence quenching of Hg2+ by the depolymerized products. Therefore, the depolymerized phosphorous-doped polymeric carbon nitride with a fluorescence quantum yield of 23.2% showed excellent Hg2+ detection capability. The limit of detection of the depolymerized polymeric carbon nitride to Hg2+ can reach 0.74 nmol L?1. And the depolymerized products also showed good accuracy in the Hg2+ detection of shrimp samples. This work broadens the scope of polymeric carbon nitride-based heavy metal ion fluorescent probes, and provides a new roadmap for the highly selective determination of Hg2+. 相似文献
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采用6-甲氧基苯并噻唑-2-羟基喹啉作为双光子荧光团、硼酸酯作为过氧化氢(H2O2)识别基团,合成比率型检测H2O2的双光子荧光探针{6-甲氧基-2-[6-(4,4,5,5-四甲基-1,3,2-二氧硼杂环戊烷-2-基)喹啉-2-基]苯并[d]噻唑}(MQH2O2)。利用荧光光谱和双光子荧光光谱对探针进行H2O2响应能力的评估,结果显示探针具有良好的H2O2比率响应(30 min内比率信号增强约25.4倍、检出限低至38.6 nmol/L)和双光子性质(最大双光子荧光活性截面为150 GM)。通过双光子共聚焦成像完成了细胞和大脑组织成像,结果表明该探针能够实现脑卒中诱导细胞氧化应激的原位成像分析。 相似文献
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A novel fluorescent sensor based on thiooxorhodamine B has been prepared to detect Hg2+ in aqueous buffer solution. It demonstrates high selectivity for sensing Hg2+ with about 383-fold enhancement in fluorescence emission intensity and micromolar sensitivity (Kd = 7.5 × 10−6 mol L−1) in comparison with alkali and alkaline earth metal ions (K+, Na+, Mg2+, Ca2+) and other transition metal ions (Mn2+, Ni2+, Co2+, Cu2+, Zn2+, Cd2+, Ag+, Pb2+, Cr3+, Fe3+). Meanwhile the distinct color changes and rapid switch-on fluorescence also provide ‘naked eyes’ detection for Hg2+ over a broad pH range. Moreover, such sensor is cell-permeable and can visualize the changes of intracellular mercury ions in living cells using fluorescence microscopy. 相似文献
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A simple, cost-effective yet rapid and sensitive sensor for on-site and real-time Hg2+ detection based on bovine serum albumin functionalized fluorescent gold nanoparticles as novel and environmentally friendly
fluorescent probes was developed. Using this probe, aqueous Hg2+ can be detected at 0.1 nM in a facile way based on fluorescence quenching. This probe was also applied to determine the Hg2+ in the lake samples, and the results demonstrate low interference and high sensitivity. 相似文献
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The chiral polymer was synthesized by the polymerization of 4,7-diethynylbenzo[2,1,3]-thiadiazole (M-1) with (R)-6,6′-dibutyl-3,3′-diiodo-2,2′-bis(diethylaminoethoxy)-1,1′-binaphthyl (R-M-1) via Pd-catalyzed Sonogashira reaction. The chiral polymer has orange fluorescence due to the extended π-electronic structure between binaphthyl unit and benzo[2,1,3]thiadiazole (BT) group via ethynyl bridge. The responsive optical properties of the polymer on various metal ions were investigated by fluorescence spectra. The fluorescence of the chiral polymer can produce the pronounced enhancement as high as 1.8-fold upon addition of 1:2 molar ratio of Hg2+. Compared with other cations, such as K+, Mg2+, Pb2+, Co2+, Ni2+, Ag+, Cd2+, Cu2+, Zn2+, Mn2+ and Fe3+, Hg2+ can produce the pronounced fluorescence response of the polymer. The result indicates this kind of chiral polybinaphthyls incorporating diethylamino and benzo[2,1,3]thiadiazole (BT) moieties as receptors exhibits highly sensitive and selective behavior for Hg2+ detection. 相似文献
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Huili Chen Yanbo Wu Yunfei Cheng Hong Yang Fuyou Li Pin Yang Chunhui Huang 《Inorganic chemistry communications》2007,10(12):1413-1415
Spectroscopic studies revealed that the compound [N,N′-di(quinoline-2-methylene) -1,2-phenylenediimine] (1) exhibited a rather high selectivity toward Zn2+ over other metal ions, even Cd2+. In acetonitrile, the red shift of fluorescent emission from 396 nm to 426 nm upon zinc binding is due to the formation of a 1:1 metal/ligand complex. 相似文献
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Xiangzhi Li Chunling Zheng Ailing Yuan Lu Yang Han Wang Haibo Wang 《Coloration Technology》2014,130(3):236-242
A sulfur probe based on 1,8‐naphthalimide was designed and synthesised, and its sensing behaviour towards a mercury ion was investigated by fluorescence spectroscopy. The probe showed higher selective recognition towards Hg2+ than towards other metal ions in methanol solution. Compared with 4‐amino‐substituted naphthalimide derivatives, the probe exhibited different fluorescent characteristics for sensing Hg2+. The novel, reaction‐based probe is recommended for selective recognition of Hg2+ with significant fluorescence change. 相似文献
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The conjugated polymer P-1 could be synthesized by the polymerization of 4,7-diethynyl-benzo[2,1,3]thiadiazole (M-1) and 1,4-bis[3′-(N,N-diethylamino)-1′-oxapropyl]-2,5-diiodobenzene (M-2) via Pd-catalyzed Sonogashira reaction. The water-soluble conjugated polyelectrolyte P-2 could be obtained by the reaction of P-1 with ethyl bromide. Both P-1 and P-2 can emit orange fluorescence. The responsive optical properties of P-1 and P-2 on Hg2+ were investigated by fluorescence spectra. Hg2+ can lead to nearly complete fluorescence quenching of P-1. On the contrary, Hg2+ can show the most pronounced fluorescence enhancement response of P-2 in aqueous solution without interference from those coexistent ions, such as K+, Mg2+, Pb2+, Co2+, Ni2+, Ag+, Cd2+, Cu2+, Fe3+ and Zn2+. The results also exhibit that this kind of water-soluble conjugated polyelectrolyte can be used as a highly sensitive and selective fluorescence sensor for Hg2+ detection in water. 相似文献
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Mayela De la Cruz-Guzman Angelica Aguilar-Aguilar Luis Hernandez-Adame Alan Ba?uelos-Frias Francisco J Medellín-Rodríguez Gabriela Palestino 《Nanoscale research letters》2014,9(1):431
A rhodamine organosilane derivative (Rh-UTES) has been obtained by one-pot synthesis. The chemical structure of Rh-UTES was confirmed by nuclear magnetic resonance (NMR) and infrared (FTIR) techniques. To obtain an inorganic-organic hybrid sensor, Rh-UTES was covalently immobilized on a porous silicon microcavity (PSiMc) via triethoxysilane groups. The attachment of the organic derivative into PSiMc was confirmed by FTIR, specular reflectance, and scanning electron microscopy (SEM). The optical performance of Rh-UTES receptor for Hg2+ detection was investigated by fluorescent spectroscopy and microscopy. Upon the addition of increasing amounts of Hg2+ ions, a remarkable enhancement in emission intensity was produced in both systems. In the solid phase, an increase of integrated fluorescent emission of 0.12- and 0.15-fold after Hg2+ receptor coordination was observed. The light harvesting capability of PSiMc devices allowed obtaining an enhanced fluorescent emission after Rh-UTES immobilization (277-fold). The fluorescence microscopy of hybrid PSiMc sensor provided an optical qualitative test for Hg2+ detection. 相似文献
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以对氨基酚和3-溴肉桂酸为原料,以4-溴-1,8-萘酰亚胺为荧光母体设计合成了一例用于检测细胞内肼的荧光探针NH1。该探针能够对肼产生特异性响应。利用1H NMR、MS对NH1进行了结构确证。在体外测试中,探针NH1最大发射波长处(λem=535 nm)的荧光强度随着肼含量的增加而逐渐增强,并且具有良好的线性关系(R2=0.99),检测限为0.23 μmol/L。该探针有着良好的选择性和抗干扰能力,在广泛pH范围内(4.5~10.5)均能够特异性检测肼。该探针能够染色到细胞内对细胞内的肼进行检测。 相似文献
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Microgels exhibiting thermochromic behavior based on fluorescence resonance energy transfer (FRET) are prepared. The FRET microgels consist of poly(N‐isopropylacrylamide) (PNiPAm) networks with fixed fluorescein and rhodamine moieties and exhibits volume phase transition (VPT) at 34–35°C. A critical decrease in their sizes during the VPT enhances the efficiency of FRET between fluorescein as a donor and rhodamine as an acceptor. Therefore, emission from fluorescein (523 nm) and that of rhodamine (579 nm) is dominant at temperatures below and above the VPT temperature, respectively, when fluorescein is excited. We also prepare thermochromic core‐shell FRET microgel exhibiting two‐step color change. The microgels consist of a PNiPAm core and a poly(N‐isopropylacrylamide‐co‐N,N‐diethylacrylamide) shell and exhibit dual temperate‐responsiveness at 19 and 33°C. The fluorescence spectrum of the microgels also changes in two steps at these temperatures. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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Guojie Wang Yani Wang Biqing Bao Jie Dong Jian Zhang Lianhui Wang Huai Yang Xiaowei Zhan 《应用聚合物科学杂志》2011,121(6):3541-3546
A new water‐soluble fluorescent conjugated polyelectrolyte, poly[9,9‐bis(3′‐butyrate)fluoren‐2,7‐yl] sodium (BBS‐PF), was studied as a fluorescent probe for protein sensing. The conjugated polyelectrolyte BBS‐PF shows high fluorescence sensitivity to cytochrome c, lysozyme, and bovine serum albumin (BSA). The Stern–Volmer constant (Ksv) in cytochrome c was measured to be as high as 6.1 × 107 L/mol, approximately twice as that of the other two. Interestingly, it is found that BSA slightly enhances the fluorescence of BBS‐PF rather than quenches the fluorescence at its micromolar concentrations. The excitation spectra confirm that the interaction of BBS‐PF with the proteins could be different. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献