一种基于次氯酸根离子的比率型荧光探针及其应用

以2-苯并噻唑-5-甲基苯酚为原料,合成了一种基于次氯酸根离子的比率型荧光探针ZN1,并对其进行了次氯酸根离子的检测性能测试。结果表明:该探针可以快速灵敏、选择性地识别次氯酸根离子,其检测下限为0.96μmol/L,并将该探针应用于实际水样中次氯酸根离子含量的检测,在自来水、雨水中的回收率均大于84%。此外,利用质谱和核磁谱图开展的检测机理研究表明,探针的识别机理与次氯酸的氧化脱氢作用和激发态分子内质子转移(ESIPT)过程破坏有关。     

一种新型比率型次氯酸根荧光探针的合成及性能研究

以4-二苯氨基苯甲醛为原料,与水合肼进行缩合反应,设计合成一种识别0C1_的比率型荧光探针.通过光谱分析,加入oCl-,荧光发射强度明显升高,溶液颜色由黄色变为无色,实现裸眼识别;加入其他分析物,荧光强度无明显变化.在0.5～1 μmol/L的浓度范围内,荧光强度与次氯酸根浓度呈良好的线性关系,最低检出限为0.44pm...     

用于溶酶体定位的比率型次氯酸根探针的构建及应用研究

以常见荧光团罗丹明和萘酰亚胺设计并合成了一例用于比率型识别次氯酸根的荧光探针。结果表明,探针能够对次氯酸根实现高效专一的比率型选择,能够克服其他分析物的干扰。溶液体系荧光发射强度比率值(F_(590 nm)/F_(542 nm))在次氯酸钠浓度为0～1μmol/L范围内呈现良好的线性,其对次氯酸根的最低检出限为1.3×10~(-8) mol/L。探针可以定位于亚细胞器溶酶体中识别次氯酸根,并且能够应用于自来水等实际样品中检测次氯酸根。     

比率型锌离子荧光探针的研究进展

比率型荧光探针通过内标的建立,扩大了荧光探针动态响应的范围,具有双波长发射、背景干扰小及可定量检测等优点,近年来,被广泛用于生命相关金属离子的定量检测。综述了近十年来比率型锌离子荧光探针的设计及成像应用,并展望了其在体内环境下锌离子的定量检测前景和发展方向。     

激发态分子内质子转移荧光探针的研究进展

综述了基于激发态分子内质子转移(ESIPT)荧光探针的相关研究,并对ESIPT机理和ESIPT荧光团的2-(2'-羟苯基)苯并杂环类(咪唑、(噁)唑、噻唑)及其衍生物等的主要结构进行了系统介绍.重点介绍了双发光机制荧光探针在检测方面的应用进展.     

用于检测次氯酸的线粒体靶向荧光探针研究进展

次氯酸是一种来源于线粒体的活性氧，在各种生理和病理过程中起着重要的作用。但是，当细胞中的HOCl浓度超过正常值时范围，它会导致机体损伤和一系列疾病。因此，近年来开发设计了一系列能实时识别和监测线粒体中的次氯酸水平的荧光探针，这有助于更好地了解生物体健康状况和HOCl起到的生理作用和病理过程。主要介绍了近几年HOCl荧光探针的应用和发展，根据靶向线粒的基团类别，分别介绍了三苯基膦类荧光探针，半花菁类荧光探针，氟硼吡咯类荧光探针。     

一种新型的用于单线态氧检测的比率型荧光探针

单线态氧(¹O₂)是一种重要的高活性氧分子,在生理学和病理过程中起着关键作用。本文构建了¹O₂ 响应的基于光诱导电子转移(PET)机理的比率型荧光探针Com-Nap。该探针以扩环香豆素和萘酰亚胺衍生物为荧光团,以蒽和扩环香豆素为识别基团,同时以蒽作为萘酰亚胺荧光团的猝灭基团。单独的探针仅表现出扩环香豆素的荧光信号。当¹O₂与探针反应后,PET过程被禁阻,呈现出比率型响应信号。该探针实现了对¹O₂的准确、快速及高选择性检测。     

比率荧光探针的构建及应用

比率荧光法是通过测量两个不同波长处的荧光强度比值作为信号参量,以此来测定目标物的一种分析方法。由于所测得的荧光比值信号不受光源的强度和仪器灵敏度的影响,因此比率荧光探针具有较高的灵敏度、选择性和线性范围。文章中总结了基于有机荧光探针、纳米荧光探针、复合探针等几种荧光比率探针的构建模式,并对其在金属离子和有机物等典型分析物中的应用进行了综述。     

一种基于ESIPT原理的反应型半胱氨酸荧光探针的合成及细胞成像研究

本研究基于分子内质子转移机制(ESIPT),制备了一种具有选择性识别Cys的反应型荧光探针(探针1)。在乙腈-磷酸盐缓冲溶液(3:7,体积比,pH 7.4)中,探针1的荧光强度与Cys的浓度在10～100μmol/L范围内呈现良好的线性关系(y=4.127x+42.84, R²=0.9978),检测限为36.7 nmol/L。该探针对Cys的响应具有较大的Stokes位移(160 nm)、高灵敏度和选择性。此外,探针1还具有良好的细胞膜通透性和生物相容性,可用于A549细胞中Cys的荧光成像,在生物分析中具有潜在的应用价值。     

一种检测环境样品和细胞中肼的香豆素类比率型荧光探针

以香豆素为荧光团,4-溴丁酰基为识别基团,设计合成了一种比率型肼荧光探针COCB。其结构通过1HNMR、13CNMR和HRMS确证。肼对探针COCB中溴代丁酰基的选择性脱保护使分子内电荷转移(ICT)过程恢复；COCB在 420 nm 处蓝色荧光衰减,而在 480 nm 处青色荧光增强,实现了对肼的比率检测。COCB对肼表现出高选择性、高灵敏度和强抗干扰能力,并能在较宽的线性范围(0~250 μmol/L)和pH范围(6~11)内检测肼,检出限低至0.15μmol/L。此外,COCB合成简便,细胞毒性较低,已成功用于实际水样、土壤以及活细胞中肼的检测。     

Theoretical Investigation on the ESIPT Process and Detection Mechanism for Dual-Proton Type Fluorescent Probe

Recently, a new fluorescent probe AE-Phoswas reported to detect the activity of alkaline phosphatases (ALP) in different living cell lines. Here, we present an in-depth computational analysis of the mechanism and source of the fluorescence of the AE-Phos probe. There is an intermediate product (AE-OH-Phos) in the experiment as well as a different configuration of products that may emit fluorescence. It is essential to investigate the origin of fluorescence and the detection mechanism of the probe, which could help us eliminate the interference of other substances (including an intermediate product and possible isomers) on fluorescence during the experiment. According to the change of geometric parameters and Infrared spectra, we deduce that the dual intramolecular hydrogen bonds of salicylaldehyde azine (SA) were enhanced at the excited state, while AE-OH-Phos was attenuated. Considering the complex ESIPT behavior of the dual proton-type probe, the potential energy surfaces were further discussed. It can be concluded that the single proton transfer structure of SA (SA-SPT) is the most stable form. Both the concerted double proton transfer process and stepwise single proton transfer process of SA were forbidden. The fluorescence for SA was 438 nm, while that of SA-SPT was 521 nm, which agrees with the experimentally measured fluorescence wavelength (536 nm). The conclusion that single proton transfer occurs in SA is once again verified. In addition, the distribution of electron-hole and relative index was analyzed to investigate the intrinsic mechanism for the fluorescence quenching of the probe and the intermediate product. The identification of the origin of fluorescence sheds light on the design and use of dual-proton type fluorescent probes in the future.     

水溶性萘酰亚胺氢离子荧光分子探针的合成及性能

4 溴 1,8 萘酐与羟乙氧基乙胺反应合成了中间体N 羟乙氧基乙基 4 溴 1,8 萘酰亚胺。用该中间体分别与哌嗪、甲基哌嗪和羟乙基哌嗪反应 ,合成了 4 哌嗪基、4 (甲基哌嗪 )基和 4 (羟乙基哌嗪 )基 1,8 萘酰亚胺衍生物 (NP - 1、NP - 2和NP - 3)。这 3种化合物具有较好的水溶性 ,其水溶液的荧光强度随溶液由碱性到酸性变化 ,荧光强度增加在 5 0倍以上。NP - 1、NP - 2和NP - 3的pK′a值分别为 8 5、7 6和 6 7。     

Fast-Response Fluorogenic Probe for Visualizing Hypochlorite in Living Cells and in Zebrafish

A fast-response fluorogenic probe—compound D1 —for monitoring hypochlorite (ClO⁻), based on specific ClO⁻ cleavage of a C=N bond and producing results observable to the naked eye, has been developed. The response of the probe to ClO⁻ increases linearly, and the fluorescence intensity was heightened by a factor of about 25. D1 responses to ClO⁻, with high selectivity and sensitivity, were observable by naked eye within 10 s. D1 can not only detect levels of hypochlorite in vitro, such as in urine, but is also capable of monitoring hypochlorite content under extremely cold conditions, as low as −78 °C. Meanwhile, its good biocompatibility permitted the use of D1 to detect intracellular ClO⁻ by confocal microscopy. Moreover, D1 was successfully applied to monitor exogenous and endogenous ClO⁻ in zebrafish through fluorescence imaging.     

A Novel Fluorescent Probe for Retaining Galactosyltransferases

Glycosyltransferases (GTs) are a large class of carbohydrate‐active enzymes that are involved, in both pro‐ and eukaryotic organisms, in numerous important biological processes, from cellular adhesion to carcinogenesis. GTs have enormous potential as molecular targets for chemical biology and drug discovery. For the full realisation of this potential, operationally simple and generally applicable GT bioassays, especially for inhibitor screening, are indispensable tools. In order to facilitate the development of GT high‐throughput screening assays for the identification of GT inhibitors, we have developed novel, fluorescent derivatives of UDP‐galactose (UDP‐Gal) that are recognised as donor analogues by several different retaining galactosyltransferases (GalTs). We demonstrate for one of these derivatives that fluorescence emission is quenched upon specific binding to individual GalTs, and that this effect can be used as the read‐out in ligand‐displacement experiments. The novel fluorophore acts as an excellent sensor for several different enzymes and is suitable for the development of a new type of GalT bioassay, whose modular nature and operational simplicity will significantly facilitate inhibitor screening. Importantly, the structural differences between the natural donor UDP‐Gal and the new fluorescent derivatives are minimal, and the general assay principle described herein may therefore also be applicable to other GalTs and/or proteins that use nucleotides or nucleotide conjugates as their cofactor.     

一种新型Co~(2+)荧光探针的合成及其性能研究

以8-羟基喹啉衍生物与2,4-二羟基苯甲醛为原料,合成了一种新型的离子荧光探针HQHD。该化合物结构通过红外、氢谱、碳谱以及高分辨质谱进行确认。当以V(乙腈)∶V(水)=1∶9缓冲溶液为溶剂时,荧光探针的性能研究表明,在16种常见金属离子和NH~+_4中,HQHD对Co~(2+)具有较好的专一识别能力,p H在6.98~8.6范围内对Co~(2+)的识别能力最强。当Co~(2+)与其他离子形成共存离子溶液时,并不影响HQHD对Co~(2+)的检测效果,说明配体HQHD具有较强的抗干扰能力。当Co~(2+)在0.5×10~(-5)~5×10~(-5)mol/L的浓度范围内,体系的荧光强度ΔF与Co~(2+)的浓度呈现良好的线性关系,线性拟合系数为0.982 6,检测限为9.77×10~(-8)mol/L。Job's plot曲线表明,Co~(2+)与配体比为1∶1。     

新型香豆素类Hg^2+荧光探针的合成及性能研究

以4-二乙胺基水杨醛、三氟乙酰乙酸乙酯以及2-噻吩甲酰肼为原料合成了新型含氟香豆素类硫代酰腙型荧光探针化合物,经1HNMR、13CNMR、19FNMR、HR-MS对化合物结构进行了确认。通过荧光光谱法研究了化合物在乙腈溶液中对金属离子的识别性能。在pH 4.5~9.5的范围内,Hg^2+的加入使得化合物在464 nm处的荧光发射峰发生猝灭,其他金属离子的存在未对该现象造成明显干扰。Hg^2+浓度越高,猝灭效果越明显。因此,化合物对Hg^2+具有良好的荧光选择性和抗干扰性。Job′s曲线表明,化合物与Hg^2+的配合比为1∶1。     

分子内电荷转移荧光传感器的研究进展

荧光传感器提供了方便,快捷,廉价的分析检测重金属离子的方法,并且有很高的灵敏度和选择性.它在环境科学,分析化学以及生命科学等领域有着广泛的应用前景.综述了分子内电荷转移(intramolecular charge transfer)荧光传感器的最新研究进展,并展望了该领域的发展趋势.     

A FRET-Based Near-Infrared Fluorescent Probe for Ratiometric Detection of Cysteine in Mitochondria

We report a near-infrared fluorescent probe A for the ratiometric detection of cysteine based on FRET from a coumarin donor to a near-infrared rhodamine acceptor. Upon addition of cysteine, the coumarin fluorescence increased dramatically up to 18-fold and the fluorescence of the rhodamine acceptor decreased moderately by 45 % under excitation of the coumarin unit. Probe A has been used to detect cysteine concentration changes in live cells ratiometrically and to visualize fluctuations in cysteine concentrations induced by oxidation stress through treatment with hydrogen peroxide or lipopolysaccharide (LPS). Finally, probe A was successfully applied for the in vivo imaging of Drosophila melanogaster larvae to measure cysteine concentration changes.