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1.
The near-infrared window of fluorescent heptamethine cyanine dyes greatly facilitates biological imaging because there is deep penetration of the light and negligible background fluorescence. However, dye instability, aggregation, and poor pharmacokinetics are current drawbacks that limit performance and the scope of possible applications. All these limitations are simultaneously overcome with a new molecular design strategy that produces a charge balanced and sterically shielded fluorochrome. The key design feature is a meso-aryl group that simultaneously projects two shielding arms directly over each face of a linear heptamethine polyene. Cell and mouse imaging experiments compared a shielded heptamethine cyanine dye (and several peptide and antibody bioconjugates) to benchmark heptamethine dyes and found that the shielded systems possess an unsurpassed combination of photophysical, physiochemical, and biodistribution properties that greatly enhance bioimaging performance.  相似文献   

2.
In this communication, the synthesis of three unknown polyfluorinated cyanine dyes and their application as selective markers for mitochondria are presented. By incorporating fluorous side chains into cyanine dyes, their remarkable photophysical properties were enhanced. To investigate their biological application, several different cell lines were incubated with the synthesized cyanine dyes. It was discovered that the presented dyes can be utilized for selective near-infrared-light (NIR) staining of mitochondria, with very low cytotoxicity determined by MTT assay. This is the first time that polyfluorinated cyanine fluorophores are presented as selective markers for mitochondria. Due to the versatile applications of polyfluorinated fluorophores in bioimaging and materials science, it is expected that the presented fluorophores will be stimulating for the scientific community.  相似文献   

3.
Asanimportantclassoffunctionalmaterials,squaryliumcyaninedyespossessmanyexcellentpropertiessuchasstablestructures,outstandingphotoconductivityaswellassmallthermalconductivity,andexhibitintenseandsharpabsorptionbandsinthevisibleandnearinfraredregionwithhighlightharvestingcapacity,whichopenupextensiveapplicationsinthevariousfieldsl-3.Inthispaper,twosymmetricalsquaryliumindocyanineswiththeintroductionofhydroxyethylandsulfopropylgroupsontheheterocyclicnitrogenweresynthesizedandcharacterizedbyUV,I…  相似文献   

4.
Calix[4]arene derivatives bearing one or two hydroxystyryl cyanine chromophores at the wide rim of the macrocycle have been synthesized. The influence of bases and Li+ on the UV–Vis spectra of the compounds obtained has been investigated.  相似文献   

5.
NIRer there : Pyrrolopyrrole cyanine (PPCys) dyes, a new class of near‐infrared (NIR) fluorophores, are obtained by condensation of heteroarylacetonitrile and diketopyrrolopyrrole compounds (see picture). Complexation with BF2 or BPh2 yields strongly fluorescent, photostable NIR dyes that show high absorption cross‐sections and fluorescence quantum yields. Furthermore, alteration of the heterocycle can tune the main absorption between λ = 684 and 864 nm.

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6.
The structure of the studied compounds was confirmed by elemental analysis, IR and NMR. TG and DTG data were used to study the kinetics of the thermal decomposition process of some new cyanine dispersed dyes derived from 2-[(p-chloro)-styryl]-6-[5-(3-aryl-rhodanine)]-1,2-dihydropyridine. The reaction was found to follow first order mechanism. The activation energy Ea was calculated and used to calculate the thermodynamic parameters enthalpy change (H*), entropy change (S*), and free energy change (G*), related to the thermal decomposition process. Two different calculation methods including Coats—Redfern and Chatterjee were applied to evaluate thekinetic and thermodynamic parameters. Quantum study was performed to support both the structure and the thermal data.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

7.
Treatment of dye 3 with sodium methoxide, morpholine, or diphenylphosphine gives the respective substituted derivatives 4, 5 and 6 in high yields. The reaction of 3 with sodium acetate followed by workup affords ketone 7 which is also obtained by demethylation of a methoxy derivative 4 under non-hydrolytic conditions.  相似文献   

8.
本文就冠醚菁染料及其重要中间体的合戍方法、冠醚菁染料的络合性能、光热稳定性和光谱增感性能的研究进行了系统的介绍与评述,同时反映了国内外有关冠醚化合物在感光材料中的应月以及冠醚菁染料在其他领域中的最新研究成果,显示了它们潜在的应用前景。  相似文献   

9.
10.
菁染料是一类经典的荧光染料母核, 具有摩尔消光系数大、 吸收波长可调、 溶解性良好及生物兼容性好等优点, 被广泛用于蛋白标记、 痕量金属离子检测、 生物活性物质检测、 细胞和活体成像及肿瘤靶向治疗等领域. 近年来, 生物医学领域对活体结构及功能成像深度提出更高的需求, 基于优异的长波长染料母核开发近红外荧光分子探针逐渐成为领域的研究重点. 吲哚七甲川菁染料(Cy7)是一类最具代表性的菁染料, 本文重点综合评述了自1992年以来基于Cy7结构开发的分子探针, 并介绍了该类荧光探针的设计策略. 最后, 讨论了该领域研究面临的挑战, 并对未来的发展方向进行了总结和展望.  相似文献   

11.
12.
Near-infrared (NIR) dyes are sought after for their utility in light harvesting, bioimaging, and light-mediated therapies. Since long-wavelength photoluminescence typically involves extensive π-conjugated systems of double bonds and aromatic rings, it is often assumed that NIR dyes have to be large molecules that require complex syntheses. We challenge this assumption by demonstrating that facile incorporation of tertiary amine groups into readily available 3-cyanoformazans affords efficient production of relatively simple NIR-active BF2 formazanate dyes (λabs=691–760 nm, λPL=834–904 nm in toluene). Cyclic voltammetry experiments on these compounds reveal multiple reversible redox waves linked to the interplay between the tertiary amine and BF2 formazanate moieties. Density-functional calculations indicate that the NIR electronic transitions in BF2 formazanates are of π→π*-type, but do not always involve strong charge transfer.  相似文献   

13.
本文首次报道冠醚菁染料3,3’-二乙基-5,6,5’,6’-双骈-(15-冠-5)-硫碳菁碘盐(1)和3,3’-二乙甲基-5,6-骈-(15-冠-5)-硫碳菁碘盐(2)以及合成中间体:4’-溴5’-硝基-苯骈-15-冠-5(3),2.2’-二硝基-4,5,4’,5’-双骈-(15-冠-5)-二本基二硫化物(4),2-甲基-5,6-骈-(15-冠-5)-苯骈噻唑(5)和2-甲基-3-乙基-5,6-骈-(15-冠-5)-苯骄噻唑碘盐(6)的特征红外光谱图。  相似文献   

14.
七甲川花菁染料的研究进展   总被引:7,自引:0,他引:7  
俞开潮  金玲  程红 《合成化学》2004,12(1):38-42,68
近红外七甲川花菁染料作为功能染料不断得到广泛应用。本文主要对七甲川花菁染料的结构、合成及其应用进行了综述。参考文献23篇。  相似文献   

15.
Based on the analysis of UV/Vis-and CD spectra of several cyanine dyes in - and -cyclodextrin a case is made for the aggregation of the dyes into oligomers. The criteria for this new type of aggregates are: (i) the appearance of a concentration and temperature dependent shoulder on the high energy side of the dimer band in the UV/Vis-spectra; (ii) two oppositely signed high intensity CD absorptions, one centered at the shoulder, the other at about the energy of the monomer absorption. Calculations based on coupled-oscillator theory support the contention that chiral dye aggregates are formed in the presence of cyclodextrins, most probably trimers and tetramers. From UV/Vis- and CD-data a helically twisted sandwich structure is suggested for these aggregates. In contrast to the reported inclusion complexes these aggregates must form — at least partly — outside the chiral host.  相似文献   

16.
菁染料的研究已有一百多年的历史,其最重要的用途是作为光谱增感剂应用于卤化银照相乳剂中,扩大卤化银微粒的感光范围并提高感光度[1].近年来又开展了在其它领域的应用研究,发现它的许多特殊用途。  相似文献   

17.
以苯并碲唑季铵碘盐为原料,将其与3-乙基-2-(β-乙酰苯胺)乙烯工噻唑磺化季铵盐在无水吡啶中回流,得到4个含碲不对称碳菁染料,上述季铵盐与方酸的反应不 般杂环碱,只能发生1:1缩合反应,缩合产物与苯并噻唑碘盐在正丁醇/吡啶中反应即得含碲不对称方酸菁染料,该法避免了通常制备不对称方酸菁所带来的分离纯化的困难,从而提供了制备不对称方酸碲菁染料的通用方法,研究了不对称碲碳菁的“Brooker偏差”,结  相似文献   

18.
Photoelectric characteristics were measured for photorefractive aromatic polyimides containing nanocrystalline J-aggregates of thiacarbocyanine dyes, which are responsible for the photoelectric sensitivity at the Ar–Kr laser emission wavelength of 647 nm. The amplitude and the speed of writing of the photorefractive diffraction grating were determined by the stationary value of the ratio (j ph + j d)/j d and by the rate of the growth of photocurrent j ph to the stationary value, respectively. The dependence of the quantum yield of free charge carriers on the applied electric field was linear in the vs. (E 0)3.5 coordinates. Experimental results fitted well to the curve calculated up to (E 0)4 according to the Onsager equation with the initial quantum yield of the bound electron–hole pairs assumed to be 0 = 0.2 and the charge separation distance in the pair of r 0 = 12 Å.  相似文献   

19.
Here, the synthesis of two novel series of dichromophoric cyanine dyes were reported. The first series of novel bis-azacyanine dyes 3a–d was afforded by reaction of 2-(1,3,3-trimethyle indoline-2-ylidene)acetaldehyde with diaminoaromatics, and the second series of novel bis-diazacyanine dyes 4a–d was obtained using quaternization of an amine group in disazo compounds, which were produced by the reaction of disazoaromatics with 2-methylene-1,3,3-trimethyle indoline. The products were identified by 1H NMR, 13C NMR, infrared, UV-vis, and mass spectroscopy.  相似文献   

20.
采用飞秒荧光上转换技术,研究了阴阳离子菁染料及对应的阴离子和阳离子菁染料吸附在立方型和T型溴碘化银表面上形成J-聚集体的荧光衰减时间分辨特性,分析了几种菁染料增感体系的超快电子转移动力学过程及其对增感效率的影响.通过比较几种菁染料增感体系的荧光衰减特性,两种阴阳离子染料要明显快于阴离子染料、阳离子染料及二者的加合,说明阴阳离子染料聚集体到溴碘化银的电子注入速率较快,增感效果更好.对两种阴阳离子染料聚集体荧光衰减特性的比较,可以看出染料在T型颗粒溴碘化银上形成聚集体的荧光寿命更短,因而对T型颗粒的增感效果更好.染料Dye2的荧光衰减要快于染料Dye1,说明染料Dye2到溴碘化银的电子注入速率更快,增感效率更高.  相似文献   

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