A family of neutral fluorescentprobes was developed, mimicking the overall structure of natural glycolipids in order to optimize their membrane affinity. Nonreducing commercially available di- or trisaccharidic structures were connected to a push–pull chromophore based on dicyanoisophorone electron-accepting group, which proved to fluoresce in the red region with a very large Stokes shift. This straightforward
作者:Erin L. Cole、Easwaran Arunkumar、Shuzhang Xiao、Bryan A. Smith、Bradley D. Smith
DOI:10.1039/c2ob06783h
日期:——
Eight fluorescent squaraine rotaxanes with deep-red absorption/emission wavelengths were prepared and assessed for chemical stability and suitability as water-soluble, fluorescent tracers. The most stable squaraine rotaxanes have four large stopper groups attached to the ends of the encapsulated squaraine, and two members of this structural class have promise as highly fluorescent tracers with rapid renal clearance and very low tissue uptake in living mice.
Azo dyes are currently used to quench the fluorescence of energy donors in bioassays through Forster resonance energy transfer (FRET) phenomenon. Common examples of such dark quenchers are DABCYL and the three members of Black Hole Quencher (R) (BHQ) family. Yet, only carboxylic acid and phosphoramidite derivatives of such azo dyes are presently commercially available. This Letter presents a straightforward synthesis method to novel bioconjugatable quenchers derived from BHQ-1 scaffold and equipped with a reactive group being either azido, terminal alkyne, or maleimide. The potential utility of the 'clickable' azido and thiol-reactive derivatives was notably demonstrated through the preparation of the first water-soluble BHQ-1 dye and a FRET-based probe suitable for the detection of urokinase-type plasminogen activator (uPA), a key protease in cancer invasion and metastasis, respectively. (C) 2014 Elsevier Ltd. All rights reserved.
Dye-incorporated water-soluble polymer via click triazole formation
作者:Byungkwon Jang、Sung Yoon Kim、Jung Yun Do
DOI:10.1016/j.dyepig.2012.01.012
日期:2012.8
A click triazole-polymerization is proposed for the synthesis of a water-soluble polymer dye. 4,4'-Diazidostilbene-2,2'-disulfonate (DASS) sodium salt reacted with a diacetylenic derivative of para-methyl red (PMR) in water, which was catalyzed by copper (I) ion or accelerated under ultrasound irradiation. DASS formed a soluble polymer with a carboxylate salt of PMR showing a water solubility of 120 g/100 mL but it generated an insoluble polymer with an alkyl ammonium salt. The prepared polymeric dye underwent color transition at pH 5-6, which is higher than that of PMR and similar to that of ortho-methyl red (OMR). The quinonoid canonical structure of PMR generated a purple water solution and was dominant in the polymer solution at pH below 5. Intra-molecular hydrogen bonding between the triazoles and azo nitrogens was presumed to have induced the formation of the quinonoid structure. The color change of the polymer was reproducible during successive up/down pH cycles. (C) 2012 Elsevier Ltd. All rights reserved.
Efficient Synthesis of Fluorescent Squaraine Rotaxane Dendrimers
作者:Shuzhang Xiao、Na Fu、Kaitlin Peckham、Bradley D. Smith
DOI:10.1021/ol902546m
日期:2010.1.1
A squaraine rotaxane scaffold with four alkyne groups is readily converted into a range of dendritic architectures using high-yielding copper-catalyzed alkyne azide cycloaddition (CuAAC) chemistry. A convergent synthesis approach is more efficient than a divergent pathway. Dendritic squaraine rotaxanes with peripheral amine groups can be further functionalized to produce multivalent deep-red fluorescent derivatives that exhibit high brightness and outstanding chemical stability in biological solution. The surface groups on these functionalized fluorescent dendrimers include guanidinium, mannose, and phosphatidylcholine.