Photophysical characterization and BSA interaction of the direct ring carboxy functionalized unsymmetrical NIR cyanine dyes
作者:Maryala Saikiran、Daisuke Sato、Shyam S. Pandey、Takeshi Ohta、Shuzi Hayase、Tamaki Kato
DOI:10.1016/j.dyepig.2017.01.015
日期:2017.5
owing to their enhanced dye aggregation. Interaction of these dyes with BSA leads to not only enhanced emission intensity but also bathochromically shifted absorption maximum due to formation of dye-BSA conjugate. These dyes bind strongly with BSA having about an order of magnitude higher binding constant as compared to the typical cyaninedyes. Amongst the unsymmetrical cyaninedyes investigated in this
合成了具有直接-COOH官能化吲哚环的新型近红外(NIR)敏感的不对称花青染料,对其进行了表征和光物理研究。然后,对这些不对称的花青染料进行研究,以研究它们与磷酸盐缓冲溶液中作为模型蛋白的牛血清白蛋白(BSA)的相互作用。除了具有高摩尔消光系数的NIR吸收和发射外,由于其增强的染料聚集作用,它们在PBS溶液中显示出蓝移。这些染料与BSA的相互作用不仅导致发射强度增强,而且由于形成染料-BSA共轭物而导致红移最大吸收。与典型的花青染料相比,这些染料与BSA牢固地结合,其结合常数高约一个数量级。7 M -1。
Synthesis and linear/nonlinear optical properties of a new class of ‘RHS’ NLO chromophore
作者:Andrew J. Kay、Anthony D. Woolhouse、Yuxia Zhao、Koen Clays
DOI:10.1039/b315274j
日期:——
Examples of a new class of zwitterionic, âright-hand sideâ merocyanines containing a cyanodicyanomethylidenedihydrofuran electron acceptor have been prepared. As well as allowing for the facile synthesis of these chromophores, our synthetic methodology enables considerable variation in both the donor moiety as well as the extent of conjugation between the donor and acceptor systems. As expected, all of these âright-hand sideâ systems are negatively solvatochromic, with the difference between λmax
(polar vs. nonpolar solvents) increasing with the extent of conjugation. In accord with expectations, hyper-Raleigh scattering (HRS) measurements confirm that molecules with the greatest conjugation pathway (for e.g.21c, 23c) have the largest first hyperpolarisabilites, βo. In addition, our HRS evaluation indicates that the 4-quinolinylidene donor nucleus is superior to both the 4-pyridinylidene and benzothiazolylidene systems. The figures of merit, μ(calc).βo(measured), that we obtain for some of these compounds, are of a similar magnitude to the best âleft hand sideâ examples reported in the literature. In order to demonstrate the versatility of our synthetic technique, representative polymer-tetherable derivatives of these compounds have been prepared, as have the corresponding TDI-based polyurethanes.
Symmetric anionic polymethine dyes derived from fluorene and its derivatives with electron-acceptor substituents: synthesis and spectral properties
作者:I. V. Kurdyukova、N. A. Derevyanko、A. A. Ishchenko、D. D. Mysyk
DOI:10.1007/s11172-012-0040-7
日期:2012.2
Novel anionic polymethine dyes were synthesized from 2,7-bis(phenoxysulfonyl)-, 2,7-dinitro-, and 2,4,5,7-tetranitrofluorenes. The reasons for the complicated shape of their absorption spectra were analyzed: the formation of contact ion pairs, associates, and conformational isomers and electronic effects of substituents. The quantum chemical calculations by the Pariser—Parr—Pople method and nonempirical
Synthesis and fluorescent characteristics of imidazole–indocyanine green conjugates
作者:Christopher Pavlik、Nrusingh C. Biswal、Faith Corbo Gaenzler、Martha D. Morton、Liisa T. Kuhn、Kevin P. Claffey、Quing Zhu、Michael B. Smith
DOI:10.1016/j.dyepig.2010.08.008
日期:2011.4
We have successfully synthesized imidazole-dye conjugates by linking imidazole and nitroimidazoleacetic acids to an indocyanine green (ICG) carboxylic acid derivative using an ethanolamine linker These dye-conjugates show absorbance peaks at 754-756 nm and fluorescence peaks at 780 rim The dye-conjugates show a blue shift of 25 nm and 30 nm in the absorption and fluorescence spectra respectively when compared to that of standard cardiogreen There is no change in absorption and fluorescence spectral profiles between the ICG derivative and imidazole conjugates The extinction coefficients of new ICG derivative and imidazole conjugates are 1 8 times higher than that of standard ICG The relative quantum yields of the new compounds are 4 5-5 5 times higher than that of the Sigma-Aldrich s ICG The dyes are tested for hypoxia in-vitro with 4T1 luc cell lines and it is found that the cells treated with 2-nitroimidazole ICG show a contrast of fluorescence signal of 2 5-30 for the cells under hypoxic to that of cells under normoxic However pure ICG shows no significant difference between hypoxic and normoxic cells (C) 2010 Elsevier Ltd All rights reserved