A lucky chance: An unexpectedhalogen effect afforded novel squaraine‐basedbright near‐infrared (NIR) fluorophores with nearly total transparency in the visible region and bright emission in the NIR region beyond 900 nm (see picture).
Current affairs: Acceptor‐substituted squaraines exhibit unprecedented short‐circuit current density of up to 12.6 mA cm−2 in small‐molecule‐based solution‐processed bulk heterojunction (BHJ) solarcells (see picture). These values are closing the gap to polymer solarcells and together with the NIR absorption of the new cells may lead to wide applications.
时事:受体取代的方晶在基于小分子的固溶异质结(BHJ)太阳能电池中表现出前所未有的短路电流密度,高达12.6 mA cm -2(见图)。这些值正在缩小与聚合物太阳能电池的差距,并且与新电池的NIR吸收一起可能会导致广泛的应用。
Selective G-Quadruplex DNA Recognition by a New Class of Designed Cyanines
作者:Rupesh Nanjunda、Eric Owens、Leah Mickelson、Tyler Dost、Ekaterina Stroeva、Hang Huynh、Markus Germann、Maged Henary、W. Wilson
DOI:10.3390/molecules181113588
日期:——
A variety of cyanines provide versatile and sensitive agents acting as DNA stains and sensors and have been structurally modified to bind in the DNA minor groove in a sequence dependent manner. Similarly, we are developing a new set of cyanines that have been designed to achieve highly selective binding to DNA G-quadruplexes with much weaker binding to DNA duplexes. A systematic set of structurally analogous trimethine cyanines has been synthesized and evaluated for quadruplex targeting. The results reveal that elevated quadruplex binding and specificity are highly sensitive to the polymethine chain length, heterocyclic structure and intrinsic charge of the compound. Biophysical experiments show that the compounds display significant selectivity for quadruplex binding with a higher preference for parallel stranded quadruplexes, such as cMYC. NMR studies revealed the primary binding through an end-stacking mode and SPR studies showed the strongest compounds have primary KD values below 100 nM that are nearly 100-fold weaker for duplexes. The high selectivity of these newly designed trimethine cyanines for quadruplexes as well as their ability to discriminate between different quadruplexes are extremely promising features to develop them as novel probes for targeting quadruplexes in vivo.
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 Optical Properties of Near-Infrared meso-Phenyl-Substituted Symmetric Heptamethine Cyanine Dyes
作者:Andrew Levitz、Fahad Marmarchi、Maged Henary
DOI:10.3390/molecules23020226
日期:——
series of 15 meso phenyl-substituted heptamethine cyanines was synthesized utilizing a modified dianil linker. Their opticalproperties, including molar absorptivity, fluorescence, Stokes shift, and quantum yield were measured. The HSA binding affinities of two representative compounds were measured and compared to that of a series of trimethine cyanines previously synthesized by our lab. The results