314270-67-2Relevant articles and documents
Study of the interaction between 2,5-di-[2-(4-hydroxy-phenyl)ethylene]- terephthalonitril and bovine serum albumin by fluorescence spectroscopy
Zhang, Li-Na,Wu, Fang-Ying,Liu, Ai-Hong
, p. 97 - 103 (2011)
A new compound, 2,5-di-[2-(4-hydroxy-phenyl)ethylene]-terephthalonitrile (DHPEPN), was synthesized. The interaction between bovine serum albumin (BSA) and DHPEPN in Tris-HCl buffer solution (pH 7.4) was investigated using fluorescence and UV-vis absorption spectroscopy. The mechanism of BSA fluorescence quenched by DHPEPN is discussed according to the Stern-Volmer equation. The binding constant and the thermodynamic parameters ΔH, ΔS, ΔG at different temperatures were calculated. The results indicate that the van der Waals interaction and hydrogen bonding play major roles in the binding process. The distance between BSA and DHPEPN is estimated to be 3.59 nm based on the Fo?rster resonance energy transfer theory. The spectral changes of synchronous fluorescence and three-dimensional fluorescence suggest that both of the microenvironment of DHPEPN and the conformation of BSA are changed during binding between DHPEPN and BSA.
Synthesis and photophysical studies of back-to-back dinuclear platinum terpyridine complexes with different substituents on the bridging ligand
Liu, Rui,Li, Zhongjing,Zhu, Hongjun,Sun, Wenfang
scheme or table, p. 383 - 389 (2012/07/14)
Four back-to-back dinuclear platinum terpyridine complexes with different substituents on the bridging ligand (1a-1d) were synthesized and characterized. Their electronic absorption, photoluminescence and triplet transient difference absorption were systematically investigated. All complexes exhibit strong 1MLCT/1ILCT absorption bands in the visible region, which significantly red-shifts when electron-donating substituents are introduced on the conjugated bridge and blue-shifts when electron-withdrawing substituents are present. Excitation of 1a and 1d in solution at their respective low-energy absorption band at room temperature results in an orange and red luminescence, respectively, which can be tentatively attributed to the 1MLCT/ 1ILCT excited state. These complexes exhibit intense broad triplet transient difference absorption in the visible to the near-IR region, which likely arises from the ligand-localized states (3π,π* or 3ILCT). Electron-donating substituent causes a pronounced red-shift, while electron-withdrawing substituents induce a blue-shift of the triplet transient absorption bands.
Five orders-of-magnitude enhancement of two-photon absorption for dyes on silver nanoparticle fractal clusters
Wenseleers, Wim,Stellacci, Francesco,Meyer-Friedrichsen, Timo,Mangel, Timo,Bauer, Christina A.,Pond, Stephanie J.K.,Marder, Seth R.,Perry, Joseph W.
, p. 6853 - 6863 (2007/10/03)
Strong enhancement of the two-photon absorption of organic molecules near silver nanoparticle fractal clusters has been observed and has been exploited to yield composite materials with very strong two-photon absorption and two-photon-excited fluorescence properties. Measurements on cluster films coated with chromophoric polymer or with thiol-bound chromophores give spatially-averaged enhancements of 1000 and 20000, respectively. Two-photon fluorescence microscopy studies show that the enhancements are spatially inhomogeneous, with peak-enhancement factors of a?￥ 10000 (polymer/cluster) and a?￥ 160000 (thiol chromophore/cluster), and excitation frequency dependent. These results are in accord with theoretical predictions of local-field effects due to strong localization of collective plasmon modes in fractal metal clusters, and demonstrate an approach to ultrasensitive two-photon processes.
