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11.
In the presented work studies of the interaction mode of monomer and two homodimer benzothiazole styryl dyes containing spermine-like
linkage/tail group with the double stranded (ds) DNA are reported. For these dyes, equilibrium constant of dye binding to
DNA (K
b), as well as the number of dsDNA base pairs occupied by one bound dye molecule (n) were determined. The data obtained show that the presence of spermine-like group containing quaternary nitrogen (Bos-5)
results in increase of K
b value as compared to this of unsubstituted analogue (Sbt). Besides, for the dimer dyes containing benzothiazole styryl chromophores,
the K
b value is either five times higher (DBos-13) or almost the same (DBsu-10) as compared to this of corresponding monomer Sbt,
depending on the position in the benzothiazole ring where the linker is attached. Moreover, the n values for both dimers are significantly different as well, pointing to the bis-intercalative binding mechanism for DBos-13
and for the groove-binding one for DBsu-10. The conclusion about the dimer dyes-dsDNA binding mechanisms is also supported
by the study of the fluorescent response of these dyes on the presence of AT- and GC-containing polynucleotides. 相似文献
12.
Losytskyy MY Volkova KD Kovalska VB Makovenko IE Slominskii YL Tolmachev OI Yarmoluk SM 《Journal of fluorescence》2005,15(6):849-857
A series of pentamethine cyanine dyes with cyclohexene or cyclopentene group in polymethyne chain, assumed as DNA groove-binders,
were studied as fluorescent probes for nucleic acids as well as for native and denatured proteins. It was revealed that the
presence of methyl or dimethyl substituent in 5 position of the cyclohexene group hinders the formation of dye–DNA fluorescent
complex, while the methyl substituent in 2 position leads to the increasing of the dye–DNA complex fluorescence intensity.
The dyes SL-251, SL-1041, and SL-1046 containing methyl group in the 2 position of the cyclic group, are reported as bright
DNA-sensitive dyes. The study of the dyes DNA-binding specificity demonstrated significant AT-preference that points to the
groove-binding interaction mode. At the same time, the dyes SL-251, SL-377, and SL-957 with the 2-methyl substituted cyclohexene
group were shown to be sensitive fluorescent dyes both for nonspecific (in SDS presence) proteins detection and for native
BSA. 相似文献
13.
Valentyna P. Tokar Mykhaylo Yu. Losytskyy Tymish Y. Ohulchanskyy Dmytro V. Kryvorotenko Vladyslava B. Kovalska Anatoliy O. Balanda Igor M. Dmytruk Vadym M. Prokopets Sergiy M. Yarmoluk Valeriy M. Yashchuk 《Journal of fluorescence》2010,20(4):865-872
Spectral-fluorescent properties of benzothiazole styryl monomer (Bos-3) and homodimer (DBos-21) dyes in presence of DNA were
studied. The dyes enhance their fluorescence intensity in 2–3 orders of magnitude upon interaction with DNA. Studied styrylcyanines
in DNA presence demonstrate rather high values of two-photon absorption (TPA) cross-section, which are comparable with the
values of TPA cross section of the rhodamine dyes. An applicability of the styrylcyanines as probes for the fluorescence microscopy
of living cells was studied. It was shown that both dyes are cell-permeable but homodimer dye DBos-21 produces noticeably
brighter staining of HeLa cells comparing with monomer dye Bos-3. Molecules of DBos-21 initially bind to the nucleic acids-
containing cell organelles (presumable mitochondria) and are able to penetrate into the cell nucleus. Thus, homodimer styryl
DBos-21 dye is viewed as efficient stain for single-photon and two-photon excitation fluorescence imaging of living cells. 相似文献
14.
Fluorescence of Styryl Dyes-DNA Complexes Induced by Single- and Two-Photon Excitation 总被引:1,自引:1,他引:0
Tokar VP Losytskyy MY Kovalska VB Kryvorotenko DV Balanda AO Prokopets VM Galak MP Dmytruk IM Yashchuk VM Yarmoluk SM 《Journal of fluorescence》2006,16(6):783-791
The series of novel monomer and homodimer styryl dyes based on (p-dimethylaminostyryl) benzothiazolium residues were synthesized and studied as possible fluorescent probes for nucleic acids
detection. Spectral-luminescent and spectral-photometric properties of obtained dyes in the unbound state and in DNA presence
were studied. Fluorescence emission induced by two-photon excitation of dye-DNA complexes in aqueous buffer solution was registered.
Two-photon absorption cross section values of the studied dyes in DNA presence were evaluated. 相似文献
15.
Kostenko OM Kovalska VB Volkova KD Shaytanov P Kocheshev IO Slominskiy YL Pisareva IV Yarmoluk SM 《Journal of fluorescence》2006,16(4):589-593
Fluorescent chromophore, alkylamino-(tetra-hydronaphthalenylidene)- benzothiazolium derivatives (HBTN dyes), are proposed as covalent labels for proteins via aliphatic amino groups. Spectral-luminescent properties of 3-methyl-2-{(E)-[7-(methylamino)-4,4a,5,6-tetra-hydronaphthalen-2(3H)-ylidene]methyl}-1,3-benzothiazol-3-ium chloride (HBTN, R=Me) and its predecessor, 2-[(E)-(7-methoxy-4,4a,5,6-tetrahydronaphthalen-2(3H)-ylidene)methyl]-3-methyl-1,3-benzothia-zol-3-ium chloride (ABTN), are studied for free dyes and in the presence of DNA and BSA. Considerable spectral-luminescent changes accompany the transformation of ABTN into HBTN that allows monitoring conjugation reaction. In presence of DNA and BSA the HBTN increases its emission in 15 and 4 times respectively and becomes strongly fluorescent. The conditions for labeling are developed and a model conjugate of HBTN dye with BSA is synthesized. It was shown that using of HBTN dye as a fluorescent label allows detection by eye of about 3 μg/band of BSA on polyacrylamide gel upon UV-irradiation. 相似文献
16.
Kovalska VB Losytskyy MY Yarmoluk SM 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(1-2):129-136
The series of symmetrical beta-substituted and alpha,gamma-substituted trimethinecyanine dyes were studied for their absorption and fluorescent characteristics in unbound state and in the presence of nucleic acids and proteins. It was shown that beta-substituted and alpha,gamma-bridged trimethinecyanines containing extended heterocyclic systems or N-phenyl as well as N-cyclohexyl substituents demonstrate increased affinity to proteins. At the same time the presence of both N-phenyl and N-cyclohexyl substituents leads to the decrease of the dye fluorescence intensity in complexes with nucleic acids. For trimethinecyanines similarly to unsymmetrical monomethines the presence of N-omega-hydroxy alkyl substituents results in the increase of fluorescence intensity of dye-DNA complex and the emission decrease of dye-RNA complex. 相似文献
17.
Mykhaylo Y. Losytskyy Vladyslava B. Kovalska Oleg A. Varzatskii Alexander M. Sergeev Sergiy M. Yarmoluk Yan Z. Voloshin 《Journal of fluorescence》2013,23(5):889-895
Interaction of the iron(II) mono- and bis-clathrochelates with bovine serum albumin (BSA), β-lactoglobulin, lysozyme and insulin was studied by the steady-state and time-resolved fluorescent spectroscopies. These cage complexes do not make significant impact on fluorescent properties of β-lactoglobulin, lysozyme and insulin. At the same time, the monoclathrochelates strongly quench a fluorescence intensity of BSA and substantially decrease its excited state lifetime due to their binding to this protein. This occurs due to the excitation energy transfer from a tryptophan residue to a cage molecule or/and to the change of the tryptophan nearest environment caused by either clathrochelate binding or an alteration of the BSA conformation. The effect of the iron(II) bis-clathrochelate on BSA fluorescence is much weaker as compared to its monomacrobicyclic analogs as a result of an increase in its size. 相似文献
18.
A simple method to generate an effective electron-ion interaction pseudopotential from the energy wave number characteristic
obtained by first principles calculations has been suggested. This effective potential has been used, in third order perturbation,
to study the effect of three-body forces on the lattice dynamics of noble metals. It is found that three-body forces, in these
metals, do play an important role. The inclusion of such three-body forces appreciably improves the agreement between the
experimental and theoretical phonon dispersion curves. 相似文献
19.
Bing Wu Dr. Evgeniya Kovalska Dr. Jan Luxa Petr Marvan Štěpán Cintl Prof. Zdenek Sofer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(36):8162-8169
Few-layered black phosphorus (BP) is a two-dimensional material that has attracted intensive attention for applications in energy storage and catalysis due to its large surface area and good electrical and thermal conductivity. Herein, a comparable study of BP electrochemical exfoliation in various solutions of tetrabutylammonium salts (TBAX; X is PF6−, BF4−, and ClO4−) in DMSO is reported. Based on morphological and structural analyses, it is shown that TBAPF6/DMSO medium was specifically appropriate for the production of high-quality BP nanosheets with micrometer lateral size and a thickness of about 2.4 nm. TBAPF6/DMSO-processed, few-layered BP exhibits enhanced hydrogen evolution reaction (HER) catalytic activity compared with that of samples exfoliated with the assistance of BF4− and ClO4− ions. Finally, the fabrication of flexible, free-standing BP films and their performance in an all-solid-state supercapacitor device are demonstrated. 相似文献
20.
Spectroscopic Studies of α,γ-Disubstituted Trimethine Cyanine: New Fluorescent Dye for Nucleic Acids
I. V. Valyukh V. B. Kovalska Y. L. Slominskii S. M. Yarmoluk 《Journal of fluorescence》2002,12(1):105-107
Spectral properties of 3-methyl-2-3-[3-methyl-1,3-benzothiazolo-2(3H)-ylidene]-1,4-cylopentadien-1-yl-1,3-benzothiazolo-3-ium tosylate (Cyan-Cpentd) in a free state and in the complexes with nucleic acids and synthetic polynucleotides have been investigated by absorption and fluorescence spectroscopy. Significant fluorescence intensity enhancement of dye-nucleic acids complexes is observed. For the first time Cyan-Cpentd is proposed as a new probe for nucleic acid detection. Binding mechanism of Cyan-Cpentd is discussed in view of the NA-ligand interaction models. 相似文献