The interaction between propranolol (PROP) and human serum albumin (HSA) was studied in the presence of dimethyl methylphosphonate (DMMP). DMMP is usually considered as a simulant for chemical warfare agents (CWAs). For this purpose fluorescence quenching, resonance light scattering (RLS), synchronous, three-dimensional fluorescence spectroscopy and molecular dynamics (MD) simulation were emplo...

The effect of three aromatic amines namely aniline (AN), dimethyl aniline (DMAN) and diethyl aniline (DEAN) on emission properties of a coumarin derivative 6-methyl-3azidoacetyl coumarin (6M3AAC) in acetonitrile was studied by means of steady state fluorescence spectroscopy. The quenching of fluorescence intensity was observed in the presence of amines. The quenching process was characterized b...

The effect of three aromatic amines namely aniline (AN), dimethyl aniline (DMAN) and diethyl aniline (DEAN) on emission properties of a coumarin derivative 6-methyl-3azidoacetyl coumarin (6M3AAC) in acetonitrile was studied by means of steady state fluorescence spectroscopy. The quenching of fluorescence intensity was observed in the presence of amines. The quenching process was characterized b...

The interaction between bovine serum albumin (BSA) and atazanvir sulphate (AS) has been investigated under the physiological pH 7.4 condition using fluoresence spectroscopy. The binding constant, number of binding site, thermodynamic parameters such as ∆G, ∆H, ∆S and nature of binding forces between BSA-AS have been obtained from the steady state fluorescence quenching of BSA by AS. The static ...

Fluorescence quenching is a valuable tool to gain insight about dynamic changes of fluorophores in complex systems. Graphene (G), a single-layered 2D nanomaterial with unique properties, was dispersed in surfactant aqueous solutions of different nature: non-ionic polyoxyethylene-23-lauryl ether (Brij L23), anionic sodium dodecylsulphate (SDS), and cationic hexadecyltrimethylammonium bromide (CT...

Most studies of nucleotide binding to catalytic sites of Escherichia coli betaY331W-F(1)-ATPase by the quenching of the betaY331W fluorescence have been conducted in the presence of approximately 20 mM sulfate. We find that, in the absence of sulfate, the nucleotide concentration dependence of fluorescence quenching induced by ADP, ATP, and MgADP is biphasic, revealing two classes of binding si...

The article presents influence of pH and glucose concentration on phenylboronic acid (PBA) fluorescence studied by steady-state and time-resolved measurements. Fluorescence of PBA decreases with growing pH. These changes reflected acid-base equilibrium of PBA and allowed to estimate value of pKd as 9.2, which is comparable with literature data. Fluorescence intensity of phenylboronic acid is qu...

A conjugate of the high affinity benzodiazepine receptor ligand Ro 15-1788 and the fluorescent 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD) moiety was synthesized. This novel compound (BD 623) exhibited excitation and emission maxima at 486 and 542 nm, respectively, and possessed fluorescent properties that are dependent upon the polarity of its environment. BD 623 bound reversibly to benzodiazepine...

The rates of the quenching and recovery of tryptophan fluorescence are determined in the microsecond-millisecond time scale during the photocycle of bacteriorhodopsin under different perturbations. The kinetics suggest the presence of two quenching processes, a rapid one (on the time scale of photocycle intermediate L550 formation or faster) and a slow one (slightly slower than the slow compone...

Background: Azo dyes are the most widely used synthetic colorants in the textile, food, pharmaceutical, cosmetic, and other industries, accounting for nearly 70% of all dyestuffs consumed. Recently, much research attention has been paid to efficient monitoring of these hazardous chemicals and their related metabolites because of their potentially harmful effect on environmental issues. In contr...