The R-lines of the Mn4+ fluorescence. associated with 2~ -, 4~~ transitions in gadolinium gallium garnet exhibits large broadening as compared with other ions with d3 shell. The laser excitation and fluorescence spectra without magnetic field show that this i s partially inhomogeneous broadening related t o presence of charge-compensating c a 2 + ions. Remaining part of the broadening is due to...

The interactions of cefoperazone sodium with bovine transferrin and bovine serum albumin were studied by multi-spectroscopic methods. Results showed that the intrinsic fluorescence of proteins was quenched by the cefoperazone sodium with a static quenching procedure. The thermodynamics parameters indicated that electrostatic attraction played a major role in the interactions of drug and protein...

BACKGROUND Nanoparticles (NPs) entering the biological environment could interact with biomolecules, but little is known about the interaction between unsaturated fatty acids (UFA) and NPs. METHODS This study used α-linolenic acid (LNA) complexed to bovine serum albumin (BSA) for UFA and HepG2 cells for hepatocytes. The interactions between BSA or LNA and ZnO NPs were studied. RESULTS The p...

Rosmarinic acid (RA) is an importantly and naturally occurring polyphenol from plants of the mint family with potent biological activities. Here, the in vitro interaction of RA with bovine serum albumin (BSA) has been investigated using various biophysical approaches as well as molecular modeling methods, to ascertain its binding mechanism and conformational changes. The fluorescence results de...

For the first time, the binding of ropinirole hydrochloride (ROP) and aspirin (ASA) to human holo-transferrin (hTf) has been investigated by spectroscopic approaches (fluorescence quenching, synchronous fluorescence, time-resolved fluorescence, three-dimensional fluorescence, UV-vis absorption, circular dichroism, resonance light scattering), as well as zeta potential and molecular modeling tec...

A rapid, novel spectrofluorimetric method to determine epristeride (EP) in biological fluids and a pharmaceutical formulation was developed, based on the fact that fluorescence intensity of l-tryptophan could be quenched by EP in the medium of pH=9.0. The various factors influencing fluorescence quenching were discussed. The quenching mechanism was investigated with the quenching type, synchron...

Second order advantage of excitation-emission fluorescence matrix was applied for the simultaneous determination of ibuprofen and caffeine. The proposed method is based on the measurement of the native fluorescence and recording emission spectra of ibuprofen and caffeine in different excitation wavelengths. The mixture of these compounds was resolved by multivariate curve resolution coupled wit...