Investigation on the effect of fluorescence quenching of bovine serum albumin by cefoxitin sodium using fluorescence spectroscopy and synchronous fluorescence spectroscopy

Abstract

The reaction mechanism of cefoxitin sodium with bovine serum albumin was investigated using fluorescence spectroscopy and synchronous fluorescence spectroscopy at different temperatures. The results showed that the change of binding constant of the synchronous fluorescence method with increasing temperature could be used to estimate the types of quenching mechanisms of drugs with protein and was consistent with one of fluorescence quenching method. In addition, the number of binding sites, type of interaction force, cooperativity between drug and protein and energy-transfer parameters of cefoxitin sodium and bovine serum albumin obtained from two methods using the same equation were consistent. Electrostatic force played a major role in the conjugation reaction between bovine serum albumin and cefoxitin sodium, and the type of quenching was static quenching. The primary binding site for cefoxitin sodium was sub-hydrophobic domain IIA, and the number of binding sites was 1. The value of Hill's coefficients (nH ) was approximately equal to 1, which suggested no cooperativity in the bovine serum albumin-cefoxitin sodium system. The donor-to-acceptor distance r < 7 nm indicated that static fluorescence quenching of bovine serum albumin by cefoxitin sodium was also a non-radiation energy-transfer process. The results indicated that synchronous fluorescence spectrometry could be used to study the reaction mechanism between drug and protein, and was a useful supplement to the conventional method. Copyright © 2015 John Wiley & Sons, Ltd.

Interactions of linagliptin, rabeprazole sodium, and their formed complex with bovine serum albumin: Computational docking and fluorescence spectroscopic methods

“…In this study, the theoretical values k 2 = 2/3, n = 1.34, and Ф = 0.15 were collected from previously published concepts, 23,30 and the calculated areas from the curves of Figure 6 are listed in Table 5. The calculated average distances of these ligands from protein were observed below 7 nm, which indicated that the energy transfer occurred with a high possibility from BSA to drug molecules or their formed complex 8 . As temperature variation has not outright correlation on the nonradioactive energy transformation, 9 this study established the energy transfer profile at one temperature (298 K).…”

“…The curves of the fluorescence spectrum of the bovine serum albumin and absorption spectrum of the ligand overlaid that indicated the higher possibility of the existence of energy transfer between donor and acceptor molecules from BSA to drug molecules or their formed complex. 8 As temperature variation has not outright correlation on the nonradioactive energy transformation, 9 this study established the energy transfer profile at one temperature (298 K). Moreover, it is vital to note here that the calculated distance between the protein and ligand (r) was larger than the value of critical distance (R 0 ) located at 50% energy transfer efficiency, which indicated the fluorescence quenching mechanism of the biomolecule was an obvious static process mediated by these three LG, linagliptin; RS, rabeprazole sodium.…”

Molecular Assessment of the Toxic Mechanism of the Latest Neonicotinoid Dinotefuran with Glutathione Peroxidase 6 from Arabidopsis thaliana

“…However, the quenching constants of static quenching decrease with the increase in temperature because of the instability of the complex . In order to further explore the fluorescence quenching mechanism of dinotefuran toward AtGPX6 at different temperatures, the Stern–Volmer linear equation was used to describe the fluorescence quenching data: In this equation, F 0 and F are the relative fluorescence intensities of AtGPX6 in the absence and presence of dinotefuran, respectively. K SV denotes the dynamic quenching constant, and [ Q ] is the concentration of dinotefuran.…”

Effect of alkyl distribution in pyrazine on pyrazine flavor release in bovine serum albumin solution

“…The interaction forces may be the weak interaction force, such as hydrogen bonding, van der Waals force, hydrophobic effect and electrostatic interaction, which are the main interactions between a small molecule and biological macromolecule. 52,53 The specic interactions can be determined based on the enthalpy change (DH) and entropy change (DS) in the…”