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In this work, the binding interaction of fluvastatin (FLU) and pit-avastatin (PIT) with bovine β-casein (β-CN) were performed under physiological conditions (pH 7.2) by fluorescence emission spectroscopy, synchronous fluorescence spectroscopy, Fourier transform infrared spectroscopy (FTIR) and molecular docking methods. Due to the formation of FLU-β-CN and PIT-β-CN complexes, the intrinsic fluorescence of β-CN was quenched. The number of bound FLU and PIT per protein molecule (n) were about 1, also the binding constant of FLU-β-CN and PIT-β-CN complexes were 7.96×104 and 3.44×104 M-1 at 298 K, respectively. This result suggests that the binding affinity of FLU to β-CN was higher than that for PIT. Molecular modelling showed different binding sites for FLU and PIT on β-CN. All these experimental results suggest that β-CN can be used as a carrier protein which delivers FLU and PIT based drugs to target molecules.

Kinetic Monte Carlo modeling was employed as a powerful tool to kinetically investigate of ibuprofen removal by direct ozonation (O3 alone) and heterogeneous catalytic ozonation (graphene oxide and graphene oxide loaded with Fe3O4). The kinetic mechanisms and the values of rate constants for each step of the suggested mechanisms were found by Monte Carlo simulation. The graphene oxide loaded with Fe3O4 displays a significant role as a heterogeneous catalyst in the ozonation of ibuprofen by enhancing the reactivity of ibuprofen drug and O3 on the graphene oxide surface. Optimized values of catalysts and O3 were attained through obtaining the effect of initial O3 and catalyst amounts on the rate of ibuprofen elimination utilizing kinetic Monte Carlo simulation. The simulation outcomes of the present investigation demonstrate satisfactory agreement with the experimental ozonation data for the systems above. [ABSTRACT FROM AUTHOR]

Kinetic Monte Carlo simulation was applied to study the mechanism of antibiotics elimination in aqueous solution systems by ZnO/UV and TiO2/UV catalytic systems. The investigated antibiotics in this research are amoxicillin, ampicillin, and cloxacillin. The kinetic mechanisms and the values of rate constants for each step of the proposed mechanisms were obtained by kinetic Monte Carlo simulation. The simulation outcomes of the present investigation demonstrate satisfactory agreement with the experimental photo-degradation data for the aforementioned drugs. [ABSTRACT FROM AUTHOR]

The (E)‐2‐hydroxy‐5‐(aryldiazenyl) benzaldehydes (azo dyes 1–4) were synthesized in high purity. As they are insoluble in water, the usual analytical methods cannot be utilized to determine their pKa values. Cyclic voltammetry was experimentally used to determine their pKa values in DMSO solvent. In addition, computational methods and a conductor‐like screening model (COSMO) were used to calculate the solvent effect. ΔUexchange°, ΔGexchange°, Kexchange, and pKa values were estimated for the azo dyes being studied using the BP86, TPSS, B3LYP, PBE0, TPSSh, and PW6B95 density functionals in def2‐TZVP basis sets. The obtained mean absolute deviations (MADs) indicate that the results of BP86, PBE0, and PW6B95 functionals are in good agreement with experimental values. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (NPs) are used to a large extent in the targeted delivery of therapeutic agents. In this study, we aimed to investigate the possible toxicity of Fe2O3 NPs on human cells, including blood lymphocytes. We isolated blood lymphocytes from healthy humans using Ficoll polysaccharide and subsequently by gradient centrifugation. Then, the toxicity parameters, including cell viability, reactive oxygen species (ROS) formation, lipid peroxidation, cellular glutathione (GSH) level, mitochondrial and lysosomal damage, were measured in blood lymphocytes after exposure to Fe2O3 NPs. Our results indicated that Fe2O3 NPs significantly (dependent on concentration) reduced the cell viability, and the IC50 was determined to be 1 mM. With increasing concentrations, we found that Fe2O3 NPs-induced cell toxicity was associated with a significant increase in intracellular ROS and loss of mitochondrial membrane potential and lysosomal membrane leakiness. Consequently, these NPs at different concentrations affect GSH level and cause oxidative stress in human lymphocytes. [ABSTRACT FROM AUTHOR]

The interaction of nickel (II) phthalocyanine tetrasulfonic acid tetrasodium salt with bovine serum albumin (BSA) has been investigated by combination of fluorescence, UV-vis absorption, Fourier transform infrared (FT-IR), and circular dichorism (CD) spectroscopies as well as through molecular docking. Fluorescence quenching and absorption spectra were investigated as a mean for estimating the binding parameters. Analysis of fluorescence quenching data at different temperatures was performed in order to specify the thermodynamics parameters for interactions of phthalocyanine complex with BSA. According to experimental data it was suggested that phthalocyanine had a significant binding affinity to BSA and the process was entropy driven. Based on the results of molecular docking it was indicated that the main active binding site for this phthalocyanine complex is site I in subdomain IIA of BSA. The results provide useful information for understanding the binding mechanism of anticancer drug-albumin and gives insight into the biological activity and metabolism of the drug in blood. [ABSTRACT FROM AUTHOR]