Adsorption characteristics of bovine serum albumin onto α-Fe₂O₃ nanoparticles prepared via the alcohol solution combustion process of ferric nitrate

Abstract

The α-Fe2O3 nanoparticles were prepared via the alcohol solution combustion process of ferric nitrate. The scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS). X-ray diffraction (XRD), and vibrating sample magnetometer (VSM) were taken to characterize the prepared α-Fe2O3 nanoparticles. The average particle sizes of the as-prepared α-Fe2O3 nanoparticles were approximately 180 nm, and their magnetic property was approximately 0.42 emu·g-1 after the measurement. The different concentrations of BSA solutions and the adsorption times were investigated to investigate the adsorption characteristics of bovine serum albumin (BSA) onto α-Fe2O3 nanoparticles. For larger adsorption capacity and higher removal rate, the dose of α-Fe2O3 nanoparticles in aqueous solution was selected at 2.5 mg·mL-1. The adsorption process of BSA onto α-Fe2O3 nanoparticles conformed to the pseudo-first-order kinetic model. While, the correlation coefficient (R2) of the Temkin isothermal model was higher than Langmuir model and Freundlich isothermal model, suggesting that the isothermal model of BSA onto α-Fe2O3 nanoparticles was more in line with Temkin isotherm model. Which suggested that the adsorption behavior of magnetic α-Fe2O3 nanoparticles for BSA belonged to multi-molecular layer chemisorption. When BSA concentration was 600 mg·L-1 and the pH of solution was 5, the adsorption capacity of BSA onto magnetic α-Fe2O3 nanoparticles achieved 114.2 mg·g-1, and the adsorption rate could still reach 70.3% of the first time after 7 cycles.