The interaction between ionic liquids modified magnetic nanoparticles and bovine serum albumin and the cytotoxicity to HepG-2 cells.

The interaction between ionic liquids modified magnetic Fe3O4 (Fe2) and bovine serum albumin (BSA) is reported and is compared with NH2 functionalized magnetic nanoparticles Fe3O4 (Fe1) based on the UV-visible spectrum, steady-state fluorescence measurements, synchronous fluorescence and DSC methods. The results indicate a static quenching mechanism operating in both nanoparticles. The binding constant of the Fe2-BSA complex calculated from fluorescence data shows that BSA has a low binding affinity for Fe2 than Fe1. DSC data reveal that the thermal stability process of BSA in the Fe2-BSA complex is semi-reversible. This demonstrates that the ionic liquid modified magnetic nanoparticles (Fe2) enhance the thermostability of BSA in the range of 20-40°C, and protein attached Fe2 has higher thermal stability than free BSA. Moreover, the in vitro assay results show that Fe2 shows low cytotoxicity to HepG-2 cells.