Ashkan Zare Karizak - Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
Ali Akbar Saboury - Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
Adeleh Divsalar - Department of Cell & Molecular Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
Bahram Goliaei - Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran

Beta-casein, a major milk protein, is amphiphilic and self-associates into micelles in aqueous solutions. In the present study, the effects of, Fe3O4 nano particles on the structure and function of β-casein were investigated using spectroscopic method of fluorescence at two temperatures of 25 and 37 °C. The resulted data from intrinsic fluorescence spectra of protein indicated that Fe3O4 nano particles can quench the fluorescence intensity of β-casein via a static mechanism of fluorescence quenching. Analysis of quenching data have represented that there is one binding site on β-casein for binding of Fe3O4 nano particles at both temperatures according to the Stern-Volmer curve of protein analyzing. As a result, it can be concluded that Fe3O4 nano particles can bind to the carrier protein of β-casein and change the structures of protein.

Fe3O4 nano particles, β-casein, Fluorescence, Binding site