BSA, zinc oxide, titanium oxide, cerium oxide, zeta potential, circular dichroism

Introduction Interactions of protein with nanoparticles are one of the most important things(aspect) for the application of nanomaterials in the field of medicine. The use of nanomaterials is growing and from this point of view is important to study the possible impact of the nanomaterials!!!! on the human body. In our study we are interested in adsorption of BSA (bovine serum albumin), as a model protein, on metal oxide nanoparticles (ZnO, CeO2, TiO2). Methods The interactions between BSA and metal oxide nanoparticles were studied. Samples were prepared under predetermined conditions. The amount of 5, 10, 20, 50, 100, 200, 500 and 1000 ppm od BSA was added into 1000 ppm of ZnO, CeO2 and TiO2 nanoparticles. Adsorption of particles took place at a pH where the zeta potential of the protein and nanoparticles was opposite. Then the zeta potential and size distribution were measured and we determined the amount of protein needed to reduce the zeta potential of nanoparticles to zero. These parameters were measured by Zetasizer NanoZS (Malvern instrument, UK). Zeta potential was measured by Electrophoresis and Laser Doppler Velocimetry and the particle size distribution by Dynamic Light Scattering. Also the changes of BSA structure were observed by Circular dichroism (J-815 Jasco, USA). Results and discussion The zeta potential and size distribution were determined of prepared solutions of BSA and metal oxide nanoparticles. We confirmed the change of BSA structure after the adsorption on nanoparticles.