Ellipsometric Study of Ferritin Clusters Adsorbed on Metasurface and Influenced by UV Irradiation

In the last decade, the metasurfaces tend to be used as a successful biosensing materials. In this study, amorphous silicon arrays of resonant nanostructures were used as a substrate for Ferritin protein adsorption. Ferritins are iron-storing proteins that play an essential role in the biochemical reactions and the iron transport of all living organisms. This study is motivated by the increased number of neurodegenerative and cancer diseases, where Ferritin plays a key role. The properties of the Ferritin clusters, adsorbed on a dielectric metasurface, were studied ellipsometrically as a function of UV irradiation. Our results show that the properties of the Ferritin clusters depend on the UV exposure time. Resulting either in an increase of the molecular density due to release of iron ions or in the deformation of the quaternary protein structure. The data show that the metasurfaces are applicable for analysis and characterization of biomolecules by ellipsometry.