Spin Plasmonics and Surface Enhanced Raman Spectroscopy in Label Free Biomolecular Sensing

This work is part of a study focused on surface enhanced Raman scattering of biomolecules using magnetic-plasmonic nanostructured substrates. The substrates are nanostructured Fe ₃ O ₄ coated with Au and Ag, respectively. Fe ₃ O ₄ has an inverse spinel structure and a magnetic moment of 4.1μ _B /f.u, a Curie temperature T _C = 850 K and is a conductive oxide at room temperature. The Fe ₃ O ₄ nanocompound was prepared via green synthesis. Gold/silver nanocoatings were deposited by drop-cast from cyanide free solutions. The effect of the spin-plasmonic structures on the SERS effect is investigated through label free SERS measurements on traces of body fluids and submicron fragments of animal tissue. The enhancement factor is compared with that resulted from SERS experiments on twin samples deposited on Au and Ag nanostructured surfaces. We foresee applications in histopathology and forensics.