Surface-enhanced magneto-Raman spectroscopy of ferritin

COLL 335

Danilo Romero1, Guangjun Cheng2, David Dunmire2, and Angela R. Hight Walker2. (1) Laboratory for Physical Sciences, University of Maryland, College Park, MD 20742, (2) Physics Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20889
We investigate the effects of an externally applied magnetic field on the structure and magnetic properties of ferritin. The measurements were carried out over a wide range of temperatures (T=4.2K to 300K) and magnetic fields (B=0 to 8 Tesla) using a new magneto-Raman confocal microscope system. Dilute concentration of ferritin is dispersed on patterned gold surfaces for surface-enhanced Raman spectroscopy to achieve sensitivities approaching single molecule. By scanning a diffraction-limited laser spot on this surface, individual and near-neighbor ferritin molecules can be detected. The effects of an applied magnetic field on the vibrational and magnetic Raman spectra of isolated as well as interacting ferritin molecules will be explored in this talk.