title: Magnetic properties of synthetic eumelanin--preliminary results.
abstract: We report an experimental and theoretical study of magnetic properties of synthetic eumelanin. The magnetization curves are determined by using both a vibrating sample magnetometer and a superconducting quantum interferometer device in an extended range of magnetic fields ranging from -10 kOe to 10 kOe at different temperatures. We find that the eumelanin magnetization can be qualitatively explained in terms of a simple model of dipolar spheres with an intrinsic magnetic moment. The latter one is experimentally measured by using X-band electron paramagnetic resonance. Our findings indicate that synthetic melanins are superparamagnetic.
authors.affiliation: Centro Universitario de la Ciénega, Universidad de Guadalajara, Ocotlán, Jalisco, Mexico.
authors.forename: M E
authors.initials: ME
authors.lastname: Cano
authors.forename: R
authors.initials: R
authors.lastname: Castañeda-Priego
authors.forename: A
authors.initials: A
authors.lastname: Gil-Villegas
authors.forename: M A
authors.initials: MA
authors.lastname: Sosa
authors.forename: P
authors.initials: P
authors.lastname: Schio
authors.forename: A J A
authors.initials: AJ
authors.lastname: de Oliveira
authors.forename: F
authors.initials: F
authors.lastname: Chen
authors.forename: O
authors.initials: O
authors.lastname: Baffa
authors.forename: C F O
authors.initials: CF
authors.lastname: Graeff
mesh_terms: D003198:Computer Simulation; D004578:Electron Spin Resonance Spectroscopy; D008280:Magnetics; D008543:Melanins / Q000138:chemical synthesis / Q000737:chemistry*; D009010:Monte Carlo Method; D013696:Temperature
chemical_list: D008543:Melanins; C041877:eumelanin