Artículos de revistas
Synthetic melanin thin films: Structural and electrical properties
Registro en:
Journal Of Applied Physics. Amer Inst Physics, v. 96, n. 10, n. 5803, n. 5807, 2004.
0021-8979
WOS:000224926000067
10.1063/1.1803629
Autor
da Silva, MIN
Deziderio, SN
Gonzalez, JC
Graeff, CFO
Cotta, MA
Institución
Resumen
Scanning probe microscopy was used to investigate the structural and electrical organization at the nanoscopic level of hydrated melanin thin films synthesized by oxidizing L-3-(3,4-dihydroxyphenyl)-alanine (L-dopa) in dimethyl sulfoxide. Atomic force microscopy (AFM) provided the morphologies of the L-dopa melanin films. Electrostatic force microscopy and conductive-AFM were used to spatially resolve the electrical properties of the material. Using a simple parallel plate capacitor model a method to measure the charge distribution on the sample was developed. The correlations between topography, electric charge, and current images of the sample demonstrated that the hydration process produces a restructuring of melanin observed not only through topographic variations, but also through the creation of areas with different electrical properties. (C) 2004 American Institute of Physics. 96 10 5803 5807