Synthetic melanin thin films:: Structural and electrical properties

被引:39
作者
da Silva, MIN
Dezidério, SN
Gonzalez, JC
Graeff, CFO
Cotta, MA
机构
[1] Univ Estadual Campinas, Inst Fis Gleb Wataghin, Dept Fis Aplicada, Lab Pesquisa Disposit, BR-13081970 Campinas, SP, Brazil
[2] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Fis & Matemat, BR-14040901 Sao Paulo, Brazil
[3] Lab Nacl Luz Sincrotron, Sao Paulo, Brazil
基金
巴西圣保罗研究基金会;
关键词
D O I
10.1063/1.1803629
中图分类号
O59 [应用物理学];
学科分类号
摘要
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.
引用
收藏
页码:5803 / 5807
页数:5
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