São Paulo State University (UNESP) , School of Sciences, Postgraduate Program in Materials Science and Technology (POSMAT) , Bauru 17033-360 , Brazil.
São Paulo State University (UNESP) , Campus of Itapeva, Itapeva 18409-010 , Brazil.
J Phys Chem B. 2019 Feb 14;123(6):1248-1255. doi: 10.1021/acs.jpcb.8b09694. Epub 2019 Jan 30.
Melanins are natural pigments with promising bioelectronic applications. Among their unique properties, the existence of a persistent paramagnetic signal can be considered one of the most intriguing and controversial features. Additionally, the possible influence of such centers on charge transport accentuates the need for a better understanding of their origin and specific characteristics. In this report, electron paramagnetic resonance spectra of melanin samples obtained at different experimental conditions were systematically studied. From the fitting procedure, three distinct resonant lines are proposed, two associated with carbon-centered radicals and one with semiquinone free radicals.
黑色素是具有广阔生物电子应用前景的天然色素。在其独特的性质中，持久的顺磁信号的存在可以被认为是最有趣和最具争议的特征之一。此外，这种中心对电荷输运的可能影响突出了更好地理解其起源和特定特征的必要性。在本报告中，系统地研究了在不同实验条件下获得的黑色素样品的电子顺磁共振谱。通过拟合程序，提出了三个不同的共振线，两个与碳中心自由基有关，一个与半醌自由基有关。
