Reverse Engineering To Characterize Redox Properties: Revealing Melanin's Redox Activity through Mediated Electrochemical Probing
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Tarih
2018
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Amer Chemical Soc
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Melanins are ubiquitous in nature, yet their functions remain poorly understood, because their structures and properties elude characterization by conventional methods. Since many of the proposed functions of melanins (e.g., antioxidant, pro-oxidant, and radical scavenging) involve an exchange of electrons, we developed an electrochemical reverse engineering methodology to probe the redox properties of melanin. This mediated electrochemical probing (MEP) method (i) characterizes insoluble melanin particles that are localized adjacent to an electrode within a permeable hydrogel film, (ii) employs diffusible mediators to shuttle electrons between the electrode and melanin sample, and (iii) imposes complex sequences of input voltages and analyzes output response characteristics (e.g., currents) to reveal redox properties. Here, we illustrate the versatility of MEP and review results demonstrating that melanins have reversible redox activities, can exchange electrons with various reductants and oxidants, and can quench radicals either by donating or accepting electrons. These results suggest possible biological functionalities for melanin and motivate the use of MEP for characterizing additional (i.e., synthesized) materials whose functions rely on redox properties. More broadly, MEP is revealing a richness to redox activities that has previously been inaccessible to investigation.
Açıklama
Temocin, Zulfikar/0000-0001-7151-9772; Panzella, Lucia/0000-0002-2662-8205; Payne, Gregory/0000-0001-6638-9459
Anahtar Kelimeler
Kaynak
Chemistry Of Materials
WoS Q Değeri
Q1
Scopus Q Değeri
Cilt
30
Sayı
17
Künye
closedAccess
