Eumelanin-Based Organic Bioelectronics: Myth or Reality?

• DOI: 10.1557/adv.2015.49
• Publication Date: 2016-01-04T08:44:44Z
• Authors: Mario Barra; Irene Bonadies; Cosimo Carfagna; Antonio Cassinese; Francesca Cimino; Orlando Crescenzi; Valeria Criscuolo; d’Ischia Marco; Maria Grazia Magl...; Paola Manini; Ludovico Migliaccio; Anna Musto; Alessandra Napoli...; Angelica Navarra; Lucia Panzella; Silvia Parisi; Alessandro Pezzella; Carmela Tania Pro...; Paolo Tassini
• Keywords: optoelectronic;coating;biomaterial; Bioelectronics; Eumelanin; 01 natural sciences; 0104 chemical sciences

Eumelanins, the black insoluble pigments of human skin, eyes and substantia nigra (neuromelanin), stand today as a unique source of inspiration for the design and implementation of soft biocompatible multifunctional materials for bio-optoelectronic devices. Interest in eumelanins stems from bioavailability, biocompatibility and a peculiar set of physicochemical properties, i.e. broadband absorption in the UV-visible range, intrinsic free radical character, water-dependent hybrid ionic-electronic conductor behaviour, supporting optimistic feelings about a possible rise of eumelanin-mimics as innovative bioinspired solutions for organic bioelectronics. However, a number of conceptual and technological gaps still hinder a rapid progress of melanin-based organic electronics and bioelectronics, including in particular the limited contribution of electronic conductivity and current decay with time under biasing. Herein, we provide a concise overview of the structural and optoelectronic properties of melanins with a view to bringing to focus main issues and challenges en route to bioelectronic applications.