Melanins are a class of biopolymers that are widespread in nature and have diverse origins, chemical compositions, and functions. Their chemical, electrical, optical, and paramagnetic properties offer opportunities for applications in materials science, particularly for medical and technical uses. This review focuses on the application of analytical techniques to study melanins in multidisciplinary contexts with a view to their use as sustainable resources for advanced biotechnological applications, and how these may facilitate the achievement of the United Nations Sustainable Development Goals.
Metal chalcogenides are ubiquitous starting materials for the extraction of metals from both primary and secondary sources. In this study, it is shown that chalcogenide compounds are electrochemically active and can be solubilized from solid powders by electrochemical oxidation in a deep eutectic solvent. Importantly, the metal ions released into solution were unaffected by the type of chalcogenide present in the initial compound, maintaining the same speciation as would be obtained from dissolution of a chloride salt. Therefore, metals can be recovered by the same process from mixtures of chalcogenides. The chalcogenides form a mixture of oxyanions in the + IV and + VI oxidation states, which are separable via standard processes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.