Probing the heterogeneous structure of eumelanin using ultrafast vibrational fingerprinting.

ABSTRACT: Eumelanin is a brown-black biological pigment with sunscreen and radical scavenging functions important to numerous organisms. Eumelanin is also a promising redox-active material for energy conversion and storage, but the chemical structures present in this heterogeneous pigment remain unknown, limiting understanding of the properties of its light-responsive subunits. Here, we introduce an ultrafast vibrational fingerprinting approach for probing the structure and interactions of chromophores in heterogeneous materials like eumelanin. Specifically, transient vibrational spectra in the double-bond stretching region are recorded for subsets of electronic chromophores photoselected by an ultrafast excitation pulse tuned through the UV-visible spectrum. All subsets show a common vibrational fi

SUBMITTER: Grieco C 

PROVIDER: S-EPMC7486937 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature