Amyloid Fibers Increase Free Radicals of Synthetic Melanin

Abstract

Functional amyloid fibers are crucial in melanogenesis,but theirroles are incompletely understood. In particular, their relationshipwith intrinsic spin characters of melanin remains unexplored. Here,we show that adding an amyloid scaffold greatly augments the spindensity in synthetic melanin. It also brings about concurrent alterationsin water dispersibility, bandgaps, and radical scavenging propertiesof the synthetic melanin, which facilitates its applications in solarwater remediation and protection of human keratinocytes from UV irradiation.This work provides implications in the unrevealed role of functionalamyloid in melanogenesis and in the origin of the superiority of naturalmelanin toward its synthetic variants in terms of the spin-relatedproperties.