Enzyme‐Mediated In Situ Synthesis and Deposition of Nonaggregated Melanin Protoparticles

Abstract

The previously introduced process for enzyme‐mediated in situ synthesis and deposition of eumelanin is investigated with covalent immobilization of the tyrosinase. It results in a monolayer structure of non‐coalesced melanin particles, with a film thickness of 5–8 nm. The reaction is self‐terminating due to overlay of the enzymes with particles. The melanin particles are rodlike with lengths down to 6 nm. Isolated melanin structures of such small size have not been observed before and might be a kind of protoparticle in the supramolecular buildup of melanin oligomers. Utilization of melanin particles with such small size can enable nanotechnological applications in the areas of bioelectronics and biosensors. image