Synthesis of soluble melanin nanoparticles under acidic conditions using tyrosinase and their characterization.

Melanin nanoparticles (MNPs) used for biomedical applications are often synthesized the chemical auto-oxidation of catecholic monomers such as dopamine and 3,4-dihydroxyphenylalanine (DOPA) under alkaline conditions. However, the synthetic method for the chemical synthesis of MNP (cMNP) is relatively straightforward and more robust to control their homogenous particle size and morphology than the corresponding enzymatic synthetic methods. In this study, we demonstrated that the simple enzymatic synthesis of MNPs (eMNPs) with homogenous and soluble (<20 nm diameter) properties is possible using dopamine and tyrosinase (Ty) under acidic conditions (, pH 3.