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Synthesis of Ultrasmall Synthetic Melanin Nanoparticles by UV Irradiation in Acidic and Neutral Conditions.

ABSTRACT: Synthetic melanin nanoparticles have value in metal chelation, photoprotection, and biocompatibility. Applications of these materials have been reported in optics, biomedicine, and electronics. However, precise size control has remained relatively difficult-especially for materials below 1000 nm. In this paper we describe the synthesis of ultrasmall synthetic nanoparticles with size of 9.4-31.4 nm in weakly acidic and neutral conditions via UV-irradiation. Size control of these particles was possible by varying the pH from 6.4-10.0. We then used UV-vis, FTIR, and nuclear magnetic resonance to investigate the mechanism of UV-induced polymerization. The data show that reactive oxygen species from UV irradiation oxidizes intermediates of the reaction and accelerates the formation of these synthetic melanin structures.

SUBMITTER: Lemaster JE

PROVIDER: S-EPMC6953903 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Synthesis of Ultrasmall Synthetic Melanin Nanoparticles by UV Irradiation in Acidic and Neutral Conditions.

Lemaster Jeanne E JE Jeevarathinam Ananthakrishnan Soundaram AS Kumar Ajay A Chandrasekar Bhargavi B Chen Fang F Jokerst Jesse V JV

ACS applied bio materials 20190926 10

Synthetic melanin nanoparticles have value in metal chelation, photoprotection, and biocompatibility. Applications of these materials have been reported in optics, biomedicine, and electronics. However, precise size control has remained relatively difficult-especially for materials below 1000 nm. In this paper we describe the synthesis of ultrasmall synthetic nanoparticles with size of 9.4-31.4 nm in weakly acidic and neutral conditions via UV-irradiation. Size control of these particles was pos ...[more]

PMID: 31930189

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