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Structure and Function of Iron-Loaded Synthetic Melanin.

ABSTRACT: We describe a synthetic method for increasing and controlling the iron loading of synthetic melanin nanoparticles and use the resulting materials to perform a systematic quantitative investigation on their structure-property relationship. A comprehensive analysis by magnetometry, electron paramagnetic resonance, and nuclear magnetic relaxation dispersion reveals the complexities of their magnetic behavior and how these intraparticle magnetic interactions manifest in useful material properties such as their performance as MRI contrast agents. This analysis allows predictions of the optimal iron loading through a quantitative modeling of antiferromagnetic coupling that arises from proximal iron ions. This study provides a detailed understanding of this complex class of synthetic biomaterials and gives insight into interactions and structures prevalent in naturally occurring melanins.

SUBMITTER: Li Y

PROVIDER: S-EPMC5295137 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Structure and Function of Iron-Loaded Synthetic Melanin.

Li Yiwen Y Xie Yijun Y Wang Zhao Z Zang Nanzhi N Carniato Fabio F Huang Yuran Y Andolina Christopher M CM Parent Lucas R LR Ditri Treffly B TB Walter Eric D ED Botta Mauro M Rinehart Jeffrey D JD Gianneschi Nathan C NC

ACS nano 20161101 11

We describe a synthetic method for increasing and controlling the iron loading of synthetic melanin nanoparticles and use the resulting materials to perform a systematic quantitative investigation on their structure-property relationship. A comprehensive analysis by magnetometry, electron paramagnetic resonance, and nuclear magnetic relaxation dispersion reveals the complexities of their magnetic behavior and how these intraparticle magnetic interactions manifest in useful material properties su ...[more]

PMID: 27802021

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