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Catechol Redox Induced Formation of Metal Core-Polymer Shell Nanoparticles.

ABSTRACT: A novel strategy was developed to synthesize polymer-coated metal nanoparticles (NPs) through reduction of metal cations with 3,4-dihydroxyphenylalanine (DOPA)-containing polyethylene glycol (PEG) polymers. Catechol redox chemistry was used to both synthesize metal NPs and simultaneously form a cross-linked shell of PEG polymers on their surfaces. DOPA reduced gold and silver cations into neutral metal atoms, producing reactive quinones that covalently cross-linked the PEG molecules around the surface of the NP. Importantly, these PEG-functionalized metal NPs were stable in physiological ionic strengths and under centrifugation, and hold broad appeal since they absorb and scatter light in aqueous solutions.

SUBMITTER: Black KC

PROVIDER: S-EPMC3109993 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Catechol Redox Induced Formation of Metal Core-Polymer Shell Nanoparticles.

Black Kvar C L KC Liu Zhongqiang Z Messersmith Phillip B PB

Chemistry of materials : a publication of the American Chemical Society 20110301 5

A novel strategy was developed to synthesize polymer-coated metal nanoparticles (NPs) through reduction of metal cations with 3,4-dihydroxyphenylalanine (DOPA)-containing polyethylene glycol (PEG) polymers. Catechol redox chemistry was used to both synthesize metal NPs and simultaneously form a cross-linked shell of PEG polymers on their surfaces. DOPA reduced gold and silver cations into neutral metal atoms, producing reactive quinones that covalently cross-linked the PEG molecules around the s ...[more]

PMID: 21666825

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