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"Smart" diblock copolymers as templates for magnetic-core gold-shell nanoparticle synthesis.

ABSTRACT: We report a new strategy for synthesizing temperature-responsive gamma-Fe(2)O(3)-core/Au-shell nanoparticles (Au-mNPs) from diblock copolymer micelles. The amphiphilic diblock copolymer chains were synthesized using reversible addition-fragmentation chain-transfer (RAFT) with a thermally responsive "smart" poly(N-isopropylacrylamide) (pNIPAAm) block and an amine-containing poly(N,N-dimethylaminoethylacrylamide) (DMAEAm) block that acted as a reducing agent during gold shell formation. The Au-mNPs reversibly aggregated upon heating the solution above the transition temperature of pNIPAAm, resulting in a red-shifted localized surface plasmon resonance.

SUBMITTER: Nash MA

PROVIDER: S-EPMC2806508 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature

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"Smart" diblock copolymers as templates for magnetic-core gold-shell nanoparticle synthesis.

Nash Michael A MA Lai James J JJ Hoffman Allan S AS Yager Paul P Stayton Patrick S PS

Nano letters 20100101 1

We report a new strategy for synthesizing temperature-responsive gamma-Fe(2)O(3)-core/Au-shell nanoparticles (Au-mNPs) from diblock copolymer micelles. The amphiphilic diblock copolymer chains were synthesized using reversible addition-fragmentation chain-transfer (RAFT) with a thermally responsive "smart" poly(N-isopropylacrylamide) (pNIPAAm) block and an amine-containing poly(N,N-dimethylaminoethylacrylamide) (DMAEAm) block that acted as a reducing agent during gold shell formation. The Au-mNP ...[more]

PMID: 20017498

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