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Mechano-Responsive Hydrogels Crosslinked by Block Copolymer Micelles.

ABSTRACT: Block copolymer micelles (BCMs) were prepared from amphiphilic diblock copolymers of poly(n-butyl acrylate) and poly(acrylic acid) partially modified with 2-hydroxyethyl acrylate. Radical polymerization of acrylamide in the presence of micellar crosslinkers gave rise to elastomeric hydrogels (BCM-PAAm) whose mechanical properties can be tuned by varying the BCM composition. Transmission electron microscopy (TEM) imaging revealed stretch-induced, reversible micelle deformation in BCM-PAAm gels. A model hydrophobic drug, pyrene, loaded into the micelle core prior to the formation of BCM-PAAm gels, was dynamically released in response to externally applied mechanical forces. The BCM-crosslinked hydrogels with combined strength and force-modulated drug release are attractive candidates for the repair and regeneration of mechanically-active tissues.

SUBMITTER: Xiao L

PROVIDER: S-EPMC3459338 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Mechano-Responsive Hydrogels Crosslinked by Block Copolymer Micelles.

Xiao Longxi L Zhu Jiahua J Londono David J DJ Pochan Darrin J DJ Jia Xinqiao X

Soft matter 20121001 40

Block copolymer micelles (BCMs) were prepared from amphiphilic diblock copolymers of poly(n-butyl acrylate) and poly(acrylic acid) partially modified with 2-hydroxyethyl acrylate. Radical polymerization of acrylamide in the presence of micellar crosslinkers gave rise to elastomeric hydrogels (BCM-PAAm) whose mechanical properties can be tuned by varying the BCM composition. Transmission electron microscopy (TEM) imaging revealed stretch-induced, reversible micelle deformation in BCM-PAAm gels. A ...[more]

PMID: 23024698

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