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Active scaffolds for on-demand drug and cell delivery.

ABSTRACT: Porous biomaterials have been widely used as scaffolds in tissue engineering and cell-based therapies. The release of biological agents from conventional porous scaffolds is typically governed by molecular diffusion, material degradation, and cell migration, which do not allow for dynamic external regulation. We present a new active porous scaffold that can be remotely controlled by a magnetic field to deliver various biological agents on demand. The active porous scaffold, in the form of a macroporous ferrogel, gives a large deformation and volume change of over 70% under a moderate magnetic field. The deformation and volume variation allows a new mechanism to trigger and enhance the release of various drugs including mitoxantrone, plasmid DNA, and a chemokine from the scaffold. The porous scaffold can also act as a depot of various cells, whose release can be controlled by external magnetic fields.

SUBMITTER: Zhao X

PROVIDER: S-EPMC3017202 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Active scaffolds for on-demand drug and cell delivery.

Zhao Xuanhe X Kim Jaeyun J Cezar Christine A CA Huebsch Nathaniel N Lee Kangwon K Bouhadir Kamal K Mooney David J DJ

Proceedings of the National Academy of Sciences of the United States of America 20101213 1

Porous biomaterials have been widely used as scaffolds in tissue engineering and cell-based therapies. The release of biological agents from conventional porous scaffolds is typically governed by molecular diffusion, material degradation, and cell migration, which do not allow for dynamic external regulation. We present a new active porous scaffold that can be remotely controlled by a magnetic field to deliver various biological agents on demand. The active porous scaffold, in the form of a macr ...[more]

PMID: 21149682

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