Temporal Modulation of Stem Cell Activity Using Magnetoactive Hydrogels.
Cell activity is coordinated by dynamic interactions with the extracellular matrix, often through stimuli-mediated spatiotemporal stiffening and softening. Dynamic changes in mechanics occur in vivo through enzymatic or chemical means, processes which are challenging to reconstruct in cell culture materials. Here a magnetoactive hydrogel material formed by embedding magnetic particles in a hydrogel matrix is presented whereby elasticity can be modulated reversibly by attenuation of a magnetic field. Orders of magnitude change in elasticity using low magnetic fields are shown and reversibility of stiffening with simple permanent magnets is demonstrated. The broad applicability of this technique is demonstrated with two therapeutically relevant bioactivities in mesenchymal stem cells: secretion of proangiogenic molecules, and dynamic control of osteogenesis. The ability to reversibly stiffen cell culture materials across the full spectrum of soft tissue mechanics, using simple materials and commercially available permanent magnets, makes this approach viable for a broad range of laboratory environments.
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
Amr A
AA
Abdeen
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
Junmin
J
Lee
Department of Mechanical Scienceand Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
N Ashwin
NA
Bharadwaj
Department of Mechanical Scienceand Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
Randy H
RH
Ewoldt
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA. kakilian@illinois.edu.
Kristopher A
KA
Kilian
D001672:Biocompatible Materials / Q000494:pharmacology; D018929:Cell Culture Techniques; D055119:Elastic Modulus / Q000187:drug effects; D004548:Elasticity / Q000187:drug effects; D005109:Extracellular Matrix / Q000187:drug effects; D006801:Humans; D020100:Hydrogels / Q000494:pharmacology*; D008280:Magnetics / Q000379:methods; D008422:Materials Testing / Q000379:methods; D059630:Mesenchymal Stem Cells / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects; D013234:Stem Cells / Q000187:drug effects*; D023822:Tissue Engineering / Q000379:methods
D001672:Biocompatible Materials; D020100:Hydrogels
biomedical applications; hydrogels; magnetic materials; stimuli responsive materials; tissue engineering