title: Ultra-soft PDMS-based magnetoactive elastomers as dynamic cell culture substrata.
abstract: Mechanical cues such as extracellular matrix stiffness and movement have a major impact on cell differentiation and function. To replicate these biological features in vitro, soft substrata with tunable elasticity and the possibility for controlled surface translocation are desirable. Here we report on the use of ultra-soft (Young's modulus <100 kPa) PDMS-based magnetoactive elastomers (MAE) as suitable cell culture substrata. Soft non-viscous PDMS (<18 kPa) is produced using a modified extended crosslinker. MAEs are generated by embedding magnetic microparticles into a soft PDMS matrix. Both substrata yield an elasticity-dependent (14 vs. 100 kPa) modulation of α-smooth muscle actin expression in primary human fibroblasts. To allow for static or dynamic control of MAE material properties, we devise low magnetic field (≈40 mT) stimulation systems compatible with cell-culture environments. Magnetic field-instigated stiffening (14 to 200 kPa) of soft MAE enhances the spreading of primary human fibroblasts and decreases PAX-7 transcription in human mesenchymal stem cells. Pulsatile MAE movements are generated using oscillating magnetic fields and are well tolerated by adherent human fibroblasts. This MAE system provides spatial and temporal control of substratum material characteristics and permits novel designs when used as dynamic cell culture substrata or cell culture-coated actuator in tissue engineering applications or biomedical devices.
authors.affiliation: Department of Electrical Engineering and Information Technology, Regensburg University of Applied Sciences, Regensburg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Mayer
authors.forename: Raman
authors.initials: R
authors.lastname: Rabindranath
authors.forename: Juliane
authors.initials: J
authors.lastname: Börner
authors.forename: Eva
authors.initials: E
authors.lastname: Hörner
authors.forename: Alexander
authors.initials: A
authors.lastname: Bentz
authors.forename: Josefina
authors.initials: J
authors.lastname: Salgado
authors.forename: Hong
authors.initials: H
authors.lastname: Han
authors.forename: Holger
authors.initials: H
authors.lastname: Böse
authors.forename: Jörn
authors.initials: J
authors.lastname: Probst
authors.forename: Mikhail
authors.initials: M
authors.lastname: Shamonin
authors.forename: Gareth J
authors.initials: GJ
authors.lastname: Monkman
authors.forename: Günther
authors.initials: G
authors.lastname: Schlunck
mesh_terms: D018929:Cell Culture Techniques; D020405:Dermis / Q000166:cytology; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D055119:Elastic Modulus / Q000528:radiation effects; D020724:Elastomers / Q000737:chemistry; D005109:Extracellular Matrix; D005347:Fibroblasts; D006801:Humans; D060526:Magnetic Fields; D040542:Mechanotransduction, Cellular / Q000502:physiology* / Q000528:radiation effects; D009757:Nylons / Q000737:chemistry; D012828:Silicones / Q000737:chemistry
chemical_list: D004129:Dimethylpolysiloxanes; D020724:Elastomers; D009757:Nylons; D012828:Silicones; C085707:poly(dimethylsiloxane)-polyamide copolymer