YYY Dynamic Tuning of Viscoelastic Hydrogels with Carbonyl Iron Microparticles Reveals the Rapid Response of Cells to Three-Dimensional Substrate Mechanics

Authors

Kiet A. Tran, Rowan University
Emile Kraus, University of Pennsylvania
Andy T. Clark, Bryn Mawr CollegeFollow
Alex Bennet, University of Pennsylvania
Katarzyna Pogoda, Institute of Nuclear Physics, Polish Academy of Sciences
Xuemei Cheng, Bryn Mawr CollegeFollow
Andrejs Cēbers, University of Latvia
Paul A. Janmey, University of Pennsylvania
Peter A. Galie, Rowan University

Document Type

Article

Version

Author's Final Manuscript

Publication Title

Applied Materials & Interfaces

Volume

13

Publication Date

2021

Abstract

Current methods to dynamically tune three-dimensional hydrogel mechanics require specific chemistries and substrates that make modest, slow, and often irreversible changes in their mechanical properties, exclude the use of protein-based scaffolds, or alter the hydrogel microstructure and pore size. Here, we rapidly and reversibly alter the mechanical properties of hydrogels consisting of extracellular matrix proteins and proteoglycans by adding carbonyl iron microparticles (MPs) and applying external magnetic fields. This approach drastically alters hydrogel mechanics: rheology reveals that application of a 4000 Oe magnetic field to a 5 mg/mL collagen hydrogel containing 10 wt % MPs increases the storage modulus from approximately 1.5 to 30 kPa. Cell morphology experiments show that cells embedded within these hydrogels rapidly sense the magnetically induced changes in ECM stiffness. Ca2+ transients are altered within seconds of stiffening or subsequent softening, and slower but still dynamic changes occur in YAP nuclear translocation in response to time-dependent application of a magnetic field. The near instantaneous change in hydrogel mechanics provides new insight into the effect of changing extracellular stiffness on both acute and chronic changes in diverse cell types embedded in protein-based scaffolds. Due to its flexibility, this method is broadly applicable to future studies interrogating cell mechanotransduction in three-dimensional substrates.

Citation

Tran, K. A., Kraus, E., Clark, A. T., Bennett, A., Pogoda, K., Cheng, X., Ce̅bers, A., Janmey, P.A., and P. A. Galie. "Dynamic Tuning of Viscoelastic Hydrogels with Carbonyl Iron Microparticles Reveals the Rapid Response of Cells to Three-Dimensional Substrate Mechanics." ACS: Applied Materials & Interfaces 13.18: 20947-20959.

DOI

http://doi.org/10.1021/acsami.0c21868