Chemistry of Materials. Volume 31, Issue 14, 23 July 2019, Pages 5181-5189
In Situ Magnetic Alignment and Cross-Linking of Injectable Microparticles into Centimeter-Scale Fibers for Efficient Myoblast Alignment and in Vivo Fiber Formation(Article)
Seung Woo Choi, Youngjin Choi, Jaeyun Kim*
Muscle cell alignment plays an essential key role in the development of parallelly organized myotubes and the exertion of mechanical functions. Despite remarkable advances in cell alignment, there is still a need for a simpler and more efficient method of stably aligning and supporting cells. Here, we propose magnetic assembly of alginate-coated magnetic microparticles for myoblast alignment. Applying an external magnetic field in a controlled manner followed by ionic cross-linking of adjacent alginate chains led to the formation of stable linear alignment of particles in centimeter-scale even after the removal of the magnetic field. Based on this anisotropic alignment of bundles consisting of magnetic particles with further modification of alginate with arginine-glycine-aspartic acid, myoblast alignment was successfully demonstrated in vitro. Moreover, these particles can be simply injected through a needle without extra surgery and magnetically assembled to maintain the aligned structure in vivo. This injectable material platform can provide a facile method to supply structural directionality to the cells being regenerated, especially myoblasts for muscular tissues in clinical muscle loss or injury. © 2019 American Chemical Society.