Bioinspired Helical Micromotors as Dynamic Cell Microcarriers.

Micromotors have exhibit great potential in multidiscplinary nanotechnology, environmental science, and especially biomedical engineering due to their advantages over controllable motion, long lifetime and biocompatibility. Marvelous effort focusing on endowing micromotors with novel characteristics and functionalities to promote their applications in biomedical engineering has been taken in recent years. Here, inspired by the flagellar motion of Escherichia coli, we present helical micromotors as dynamic cell microcarriers by using a simple microfluidic spinning technology. The morphologies of micromotors can be easily tailored because of the highly controllable and feasible fabrication process including microfluidic generation and manual dicing. Benefiting from the biocompatibility of the materials, the resultant helical micromotors could be ideal cell microcarriers that are suitable for cell seeding and further cultivation; the magnetic nanoparticle encapsulation imparts the helical micromotors with kinetic characteristics in response to mobile magnetic fields. Thus, the helical micromotors could be taken as dynamic cell culture blocks and be further assembled to complex geometrical structures. The constructed structures out of cell seeded micromotors could find their practical potential in biomedical applications as the stack-shaped assay embedded in the hydrogel may be used for tissue repairing and the tube-appeared assembly for resembled vascular structure in the microchannel for organ-on-a-chip study or blood vessel regeneration. These features manifest the possibility to broaden the biomedical application scope for micromotors.