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Over the past two decades, there has been a growing body of work on wireless devices that can operate on the length scales of biological cells and even smaller. A class of these devices receiving increasing attention are referred to as bio-hybrid actuators: tools that integrate biological cells or subcellular parts with synthetic or inorganic components. These devices are commonly controlled through magnetic manipulation as magnetic fields and gradients can be generated with a high level of control. Recent work has demonstrated that magnetic bio-hybrid actuators can address common challenges in small scale fabrication, control, and localization. Additionally, it is becoming apparent that these magnetically driven bio-hybrid devices can display high efficiency and, in many cases, have the potential for self-repair and even self-replication. Combining these properties with magnetically driven forces and torques, which can be transmitted over significant distances, can be highly controlled, and are biologically safe, gives magnetic bio-hybrid actuators significant advantages over other classes of small scale actuators. In this review, we describe the theory and mechanisms required for magnetic actuation, classify bio-hybrid actuators by their diverse organic components, and discuss their current limitations. Insights into the future of coupling cells and cell-derived components with magnetic materials to fabricate multi-functional actuators are also provided.
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Extrusion-based 3D (Bio)Printed Tissue Engineering Scaffolds: Process−Structure−Quality Relationships
Biological additive manufacturing (Bio-AM) has emerged as a promising approach for the fabrication of biological scaffolds with nano- to microscale resolutions and biomimetic architectures beneficial to tissue engineering applications. However, Bio-AM processes tend to introduce flaws in the construct during fabrication. These flaws can be traced to material nonhomogeneity, suboptimal processing parameters, changes in the (bio)-printing environment (such as nozzle clogs), and poor construct design, all with significant contributions to the alteration of a scaffold’s mechanical properties. In addition, the biological response of endogenous and exogenous cells interacting with the defective scaffolds could become unpredictable. In his Review, we first described extrusion-based Bio-AM. We highlighted the salient architectural and mechanotransduction parameters affecting the response of cells interfaced with the scaffolds. The process phenomena leading to defect formation and some of the tools for defect detection are reviewed. The limitations of the existing developments and the directions that the field should grow in to overcome said limitations are discussed.
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- Award ID(s):
- 1739696
- PAR ID:
- 10291863
- Date Published:
- Journal Name:
- ACS biomaterials science engineering
- ISSN:
- 2373-9878
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/https://doi.org/10.1021/acsbiomaterials.1c00598
