The brain is one of the most important and complicated organs, but it is delicate and therefore needs to be protected from external forces. This makes the pecking behavior of the Woodpecker so impressive, as they are not known to sustain any brain injury due to their anatomical adaptations (a specialized beak, skull bone, and hyoid bone). However, the relationship between the morphology of the woodpecker head and its mechanical function against damage from daily pecking habits remains an open question. Aided by recent technical advancements, these questions can be explored by applying new materials science concepts of bioinspiration and bioexploration to identify adapted structures/materials in a design that results from millions of years of evolution. Two main features, including the beam‐like bar structure of the jugal bone acting as a main stress deflector and the high natural frequency of the skull bone of woodpeckers can teach two lessons for potential materials development as well as engineering applications: protection of a delicate internal organ occurs by redirection of the main stress pathway and a large mismatch of the natural frequencies between the skull and brain avoids resonance and reduces the overall load experienced by the brain.
Engineering functional tissues and organs remains a fundamental pursuit in bio‐fabrication. However, the accurate constitution of complex shapes and internal anatomical features of specific organs, including their intricate blood vessels and nerves, remains a significant challenge. Inspired by the Matryoshka doll, here a new method called “Intra‐Embedded Bioprinting (IEB)” is introduced building upon existing embedded bioprinting methods. a xanthan gum‐based material is used which served a dual role as both a bioprintable ink and a support bath, due to its unique shear‐thinning and self‐healing properties. IEB's capabilities in organ modeling, creating a miniaturized replica of a pancreas using a photocrosslinkable silicone composite is demonstrated. Further, a head phantom and a Matryoshka doll are 3D printed, exemplifying IEB's capability to manufacture intricate, nested structures. Toward the use case of IEB and employing an innovative coupling strategy between extrusion‐based and aspiration‐assisted bioprinting, a breast tumor model that included a central channel mimicking a blood vessel, with tumor spheroids bioprinted in proximity is developed. Validation using a clinically‐available chemotherapeutic drug illustrated its efficacy in reducing the tumor volume via perfusion over time. This method opens a new way of bioprinting enabling the creation of complex‐shaped organs with internal anatomical features.
more » « less- NSF-PAR ID:
- 10480760
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small Methods
- ISSN:
- 2366-9608
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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