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Hydrogels are engineered with biochemical and biophysical signals to recreate aspects of the native microenvironment and to control cellular functions such as differentiation and matrix deposition. This deposited matrix accumulates within the pericellular space and likely affects the interactions between encapsulated cells and the engineered hydrogel; however, there has been little work to study the spatiotemporal evolution of matrix at this interface. To address this, metabolic labeling is employed to separately visualize the temporal and spatial positioning of nascent proteins and proteoglycans deposited by chondrocytes. Within covalently crosslinked hyaluronic acid hydrogels, chondrocytes deposit nascent proteins and proteoglycans in the pericellular space within 1 d after encapsulation, and proteoglycans extend further into the hydrogel. The accumulation of this matrix, as measured by an increase in matrix thickness during culture, depends on the initial hydrogel crosslink density with decreased thicknesses for more crosslinked hydrogels. Encapsulated fluorescent beads are used to monitor the hydrogel location and indicate that the emerging nascent matrix physically displaces the hydrogel from the cell membrane with extended culture. These findings suggest that secreted matrix increasingly masks the presentation of engineered hydrogel cues and may have implications for the design of hydrogels in tissue engineering and regenerative medicine.
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Hydrogel-Textile Composites: Actuators for Shape-Changing Interfaces
The current work examines interactions that are enabled when depositing a human-safe hydrogel onto textile substrates. These hydrogel-textile composites are water-responsive, supporting reversible actuation. To enable these interactions, we describe a fabrication process using a consumer-grade 3D printer. We show how different combinations of printed hydrogel patterns and textiles create a rich actuator design space. Finally, we show an application of this approach and discuss opportunities for future work.
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- Award ID(s):
- 1718651
- PAR ID:
- 10191366
- Date Published:
- Journal Name:
- Extended Abstracts of the 2020 CHI Conference on Human Factors in Computing Systems
- Page Range / eLocation ID:
- 1 to 9
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Conference Paper:
- https://doi.org/10.1145/3334480.3382788
