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Abstract The mechanical function of the myocardium is defined by cardiomyocyte contractility and the biomechanics of the extracellular matrix (ECM). Understanding this relationship remains an important unmet challenge due to limitations in existing approaches for engineering myocardial tissue. Here, they established arrays of cardiac microtissues with tunable mechanics and architecture by integrating ECM‐mimetic synthetic, fiber matrices, and induced pluripotent stem cell‐derived cardiomyocytes (iPSC‐CMs), enabling real‐time contractility readouts, in‐depth structural assessment, and tissue‐specific computational modeling. They found that the stiffness and alignment of matrix fibers distinctly affect the structural development and contractile function of pure iPSC‐CM tissues. Further examination into the impact of fibrous matrix stiffness enabled by computational models and quantitative immunofluorescence implicates cell‐ECM interactions in myofibril assembly, myofibril maturation, and notably costamere assembly, which correlates with improved contractile function of tissues. These results highlight how iPSC‐CM tissue models with controllable architecture and mechanics can elucidate mechanisms of tissue maturation and disease.
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Electronic‐ECM: A Permeable Microporous Elastomer for an Advanced Bio‐Integrated Continuous Sensing Platform
Abstract Tissue interfaced electronics have become promising candidates for transcending beyond conventional diagnostic technology, enabling chronic, quantitative health monitoring possibilities; however, these systems have primarily relied on impenetrable materials that contribute to the mechanical and physical mismatch of bioelectronic interfaces. Inspired by the soft mechanics and physical architecture of the epidermal extracellular matrix, this study presents a 3D microporous, fibrous mesh of polydimethylsiloxane for epidermal electronics. The resulting elastic microfiber mat, exhibits a minimal mechanical footprint with analogous viscoelastic behavior, cytocompatibility, and biofluid‐permeable interface capable of small molecule, gas, and transdermal water diffusion. Electrocardiography electrodes heterogeneously integrate within the synthetic electronic‐extracellular matrix (e‐ECM) membrane and achieve chronic high resolution biopotential monitoring during typically debilitating environments (e.g., vigorous sweating) for conventional bioelectronics. The e‐ECM platform provides a substrate template for open‐mesh electronics, enabling advanced implementations in long‐term quantitative analysis monitoring for wearable and implantable devices.
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- Award ID(s):
- 2020486
- PAR ID:
- 10457918
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 5
- Issue:
- 7
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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