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Electrical stimulation of existing three-dimensional bioprinted tissues to alter tissue activities is typically associated with wired delivery, invasive electrode placement, and potential cell damage, minimizing its efficacy in cardiac modulation. Here, we report an optoelectronically active scaffold based on printed gelatin methacryloyl embedded with micro-solar cells, seeded with cardiomyocytes to form light-stimulable tissues. This enables untethered, noninvasive, and damage-free optoelectronic stimulation–induced modulation of cardiac beating behaviors without needing wires or genetic modifications to the tissue solely with light. Pulsed light stimulation of human cardiomyocytes showed that the optoelectronically active scaffold could increase their beating rates (>40%), maintain high cell viability under light stimulation (>96%), and negligibly affect the electrocardiogram morphology. The seeded scaffolds, termed optoelectronically active tissues, were able to successfully accelerate heart beating in vivo in rats. Our work demonstrates a viable wireless, printable, and optically controllable tissue, suggesting a transformative step in future therapy of electrically active tissues/organs.
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Effect of Electrical Stimulation on Spontaneously Beating Dynamics of Cardiac Tissues: An Analysis Using Digital Image Correlation
Abstract Electrical pacing/stimulations (EP) have been widely adopted to promote the maturation of hiPSC‐derived cardiomyocytes. However, there is a debate about their functions and effectiveness due to non‐optimized pacing conditions. Here, the effectiveness of EP (13 V cm−1, 2 ms in width, and 5 Hz frequency) on cardiac tissue beating mechanics are analyzed using digital image correlation (DIC). The cardiac tissues with and without EP at tissue culture time from day 2 to 11 (D2–D11) are characterized and compared. The results indicate EP decreased cardiac beating motion for ≈2–15 times, promote synchronization, and improve ion handling. A positive correlation between cardiac beating mechanics and ion handling is observed. DIC method can optimize chemical, mechanical, and electrical stimulation, which could help create more mature cardiac tissues.
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- Award ID(s):
- 1647837
- PAR ID:
- 10362267
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 6
- Issue:
- 12
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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