Carbon-nanotube-embedded hydrogel sheets for engineering cardiac constructs and bioactuators.
We engineered functional cardiac patches by seeding neonatal rat cardiomyocytes onto carbon nanotube (CNT)-incorporated photo-cross-linkable gelatin methacrylate (GelMA) hydrogels. The resulting cardiac constructs showed excellent mechanical integrity and advanced electrophysiological functions. Specifically, myocardial tissues cultured on 50 μm thick CNT-GelMA showed 3 times higher spontaneous synchronous beating rates and 85% lower excitation threshold, compared to those cultured on pristine GelMA hydrogels. Our results indicate that the electrically conductive and nanofibrous networks formed by CNTs within a porous gelatin framework are the key characteristics of CNT-GelMA leading to improved cardiac cell adhesion, organization, and cell-cell coupling. Centimeter-scale patches were released from glass substrates to form 3D biohybrid actuators, which showed controllable linear cyclic contraction/extension, pumping, and swimming actuations. In addition, we demonstrate for the first time that cardiac tissues cultured on CNT-GelMA resist damage by a model cardiac inhibitor as well as a cytotoxic compound. Therefore, incorporation of CNTs into gelatin, and potentially other biomaterials, could be useful in creating multifunctional cardiac scaffolds for both therapeutic purposes and in vitro studies. These hybrid materials could also be used for neuron and other muscle cells to create tissue constructs with improved organization, electroactivity, and mechanical integrity.
Center for Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 65 Landsdowne Street, Cambridge, Massachusetts 02139, United States.
Su Ryon
SR
Shin
Sung Mi
SM
Jung
Momen
M
Zalabany
Keekyoung
K
Kim
Pinar
P
Zorlutuna
Sang Bok
SB
Kim
Mehdi
M
Nikkhah
Masoud
M
Khabiry
Mohamed
M
Azize
Jing
J
Kong
Kai-Tak
KT
Wan
Tomas
T
Palacios
Mehmet R
MR
Dokmeci
Hojae
H
Bae
Xiaowu Shirley
XS
Tang
Ali
A
Khademhosseini
D000818:Animals; D040761:Biomimetic Materials; D005109:Extracellular Matrix / Q000378:metabolism; D005780:Gelatin / Q000737:chemistry; D020100:Hydrogels; D009206:Myocardium / Q000166:cytology* / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000166:cytology / Q000378:metabolism; D036103:Nanotechnology; D037742:Nanotubes, Carbon; D051381:Rats; D023822:Tissue Engineering; D054457:Tissue Scaffolds / Q000737:chemistry
D020100:Hydrogels; D037742:Nanotubes, Carbon; D005780:Gelatin