Zheng Ting, Pour Shahid Saeed Abadi Parisa, Seo Jungmok, Cha Byung-Hyun, Miccoli Beatrice, Li Yi-Chen, Park Kijun, Park Sunghyun, Choi Seon-Jin, Bayaniahangar Rasoul, Zhang Dongxing, Lee Soo-Hong, Lee Chang-Kee, Khademhosseini Ali, Shin Su Ryon
Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital , Harvard Medical School , Cambridge , Massachusetts 02139 , United States.
Harvard-MIT Division of Health Sciences and Technology , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States.
ACS Appl Mater Interfaces. 2019 Jun 12;11(23):20615-20627. doi: 10.1021/acsami.9b02927. Epub 2019 May 22.
Biocompatible, electrically conductive microfibers with superior mechanical properties have received a great attention due to their potential applications in various biomedical applications such as implantable medical devices, biosensors, artificial muscles, and microactuators. Here, we developed an electrically conductive and mechanically stable carbon nanotube-based microactuator with a low degradability that makes it usable for an implantable device in the body or biological environments. The microfiber was composed of hyaluronic acid (HA) hydrogel and single-wall carbon nanotubes (SWCNTs) (HA/SWCNT). HA hydrogel acts as biosurfactant and ion-conducting binder to improve the dispersion of SWCNTs resulting in enhanced electrical and mechanical properties of the hybrid microfiber. In addition, HA was crosslinked to prevent the leaking of the nanotubes from the composite. Crosslinking of HA hydrogel significantly enhances Young's modulus, the failure strain, the toughness, the stability of the electrical conductivity, and the resistance to biodegradation and creep of hybrid microfibers. The obtained crosslinked HA/SWCNT hybrid microfibers show an excellent capacitance and actuation behavior under mechanical loading with a low potential of ±1 V in a biological environment. Furthermore, the HA/SWCNT microfibers exhibit an excellent in vitro viability. Finally, the biocompatibility is shown through the resolution of an early inflammatory response in less than 3 weeks after the implantation of the microfibers in the subcutaneous tissue of mice.
具有优异机械性能的生物相容性导电微纤维因其在各种生物医学应用中的潜在应用而备受关注，这些应用包括可植入医疗设备、生物传感器、人工肌肉和微致动器等。在此，我们开发了一种基于碳纳米管的导电且机械稳定的微致动器，其降解性低，可用于体内或生物环境中的可植入设备。该微纤维由透明质酸（HA）水凝胶和单壁碳纳米管（SWCNTs）（HA/SWCNT）组成。HA水凝胶充当生物表面活性剂和离子传导粘合剂，以改善SWCNTs的分散性，从而提高混合微纤维的电学和机械性能。此外，HA被交联以防止纳米管从复合材料中泄漏。HA水凝胶的交联显著提高了混合微纤维的杨氏模量、断裂应变、韧性、电导率稳定性以及抗生物降解和抗蠕变能力。所获得的交联HA/SWCNT混合微纤维在生物环境中±1 V的低电位下机械加载时表现出优异的电容和驱动行为。此外，HA/SWCNT微纤维表现出优异的体外活力。最后，通过在将微纤维植入小鼠皮下组织后不到3周内早期炎症反应的消退，证明了其生物相容性。
