Department of Life Science, Dongguk University, Goyang, Gyeonggi-do, 10326, Republic of Korea.
Applied Quantum Composites Research Center, Korea Institute of Science and Technology, Jeonbuk 565-905, Republic of Korea.
J Biomed Mater Res A. 2018 Jan;106(1):43-51. doi: 10.1002/jbm.a.36215. Epub 2017 Sep 23.
Graphene is a noncytotoxic monolayer platform with unique physical, chemical, and biological properties. It has been demonstrated that graphene substrate may provide a promising biocompatible scaffold for stem cell therapy. Because chemical vapor deposited graphene has a two dimensional polycrystalline structure, it is important to control the individual domain size to obtain desirable properties for nano-material. However, the biological effects mediated by differences in domain size of graphene have not yet been reported. On the basis of the control of graphene domain achieved by one-step growth (1step-G, small domain) and two-step growth (2step-G, large domain) process, we found that the neuronal differentiation of bone marrow-derived human mesenchymal stem cells (hMSCs) highly depended on the graphene domain size. The defects at the domain boundaries in 1step-G graphene was higher (×8.5) and had a relatively low (13% lower) contact angle of water droplet than 2step-G graphene, leading to enhanced cell-substrate adhesion and upregulated neuronal differentiation of hMSCs. We confirmed that the strong interactions between cells and defects at the domain boundaries in 1step-G graphene can be obtained due to their relatively high surface energy, which is stronger than interactions between cells and graphene surfaces. Our results may provide valuable information on the development of graphene-based scaffold by understanding which properties of graphene domain influence cell adhesion efficacy and stem cell differentiation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 43-51, 2018.
石墨烯是一种具有独特物理、化学和生物特性的非细胞毒性单层平台。已经证明，石墨烯基底可为干细胞治疗提供有前途的生物相容支架。由于化学气相沉积石墨烯具有二维多晶结构，因此控制单个畴尺寸以获得纳米材料的理想性质非常重要。但是，由石墨烯畴尺寸差异介导的生物学效应尚未报道。在通过一步生长（1step-G，小畴）和两步生长（2step-G，大畴）过程控制石墨烯畴的基础上，我们发现骨髓来源的人骨髓间充质干细胞（hMSC）的神经元分化高度依赖于石墨烯畴的大小。 1step-G 石墨烯中的畴界缺陷较高（×8.5），水滴的接触角相对较低（低 13％），导致细胞-基底粘附增强，hMSC 的神经元分化增强。我们证实，由于其相对较高的表面能，细胞与 1step-G 石墨烯中畴界处的缺陷之间的相互作用较强，这比细胞与石墨烯表面之间的相互作用要强。通过了解石墨烯畴的哪些性质影响细胞粘附效力和干细胞分化，我们的研究结果可为基于石墨烯的支架的发展提供有价值的信息。 ©2017Wiley Periodicals，Inc. J Biomed Mater Res Part A：106A：43-51，2018。
