Park Jaeil, Nguyen Thi Thuy Chau, Lee Su-Jin, Wang Sungrok, Heo Dongmi, Kang Dong-Hee, Tipan-Quishpe Alexander, Lee Won-June, Lee Jongwon, Yang Sung Yun, Yoon Myung-Han
School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-Ro, Buk-Gu, Gwangju, 61005, Republic of Korea.
Department of Polymer Science and Engineering, Graduate School of Chungnam National University, 99 Daehak-Ro, Yuseong-Gu, Daejeon, 34134, Republic of Korea.
Biomater Res. 2023 Mar 13;27(1):19. doi: 10.1186/s40824-023-00344-3.
Hydrogels have been widely used in many research fields owing to optical transparency, good biocompatibility, tunable mechanical properties, etc. Unlike typical hydrogels in the form of an unstructured bulk material, we developed aqueous dispersions of fiber-shaped hydrogel structures with high stability under ambient conditions and their application to various types of transparent soft cell culture interfaces with anisotropic nanoscale topography.
Nanofibers based on the polyvinyl alcohol and polyacrylic acid mixture were prepared by electrospinning and hydrogelified to nano-fibrous hydrogels (nFHs) after thermal crosslinking and sulfuric acid treatment. By modifying various material surfaces with positively-charged polymers, negatively-charged superabsorbent nFHs could be selectively patterned by employing micro-contact printing or horizontally aligned by applying shear force with a wired bar coater.
The angular distribution of bar-coated nFHs was dramatically reduced to ± 20° along the applied shear direction unlike the drop-coated nFHs which exhibit random orientations. Next, various types of cells were cultured on top of transparent soft nFHs which showed good viability and attachment while their behaviors could be easily monitored by both upright and inverted optical microscopy. Particularly, neuronal lineage cells such as PC 12 cells and embryonic hippocampal neurons showed highly stretched morphology along the overall fiber orientation with aspect ratios ranging from 1 to 14. Furthermore, the resultant neurite outgrowth and migration behaviors could be effectively controlled by the horizontal orientation and the three-dimensional arrangement of underlying nFHs, respectively.
We expect that surface modifications with transparent soft nFHs will be beneficial for various biological/biomedical studies such as fundamental cellular studies, neuronal/stem cell and/or organoid cultures, implantable probe/device coatings, etc.
水凝胶因其光学透明性、良好的生物相容性、可调的机械性能等，已在许多研究领域中得到广泛应用。与无结构块状材料形式的典型水凝胶不同，我们开发了在环境条件下具有高稳定性的纤维状水凝胶结构的水分散体，并将其应用于具有各向异性纳米级形貌的各种类型透明软细胞培养界面。
通过静电纺丝制备基于聚乙烯醇和聚丙烯酸混合物的纳米纤维，并在热交联和硫酸处理后水凝胶化为纳米纤维水凝胶（nFHs）。通过用带正电荷的聚合物修饰各种材料表面，带负电荷的超吸收性nFHs可以通过微接触印刷进行选择性图案化，或通过使用线棒涂布机施加剪切力进行水平排列。
与呈现随机取向的滴涂nFHs不同，线棒涂布的nFHs的角分布沿施加的剪切方向急剧减小至±20°。接下来，在透明软nFHs上培养各种类型的细胞，这些细胞显示出良好的活力和附着性，同时通过正立和倒置光学显微镜都可以轻松监测它们的行为。特别是，诸如PC 12细胞和胚胎海马神经元等神经谱系细胞沿整体纤维取向呈现高度伸展的形态，纵横比范围为1至14。此外，由此产生的神经突生长和迁移行为可以分别通过底层nFHs的水平取向和三维排列得到有效控制。
我们期望用透明软nFHs进行表面修饰将有利于各种生物学/生物医学研究，如基础细胞研究、神经元/干细胞和/或类器官培养、可植入探针/装置涂层等。
