3D Microperiodic Hydrogel Scaffolds for Robust Neuronal Cultures.

Three-dimensional (3D) microperiodic scaffolds of poly(2-hydroxyethyl methacrylate) (pHEMA) have been fabricated by direct-write assembly of a photopolymerizable hydrogel ink. The ink is initially composed of physically entangled pHEMA chains dissolved in a solution of HEMA monomer, comonomer, photoinitiator and water. Upon printing 3D scaffolds of varying architecture, the ink filaments are exposed to UV light, where they are transformed into an interpenetrating hydrogel network of chemically cross-linked and physically entangled pHEMA chains. These 3D microperiodic scaffolds are rendered growth compliant for primary rat hippocampal neurons by absorption of polylysine. Neuronal cells thrive on these scaffolds, forming differentiated, intricately branched networks. Confocal laser scanning microscopy reveals that both cell distribution and extent of neuronal process alignment depend upon scaffold architecture. This work provides an important step forward in the creation of suitable platforms for in vitro study of sensitive cell types.

通过可光聚合水凝胶墨水的直写组装，制备了聚（甲基丙烯酸2 - 羟乙酯）（pHEMA）的三维（3D）微周期支架。该墨水最初由溶解在甲基丙烯酸2 - 羟乙酯单体、共聚单体、光引发剂和水的溶液中的物理缠结的pHEMA链组成。在打印出不同结构的3D支架时，墨丝暴露于紫外光下，在此过程中它们转变为化学交联且物理缠结的pHEMA链的互穿水凝胶网络。通过吸附多聚赖氨酸，这些3D微周期支架变得适合原代大鼠海马神经元生长。神经元细胞在这些支架上茁壮成长，形成分化的、错综复杂的分支网络。共聚焦激光扫描显微镜显示，细胞分布和神经元突起排列程度均取决于支架结构。这项工作在为敏感细胞类型的体外研究创建合适平台方面向前迈出了重要的一步。