School of Dentistry, The University of Queensland, Oral Health Centre, 288 Herston Rd, QLD 4006, Australia. Department of Engineering Materials and Mechanical Design, Faculty of Engineering, South Valley University, Qena 83523, Egypt.
Biofabrication. 2018 Nov 1;11(1):015006. doi: 10.1088/1758-5090/aae421.
Nanoscale fibers mimicking the extracellular matrix of natural tissue can be produced by conventional electrospinning, but this approach results in two-dimensional thin dense fibrous mats which can hinder effective cell infiltration. The aim of the present study was to design a thick, three-dimensional (3D) cylindrical scaffold with an open pore structure assembled from short polycaprolactone (PCL) fibers using a facile airbrushing approach. In addition, magnesium particles were incorporated into the PCL solution to both enhance the mechanical properties of the scaffold and stimulate cellular activity following cell seeding. Separated short composite airbrushed fibers were assembled into a 3D cylindrical structure by cold-press molding and thermal cross-linking. The microstructure, chemical composition, porosity and thermal properties were subsequently investigated, along with changes in mechanical performance following immersion in PBS for 60 d. The results showed that the assembled 3D fibrous 10 mm thick cylindrical matrix had an interconnected fibrous network structure with 31.5%-60% porosity. Encapsulation of the Mg particles into the 3D assembled fibrous scaffold enhanced the mechanical properties of the plain PCL scaffolds. The results also demonstrated controlled release of Mg ions into the PBS media for up to 60 d, as evaluated by changes in Mg ion concentration and pH of the media. In addition, the 3D fibrous assembled matrix was shown to support human osteoblast-like cell adhesion, proliferation and penetration. The results suggest that this novel fabrication method of biodegradable thick 3D scaffolds with an open pore structure is promising for the production of a new generation of 3D scaffolds for tissue regeneration applications.
纳米纤维模仿天然组织的细胞外基质可以通过传统的静电纺丝来生产，但这种方法会得到二维的、致密的纤维垫，从而阻碍细胞的有效渗透。本研究的目的是设计一种由短聚己内酯（PCL）纤维组成的、具有开放孔结构的厚的三维（3D）圆柱形支架，采用简单的喷涂方法。此外，将镁颗粒掺入 PCL 溶液中，以增强支架的机械性能，并在细胞接种后刺激细胞活性。分离的短复合喷涂纤维通过冷压成型和热交联组装成 3D 圆柱形结构。随后研究了微观结构、化学成分、孔隙率和热性能，并在 PBS 中浸泡 60 天后机械性能的变化。结果表明，组装的 3D 纤维状、10 毫米厚的圆柱形基质具有相互连接的纤维网络结构，孔隙率为 31.5%-60%。将 Mg 颗粒包埋在 3D 组装纤维支架中，增强了纯 PCL 支架的机械性能。结果还表明，在 PBS 介质中可控制释放 Mg 离子长达 60 天，这可以通过 Mg 离子浓度和介质 pH 值的变化来评估。此外，3D 纤维组装基质被证明可以支持人成骨样细胞的黏附、增殖和渗透。结果表明，这种具有开放孔结构的生物可降解厚 3D 支架的新型制造方法有望用于生产新一代用于组织再生应用的 3D 支架。
