Centre of Bioengineering & Nanomedicine, School of Dentistry, Division of Health Sciences, University of Otago, Dunedin, New Zealand.
Department of Chemistry, University of Otago, Dunedin, New Zealand.
Biopolymers. 2022 Apr;113(4):e23482. doi: 10.1002/bip.23482. Epub 2021 Nov 23.
Melt extrusion 3D printing has become an attractive additive manufacturing technology to construct degradable scaffolds as tissue precursors in order to create clinically relevant medical devices. Towards this end, a commonly used synthetic polyester, poly-caprolactone (PCL), was used to make scaffolds composed of different biomaterial compositions to increase bioactivity using 3D melt pneumatic extrusion technology. Varying ratios of the natural biopolymer, chitosan, or the bioceramic, β-tricalcium phosphate (TCP) were blended with PCL to fabricate support scaffolds with three-dimensional (3D) architecture for human bone-marrow derived mesenchymal stem cell (hBMSC) growth for potential bone regeneration application. In this study, basic printing requirements as well as biomaterial dynamic mechanical (DMA), elemental, and thermogravimetric (TGA) analysis results demonstrate material homogeneity as well as thermal stability. Scaffold morphology and microarchitecture were assessed using scanning electron microscopy (SEM) alongside in vitro scaffold degradation and biological characterisation. Human BMSC proliferation was assessed using fluorescence imaging, and quantitated via the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) colorimetric assay. These in vitro cell viability studies revealed that the highest chitosan concentration blend of 20% favoured the most hBMSC growth, exhibited the most swelling, and showed minimal degradation after 28 days. The 20% TCP blend had the second highest hBMSC growth, exhibited moderate swelling, and the fastest degradation rate. Overall, this study demonstrates the first direct comparison of a natural biopolymer-based, that is, chitosan, 3D melt extruded PCL composite with that of a bioceramic-based, that is, β-TCP, PCL composite and their effects on hBMSC 3D proliferation. 3D melt extruded PCL-based composite scaffolds methodology offers a straightforward way to print scaffolds with good shape fidelity, interconnected porosities and enhanced bioactivity; and demonstrates their potential use for regenerative, bone repair applications.
熔融挤出 3D 打印已成为一种有吸引力的增材制造技术，可构建可降解支架作为组织前体，以制造具有临床相关性的医疗设备。为此，通常使用合成聚酯聚己内酯（PCL），使用 3D 熔融气动挤出技术，由不同生物材料组成的支架来增加生物活性。将天然生物聚合物壳聚糖或生物陶瓷β-磷酸三钙（TCP）的不同比例与 PCL 混合，制造具有三维（3D）结构的支架，用于人骨髓间充质干细胞（hBMSC）生长，以用于潜在的骨再生应用。在这项研究中，基本打印要求以及生物材料动态力学（DMA）、元素和热重分析（TGA）分析结果表明材料均匀性和热稳定性。通过扫描电子显微镜（SEM）以及体外支架降解和生物学特性评估了支架形态和微观结构。通过荧光成像评估人 BMSC 的增殖，并通过 3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四唑溴盐（MTT）比色法定量。这些体外细胞活力研究表明，20%的最高壳聚糖浓度混合物最有利于 hBMSC 的生长，表现出最大的溶胀，并在 28 天后显示最小的降解。20%TCP 混合物具有第二高的 hBMSC 生长，表现出适度的溶胀和最快的降解速度。总体而言，这项研究首次直接比较了基于天然生物聚合物的，即壳聚糖，3D 熔融挤出的 PCL 复合材料与基于生物陶瓷的，即β-TCP，PCL 复合材料及其对 hBMSC 3D 增殖的影响。3D 熔融挤出的 PCL 基复合支架方法提供了一种简单的方法来打印具有良好形状保真度、互连孔隙率和增强生物活性的支架；并证明了它们在再生、骨修复应用中的潜在用途。
