Chen Chengpeng, Townsend Alexandra D, Sell Scott A, Martin R Scott
Department of Chemistry, Saint Louis University.
Department of Biomedical Engineering, Saint Louis University.
Anal Methods. 2017 Jun 14;9(22):3274-3283. doi: 10.1039/C7AY00756F. Epub 2017 Apr 21.
Polymer nano/micro fibers have found many applications including 3D cell culture and the creation of wound dressings. The fibers can be produced by a variety of techniques that include electrospinning, the primary disadvantage of which include the requirement for a high voltage supply (which may cause issues such as polymer denaturation) and lack of portability. More recently, solution blow spinning, where a high velocity sheath gas is used instead of high voltage, has been used to generate polymer fibers. In this work, we used blow spinning to create nano/microfibers for microchip-based 3D cell culture. First, we thoroughly investigated fiber generation from a 3D printed gas sheath device using two polymers that are amenable to cell culture (polycaprolactone, PCL and polystyrene, PS) as well as the parameters that can affect PCL and PS fiber quality. Using the 3D printed sheath device, it was found that the pressure of the sheath N and the concentration of polymer solutions determine if fibers can be produced as well as the resulting fiber morphology. In addition, we showed how these fibers can be used for 3D cell culture by directly depositing PCL fibers in petri dishes and well plates. It is shown the fibers have good compatibility with RAW 264.7 macrophages and the PCL fiber scaffold can be as thick as 178 ± 14 μm. PCL fibers created from solution blow spinning (with the 3D printed sheath device) were then integrated with a microfluidic device for the first time to fabricate a 3D cell culture scaffold with a flow component. After culturing and stimulating macrophages on the fluidic device, it was found that the integrated 3D fibrous scaffold is a better mimic of the extracellular matrix (as opposed to a flat, 2D substrate), with enhanced nitrite accumulation (product of nitric oxide release) from macrophages stimulated with lipopolysaccharide. PS fibers were also made and integrated in a microfluidic device for 3D culture of endothelial cells, which stayed viable for at least 72 hours (48 hours under the flowing conditions). This approach will be useful for future studies involving more realistic microchip-based culture models for studying cell-to-cell communication.
聚合物纳米/微纤维已在许多领域得到应用，包括3D细胞培养和伤口敷料的制作。这些纤维可通过多种技术生产，其中包括静电纺丝，其主要缺点包括需要高压电源（这可能会导致聚合物变性等问题）以及缺乏便携性。最近，溶液吹纺技术被用于生产聚合物纤维，该技术使用高速鞘气代替高压。在这项工作中，我们使用吹纺技术制造用于基于微芯片的3D细胞培养的纳米/微纤维。首先，我们使用两种适用于细胞培养的聚合物（聚己内酯，PCL和聚苯乙烯，PS）以及可能影响PCL和PS纤维质量的参数，对3D打印气体鞘装置产生的纤维进行了深入研究。使用3D打印鞘装置发现，鞘气N的压力和聚合物溶液的浓度决定了是否能够生产纤维以及所得纤维的形态。此外，我们展示了如何通过将PCL纤维直接沉积在培养皿和孔板中来将这些纤维用于3D细胞培养。结果表明，这些纤维与RAW 264.7巨噬细胞具有良好的相容性，并且PCL纤维支架的厚度可达178±14μm。然后，首次将溶液吹纺（使用3D打印鞘装置）产生的PCL纤维与微流控装置集成，以制造具有流动组件的3D细胞培养支架。在流体装置上培养和刺激巨噬细胞后，发现集成的3D纤维支架更能模拟细胞外基质（与平坦的2D基质相反），脂多糖刺激的巨噬细胞释放的亚硝酸盐积累增加（一氧化氮释放的产物）。还制备了PS纤维并将其集成到用于内皮细胞3D培养的微流控装置中，内皮细胞在至少72小时内保持存活（在流动条件下为48小时）。这种方法将有助于未来涉及更逼真的基于微芯片的培养模型来研究细胞间通讯的研究。
