Sønstevold Linda, Koza Paulina, Czerkies Maciej, Andreassen Erik, McMahon Paul, Vereshchagina Elizaveta
Department of Smart Sensors and Microsystems, SINTEF Digital, Gaustadalléen 23C, 0373 Oslo, Norway.
Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawińskiego St. 5B, 02-106 Warsaw, Poland.
Micromachines (Basel). 2024 Jul 10;15(7):898. doi: 10.3390/mi15070898.
With the rapid development and commercial interest in the organ-on-a-chip (OoC) field, there is a need for materials addressing key experimental demands and enabling both prototyping and large-scale production. Here, we utilized the gas-permeable, thermoplastic material polymethylpentene (PMP). Three methods were tested to prototype transparent PMP films suitable for transmission light microscopy: hot-press molding, extrusion, and polishing of a commercial, hazy extruded film. The transparent films (thickness 20, 125, 133, 356, and 653 µm) were assembled as the cell-adhering layer in sealed culture chamber devices, to assess resulting oxygen concentration after 4 days of A549 cell culture (cancerous lung epithelial cells). Oxygen concentrations stabilized between 15.6% and 11.6%, where the thicker the film, the lower the oxygen concentration. Cell adherence, proliferation, and viability were comparable to glass for all PMP films (coated with poly-L-lysine), and transparency was adequate for transmission light microscopy of adherent cells. Hot-press molding was concluded as the preferred film prototyping method, due to excellent and reproducible film transparency, the possibility to easily vary film thickness, and the equipment being commonly available. The molecular orientation in the PMP films was characterized by IR dichroism. As expected, the extruded films showed clear orientation, but a novel result was that hot-press molding may also induce some orientation. It has been reported that orientation affects the permeability, but with the films in this study, we conclude that the orientation is not a critical factor. With the obtained results, we find it likely that OoC models with relevant in vivo oxygen concentrations may be facilitated by PMP. Combined with established large-scale production methods for thermoplastics, we foresee a useful role for PMP within the OoC field.
随着芯片器官（OoC）领域的迅速发展和商业兴趣的增加，需要能够满足关键实验要求并支持原型制作和大规模生产的材料。在此，我们使用了透气的热塑性材料聚甲基戊烯（PMP）。测试了三种方法来制作适用于透射光显微镜的透明PMP薄膜原型：热压成型、挤出以及对商用的模糊挤出薄膜进行抛光。将透明薄膜（厚度分别为20、125、133、356和653 µm）组装为密封培养室装置中的细胞粘附层，以评估A549细胞（肺癌细胞系）培养4天后的氧浓度。氧浓度稳定在15.6%至11.6%之间，薄膜越厚，氧浓度越低。对于所有PMP薄膜（涂有聚-L-赖氨酸），细胞粘附、增殖和活力与玻璃相当，并且透明度足以对贴壁细胞进行透射光显微镜观察。由于薄膜透明度极佳且可重复、易于改变薄膜厚度且设备常见，热压成型被确定为首选的薄膜原型制作方法。通过红外二向色性对PMP薄膜中的分子取向进行了表征。正如预期的那样，挤出薄膜显示出明显的取向，但一个新的结果是热压成型也可能诱导一些取向。据报道，取向会影响渗透性，但对于本研究中的薄膜，我们得出结论，取向不是一个关键因素。基于所获得的结果，我们发现PMP可能有助于构建具有体内相关氧浓度的OoC模型。结合已有的热塑性塑料大规模生产方法，我们预计PMP在OoC领域将发挥有益作用。
