Ion Beam Processing of Polymeric Biomaterials

1. 在5 ~ 30 keV的能量下对聚苯乙烯（PS）、聚二甲基硅氧烷（PDMS）和聚乳酸（PLA）等聚合物进行负离子或正离子注入，用XPS研究了其表面纯水的接触角、引入氧原子的数量和原子键态。几乎在所有情况下，离子束处理的表面比未处理的表面显示出更低的接触角。而低能注入PLA的接触角较高。离子注入降低接触角的原因是形成带有C-O和/或C=O键的官能团2。离子束处理的聚合物表面和选择性细胞附着性能的生物学评价将具有NGF活性的PC-12h（大鼠肾上腺嗜铬细胞瘤）神经细胞培养在离子束处理的PS、PDMS和PLA聚合物表面。在含血清的高糖培养基中，细胞仅在离子束植入物上表现出选择性附着特性。此外，在无血清培养基中，细胞在仅离子注入区域表现出选择性的神经突出延伸。因此，我们实现了神经细胞在聚合物表面附着特性的控制。对于PLA， 5 keV左右的低能负离子注入使细胞的附着性降低，低剂量30keV的高能量负离子束注入使细胞的附着性增强。聚合物表面的图案化负离子束处理和神经元网络在自旋涂覆聚苯乙烯薄膜上的人工形成聚合物表面是银、铜和碳的负离子束，通过带有许多几μm宽的缝的图案化掩模处理。在这种微模式下，不仅在PS、PDMS和PLA等块体材料上，而且在自旋涂覆的聚苯乙烯薄膜上，都实现了细胞的选择性附着和选择性突出延伸，从而在PS薄膜上形成了人工设计的神经细胞网络。因此，我们开发了离子束处理技术用于生物医学聚合物的表面修饰，并实现了神经细胞附着和突出膨胀等生物相容性的控制。通过这种处理，我们制造了一个人工设计的神经元网络。少

1. Physical Evaluation of Ion Beam Treated Polymer Surfaces and Hydrophilic SurfacePolymers such as polystyrene (PS), polydimethylsiloxane (PDMS) and poly-lactic-acid (PLA) were implanted with negative or positive ions at energy in 5-30 keV, and their surfaces are investigated about contact angle of pure water, and about amount of introduced oxygen atoms and atomic bonding states by XPS.In almost all case, ion beam treated surfaces showed lower contact angle than untreated surfaces. But low energy implanted PLA showed higher contact angle. The lowering contact angle by ion implantation was found to be resulted by forming functional groups with C-O and/or C=O bonds2. Biological Evaluation of Ion Beam Treated Polymer Surfaces and Selective Cell Attachment PropertiesNerve cells of PC-12h (rat adrenal phechromocytoma) with NGF active property were cultured on the ion beam treated polymer surfaces of PS, PDMS, and PLA.The cells showed selective attachment properties on only ion beam implant … More ed region in a high glucose medium with serum. Besides, the cells showed selective nerve protrusion extension over only ion implanted region in serum-free medium. Thus, we achieved control of nerve cell attachment properties on polymer surface. For PLA, cell attachment property was removed by low energy negative ion implantation about 5 keV, and cell attachment property was enhanced by negative ion beam implantation at a high energy of 30keV with a low dose.3. Patterningly Negative Ion Beam Processing of Polymer Surfaces and Artificial Formation of Neuron Network on Spin-coated Polystyrene FilmsPolymer surfaces were silver, copper, and carbon negative ion beam treated through a patterning mask with many slits of several μm in width. In such micro-pattern, selective cell attachment and selective protrusion extension properties were achieved not only on bulk materials of PS, PDMS and PLA but also on spin-coated polystyrene thin films Thus, we formed artificially designed nerve cell network on PS films.Thus, we developed ion beam processing technique for biomedical polymer surface modification and achieved control of biocompatibility such as nerve cell attachment and protrusion expansion properties. By this processing, we made an artificially designed neuron network. Less