Study on negative ion-implanted biomaterials to induce vascular endothelial cells and neural cells

本研究的目的是研究和开发负离子注入材料，以辅助和诱导修复和再生损伤的生物组织，如血管和神经系统。用中性和电离化碱性轰击型重负离子源(NIABNIS)在5~30keV的较低离子能量下，将银负离子(Ag2-)注入聚苯乙烯(PS)和组织培养聚苯乙烯(TCPS)，剂量分别为10^lt；14和10^lt；16~(-2)。用二次离子质谱仪(SIMS)、X射线光电子能谱(XPS)、傅立叶变换红外光谱(FTIR)、显微拉曼光谱和接触角测量等手段对注入银的PS表面进行了研究。银离子注入后，聚苯乙烯表面发生降解，亲水性增强，血管内皮细胞密度在注入银离子后明显降低，而注入银离子的聚苯乙烯表面细胞密度明显高于未注入银离子的聚苯乙烯。此外，还观察到细胞在植入银离子的PS区被诱导，并平行排列在与植入银离子的TCPS区相邻的TCPS区上，呈条状排列。观察到小鼠来源的神经细胞以与血管内皮细胞相同的方式附着在银离子植入的PS区。此外，在银离子注入的PS区，还观察到突起的生长。C^-、Cu^-、Ag+注入的PS和TCPS对神经细胞的培养无显著差异，但对细胞的影响机制尚不清楚，有待进一步研究。

The purpose of this research is to study and develop on negative ion-implanted materials which assist and induce to repair and regenerate wounded biological tissues, such as vascular blood vessels and neural systems. Silver negative ions (Ag^-) were chosen first to be implanted to polystyrene (PS) and tissue culture polystyrene (TCPS) by using neutral and ionized alkaline bombardment-type heavy negative ion sources (NIABNIS) in doses of 10^<14> to 10^<16> ions "Jm^<-2> at relatively low ion energies of 5-30 keV.The surface property and biocompatability of Ag^--implanted TCPS and PS were investigated. Surfaces of Ag^--implanted PS were studied by means of secondary ion mass spectrometry (SIMS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and micro-Raman spectroscopy, and contact angle measurement. As a result of Ag^--implantation, the polystyrene surfaces underwent degradation, thereby becoming more hydrophilic.The cell density of vascular endothelial cells (HUVEC) was observed to decrease remarkably on Ag^--implanted TCPS, compared with that on TCPS, while the cell density was observed to increase extremely on Ag^--implanted PS than on the untreated PS region. In addition, the cells were observed to be induced on Ag^--implanted PS region from PS region, and to be lined up in parallel on the TCPS region contiguous to the Ag^--implanted TCPS region in the shape of stripe. Murine-derived neural cells were observed to settle on the Ag^--implanted PS region in the manner same as vascular endothelial cells. In addition, the neurite outgrowth was also observed to develop specifically on the Ag^--implanted PS region. There was no significant difference for the culture of neural cells among on C^-, Cu^-, and Ag^--implanted PS and TCPS, although the mechanism for effects on cells is unclear and the further study is necessary.