导电聚合物聚吡咯/聚苯乙烯硫酸酯刺激体外神经轴突生长的生物活性及组织相容性

背景：导电聚合物的合成较具灵活性，通过改变合成条件，可以使导电聚合物表现出不同的、更适宜的表面特性。 目的：观察导电聚合物聚吡咯/聚苯乙烯硫酸酯的生物相容性以及对体外神经细胞轴突生长的刺激效应。 方法：应用电化学聚合聚吡咯/聚苯乙烯硫酸酯膜片，检测导电膜片的电化学指标；然后通过体外电刺激，分4组：电刺激组、无点刺激组、空白对照组和溶液对照组观察聚吡咯/聚苯乙烯硫酸酯对嗜铬细胞瘤细胞轴突生长的生物效应；制备聚吡咯/聚苯乙烯硫酸酯-聚乳酸-聚羟基乙酸共聚物膜片，并移植到大鼠体内，观察膜片的短期和长期炎性反应，评价其组织相容性。 结果与结论：体外细胞培养图像显示，在未接受电刺激条件下，对照组和聚吡咯/聚苯乙烯硫酸酯膜上嗜铬细胞瘤细胞贴附、分化情况相似。通过聚吡咯/聚苯乙烯硫酸酯膜基质进行电刺激实验定性观察，聚吡咯/聚苯乙烯硫酸酯膜上的细胞如处在电流环境中则可使神经轴突延伸的更长，而未接受电刺激的神经轴突长度明显短于前者。此外，接受电刺激组的细胞的铺展形态明显要好于对照组，但均未见任何细胞毒性反应。体内实验现实该膜片没有诱导出明显的炎性反应。提示，聚吡咯/聚苯乙烯硫酸酯是一种组织相容性较好的材料。

Biocompatibility and bioactivity of an electrically conducting polymer, oxidized polypyrrole/polystyrene sulfate, for stimulation of neurite outgrowth in vitro

BACKGROUND: Synthesis of conductive polymers is flexible, the conductive polymer may show different and more suitable surface properties by changing the synthesis conditions. OBJECTIVE: To investigate the biocompatibility of a conductive polymer-oxidized polypyrrole/polystyrene sulfate for stimulation of neurite outgrowth in vitro. METHODS: The polypyrrole/polystyrene sulfate film was synthesized electrochemically and tested on electrochemical characters. The experiments were observed in four groups, including electrical stimulation, non-stimulation, blank control and solution control groups. The neurite outgrowth of pheochromocytoma cell line PC 12 was evaluated after in vitro electrical stimulation. The polypyrrole/polystyrene sulfate-polylactic acid-polyglycolic acid disks were fabricated and implanted in adult male Lewis rats, to evaluate both short-term and long-term inflammatory response, as well as the histocompatibility. RESULTS AND CONCLUSION: Image analysis of in vitro culture demonstrated that PC-12 cells attached and differentiated equally well on both polypyrrole/polystyrene sulfate films and control groups. Qualitative observation of polypyrrole/polystyrene sulfate film matrix after electrical stimulation showed that, PC-12 cells cultured on polypyrrole/polystyrene sulfate films and subjected to an electrical stimulus showed a significant increase in neurite lengths compared with ones that were not subjected to electrical stimulation. In addition, the spreading morphous for PC-12 cells grown subjected to an electrical stimulus was greater than ones in control groups, but no cytotoxic reaction occurred. In vivo experiment proved no inflammatory response was induced by polypyrrole/polystyrene sulfate films. The polypyrrole/polystyrene sulfate film is a suitable material and shows good histocompatibility.