聚苯胺/聚乳酸复合纳米纤维表面形貌对生物相容性的影响

外加电场作用下聚苯胺能够调节细胞附着、增殖、迁移和分化，在体液环境下发生脱掺杂会使聚苯胺基导电可降解纳米纤维电活性减弱，但在一定程度上仍能促进细胞的黏附、生长和增殖。本文选择酒石酸作为聚苯胺在等离子体处理后的聚乳酸纳米纤维表面原位聚合过程中的酸掺杂剂，考察酒石酸与苯胺摩尔比分别在1∶1， 1∶2和1∶4下不同形貌的聚苯胺/聚乳酸复合纳米纤维对生物相容性的影响。采用SEM、TEM和FTIR表征聚苯胺形貌及化学成分，接触角评价其润湿性，MTT、ALP和免疫荧光染色评价聚苯胺/聚乳酸复合纳米纤维生物相容性。结果表明，酒石酸与苯胺摩尔比在1∶1、1∶2和1∶4下的聚苯胺形貌分别为纳米颗粒状、纳米纤维状和纳米空心管状，聚苯胺附着在聚乳酸纳米纤维表面，不会对静电纺丝的多孔结构基体产生影响；聚苯胺/聚乳酸复合纳米纤维表面润湿性良好，有助于细胞的黏附和生长；纳米纤维状的聚苯胺对生物相容性的增强效果明显优于纳米颗粒状聚苯胺，而纳米空心管状结构的聚苯胺对生物相容性增强作用更佳。

Effect of biocompatibility on surface morphology of polyaniline/polylactic acid composite nanofibers

Polyaniline (PANI) can regulate cell adhesion, proliferatio, and differentiation under the external electric field. However, the electrical activity of polyaniline based degradable nanofibers will be weakened because of PANI dedoped in the body physiological environment. Yet it could promote the cell adhesion, growth and proliferation. In this paper, tartaric acid was selected as the acid dopant in the in-situ polymerization of polyaniline on the surface of polylactic acid (PLA) nanofibers after plasma treatment. The effects of different morphologies of polyaniline/polylactic acid (PANI/PLA) composite nanofibers with the different molar ratio of tartaric acid to aniline at 1∶1, 1∶2 and 1∶4 were investigated. The morphology and chemical composition of polyaniline were characterized by SEM, TEM and FTIR. The wettability was evaluated by contact angle. The biocompatibility of PANI/PLA composite nanofibers was evaluated by MTT, ALP and immunofluorescence staining. The results showed that the morphology of polyaniline with the molar ratio of tartaric acid to aniline at 1∶1, 1∶2, and 1∶4 was nanoparticles, nanofiber and nano-hollow tubes, respectively. PANI attached to the surface of PLA nanofibers did not affect the porous structure of electrospinning. The surface wettability of PANI/PLA composite nanofibers was excellent, which was helpful for cell adhesion and growth. The biocompatibility of nanofiber polyaniline was better than that of nanoparticle polyaniline, and the effect of nano-hollow tubular polyaniline on biocompatibility was much better.