Ishii Daisuke, Ying Tang Hui, Mahara Atsushi, Murakami Sunao, Yamaoka Tetsuji, Lee Won-ki, Iwata Tadahisa
Polymer Chemistry Laboratory, RIKEN Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
Biomacromolecules. 2009 Feb 9;10(2):237-42. doi: 10.1021/bm8009363.
Biocompatibility of PLLA and stereocomplexed PLA nanofibers was evaluated by subcutaneous implantation in rats for 4-12 weeks. Characterization of the nanofibers was performed by GPC, SEM, wide-angle X-ray diffraction, and optical microscopy of hematoxylin-eosin stained ultrathin sections of explanted nanofibers. Stereocomplexed PLA nanofiber showed slower degradation than PLLA nanofiber and thus retained their shape after prolonged implantation. Furthermore, stereocomplexed PLA nanofiber caused milder inflammatory reaction than PLLA nanofiber. These results offer the potential use of PLLA and stereocomplexed PLA nanofibers as a biomaterial for short-term and long-term tissue regeneration, respectively. Stereocomplexed PLA nanofiber after in vitro degradation showed smaller degree of swelling than PLLA nanofiber. Taking the results of in vivo degradation together with in vitro degradation into consideration, bioabsorption mechanism of the in vivo degradation of the nanofibers is proposed.
通过在大鼠皮下植入4至12周来评估聚乳酸（PLLA）和立体复合聚乳酸（PLA）纳米纤维的生物相容性。通过凝胶渗透色谱法（GPC）、扫描电子显微镜（SEM）、广角X射线衍射以及对取出的纳米纤维苏木精-伊红染色超薄切片进行光学显微镜观察来对纳米纤维进行表征。立体复合PLA纳米纤维的降解速度比PLLA纳米纤维慢，因此在长时间植入后仍能保持其形状。此外，立体复合PLA纳米纤维引起的炎症反应比PLLA纳米纤维更轻微。这些结果表明，PLLA和立体复合PLA纳米纤维分别具有作为短期和长期组织再生生物材料的潜在用途。体外降解后的立体复合PLA纳米纤维的肿胀程度比PLLA纳米纤维小。综合体内降解和体外降解的结果，提出了纳米纤维体内降解的生物吸收机制。
