In Vivo Tissue Response and Degradation Behavior of PLLA and Stereocomplexed PLA Nanofibers

Abstract

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.

Electrospun poly lactic acid (PLA) fibres: Effect of different solvent systems on fibre morphology and diameter

“…In another study Prabhakaran et al [20] produced PLLA nanofibres with a diameter of 860±110 nm (M w PLA =100 kDa) from a hexafluoroisopropanol (HFIP) solution 16% (w/v), On the other hand, Ishii et al [21] dissolved PLLA (M w =850 kDa) in HFIP at a concentration of 1 wt.% and produced nanofibre with a mean diameter of 300 nm. This shows that molecular weight is another important variable.…”

Biomaterials Applicable for Alveolar Sockets Preservation: In Vivo and In Vitro Studies

“…inflammatory response by infiltrating mononuclear and polynuclear inflammatory cells in animals (de Tayrac et al 2008). Furthermore, stereocomplexed PLA nanofibers induced milder inflammatory reaction than poly(L-lactide) nanofibers after subcutaneous implantation in rats (Ishii et al 2009). …”

Micro- and nanostructures of polylactide stereocomplexes and their biomedical applications

“…These features make them perfect candidates for wound healing materials. 64 An intriguing example of another approach to stereocomplex application is use as a dielectric layer in organic field-effect transistors (OFETs). Low melting temperature and thermal instability of PLAs during device fabrication and operation are the main drawbacks for their use in biomaterial-based electronics.…”