Bioabsorption of polylactides with different molecular properties

✍ Scribed by Nakamura, T. ;Hitomi, S. ;Watanabe, S. ;Shimizu, Y. ;Jamshidi, K. ;Hyon, S.-H. ;Ikada, Y.

• Book ID: 102875300
• Publisher: John Wiley and Sons
• Year: 1989
• Tongue: English
• Weight: 1021 KB
• Volume: 23
• Category: Article
• ISSN: 0021-9304
• DOI: 10.1002/jbm.820231003

✦ Synopsis

In order to study the effects of factors governing the bioabsorption rate of polylactides, implantation tests were camed out in rabbits using various samples (20 x 10 x 2 mm3) differing in their chemical composition, residual monomer content, and molecular orientation. Copolymer samples with a higher lactic acid content showed a lower rate of absorption, whereas those with a higher unreacted monomer content were absorbed faster and showed a more drastic decrease in molecular weight. In contrast, degradation of the purified polymers was slow; the purified poly-L-lactide showed no weight change and a 50% reduction in molecular weight after 6 months of implantation. Scanning electron microscopy of the samples containing monomers showed a microporous structure extending from the surface to the inner region a few days after implantation, whereas the purified poly-L-lactide did not exhibit a microporous structural change even after 10 months of implantation.