Investigation of composition effect on PLGA/hydroxyapatite hybrid materials

Miki Hayashi, Yuko Takeoka, Mamoru Aizawa, Masahiro Rikukawa, Kohei Sanui

Research output: Contribution to conferencePaper


Hydroxyapatite (Ca10(PO4)6(OH) 2; HAp) has been used as a biomaterial due to its similarity to bone mineral in structure and composition, and its good biocompatibility to human tissue. Recently, much attention has been focused on the combination of HAp composites with biodegradable polymers to overcome the problem of poor mechanical properties of HAp. In this study, poly(lactic-co-glycolic acid) (PLGA) were synthesized by enzymatic polymerization using lipase in order to control the crystallinity and biodegradability, and PLGA/HAp hybrid materials were fabricated to control their mechanical properties. The molar fraction of L-lactide (FL) in PLGA was calculated from the 1H NMR spectra. The 1H NMR results indicated that the reactivity of glycolide was higher than that of L-lactide. The FL of PLGA polymerized in and outside HAp for 9 days was equal to the feed ratio of L-lactide. The DSC results showed that the Tm of PLGA decreased with increasing FL, indicating that the degree of crystallinity of PLGA decreased upon copolymerization with PLLA. The X-ray diffraction peaks of PLGA (F L = 50 %) was consistent with that of PGA. The ATR spectra, 1H NMR spectra, and SEM images showed that the PLGA was introduced into the HAp pores by the in-situ method.

Original languageEnglish
Number of pages2
Publication statusPublished - 1 Dec 2005
Event54th SPSJ Symposium on Macromolecules - Yamagata, Japan
Duration: 20 Sep 200522 Sep 2005


Conference54th SPSJ Symposium on Macromolecules



  • Artificial bone
  • Enzymatic polymerization
  • Hydroxy apatite
  • PLGA

Cite this

Hayashi, M., Takeoka, Y., Aizawa, M., Rikukawa, M., & Sanui, K. (2005). Investigation of composition effect on PLGA/hydroxyapatite hybrid materials. 4923-4924. Paper presented at 54th SPSJ Symposium on Macromolecules, Yamagata, Japan.