Biodegradation profiles of chitin, chitosan and titanium reinforced polylactide biocomposites as scaffolds in bone tissue engineering

Abstract

In this study, chitin (Ct), chitosan (Ch) and titanium powder (Ti) were melt-blended with polylactide (PLA) to produce three composites of PLA. The samples were subjected to multiple characterisations, which includes immersion in a phosphate buffer solution (PBS) for ten weeks. The results showed that the three fillers reduced the hydrophobicity of PLA, making the reinforced samples to be more hydrophilic. In addition, the organic reinforced PLA composites became more amorphous while the PLA/Ti samples became more crystalline when compared with unreinforced PLA. The results of the samples’ immersion in PBS showed that the organic reinforced PLA presented a biodegradation profile that would allow for the required gradual transfer of load to the partially healed fractured bone. Except for the chitin reinforced PLA (PLA/Ct) with 16.67 wt. %, all other composites produced using the organic fillers gave a swelling percentage which was less than 17%. However, titanium-reinforced PLA (PLA/Ti) composites were found to continue to swell after ten weeks of the immersion of the samples. Although all the samples formed apatite on their surfaces (except the unreinforced PLA), the biodegradation profile of PLA/Ti was deemed unsuitable as an implant because of the possibility of postoperative palpability.

Keywords

• bio-composites scaffold
• hydrolytic degradation
• bone internal fixation
• hydrophobicity effect
• formation of apatite