The study of mechanical and drug release properties of the mineralized collagen/polylactic acid scaffold by tuning the crystalline structure of polylactic acid

Abstract

Open bone fractures in clinical are not only difficult to heal but also at a high risk of infections. Annual cases of fractures which result from osteoporosis amount to approximately 9 million. The objective of this study is to load the antibiotic drug of vancomycin and tune its controlled delivery on a bone repair scaffold material of Mineralized Collagen/poly(lactic acid) (MCP) via changing the crystallinity of poly(lactic acid) to achieve inhibiting infection while repairing defects. We explored the crystallization process of the material during molding and prepared non-crystalline MCP1, MCP2, MCP3 and MCP4 by rapid freeze forming and crystalline MCP5 by tuning temperature decreasing rate. This method can control the micropore structure of the material; and the material changes from brittleness to toughness, which greatly enhances the control of mechanical properties. The drug release behavior of the material was studied for 28 days. Furthermore, the antibacterial property of the material was tested by the zone of inhibition, which shows the material good bacteriostasis. The controllable MCPs are expected to be substitutes for the treatment of infectious bone defects applying to clinical practical treatment.

Keywords:

• Rapid freezing
• polylactic acid
• controlled release of vancomycin
• crystalline
• mechanical properties

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Key Research and Development Program of Shanxi Province, China (International Cooperation) (no. 201803D421076 and 201803D421060), China Scholarship Council (no. 201906935015), National Natural Science Foundation of China (NSFC no. 51502192, 11872263, 31700689 and 11502157), Shanxi Province Science Foundation for Youths (no. 201801D221280).