Dr. Yonggang Zhang


Project description


In the past decades, extensive research efforts have been expended in the fields of materials science and scaffolding technologies, however, developing synthetic bone graft substitutes that are both load-bearing and highly bioactive remains a challenge. Polylactide (PLA) and polycaprolactone (PCL) have received increasing attention due to their biodegradability and biocompatibility and both polymers have been approved by the Food and Drug Administration (FDA) for medical applications. Compared with many natural biopolymers, PLA and PCL exhibit better mechanical properties [1]. Therefore, they have been extensively studied for the fabrication of synthetic bone graft substitutes. However, slow degradation rate, poor wettability, poor mechanical properties, and lack of cell adhesion and integration into the surrounding tissue constrain their clinical application. With the aim of improving bioactivity, while retaining the superior mechanical proprieties, polymers such as PCL and PLA have been combined with inorganic bioactive materials, offering the possibility to obtain implants with tailored physical, mechanical, and biological properties. Bioactive phases in polymer composite can enhance osteoconductivity, improve wettability, and, depending on the method of blending, increase mechanical properties that are essential for load bearing applications. Conventional methods of physical blending of polymers with bioactive ceramic micro- or nanosized have a limited effect on the mechanical properties of polymers [2]. In this project, we aim to synthesize biodegradable, osteoconductive and osteoinductive ceramic/PCL(PLA) composites with anisotropic structure at micro and macroscale. One-dimensional (1D) hydroxyapatite ceramic particles act as the mechanical reinforcement material, as well as to improve the wettability and bioactivity (osteoconductivity and osteoinductivity) of the polymers.


Techniques: 3D printing


Keywords: one-dimensional, hydroxyapatite, PCL, PLA, load-bearing