Physicochemical and Biological Expressions of Biodegradable 3D-printed Apatite/Calcium Sulfate Scaffolds

Objectives: Tissue engineering strategies have been tackled in leveraging 3D printing technology for engineered bone over past few years. There were several studies indicated that bioscaffolds composed of polymers and inorganic materials through 3D printing process provided substantially osteogenic activity and cellular benefits. Among the variety of biocompatible polymers, polycaprolactone (PCL) have been approved for clinical use without toxicity when fed to metabolic pathways and the low melting point makes it a high performance printable biomaterial in a lab environment. However, the flaws of PCL still lack in its suitable biodegradability and hydrophilicity behavior. Bioceramics based on apatite and calcium sulfate materials were drawn much attention owing to their high biological activity, which has excellent osteogenic differentiation both in vitro and in vivo. To check its effectiveness, a series of calcium sulfate/apatite with different ratios were prepared to make new bioactive and biodegradable bioscaffold for bone repair.
Methods: This study proposed a facile route for fabricating the ideal porous 3D scaffolds with tailored degradability and osteogenic activity by introducing apatite-calcium sulfate into PCL. The diametral tensile strength and weight loss of composites were considered before and after immersion in simulated body fluid. We also considered the behavior of human mesenchymal stem cells (hMSCs) cultured on apatite-calcium sulfate/PCL bioscaffolds.
Results: As the results, the in vitro degradation experiments shown that the weight of apatite-calcium sulfate/PCL scaffolds lost 52% after three months. In addition, the data indicated that the addition of apatite-calcium sulfate significantly improved the wettability on the surface of PCL. This also directly further promotes cell behaviors. Moreover, the apatite-calcium sulfate/PCL scaffolds offered higher levels of osteogenic-related gene expression of Wharton’s Jelly mesenchymal stem cells.
Conclusions: These results suggest that the apatite-calcium sulfate/PCL composites may have a potential application for bone regeneration.