Fabrication and Biological Activity of 3D-Printed Polycaprolactone/Magnesium Porous Scaffolds for Critical Size Bone Defect Repair

Abstract

Polycaprolactone (PCL) is widely used in bone tissue engineering due to its biocompatibility and mechanical strength. However, PCL is not biologically active and shows poor hydrophilicity, making it difficult for new bones to bind tightly to its surface. Magnesium (Mg), an important component of natural bone, exhibits good osteo-inductivity and biological activity. Therefore, porous PCL/Mg scaffolds, including pure PCL, PCL/5%Mg, PCL/10%Mg, and PCL/15%Mg, were prepared to elucidate whether the porous structure of scaffolds and the bioactivity of PCL may be enhanced via 3D printing and incorporation of Mg powder. Compared with the control group (pure PCL only), the hydrophilicity of composite PCL/Mg scaffolds was greatly increased, resulting in the scaffolds having decreased water contact angles. Tests for adhesion and proliferation of rat bone marrow mesenchymal stem cells (rBMSCs) indicated that the PCL/10%Mg scaffold showed superior compatibility. Furthermore, as indicated by alkaline phosphatase (ALP) activity and semiquantitative analysis of alizarin red staining, PCL/10%Mg scaffolds exhibited significantly stronger osteogenic activity than the other scaffolds. Animal experiments demonstrated that PCL/10%Mg scaffolds displayed pro-osteogenic effects at an early stage (4 weeks) and produced more new bone mass 8–12 weeks following implantation, compared with the control group. Visceral and blood parameter analyses indicated that PCL/10%Mg scaffolds did not exert any noticeable toxic effects. PCL/10%Mg composite scaffolds were found to promote bone defect repair at an early stage with good cytocompatibility. This finding revealed a new concept in designing bone tissue materials, which showed potential as a clinical treatment for bone defects.

3D-printing magnesium–polycaprolactone loaded with melatonin inhibits the development of osteosarcoma by regulating cell-in-cell structures

“…Results demonstrated that Mg–PCL scaffold could promote bone growth and might be an ideal candidate for bone tissue engineering; however, it can’t inhibit tumor metastasis. This result is partly consistent with the study of Zhao et al, which demonstrated PCL/10% Mg composite scaffolds could promote bone defect repair at an early stage with good cytocompatibility [ 43 ].…”

Mediation of mechanically adapted TiCu/TiCuN/CFR-PEEK implants in vascular regeneration to promote bone repair in vitro and in vivo

“…Additionally, the rods prepared by extrusion were cut to obtain the wafers used in the experiment, which consequently caused uneven structures of the disc surface, as observed from the SEM images. Many studies have demonstrated that a rough structure is advantageous for cell adhesion and proliferation [ [24] , [25] , [26] ]. The SEM scanning results demonstrated that the TiCu/TiCuN coating was distributed in a granular form on the surface of the CFR-PEEK substrate, uniformly covering the PEEK matrix and the carbon fibre part.…”

Effects of Zinc, Magnesium, and Iron Ions on Bone Tissue Engineering

“…77,5 Zhao et al fabricated the PCL/magnesium porous scaffold and demonstrated that when the weight masses of magnesium particles were 5 and 10 wt %, the attachment of BMSCs' increased through enhanced surface hydrophilicity. 85 Yin et al found that the fraction of initial cell adhesion in hydrogels containing 100 mM Mg ions was 15.69%, which was much higher as compared to the control group (3.50 ± 1.40%). 86 It is proposed that magnesium adjusts the direction of fibronectin and enhances its receptors' affinity, resulting in increased integrin binding that promotes cellular adhesion.…”