High-precision,gelatin-based,hybrid,bilayer scaffolds using melt electro-writing to repair cartilage injury

Articular cartilage injury is a common disease in the field of orthopedics.Because cartilage has poor self-repairing ability,medical intervention is needed.Using melt electro-writing(MEW)technology,tissue engineering scaffolds with high porosity and high precision can be prepared.However,ordinary materials,especially natural polymer materials,are difficult to print.In this study,gelatin was mixed with poly(lactic-co-glycolic acid)to prepare high-concentration and high-viscosity printer ink,which had good printability and formability.A composite scaffold with full-layer TGF-β1 loading mixed with hydroxyapatite was prepared,and the scaffold was implanted at the cartilage injury site;microfracture surgery was conducted to induce the mesenchyme in the bone marrow.Quality stem cells thereby promoted the repair of damaged cartilage.In summary,this study developed a novel printing method,explored the molding conditions based on MEW printing ink,and constructed a bioactive cartilage repair scaffold.The scaffold can use autologous bone marrow mesenchymal stem cells and induce their differentiation to promote cartilage repair.