3D printed MXene (Ti₂AlN)/polycaprolactone composite scaffolds for in situ maxillofacial bone defect repair

Obtaining a safe and reliable scaffold that can be rapidly fabricated and used for clinical bone defect repair has always been a challenge. In this study, polycaprolactone (PCL) composite scaffolds with various MXene (Ti2AlN) contents were prepared using 3D printing technology. The effects of different contents of Ti2AlN on the mechanical properties, hydrophilicity, cytocompatibility, and osteogenic differentiation ability were systematically studied and analysed. In vitro experiments showed that scaffolds containing 5% Ti2AlN (PCL@5#Ti2AlN) obtained the best cell adhesion and proliferation ability and significantly upregu-lated the alkaline phosphatase (ALP) level. In vivo experiments of tibial defect repair in rats showed that the PCL scaffold containing 5% Ti2AlN (PCL@5#Ti2AlN) could significantly promote the formation of new bone, and the experimental results of rabbit maxillofacial bone defect repair further proved that the PCL@5#Ti2AlN scaffold could effectively promote the repair of bone defects. Transcriptome analysis indi-cated that Ti2AlN may promote osteogenic differentiation by the Wnt/B-catenin signaling pathway and calcium-binding proteins. These findings suggest that Ti2AlN/PCL composite scaffolds with improved in situ bone repair ability represent an intelligent strategy for bone defect repair.(c) 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.