Preparation and Properties of <scp>3D</scp>‐Printed Hydrogel‐Embedded <scp>PLA</scp> Composite Scaffolds

ABSTRACT This study presents the development of a biodegradable composite scaffold designed to address the limitations associated with conventional bone repair materials. 3D‐printing filaments were developed using fish scale powder (FSP) or fish scale‐derived hydroxyapatite (HAP), polylactic acid (PLA), and polycaprolactone (PCL), with a focus on the optimal effect of 5 wt% HAP on the mechanical properties of PLA. Composite scaffolds were further prepared by integrating 3D‐printed grid scaffolds with chitosan/gelatin composite hydrogels through vacuum freeze‐drying. The properties of the composite scaffolds were evaluated through mechanical property tests, thermal analysis (including DSC and TGA), absorption rate assessments (conducted via immersion experiments in various solutions), and surface morphology analyses (utilizing SEM and EDS). The results show that the addition of HAP significantly improves the mechanical properties of 3D‐printed filaments. The high absorption rate exhibited by the HAP/PLA composite scaffold suggests improved biocompatibility and its potential for in vivo tissue fluid absorption. The HAP/PLA composite scaffold showed visible surface mineralization and degradation after 10 days of immersion in simulated body fluid (SBF), highlighting its potential for bone repair and regeneration.