Biodegradable Zinc-Magnesium Alloy Scaffolds with Controlled Porosity for Bone Tissue Engineering

摘要

This work reports the design, fabrication, and in vitro evaluation of biodegradable Zn-3Mg alloy scaffolds with graded porosity produced by selective laser melting (SLM). Three scaffold architectures with porosities of 45%, 60%, and 75% were designed using triply periodic minimal surface (TPMS) gyroid topology. Mechanical testing revealed that the 60% porosity scaffold achieves a compressive strength of 48 MPa and elastic modulus of 3.2 GPa, closely matching the properties of cancellous bone. In vitro degradation studies in simulated body fluid (SBF) demonstrated a controlled corrosion rate of 0.18 mm/year, with the formation of biocompatible hydroxyapatite surface layers. Cell culture experiments with MC3T3-E1 osteoblasts confirmed excellent cytocompatibility with >92% cell viability after 7 days.