In Vitro Degradation and Cytocompatibility Study of Biodegradable Porous Zinc Scaffolds Fabricated by Fused Deposition Modeling Based Rapid Tooling Method.

An integrative study is conducted on the static biodegradation behavior and cytocompatibility of organized porous network structured (OPNS) zinc scaffolds fabricated via the Fused Deposition Modeling based Rapid Tooling (FDM-RT) method. The degradation study investigates the corrosion mechanism over immersion time in simulated body fluid (SBF), whereas the cytocompatibility study incorporates MTT assay and direct cell counting tests. The results indicate that the scaffold morphology, including scaffold struts, interconnectivity, or porosity, along with the immersion period, significantly influence the degradation behavior. The static corrosion rates are determined to be 0.27 ± 0.006, 0.79 ± 0.01, and 1.35 ± 0.05 mm y-1 for bulk and porous zinc samples after 28 days. The higher corrosion rate of porous zinc alloys is mainly due to their higher surface area, which enhances exposure to the solution. Over time, protective layers form on both porous and bulk samples, leading to a gradual decrease in corrosion rate. The XRD results reveal that the corrosion protective layer is primarily composed of ZnO, Ca3(PO4)2, Zn (OH)2, and Zn3(PO4)2·4H2O. Moreover, MTT assay and direct cell counting of mouse fibroblast 3T3 cells on bulk and porous zinc samples suggest that the prepared zinc samples have potential for tissue engineering applications.