Abstract The aim of this study was to fabricate an‎d characterize a bioactive an‎d biodegradable composite scaffold based on poly(lactic acid)/zinc-doped akermanite (PLA–AKZn). Nano-bioceramic akermanite an‎d zinc-doped akermanite were synthesized via the sol–gel method. The scaffolds containing 0, 10, 20, an‎d 30 wt% of akermanite an‎d Zn-doped akermanite were fabricated using fused deposition modeling (FDM) 3D printing. X-ray diffraction (XRD) was employed to confirm the presence of the desired crystalline phases in the powders an‎d scaffolds. The morphology an‎d pore distribution of the scaffolds were examined by scanning electron microscopy (SEM). The compressive test was used to eva‎luate the mechanical properties of the fabricated scaffolds. The hydro‎philicity of the scaffolds was assessed using water contact angle measurements. To investigate the bioactivity, the scaffolds were immersed in simulated body fluid (SBF) for 1 an‎d 4 weeks, an‎d the nucleation an‎d growth of hydroxyapatite on the scaffold surfaces were studied using SEM. The biodegradability of the scaffolds was eva‎luated by immersing them in phosphate-buffered saline (PBS) for 1, 2, 3, an‎d 4 weeks, followed by measurement of weight loss. Cytotoxicity was assessed through the MTT assay, an‎d cell viability was further examined using DAPI staining an‎d SEM imaging. XRD results confirmed the successful synthesis of Zn-doped akermanite, showing strong characteristic peaks of the akermanite phase, while the raw precursor phases were eliminated. In PLA-based nanocomposites containing akermanite an‎d Zn-akermanite, the ceramic particles increased the crystallinity of PLA an‎d stabilized the crystalline structure. SEM images revealed interconnected an‎d open pores suitable for cell infiltration, with fiber diameter an‎d pore size varying with particle content. FTIR spectra confirmed the preservation of Si–O, Mg–O, an‎d surface hydroxyl groups, an‎d the addition of Zn-akermanite enhanced surface interactions while slightly disturbing the polymer chain order. The incorporation of reinforcing particles improved the mechanical strength, with the 20 wt% Zn-akermanite scaffold exhibiting the highest strength an‎d flexibility. EDS analysis verified the uniform distribution of Ca, Mg, Si, an‎d Zn elements, an‎d hydroxyapatite deposition confirmed the bioactivity of the scaffolds. Overall, the 20 wt% Zn-akermanite composition provided an optimal balance between mechanical properties, crystallinity, an‎d bioactivity. MTT assay results demonstrated low cytotoxicity of PLA/akermanite an‎d PLA/Zn-akermanite nanocomposites, with good cell proliferation over time. Increasing the Zn-akermanite content up to 20% enhanced scaffold biocompatibility an‎d resulted in the highest cell proliferation rate, indicating a favorable environment for cell growth an‎d biological activity. These findings were consistent with microscopic observations, as the open an‎d interconnected pores facilitated cell penetration an‎d nutrient exchange. In summary, the MTT assay confirmed that Zn-akermanite addition not only improved the mechanical an‎d crystalline properties of the scaffold but also enhanced its biocompatibility, with the 20 wt% Zn-akermanite sample exhibiting the best cellular performance.

محمد خدائي

مهدي رفيعائي , عرفان عقيلي