3D Printing of Bone Scaffolds Based on Alginate/Gelatin Hydrogel Ink Containing Bioactive Glass 45S5 and ZIF‐8 Nanoparticles with Sustained Drug‐Release Capability

Herein, 3D printing coupled with drug‐release systems introduces many advantages to bone‐regenerative medicine. In this research, hydrogel‐based nanocomposite inks comprising alginate/gelatin (Alg/Gel) matrix supplemented with mesoporous bioactive glass (MBG) and zeolite‐imidazole framework‐8 (ZIF‐8) nanoparticles are presented. A fixed wt% of mixed nanoparticles at MBG/ZIF weight ratios of 85:15 and 70:30 is added to Alg/Gel to prepare nanocomposite inks. All inks have shear‐thinning behavior, facilitating scaffolds’ 3D printing via extrusion. Scaffolds’ 3D spatial and nanocomposite microstructures are confirmed using field‐emission scanning electron microscope and energy‐dispersive X‐ray (FESEM/EDX) and Fourier transform infrared (FT‐IR). Shear punch testing indicates an enhanced shear strength of 85:15 samples in both dry (9.49 ± 0.23 MPa) and wet conditions (1.19 ± 0.16 MPa). After 1 month, nanocomposite scaffolds have a higher degradation rate (65%) than Alg/Gel (50%) in phosphate‐buffered saline. In vitro drug‐release study using UV–visible spectrophotometry exhibits a similar prolonged release profile for 85:15 and 70:30 nanocomposites compared to Alg/Gel. Due to its better mechanical performance, 85:15 is used for bioactivity and cellular tests. MBG provides bioactivity in simulated body fluid by the rapid development of hydroxyapatite validated by FESEM/EDX, XRD, and FT‐IR. Nanocomposite scaffolds exhibit significantly higher MG‐63 cell viability (>90%) than Alg/Gel. Finally, these scaffolds provide a potential additive‐manufacturing solution to bone tissue regeneration.