Investigating the Influence of Additive Manufacturing and Ultrasonic Coating Parameters on Biopolymeric Scaffold...

Triply periodic minimal surface (TPMS) scaffolds have gained attention in additive manufacturing due to their unique porous structures, which are useful in biomedical applications. Unlike metallic implants that can cause stress shielding, polymeric scaffolds offer a safer alternative. This study is focused on enhancing the compressive strength of additive-manufactured polylactic acid (PLA) scaffolds with a diamond structure. The response surface methodology (RSM)-based experimental design was developed to study the influence of printing parameters. The fused deposition modeling (FDM) process parameters were optimized, achieving a compressive strength of 56.2 MPa. Subsequently, the scaffolds were fabricated at optimized parameters and underwent ultrasonic-assisted polydopamine coating. With the utilization of the RSM approach, the study examined the effects of ultrasonic vibration power, coating solution concentration, and submersion time on compressive strength. The optimal coating conditions led to a maximum compressive strength of 92.77 MPa-a 65.1% improvement over the uncoated scaffold. This enhancement is attributed to the scaffold's porous structure, which enables uniform coating deposition. Energy-dispersive x-ray spectroscopy confirmed the successful polydopamine coating, with 10.64 wt% nitrogen content. These findings demonstrate the potential of ultrasonic-assisted coating in improving the mechanical properties of PLA scaffolds, making them suitable for biomedical applications.