Enhancing PLA Filament Biocompatibility by introducing ZnO and Ketoprofen

Abstract

This study investigates the incorporation of zinc oxide (ZnO) and ketoprofen (keto) into poly(lactic acid) (PLA) filaments to enhance their biocompatible. PLA is widely used in additive manufacturing, especially in biomedical applications, due to its biodegradability and biocompatibility. However, its interaction with biological tissues can be improved. ZnO was chosen for its wound-healing properties, while keto, a nonsteroidal anti-inflammatory drug, was selected to provide local anti-inflammatory effects. PLA filaments were prepared by incorporating ZnO and keto, followed by analyses of their mechanical, thermal, and biological properties. The results showed that the incorporation of ZnO and keto did not compromise the mechanical and thermal properties of the PLA filaments. Compared to pristine PLA, the composites presented a slight improvement in strength. The incorporation of ketoprofen in the composite increased its thermal stability compared to PLA-ZnO filament. Concerning the morphology, when ZnO and Keto were inserted, the scaffold acquired a more robust structure, with well-defined porosity. In vitro biocompatibility tests indicated that the modified filaments exhibited lower cellular toxicity and improved cell adhesion and proliferation compared to pure PLA. Antimicrobial tests demonstrated that the filaments containing ZnO, at the evaluated concentration, did not exhibit activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, gram-positive and gram-negative bacteria. The combination of ZnO and ketoprofen in PLA filaments can enhance their biomedical applications, providing better biocompatibility without compromising the intrinsic characteristics of PLA. This work paves the way for the development of safer and more effective medical implants and devices.