Sol-Gel SiO₂ Coatings with Curcumin and Thymol on 3D Printouts Manufactured from Ti6Al4V ELI

Bacterial biofilm on implants may cause inflammation, which disturbs the process of the implant’s integration with the surrounding tissues. Such problems are becoming critical for patients’ health, especially in connection with the presence of antibiotic-resistant bacterial strains. Among the existing alternatives for drug treatments are natural-based substances. This study focused on the examination of silica coatings with curcumin and thymol, which were deposited using the sol-gel method on 3D printouts made of Ti6Al4V ELI. This substrate material is commonly used in medicine. The selective laser melting technique used for the manufacturing of samples was in line with the existing procedures applied for individual orthopedic implants. The examination involved the assessment of the coatings’ morphology, chemical composition, and biological effect. The antibacterial properties were tested using a flow cytometer using Escherichia coli, and the cytotoxicity on Saos-2 cells was assessed using the LIVE/DEAD test. The obtained results showed that it is possible to produce silica sol-gel coatings with the addition of specific natural substances in concentrations assuring a bacteriostatic effect. The produced coatings did not show any cytotoxic effect, which confirms the possibility of using both curcumin and thymol as additives to coatings used in medicine, e.g., for orthopedic implants.