Ketoprofen-loaded PLGA-based bioactive coating prepared by supercritical foaming on a TiAl6V4 substrate for local drug delivery in orthopedic applications

In this study, a novel biodegradable poly(lactic-co-glycolic) acid coating containing a model anti-inflammatory drug (ketoprofen) was prepared on TiAl6V4 substrate for use in orthopedic medicine by a two-step process combining drop casting and supercritical CO2-assisted foaming. The prepared coating was first investigated by surface analysis techniques using time-of-flight secondary ion mass spectrometry and X-ray photoelectron spectroscopy. The combined results confirmed the loading of ketoprofen and its homogeneous spatial distribution in the coating. 3D profilometry revealed increased surface roughness of the coating compared to the bare TiAl6V4 substrate, which is favorable for cell adhesion. Furthermore, the electrochemical measurements (i.e., electrochemical impedance spectroscopy and potentiodynamic curve measurements) demonstrated that the coating application significantly mitigated corrosion compared to the bare TiAl6V4 substrate. In vitro drug release tests revealed extended drug release in simulated body fluids with zero-order release kinetics. Finally, the promising cell testing results using adipose-derived mesenchymal stem cells and osteoblasts confirmed the applicability of the coating for implants. Overall, the results of this study highlight the significant potential of the developed bioactive coating for future orthopedic applications.