Temperature Influence on the Aging of Titanium Surfaces Treated With Cold Atmospheric Plasma: Impact on Physicochemical Properties and Biological Responses

Titanium surfaces treated with cold atmospheric plasma exhibit enhanced wettability, cell adhesion, and surface energy; however, these beneficial effects tend to diminish over time due to aging-related changes caused by surface recontamination and the gradual loss of reactive species. This study investigates the influence of surface temperature during cold atmospheric plasma (CAP) treatment on the aging behavior of titanium, with a focus on time-dependent changes in physicochemical properties and biological responses. Titanium samples were treated with CAP at controlled surface temperatures of 40°C, 100°C, and 200°C. Treatment at 100°C and 200°C increased surface roughness, with more rounded peaks observed at 200°C. While wettability initially improved after treatment, it gradually declined over time, with the 200°C-treated samples exhibiting the smallest reduction. Biological assays revealed enhanced cell adhesion on surfaces treated at 100°C and 200°C, with scanning electron microscopy (SEM) showing filopodia formation and cell spreading. The Live/Dead assay confirmed improved cell viability on these surfaces. The AlamarBlue assay indicated that surfaces treated at 40°C and 100°C initially supported the highest cell proliferation, while the 200°C-treated samples maintained the most stable proliferation levels over a 15-day aging period. These findings underscore the impact of surface aging on biomedical device performance, highlighting its influence on the biological response. CAP treatment at 200°C provides durable surface modifications that preserve Ti biocompatibility over time, emphasizing the potential of advanced surface treatments to enhance the longevity and functionality of Ti-based biomedical implants.