Plasma‐Modified PTFE for Biological Applications: Correlation between Protein‐Resistant Properties and Surface Characteristics

Abstract

PTFE samples were treated by low-pressure, O₂ RF plasmas. The adsorption of BSA was used as a probe for the protein resistant properties. The exposure of PTFE to an O₂ plasma leads to an increase in the chamber pressure. OES reveals the presence of CO, CO₂ and F in the gas phase, indicating a strong etching of the PTFE surface by the O₂ plasma. Furthermore, the high resolution C1s spectrum shows the appearance of CF₃, CF and C-CF components in addition to the CF₂ component, which is consistent with etching of the PTFE surface. WCA as high as 160° were observed, indicating a superhydrophobic behaviour. AFM Images of surfaces treated at high plasma power showed a increase in roughness. Lower amounts of BSA adsorption were detected on high power, O₂ plasma-modified PTFE samples compared to low power, oxygen plasma-modified ones.