A Nanoindentation Approach for Time-Dependent Evaluation of Surface Free Energy in Micro- and Nano-Structured Titanium

• Published in: Materials Vol. 15; no. 1; p. 287
• Main Authors: De Santis, Serena, Rossi, Edoardo, Sebastiani, Marco, Sennato, Simona, Bemporad, Edoardo, Orsini, Monica
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 31.12.2021; MDPI
• Subjects: aging; Biocompatibility; Bonding strength; Bones; chemical treatment; Contact angle; Etching; Experiments; Free energy; Morphology; Nanoindentation; Nitrogen; Nondestructive testing; Scanning electron microscopy; Software; surface free energy; Surface treatment; Time dependence; Tissue engineering; Titanium; Italy; chemical treatment; surface free energy; nanoindentation; aging; titanium
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma15010287

Surface free energy (SFE) of titanium surfaces plays a significant role in tissue engineering, as it affects the effectiveness and long-term stability of both active coatings and functionalization and the establishment of strong bonds to the newly growing bone. A new contact-mechanics methodology based on high-resolution non-destructive elastic contacting nanoindentation is applied here to study SFE of micro- and nano-structured titanium surfaces, right after their preparation and as a function of exposure to air. The effectiveness of different surface treatments in enhancing SFE is assessed. A time-dependent decay of SFE within a few hours is observed, with kinetics related to the sample preparation. The fast, non-destructive method adopted allowed for SFE measurements in very hydrophilic conditions, establishing a reliable comparison between surfaces with different properties.