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

Abstract

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.

Effect of the Composition of Copolymers Based on Glycidyl Methacrylate and Fluoroalkyl Methacrylates on the Free Energy and Lyophilic Properties of the Modified Surface

“…The calculation of the SFE of superhydrophobic coatings yields extremely low values ( Table 2 ) [ 58 , 59 ]. This is due to an increase in the wetting angles used for the calculation owing to the multilevel roughness of the near-surface layer of the material.…”

Quantitative surface free energy with micro-colloid probe pairs

“…Acceptance of SFE characterisation on a global scale requires standardization and agreement between the several techniques probing adhesion across the different length scales, such as CA measurements, nano-indentation and AFM. 11,20,[33][34][35][36][37] These techniques are all well-developed and provide reproducible measurements of adhesion in controlled environment and with controlled probes. The generation of a quantitative, holistic perspective between these techniques should be addressed with innovative protocols to correlate the data collected by these techniques, that is by increasing the reliance on data-based models.…”

Cerium Coatings on Pristine and Nanostructured Ti and Ti6Al4V Surfaces: Bioactivity, Resistance in Simulated Inflammatory Conditions, and Antibacterial Performance

“…In fact, despite its historical reputation as an inert material, Ti implants consist in nonbiological components and, especially when it comes to the long-term performance of its alloys, there are some concerns due to the release of possibly harmful ions into the body . As a result, the choice of the biomaterial with appropriate surface characteristics is critical for controlling the human body response and to ensure rapid osseointegration in order to form a robust bone–implant relationship. , …”

“…3 As a result, the choice of the biomaterial with appropriate surface characteristics is critical for controlling the human body response and to ensure rapid osseointegration in order to form a robust bone−implant relationship. 4,5 Nowadays antibiotic resistance has become an ever-growing problem affecting various fields including that of biomedical implants and devices. 6,7 Therefore, to deal with the existing drug-resistant bacterial issues, the use of alternative antibacterial agents has been receiving increasing interest compared with conventional antibiotic agents.…”