Characterization of the Influence of Bovine Serum Albumin (BSA) upon the Electronic Properties and Surface Topography of a Ti-3Cu Biomedical Alloy by Mott-Schottky Analysis (MSA) and Atomic Force Microscopy (AFM)

Abstract

The electronic characteristics, surface topography, and surface roughness of a Ti-3Cu alloy were investigated in phosphate buffered saline (PBS) containing bovine serum albumin (BSA) at 37 °C and pH 7.4 ± 0.2 by Mott-Schottky analysis (MSA) and atomic force microscopy (AFM). The n-type oxide layer was produced on the Ti-3Cu alloy surface due to the formation of oxygen-deficient TiO_2-x barrier layer with interstitial copper as ${ Cu}_i^{+}.$ As the serum-protein concentration increased from 1 g/L to 6 g/L in the phosphate buffered saline, the donor densities (N_D) of the semiconducting oxide layer decreased. The accumulation of serum protein observed by atomic force microscopy became the driving force in the restructuring of the oxide film via chemisorption and caused a reduction in the donor densities. The change in the magnitude of the nano-roughness suggested chemisorption which is beneficial for the osseointegration of Ti-3Cu implants.

Keywords:

• Aatomic force microscopy (AFM)
• bovine serum albumin (BSA)
• Mott-Schottky analysis (MSA)
• protein adsorption
• Ti-3Cu alloy

Additional information

Funding

This work was financially supported by the National Key Research and Development Program of China (2018YFC1106601) and the Liaoning Revitalization Talents Program (XLYC1807069). The authors would like to acknowledge the support of the Metallurgical Engineering Department, NED University of Engineering and Technology for the use of the atomic force microscope (AFM).