“…The key features of optimal biomaterials are as follows: surface protection, biocompatibility, antimicrobial and anti-tumor properties, as well as directed differentiation of stem/progenitor cells (Yoshida et al, 2013;Zhang et al, 2019). Utilizing air-plasma treatment for coatings has been shown to enhance the wear resistance and corrosion resistance of substrate surfaces (Fenker et al, 2002;Khorasanian et al, 2011;Tsunekawa et al, 2011;Wang et al, 2011;Hussein et al, 2017). Recently, various reports have demonstrated the enhanced biocompatibility of surfaces modified with air-plasma treatment (Liu et al, 2005;Lu et al, 2012).…”