Protein adhesion to Chromium Nitride coatings

The current artificial joint materials need to be further improved for adhesion and service life. In the present research, the adhesion of albumen protein to CrN and CrAlN coatings on Ti alloy and Si wafer is studied via rotational shear flow. CrN and CrAlN coatings provide improved wear resistance over pure Cr. These coatings offer a potential alternative to reduce wear in artificial joints. Previous research has demonstrated that there are two factors that affect protein adhesion: surface roughness and surface chemistry. Here we study effects of material and surface properties of those coatings on protein adhesion. Experimentally, we developed a method to quantitatively evaluate the adhesive strength of proteins to the surface. Subsequently we study the interfacial mechanisms between coating surfaces and protein molecules. Results indicate that the protein adhesion depends on the substrate chemistry. The CrN and CrAlN coatings improve wear resistance with minimum to no influence with the substrate's interaction with the proteins.