Limiting platelet adhesion in stainless steel bio-implants through microstructural modification

Abstract

Thrombosis, resulting from platelet adhesion and attachment is one of the major issues with blood contacting implants. Limiting platelet adhesion is highly desirable to ensure the usefulness of implants in blood contacting applications. In this work, we report on simplistic low-temperature high strain-rate processing to minimize the platelet adhesion on biomedical grade stainless steel. In addition, processing was also done at low rotational speed to study the effect of strain rate during processing. At high rotational speed, the processed steel resulted in single-phase ultra-fine grain structure along with significantly lower metal ion-release and better hemocompatibility. In addition, increased cellular viability with no significant morphological aberrations were observed in processed specimen in Human Wharton's jelly derived mesenchymal stem cells (HW-MSCs). Higher resistance for platelet adhesion for the processed steel is explained by favorable electronic characteristics of the metal-oxide and short-range polar interactions at the cell-substrate interface. Higher stability of the metal-oxide on processed steel contributed towards reducing the metal-ion release and ensure better hemocompatibility.