2017 Volume 29 Issue 2 Pages 49-55
Thrombus formation on biomaterial surfaces with microstructures is complicated and not fully understood. We assumed that the micro-stagnation generated around microstructures is one factor to enhance thrombus formation. In our prediction, the micro-flow around microstructures causes blood components to adhere physically in a low Reynolds number region. The objective of this study is to investigate the micro-flow around three-dimensional micro-geometric structures and the aspects of physical adhesion affected by the micro-flow. Flow simulation and quantitative assessment of adhesion rates around micro-columns was conducted as a basic study. The particle pathlines and average shear rate around a column were calculated through computational fluid dynamics analysis. The simulation showed that low shear rate distribution caused by flow-stagnation is generated around a column, even if it is in micro-flow in a low Reynolds number region. Physical adhesion tests using micro-beads showed that the average adhesion rate around the column was higher than that in the neighboring plane area. A low shear rate region generated by microstructures may increase the potential for adhesion of substances, which enhances thrombus formation even when the scale of flow is of the order of micrometers.
