Iron-oxide nano-particles effect on the blood hemodynamics in atherosclerotic coronary arteries

Abstract

The use of nanomedicine for diagnosing, treatment and/or monitoring of diseases can change the viscosity of blood and lead to different pressure drop and wall shear stress in an atherosclerotic coronary artery. In the present study, in a typical atherosclerotic coronary artery, the effect of iron-oxide nano-particles (Fe3O4) on the blood hemodynamics was studied. Dynamic viscosity as a function of the nano-particles’ volume fraction in the blood was predicted through a nonlinear equation, and Herschel–Bulkley model was used to model the shear stress. For the non-Newtonian fluid, the equation of motion was solved for a tapered tube of different diameters. Experimental design based on Taguchi approach and Response Surface Methodology (RSM) was employed to study the effect of different hemodynamic parameters on the pressure drop. It was shown that increasing the nano-particles’ volume fraction (ranging from 0 to 0.5%) increases the pressure drop to a maximum amount, and a further increase in the volume fraction up to 2% leads to a decrease in the pressure drop. Furthermore, the shear rate at the wall increases with the volume fraction of the nano-particles to a maximum value and then slightly decreases. It was observed that, to some extent, injection of nanoparticles especially into narrow blood channels such as atherosclerotic coronary arteries could variously affect the blood flow pressure drop. These findings suggest that for patients with the atherosclerotic problem the nanomedicine injection dose can be important, which could be encouraging from practical and biomedical engineering points of view.