Effective shear augmented dispersion of solutes during nanoparticle assisted drug delivery in a microvessel

Abstract

The characteristics of shear augmented dispersion of solutes in blood flow are associated with conventional drug delivery systems. We investigate the dispersion characteristics of nanovectors due to the drug delivery procedure in a microvessel. The dispersion characteristics is based on the Taylor’s theory of shear dispersion where both molecular diffusion and convection take place. The rotation and aggregation nature of the red blood cells cause a two-phase flow nature at the microvessel for small radius of 50 μm which is modeled as yield-stress-based Herschel–Bulkley fluid. While the fluid of the no-particles zone at the peripheral region is considered as Newtonian fluid. Blood (mainly plasma) flow through the peripheral layer is documented by Darcy–Brinkman model. The permeability of the inner surface of the microvessel is subjected to a slip condition at the surface. It is observed that the slip constant, power-law index of Herschel–Bulkley fluid, rheological parameter, pressure gradient, yield stress and nanoparticle volume fraction are significantly related with velocity and dispersion coefficient. It is observed that yield stress and power-law index increase the velocity as well as effective dispersion coefficient at the plug region, while the permeability of the peripheral layer restricts the total effective dispersion coefficient.