Margination and adhesion of micro- and nanoparticles in the coronary circulation: a step towards optimised drug carrier design.

Obstruction of left anterior descending artery (LAD) due to the thrombosis or atherosclerotic plaques is the leading cause of death worldwide. Targeted delivery of drugs through micro- and nanoparticles is a very promising approach for developing new strategies in clot-busting or treating restenosis. In this work, we modelled the blood flow characteristics in a patient-specific reconstructed LAD artery by the fluid-solid interaction method and based on physiological boundary conditions. Next, we provided a Lagrangian description of micro- and nanoparticles dynamics in the blood flow considering their Brownian motion and the particle-particle interactions. Our results state that the number of spherical particles migrating towards the region of lumen with potential of thrombus existence (PTE) rises by increasing the particle size. Also, an optimum scope of particle size in which the adhesive probability parameter reaches its maximum was determined. We acquired an optimum scope for a specific degree of particle sphericity in which the thrombus surfaces experience the maximum density of interaction with particles. We learned that the ligand-receptor mechanism-based drug carriers are better choices for treating LAD arterial diseases when the addressees are patients with low haematocrit-related diseases. While due to the amount of shear stress exerting on the diseased area, generally exploiting nanoshear-activated drug carriers would be the more effective option when it comes to the thrombolytic therapies of patients with high haematocrit-related diseases.