Modelado numérico de la sección eficaz diferencial de dispersión entre una nanopartícula y un eritrocito

Abstract

Nanoparticles are widely used in imaging studies as contrast agents, as well as in cancer treatments for drug delivery and release in tumors and surrounding areas, and in hyperthermic therapies. When injected into the bloodstream, the main factor that reduces the efficiency of nanoparticles in therapies or treatments is their dispersion and migration towards vascular walls, primarily due to their interaction with blood components, with erythrocytes being the main scattering center. This paper proposes a numerical model for the collision kinetics between a nanoparticle and an erythrocyte, aiming to obtain the differential scattering cross-section. The viscoelastic characteristics of the erythrocyte membrane were emphasized to study the interaction within the collision interval using classical molecular dynamics. The kinetic and energetic behavior of the interaction was described considering the drag force exerted by the erythrocyte surface on the nanoparticle and the viscoelastic force associated with a nonlinear displacement of the nanoparticle. Additionally, an analytical model based on trajectory vectors before and after collision, associated with the position and velocity vectors of the nanoparticle, was proposed. This approach resulted in obtaining the scattering angle profiles and quantifying the differential scattering cross-section between the particle and the erythrocyte. The findings demonstrated that dispersion depends on the biconcave and symmetrical geometry of the erythrocyte, as well as the nanoparticle's kinetics.