Motions Of Nanoscale Drug Carriers And Their Margination In Blood Flow

Recently,with the continuous development of nanotechnology,nanoscale drug carriers of different shapes and sizes have been produced,and targeted delivery of these nanoscale drug carriers in human body shows great advantages in treatment of various diseases,such as cancer.The efficiency of targeted drug delivery depends primarily on the ability of the drug carriers migrating in the blood flow toward the vascular endothelium and binding to specific sites.Therefore,it is very important for us to understand the margination properties of drug carriers and identify the factors that affect them.The main research in this paper focused on drug carrier motion and margination in a vascular microchannel under a pressure-driven flow.In this paper,the numerical model for red blood cells(RBCs)and drug carriers was an elastic spring model by which the shape and deformation of the objects in the flow was captured.The fluid-body interaction was accomplished by the immersed boundary method.We observed a waterfall phenomenon which was crucial for the carriers to migrate into the cell-free layer(CFL)near the vessel walls.We evaluated the effect of several factors,such as carrier size,the flow velocity,and carrier deformability on the margination properties of drug carriers(e.g.,liposomes)in the presence of red blood cells(RBCs).It was found that the smaller-sized drug carriers showed stronger marginalization characteristics.Secondly,with the increase of blood flow velocity,the drug carrier also showed a strong edge tendency.Finally,we found that when the blood flow velocity is small,the deformability of the drug carrier has no obvious effect on the margination.When a given blood flow velocity is large,it is found that a drug carrier that is prone to deformation has a better landing effect.The results of the numerical simulation in this paper are consistent with the experiments and results of other researchers.The present numerical investigation provides some physical insights of the margination of nanoscale particles,which must be considered in designing and choosing the optimum parameters of drug delivery systems.