Adhesion characteristics of nano/micro-sized particles with dual ligands with different interaction distances

A particle-based delivery system is a promising future medical approach due to its multifuctionality and engineerability. Particularly, the efficiency and specificity of a particle can be controlled by conjugating a ligand to specifically interact with the receptor expressed on the target cell. To understand the binding mechanism of this particle based delivery system, the probability of adhesion for a dual ligand conjugated particle is analyzed by a stochastic model. Two different ligand-receptor pairs are considered where one is long with lower kinetic affinity and the other is relatively short with high kinetic affinity, which mimics the cell binding mechanism under hydrodynamic conditions. An optimized condition exists in order to maximize the probability of the particle adhesion. When the receptor ratio of long and short ligand-receptors is 2 : 8, the probability of adhesion can be maximized since the shear induced hydrodynamic torque can be minimized.