Blood is a collection of similar specialized cells, namely, red blood cells (RBCs), white blood cells (WBCs), and platelets. The membrane of RBC comprises a network of filamentous proteins forming the cytoskeleton and a phospholipid bilayer. Several techniques have been developed to measure the biomechanical properties of an RBC membrane. There are two general widely used RBC membrane models, that is shell-based model and spring-based model. Numerical simulations of RBCs in micro channel flows have increasingly become very important tools in providing insight to the physics of the flows. There are three major broad types of numerical methods extensively used in RBC simulations: mesh-based methods particle-based methods hybrid mesh-particle methods. The nanoparticle dispersion rate is strongly influenced by local disturbances in the flow due to RBC motion and deformation. The chapter summarizes the advantages and disadvantages of the particle-based methods in RBC simulations.