Microrobotic Locomotion in Blood Vessels: A Computational Study on the Performance of Surface Microrollers in the Cardiovascular System

Surface microrollers have emerged as a promising microrobotic platform for navigation in the circulatory system as future drug/gene delivery applications. The circulatory system comprises various vessels with different dimensions, blood flow velocities, and flow regimes. Therefore, the performance of surface microrollers would vary in blood vessels. Herein, the performance of surface microrollers, with diameters between 5 and 50 μm, inside vessels of the systemic circulation including veins, venules, capillaries, arterioles, and arteries is investigated with computational fluid dynamics simulations. The simulation environment consists of a simplified fluid with the viscosity and density of blood, without red blood cells, in a cylindrical pipe. The microrollers demonstrate successful upstream locomotion ability in veins and partially in arteries but fail to perform in smaller blood vessels due to significant confinement and flow effects. Overall, the results presented here establish a preliminary result for the future in vivo use of surface microrollers.