Microgels as Artificial Cells in Modeling the Flow of Neutrophils in the Pulmonary Microcirculation

In this study the role of passive mechanism for deformation of neutrophils, namely the effect of mechanical properties, was studied using microgels as model system. Both alginate-poly(N-isopropylacrylamide) interpenetrating polymer network (IPN) microgels and agarose microgels were synthesized in microfluidic device. The Young’s modulus and relaxation time of the IPN microgels were studied using atomic force microscopy equipped with a tipless cantilever. The lower limits of the elasticity found in this study were within the range of the elasticity reported for neutrophils. Agarose microgels were also prepared with a range of elastic shear modulus similar to neutrophils, and their flow under constrained geometries was studied. The flow profiles of four agarose microgel samples in a microchannel containing a constriction were analyzed. It was found that the stiffness of the microgels affected their velocity before, in and after the constriction.MAS