Most nanoparticle formulations are intended for parenteral administration and will result in administered nanoparticles experiencing shear flow conditions in the circulatory system . Here we examined the role of shear flow conditions in nanoparticle parameters following treatment with protein containing media, mimicking arterial and venous blood flow. Our findings showed that under flow conditions, total surface adsorbed protein content under flow was equivalent to the same levels seen following a 24-hour incubation with end over end rotation conditions. The composition of proteins adsorbed onto nanoparticle surfaces were found to significantly vary depending on nanoparticle surface chemistry, but shear flow did not change the number of bands across particle samples (Figure ).