Polystyrene latex nanoparticles with different surface chemistries were incubated for 2 hours at 37 ˚C in 10 vol% FBS medium under shear flow conditions mimicking the median cubital vein (0.85 cm/s) and arteries (8.5 cm/s). The nanoparticles were then isolated using the centrifugation-resuspension method. In parallel, samples were treated under the same conditions and directly analyzed with PTA in the protein medium (Figure ). and) carboxylate-modified (8.5 cm/s) polystyrene latex nanoparticles measured after 2 hr incubation with 10 % v/v FBS at shear flow speeds of 0.85 cm/s and 8.5 cm/s, (mean and standard error, n=3 independent replicates and n=5 measurements per replicate). One-way ANOVA with Tukey's comparison test was performed to determine significant difference.