Human whole blood (A) and PRP (B, C) were treated with G6.5-COOH-FITC, G7-OH-FITC, or G7-NH2-FITC, (100 μg/mL, final), saline, or ADP (5 μM, final). G7- NH2-FITC dendrimer treatment alone in significant platelet aggregation compared to no treatment (*, p<0.05) and G6.5-COOH-FITC and G7-OH-FITC (**, p<0.05) in whole blood. G7-NH2-FITC treatment significantly increases platelet aggregation in PRP (*, p<0.05) compared to no treatment as indicated by the increase in amplitude (B) and slope (C). The bars in panels A-C represent the mean ± SEM of three independent experiments.