Characterization of the effects that 14 day-exposure to AuNP1.5 (0.6 µg/mL), AuNP4 (10 µg/mL), and AuNP14 (10 µg/mL) has on the capability of hESCs to passively differentiate into cells of the three germ layers. (A, B) Quantitative RT-PCR expression analysis for the ectodermal markers (NCAM) (A), and (NESTIN) (B). (C–E) Quantitative RT-PCR expression analysis for the mesodermal markers (BRACHYURY) (C), (PITX2) (D), and (LEFTY) (E). (F, G) Quantitative RT-PCR expression analysis for the endodermal markers (NODAL) (F) and (AFP) (G). At the concentrations examined, exposure to AuNPs did not affect the in vitro pluripotency capabilities of hESCs. Histogram values represent means and error bars represent 95% interval confidences (p > 0.05; n = 3, one-way ANOVA and Kruskal Wallis tests).