Toxicity effects of synthesized CdSe QDs before and after SGF treatment utilizing Live/Dead assay. Attached live (A) and dead (B) Caco-2 cells after dosing with in-house synthesized CdSe QDs. Attached live (C) and dead (D) Caco-2 cells after dosing with SGF-treated in-house synthesized CdSe QDs (concentrations were influenced by dilution during SGF treatment). Data are expressed as the mean ± SE from three separate experiments using cells of different cultures. Statistically significant difference in attached cell number (either attached live cells or attached dead cells) between a certain QD dose and all other doses within the same type of QD are indicated by an asterisk (*) (p < 0.05), Statistically significant differences in attached cell number (either attached live cells or attached dead cells) between a certain type of QD and all other types of QD within the same dose are indicated by a pound symbol (#) (p < 0.05). The over bar indicates there is no statistically significant difference between connected groups.