The xanthene dyes Rose Bengal, erythrosin B, eosin Y, and fluorescein, the reagents 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and 1-octanol, were purchased from Sigma-Aldrich and were used without further purification.
The chemical structure of the four xanthene dyes Rose Bengal, erythrosin B, eosin Y, and fluorescein studied in this work (Figure 1) was also investigated with Density Functional Theory (DFT) as implemented in Gaussian 03 package .
Thus, the results of the photooxidation of uric acid and determination of the [IC.sub.50] experiments converge to the following order of photodynamic efficiency for the dyes studied here: Rose Bengal (RB) > erythrosin B (EB) > eosin Y (EY) > fluorescein (FL).
Sehn et al., "Photodegradation in micellar aqueous solutions of erythrosin esters derivatives," Applied Spectroscopy, vol.
The xanthene dyes: Rose Bengal (RB), erythrosin B (EB), eosin Y (EY), and fluorescein (FL).
The adverse effects reported by others coupled with the chemical similarities among tartrazine, sudan I, erythrosin B, and estradiol-17[beta] (E2) (Fig.1) led us to ask whether these colorants were potential EDCs,specifically xenoestrogens, acting not at pharmacological concentrations but rather within physiological concentrations.
Porcine insulin, EDTA, charcoal-dextran, E2 (E8875-IG), tamoxifen (T5648-1G), tartrazine (T0388-100G), erythrosin B (E9259-5G) and sudan I (103624-25G) were purchased from Sigma-Aldrich, St.
After 24 h, the medium was changed to phenol red-free RPMI 1640 supplemented with 5% CS-FBS and 2% AbAm and either control (vehicle only), E2, tartrazine, erythrosin B, or sudan I (0.001, 0.01, 0.1, 1, and 10 nM).
After 6 h, the transfection medium was replaced with phenol red-free RPMI medium 1640 plus 5% v/v CS-FBS and either control (vehicle only, E2 (0.1 nM), tartrazine (0.1 nM), erythrosin B (0.01 nM), or sudan 1 (1 nM), in triplicate.
Proliferative Effect of Tartrazine, Erythrosin B, and Sudan I in T47D Cells--Cell proliferation assays measure the proliferative effect of estrogen or xenoestrogens on estrogen-responsive cells in a hormone-stripped medium (Soto et al., 1995).