The experimental conditions were an aqueous suspension (4L) containing 100 mg [L.sup.-1] of the photocatalyst and 125 mg of the dye (P4R or New Coccine
, Dye content 75%, Sigma-Aldrich).
The selectivity of the proposed method was studied with the same concentration of other colorants including Tartrazine, New Coccine
, Amaranth, Allura Red, and Brilliant Blue.
Azo dyes, a class of synthetic organic dyes that provide more vivid colors to foods, have in their composition a naphthalene ring bonded to a benzene ring by an azo bond (N = N), and the Ponceau 4R, also known in the food industry as New Coccine
Red and Food Red, is a representative of this class (PAN et al., 2011).
Among them, Amaranth, Allura Red, New Coccine
, and Tartrazine induced DNA damage in the colon.