UV-Vis spectrophotometry was used to measure the solubility of disperse red 1 (DR1) dye in aqueous solutions, using different solvents and dispersants. The dye was quantified in water samples, and its interaction with calf thymus ds-DNA was investigated. The results showed that the commercial dispersant Fongranal® FB was suitable for the preparation of aqueous DR1 solutions. For the determination of DR1 in purified water, the limit of detection was 2.47 × 10-6 mol L-1, and the limit of quantification was 8.22 × 10-6 mol L-1. Percentage recoveries of 91.2 and 103% were obtained for DR1 concentrations of 3.00 × 10-6 and 40.0 × 10-6 mol L-1, respectively. The recoveries achieved for DR1 present in tap and river water were in the range 85.9-113%. The interaction of DR1 with calf thymus DNA was accompanied by hypochromic and hyperchromic effects, which were related to conformational changes and damage to the DNA double helix.
disperse red 1; textile dye; solubility; ds-DNA
