Spectrophotometric characteristics and assay of pure pyronin Y.
The spectrophotometric characteristics of analytically pure pyronin Y have been investigated. Addition of metal ions (Fe3+, Zn2+, and Mg2+) and of dextrin were shown not to influence the absorption characteristics. The composition of the solvent strongly influenced the value of the extinction coefficient. Aqueous ethanolic solutions with a content of about 50% ethanol gave higher epsilon-values than those found for more concentrated ethanol solutions. The difference can be explained by the existence of a solvent-solute complex in the less concentrated ethanol solutions. A new spectrophotometric assay is proposed using the epsilon-value 11.7 X 10(4) lmol-1 cm-1 found in aqueous ethanol (52%) as standard.
D007501:Iron / Q000032:analysis; D011754:Pyronine / Q000032:analysis*; D012997:Solvents; D013053:Spectrophotometry; D014966:Xanthenes / Q000032:analysis*; D015032:Zinc / Q000032:analysis
D012997:Solvents; D014966:Xanthenes; D007501:Iron; D015032:Zinc; D011754:Pyronine