TITLE:
3D Fluorescence Characterization of Synthetic Organic Dyes—Effect of pH
AUTHORS:
Leonard J. Soltzberg, Sarah Flynn, Vera Kirch, Richard Newman
KEYWORDS:
Fluorescence; Spectrophotometry; Dye Analysis; Textile Analysis
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.4 No.10,
October
11,
2013
ABSTRACT: The fingerprint character and high sensitivity of 3D
UV-vis fluorescence spectra offer special advantages for identification of
dyes in a museum or forensic setting. However, the extraction process is likely
to affect the pH of the medium and, in some cases, may alter the dye itself. We
report a study of 65 dyes extracted from wool fibers that are part of the
Schweppe Collection of Important Synthetic Dyes. The 3D fluorescence spectra of
the dye extracts at pH 1 and pH 14 are compared with the same dyes from the Schweppe solution
library, run under the same conditions, as well as with the 3D fluorescence
spectra of the dyes taken directly from the solution library without pH
control. This analysis leads to guidelines for the use of such spectra in
identifying unknown dye samples.