Analysis of Disperse Dyes Using Liquid Chromatography/Linear Ion Trap Mass Spectrometry (LC/LIT-MSn) and Database Construction

Liquid chromatography/linear ion trap mass spectrometry (LC/LIT-MSn) was used to construct a database of disperse dyes. Fifty-three standard dyes were subjected to LC/LIT-MSn and characterized based on their mass spectra (MS, MS2, and MS3), values of λmax (maximum absorption wavelength in the UV-visible spectrum), and retention times. The results demonstrate that it is possible to reliably identify coexisting dyes that cannot be separated by LC or detected by diode array detection due to their low molecular absorption coefficients. In addition, the by-products included in the standard dyes were found to provide important information for the identification and discrimination of dyestuffs synthesized using different processes. The confirmation of the effectiveness of LC/LIT-MSn analysis in detecting small amounts of disperse dyes in this study shows its potential for use in the discrimination of dyed fibers obtained at crime scenes.