Small molecule MALDI-TOF MS: Application to dyes and pigments

ANYL 249

Supicha Kridaratikorn, s.kridaratikorn@gmail.com1, LJ. Soltzberg, lsoltzberg@simmons.edu1, Amanda Hagar1, Anne Mattson1, and Richard Newman2. (1) Department of Chemistry, Simmons College, 300 The Fenway, Boston, MA 02115, (2) Scientific Research Lab, Museum of Fine Arts - Boston, 465 Huntington Avenue, Boston, MA 02115
MALDI-TOF mass spectrometry is valued for analysis of large molecules, such as synthetic polymers, proteins and nucleic acids. For certain small molecule analyses, the sensitivity, ease of sample preparation and relative tolerance of extraneous material are attractive attributes of MALDI-TOF. We have applied MALDI-TOF mass spectrometry to the analysis of dyes and pigments from small samples available from museum artifacts, falling in the mass range 200-1200 Da. Dye samples were prepared using an overlay method, and pigments were prepared using solvent-free grinding of the solid sample and matrix to form a micron-sized powder. By running both positive and negative ion spectra of each sample at the same laser fluence, the dye can be classified, and the presence of a strong molecular ion or simply-related fragment permits identification in most cases. Limit of detection is better than 100 fmol of analyte on the MALDI target. The figure shows the negative ion spectrum from a 1.2 fmol sample of Acid Blue 93; the [M-Na]- peak has S/N of 660 and the [M-H]- peak has S/N 286. We have identified dyes from single fiber samples of wool textiles.

 

General Posters
7:00 PM-9:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Analytical Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007