Jump to main content
Jump to site search

Issue 16, 2013
Previous Article Next Article

Characterization of blood in an encrustation on an African mask: spectroscopic and direct analysis in real time mass spectrometric identification of haem

Author affiliations

Abstract

Prior to exhibiting an African Komo mask from the collections of the Detroit Institute of Arts, a multianalytical approach was undertaken to characterize the flaking encrusted coating on the surface of the mask. Preliminary XRF and FTIR examination of the coating on the Komo mask revealed the presence of significant quantities of iron and protein, possibly indicating the presence of blood. Raman spectroscopy showed evidence for the porphyrin structure of haem as well. To confirm that blood was indeed present in the coating, we developed a novel method for identifying the haem moiety from blood by use of in situ methylation and direct analysis in real time mass spectrometry (DART-MS). Following a denaturing step with formic acid, the resulting solution was combined with an excess of phenyltrimethylammonium hydroxide to promote desorption, applied to a melting point tube, and placed into the direct analysis in real time ion source gas stream at 550 °C. The permethylated haem ion (m/z 644.208) from myoglobin, haemoglobin, fresh blood, and blood aged in the laboratory for 10 years was readily observed above the background. By the described DART-TOF-MS method, permethylated haem was positively identified in the mask coating, confirming the presence of blood. This method has obvious utility in forensic science beyond that for identifying blood incorporated in cultural heritage materials.

Graphical abstract: Characterization of blood in an encrustation on an African mask: spectroscopic and direct analysis in real time mass spectrometric identification of haem

Back to tab navigation

Publication details

The article was received on 31 Mar 2013, accepted on 11 Jun 2013 and first published on 11 Jun 2013


Article type: Paper
DOI: 10.1039/C3AN00633F
Citation: Analyst, 2013,138, 4470-4474
  •   Request permissions

    Characterization of blood in an encrustation on an African mask: spectroscopic and direct analysis in real time mass spectrometric identification of haem

    D. Fraser, C. S. DeRoo, R. B. Cody and R. A. Armitage, Analyst, 2013, 138, 4470
    DOI: 10.1039/C3AN00633F

Search articles by author

Spotlight

Advertisements