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Detroit, MI, United States

Fraser D.,Lourdes University | Deroo C.S.,Detroit Institute of Arts | Cody R.B.,JEOL United States | Armitage R.A.,Eastern Michigan University
Analyst | Year: 2013

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. © 2013 The Royal Society of Chemistry. Source

Selvius Deroo C.,Detroit Institute of Arts | Armitage R.A.,Eastern Michigan University
Analytical Chemistry | Year: 2011

We present here a method requiring no sample preparation for direct identification of the organic dye compounds quercetin, indigotin, and alizarin in reference materials, in solution, and also in situ in dyed fibers by use of direct analysis in real time (DART) ionization and high-resolution time-of-flight mass spectrometry. Exact mass determinations on small samples of dyed textiles were completed in less than 1 min. With the ability to identify flavonoid, indigoid, and anthraquinone classes of dyes, this technique shows early promise as an additional analytical tool in the challenging analysis of organic dyes in rare cultural heritage materials and possesses the unique advantages of sensitivity and simplicity without the preparatory procedures required by other methods. © 2011 American Chemical Society. Source

Sutcliffe H.,Detroit Institute of Arts
Journal of the Institute of Conservation | Year: 2011

Re-imagining the way in which the Islamic art collection is exhibited at the Detroit Institute of Arts meant revisiting the ways in which it had been conserved and presented in the past. This article evaluates the way in which a collection of tiraz textiles from Medieval Egypt were conserved and displayed in the 1980s and how this informed a new conservation and display strategy for re-treating the textiles in 2010 using updated mounting techniques and materials. The textiles, which are predominantly fragments of clothing and shrouds, would have been excavated from a burial environment. Once accessioned into the museum's collection they were pressure mounted and framed, which led to them being viewed on the wall as pictures rather than as grave goods. This article will explore the collaboration between conservator and curator that led to a re-interpretation of the textiles to better connect them to their original context. Source

Li R.,Eastern Michigan University | Baker S.,Archaeological Historical Consultants | Selvius DeRoo C.,Detroit Institute of Arts | Armitage R.A.,Eastern Michigan University
ACS Symposium Series | Year: 2012

Cueva la Conga is the first limestone cave with paintings and modified speleothems found in Nicaragua. Dating of images made with inorganic pigments generally requires the presence of an organic binder. Chemical characterization of the organic material in the paint was undertaken using thermally assisted hydrolysis/methylation-gas chromatography-mass spectrometry (THM-GC-MS). Results show that significant quantities of organic material are present in the rock itself, precluding dating of the paints based on binders. Some of the inorganic paints, however, contain traces of charcoal, possibly from calcination of the iron oxide pigments to change their color. We have successfully dated charcoal from the paintings using plasma-chemical oxidation and accelerator mass spectrometry. This study considered the composition of the substrate when sampling of the rock art to be dated, and emphasizes the importance of rigorous sampling protocols in analysis of rock art. © 2012 American Chemical Society. Source

Geiger J.,Eastern Michigan University | Armitage R.A.,Eastern Michigan University | DeRoo C.S.,Detroit Institute of Arts
ACS Symposium Series | Year: 2012

We report here further developments in identifying organic dye compounds in botanical materials and natural fiber textiles using direct analysis in real time-time of flight mass spectrometry (DART-TOF-MS). This method requires little to no sample preparation, and analyses are completed in less than one minute. Analyses were performed on dyed cotton fibers from Traité des Matiéres Colorantes du Blanchiment et de la Teinture du Coton, a late 19th century treatise on dye chemistry, mordants, and dying techniques. Sandalwood and turmeric dyes were readily identified in the 128-year old cotton fibers by DART-MS with no sample preparation. Simple in situ hydrolysis and derivatization have the potential to expand the applicability of DART-MS to other dye compounds, including those in cutch and quercitron. © 2012 American Chemical Society. Source

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