| Laser desorption mass spectrometry (LDMS) was evaluated as an analytical tool for the characterization of dyes and pigments found in ink and in artists' paints. Experimentation revealed that colorants can be easily detected on a variety of surfaces. Samples included ink from modern ballpoint pens, and ink found on stamps and on newspapers. However, the primary focus of this work rested in the LD mass spectrometric analysis of standard watercolor and oil paints.; Artists' paints are typically three component systems that include a colorant, vehicle, and resin. Currently, there are numerous analytical techniques available and used by art conservators to analyze these components individually, and a limited number are available for their analysis as mixtures. In the specific area of the identification and characterization of colorants, scientists have cited significant weaknesses in these methods. Consequently, there is a need for the development of new methods having the ability to identify more than one colorant in an impure mixture, and to provide molecular level information on both organic and inorganic colorants, simultaneously. Laser desorption mass spectrometry (LDMS) is an ideal candidate.; The LD mass spectra of numerous colorants will be presented, which demonstrate the potential for the development of LDMS as a sensitive analytical technique to be used in art conservation laboratories. The molecular level information generated in LD mass spectra can lead to the unambiguous identification of specific colorants present in an impure paint mixture. For example, the LD mass spectra of colorants used to create an illuminated page of the Koran from the 17th century, were obtained and the identified colorants offer insight into the authenticity of the document. Furthermore, sample size considerations and challenges typically encountered in the analysis of whole documents and paintings were identified and addressed. Proposed solutions were tested and the results suggest that the sampling challenges will not limit the use of LDMS as a tool in the field of art conservation. |
