SCIART: Microanalytical and Non-Invasive Approaches for the Investigation of Works of Art by Surface-enhanced Raman Spectroscopy (SERS)

Metropolitan Museum Of Art, New York NY

Investigators

Abstract

With support from the Chemical Measurement and Imaging Program (via the SciArt solicitation), Drs. Marco Leona of the Metropolitan Museum of Art and John Lombardi of CUNY are devising means of identifying the materials present in works of art - complex assemblages of inorganic and organic materials, often with unknown histories. The work is essential to understanding the history and improving the conservation of artworks. The problem is challenging because many materials of interest (e.g., markers for provenance, attribution, and use history) are present in very low concentrations and/or are affected by degradation processes. Strict sampling limitations further complicate the undertaking. The team is adapting surface-enhanced Raman spectroscopy (SERS) for the identification of organic colorants, an important class of artists' materials found in textiles, paintings, and other polychrome works of art. Specifically, they are developing sensitive and reproducible SERS substrates and new sample preparation methods, and using a broadband tunable laser to enable resonant excitation for increased sensitivity. They are investigating computational modeling in parallel with experimental adsorption measurements to address important problems affecting SERS, such as variations in response among closely related dyes and the influence of interfering compounds. The high-sensitivity non-destructive techniques being developed should have applicability beyond the confines of cultural heritage research, in areas such as biochemical, pharmaceutical, environmental, and forensic, and homeland security. The increased understanding of the SERS phenomenon will be helpful in elucidating the relative importance of electromagnetic and chemical contributions to the SERS mechanism. The work will thus have broad impact through improved understanding and conservation of works of art and cultural heritage; enhanced cross-disciplinary research training for undergraduate, graduate, and postdoctoral chemists with case studies from art conservation and art historical studies; and science outreach through inclusion of scientific results in museum publications and public programs.