| AVS 61st International Symposium & Exhibition | |
| Conservation Studies of Heritage Materials Focus Topic | Thursday Sessions |
| Session CS-ThA |
| Session: | Conservation Studies of Heritage Materials 2 |
| Presenter: | Francesca Casadio, The Art Institute of Chicago |
| Authors: | F. Casadio, The Art Institute of Chicago F. Pozzi, The Art Institute of Chicago L. Chang, The Art Institute of Chicago D. Kurouski, Northwestern University S. Zaleski, Northwestern University N.C. Shah, Northwestern University R.P. Van Duyne, Northwestern University V. Rose, Argonne National Laboratory |
| Correspondent: | Click to Email |
In recent years, the scientific analysis of painted surfaces has made a giant leap forward. At the same time as innovative standoff macro-scale imaging modalities have been developed to deliver elemental mapping (using macro X-ray fluorescence spectroscopy) and molecular imaging (with Ultra-Violet/ Visible, Near Infrared, Mid-Infrared reflectance, fluorescence, and Raman imaging), our ability to probe local paint chemistries and mechanical properties at the nanoscale has grown exponentially. These recent developments have fundamentally changed the way conservators, curators and conservation scientists approach the study of works of art, leading to cutting-edge research on pigment degradation phenomena and enabling us to retrieve otherwise lost information on altered colors or hidden compositions that make up the original aspect of masterpieces.
This talk will present recent research employing high resolution nanoprobe synchrotron X-ray fluorescence (XRF) mapping of metallic impurities with 30 nm resolution in single grains of zinc oxide pigments used in early 20th century paints formulated for artists and other commercial uses and widely employed by Pablo Picasso (1881-1973). Such highly detailed chemical characterization of paints at the nanoscale opens the path to a better understanding of their historical fabrication and chemical reactivity.
For the characterization of organic molecules used in paintings Surface-Enhanced Raman Spectroscopy (SERS) has recently been developed into a robust, reliable and highly sensitive technique to detect and unambiguously identify minute quantities of organic colorants. SERS has seen the field of cultural heritage become one of its foremost research and application areas, resulting in improved analytical protocols applicable to several other fields such as pharmaceuticals and forensic analysis. In particular, our efforts to develop methods to identify more than one colorant on a single sample using combined Thin Layer Chromatography / SERS and microfluidics SERS approaches will be discussed. Pushing the envelope of in-situ SERS analysis, first results on the use of Tip-Enhanced Raman spectroscopy (TERS) for the high spatially resolved, highly sensitive and non-invasive investigation of dyes used on paper supports will be discussed and preliminary results presented. This first demonstration of TERS spectral acquisition directly on a paper substrate confirms the analytical potential of TERS to identify organic colorants in artworks with high sensitivity, high spatial resolution, and minimal invasiveness opening the way to future developments for the nano-scale mapping of organic constituents of works of art.