Final Thoughts

Hello Everyone!

Reflecting on my research goals for the summer, I have now completed a library of spectra with surface enhanced Raman spectroscopy of a collection of organic yellow dyes and pigments.  Now, I could hypothetically identify an unknown organic yellow colorant in a historical oil painting by sampling only a fraction of what would be needed for other, less sensitive techniques.  The only dye I was not able to identify with SERS was gamboge, which is made of a resinous material that is insoluble and very difficult to work with.  However, gamboge was frequently used in historical paintings, so it is important that I am able to develop a pre-treatment strategy that works for it in the future.  So far I have been able to solubilize it in a solution of ethanol and water, but this treatment has not yielded clearer spectra so far.

I also have samples from the Portrait of Mrs. Nelson and in the future I will hopefully be able to distinguish both the organic and inorganic yellow colorants used in this painting.  Also, to complete a thorough analysis of the painting, I will identify samples of blue and yellow from the painting by polarized light microscopy, FTIR analysis, and SERS.  Once I examine the samples with as many techniques as possible, I have a better chance of properly identifying them without damaging the samples or taking too large of a sample from the painting.  Another of my future goals involves figuring out a way to perform SERS on a cross-section from a painting.  Ideally, this would allow us to identify what materials were used on each successive layer of paint.

Now that summer research has come to an end, I want to thank Dr. Kristin Wustholz, Shelley Svoboda, the Colonial Williamsburg Foundation, and the Charles Center for this opportunity and the Chappell Fellowship I received.


  1. Lauren Greene says:

    Hi Hannah!
    I’m envious that you were able to work with CW for your project! It must have been pretty exciting to work directly with the art. It sounds like you had a good summer of research and I hope your future projects go well!