Feb. 26, the Elizabethtown College Department of Chemistry held a seminar led by Dr. Raychelle Burks. Burks is an esteemed associate professor of analytical chemistry at the American University in Washington D.C., and is well known for several prolific public appearances supported by prestigious scientific organizations and for advocating for various underrepresented groups in the STEM fields.
The work she discussed in this seminar followed the development of improved vapor-phase stains for cyanoacrylate (CA) ester processing of latent prints. Latent print development is still the number one way of identifying suspects and has been helping fight crime for over a century. CA processing of prints helps preserve them and is often preferred over other print gathering techniques such as dusting due to the ease, accuracy and versatility of the method.
Normally the technique of getting CA onto prints is known as “fuming” and can be done with CA alone on almost any non-porous surface. However, while CA fuming does work on virtually any surface, the results can often be hard to see, especially on white or silver pieces of evidence that match the natural color of the glue. Stains are employed to improve the clarity of prints on these more difficult surfaces. Current stains such as basic yellow 40 are effective but very expensive and toxic to the environment. These stains can also only be used once, so any that does not adhere to the CA must be disposed of without even contributing to the crime solving process. This is a significant issue as many crime fighting agencies often cannot afford to keep their stain supplies well stocked or do so by taking funding away from other important areas.
While leading a forensic chemistry class, Burks and her students realized the significance of this issue and worked to find a solution. While results were not instant, Burks and her students quickly found a variety of compounds that were likely to stain well. The constraints were rigorous, as the stains needed to effectively fluoresce under a handheld ultraviolet lamp, be more sustainable and cheaper than previous stains and most importantly, last over a period of at least six weeks. While it may come as a surprise to some, most forensic chemists must deal with a significant backlog of cases which often become a unique issue as all evidence degrades over time.
After some trial and error and, Burks mentioned with a laugh, “a lot of red solo cups,” the group managed to narrow it down to two major compounds that met all the criteria. The cups were not used for after lab partying, however, instead being used as the material onto which the CA and stain were fumed. They served as excellent media, having a variety of textures and colors that put the stains to the test while also being common in real crime scenes.
These two final compounds stained the CA a beautiful blue and met every criterion. Even with this group’s many recent successes, Burks and her team are by no means done with their research into CA stains yet. Currently, the group she is leading is also investigating additional staining candidates, expanding the original time trials and even trying to simplify the process to allow investigators more time to find those who are guilty.
Burks’ work in this field is a powerful reminder of the important role science plays in all areas of life, even in fighting crime.
If any members of the College are interested, their work was published Feb. 5 in the Journal of Forensic Sciences, which is linked here. Feel free to look through it for more information.
