Tuesday, November 14, 2017

URSP Student Allison O'Neill Examines the Characterization of Humic Acids by High Performance Liquid Chromatography

As a freshman I applied to be a lab assistant for a graduate researcher working in Dr. Foster’s lab. However, I quickly became intrigued with the research team’s studies of humic substances. After many conversations with Dr. Foster I was able to write a proposal to OSCAR, focusing on the extraction of humic acids from local surface waters in order to subject them to further characterization. I was able to develop, refine, and build upon this extraction process throughout my sophomore year and subject my samples to fluorescence spectrophotometry. However, I was still unable to further concentrate my samples to be purely humics and was interested in quantifying their weight via mass spectrometry. This led me to apply to OSCAR again, focusing on concentration methods and molecular weight.

My typical week consists of going into the lab at the Potomac Science center. I filter the samples, run them through my extraction column, and elute them out. From there we have developed a method to desalt the eluted samples and then the water has to be evaporated off. Another method we have developed uses toluidine blue, a dyeing agent, that will bind to the humics, so that we can run the samples through a Spec 20 and determine the parts per million of humics in the sample of water collected. Lastly, we have yet another method still in the works that uses a high performance liquid chromatography column. This method will allow us to gain more insight to the size of the compounds.

Being able to perform this research has been such an incredible opportunity! I have presented my research at numerous conferences. The methods that I am using are a real life application of what I have learned in my classes, but in most cases, the methods that I am using have gone past what I have learned in my courses. I feel more prepared for a career in this field, since I have had so much experience working in a lab.