The Ellenbarger Research Group


Negatively-charged particles, anions, comprise a major contingent of the most common chemical contaminants in drinking water, but research regarding anion sensors continue to be a growing area due to the physical and chemical difficulties associated with working with anions. Anions exhibit chemical sensitivity to pH and solvent choice, and anions exist in a variety of sizes and geometries that influence the weak interactions between the charged particles and their respective chemical environments. To this end, the Ellenbarger group at John Brown University is working to design chromogenic, urea-based receptors that selectively bind anions according to size, shape and energetic environment in aqueous solutions.

Urea is a common, naturally-occurring compound that interacts with anions through weak hydrogen-bonding interactions. While hydrogen-bonding interactions are weaker than a formal chemical bond, the magnitude and three-dimensional orientation of the hydrogen-bonding interactions between urea and the anion can be modified by incorporating one or more urea groups into a molecular framework. Much like a specific key is able to fit into and access a specific lock, several urea-based frameworks have been shown to exhibit specificity of anion binding according to differences in the size, orientation and energetic environment of the receptor framework. We seek to further explore this area by computationally considering the factors that influence anion binding in order to synthesize and characterize “tailored” receptors that target specific anions of interest.

We appreciate continued collaboration with and support through the Arkansas High Performance Computing Center (AHPCC)

The Research Group



Dr. Jill Ellenbarger graduated from Union University in 2011 with a B.S. in Chemistry. She then attended Texas A&M University, working for Kim R. Dunbar, and completed her Ph.D. in Chemistry in 2016. In August 2016, Jill began at John Brown University as an Assistant Professor in the Division of Natural Science. In addition to chemistry, Jill loves Jesus, her husband Michael, spontaneous adventures and ice cream!

Jaydee Edwards is entering her sophomore year at John Brown University studying chemistry and photography. In January 2017, she began this research project with Dr. Jill Ellenbarger and could not be more excited. Already in this time period, her understanding about the process of research, chemistry, and computational work has deepened. She is a lover of all things music, traveling, a good book, rainy days, hot tea, museums, tall mountains, the sea, and of course, chemistry.

Are you a current or incoming JBU student interested in joining our research team? Email Dr. E for more information!

The Latest Scoop

2017 Christian Scholars Foundation grant awarded to Jill Ellenbarger

Jill Ellenbarger has been awarded the 2017 Christian Scholars Foundation grant by Intervarsity’s Emerging Scholars Network to support her on-going computational research in designing color-changing compounds that detect harmful anions in drinking water.

July 2017: Summer Research is Underway! water

Through the support of the JBU Summer Scholars Fellowship, research is underway this summer in pursuit of anion-specific, colorimetric receptors.

January 2017: Welcome to the Group, Jaydee!JaydeePhotographer

With the new semester means new opportunities to do research with the newest (and only) research student - Jaydee Edwards! Welcome! Jaydee is also super gifted in photography and has contributed several new photos to the new research websites! Great job Jaydee!

JBU Summer Scholars Fellowship awarded to Jill Ellenbarger

Jill has been awarded a JBU Summer Scholars Fellowship, sponsored by the John Brown University Office of the President and Office of Academic Affairs. This three year summer fellowship will support her computational studies exploring colorimetric, anion sensors.

Contact us!

Questions? Comments? Please feel free contact Dr. Ellenbarger at