Jonathan Ashby

  • Bertha Phillips Rodger Assistant Professor of Chemistry
Jonathan Ashby

Jonathan Ashby received his doctorate from the University of California, Riverside, where he used open-channel separation methods for the isolation of biomolecular complexes, such as proteins bound to nanoparticles and nucleic acid carriers in human serum. His postdoctoral studies at the University of California, Davis focused on affinity purification of DNA repair enzymes using non-cleavable lesion analogs.  Ashby’s research interests at Mount Holyoke involve the development of lower-cost, higher throughput assays that can act as alternatives to established methodology.

One of Ashby’s research projects involves developing tools for investigating protein-protein binding interfaces. In Ashby’s research group, amino-acid specific tags, such as fluorescamine, are used to tag the surface of a protein. As the protein-protein binding interface is shielded from the solvent environment, it cannot be tagged. Through comparison of the tagging locations on the single proteins and the protein-protein complex via mass spectrometry, identification of the binding interface is possible.

Another of Ashby’s research projects involves designing DNA aptasensors for small molecules. Aptamers are an attractive alternative to antibodies due to their ease of production, their ability to bind to targets under a wide variety of environmental conditions, and their ability to be developed for targets that antibodies cannot be developed for. High affinity aptamers can be selected from a large, randomized DNA library for a target through a process known as SELEX (Selective Evolution of Ligands via EXponential enrichment). The Ashby lab is looking at aptamer selection for neurodegenerative disease biomarkers. The selection process focuses on finding high affinity aptamers, where the aptamer undergoes significant structural change upon binding to the target. These aptamers can then be used in a variety of sensing platforms for point-of-care analysis or high-throughput screening.

Ashby teaches introductory chemistry and analytical chemistry. In his analytical chemistry course, one of the focuses is on science communication, such as learning how to give an elevator pitch, as well as learning how to effectively write short technical notes. In addition, another focus is on the critical comparison of different methods for chemical analysis.

Areas of Expertise

bioanalytical chemistry, separation sciences


  • Ph.D., University of California, Riverside
  • B.S., Trinity College

Recent Grants

Jonathan Ashby received a grant from the Undergraduate Analytical Research Program (UARP) of the Society for Analytical Chemists of Pittsburgh (SACP) for the project "Selection of structure-switching aptamers for usage in electrochemical biosensors." The project is for one year.

Jonathan Ashby received a grant from the Society for Analytical Chemists of Pittsburgh (SACP) for their 2020 Pittsburgh Conference Memorial National College Grant (PCMNCG) for the purchase of electrochemical instrumentation for integration into science coursework at Mount Holyoke College.

Recent Publications

Recent Honors

Jonathan Ashby acted as the planning chair for the annual meeting of the National Organization for the Professional Advancement of Black Chemists and Chemical Engineers (NOBCChE) from November 18-21, 2019 in St. Louis. There were approximately 600 attendees, with approximately 250 students who had supported travel to the conference.

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