Dr. Jennifer Dionne

 

    In a lab at Stanford University, Dr. Jennifer Dionne (left) and Loza Tadesse (right) are diligently studying how to use surface-enhanced Raman spectroscopy to identify bacteria in their natural habitat. Dr. Jennifer Dionne received her Ph.D. in Applied Physics at the California Institute of Technology and B.S. degrees in Physics and Systems & Electrical Engineering from Washington University in St. Louis. Her research focuses on developing nanophotonic methods to observe and control chemical and biological processes as they unfold with nanometer scale resolution. This year, she was promoted to Senior Associate Dean of Research for Platforms/Shared Facilities at Stanford. Loza Tadesse, one of Dr. Dionne's students, is a Ph.D. candidate in bioengineering. Before attending Stanford, Tadesse was a medical student at St. Paul Hospital Millennium Medical College in Ethiopia. 

   When using surface-enhanced Raman spectroscopy (SERS), researchers place a bacterium near a metallic surface. Then they shine a laser on the surface plasmons in the metal. The resonant interactions increase the Raman scattering from the bacterium’s cellular material. The boosted scattering signature allows the researchers to identify the bacterium and its molecular structure. This technique has been confirmed for dry samples, which requires the samples be prepared; however, bacterial cells live in water. Tadesse and Dr. Dionne, along with their colleagues, have developed a protocol for liquid SERS measurements. This may allow for real-time testing of the susceptibility of bacteria to various drug treatments. A technique such as this one could speed up the time it takes to create and perfect antibiotics.

https://physicstoday.scitation.org/do/10.1063/PT.6.1.20201002b/full/

https://profiles.stanford.edu/jennifer-dionne

https://profiles.stanford.edu/loza-tadesse