Chemical Society Seminar: Philippe Dauphin Ducharme - Molecular Monitoring in the Body using Electrochemical DNA-based Biosensors

Zoom link: https://mcgill.zoom.us/j/87597887772

Abstract:

Achieving continuous, real-time monitoring of a wide range of molecules directly in finger-pricked sized volumes of undiluted whole blood or directly in the living body would represent a significant feat in solving the paradigm of personalized medicine. At the moment, only two molecules can be monitored in this fashion: glucose and oxygen, thanks to the commercialization of the glucometer and the pulse oximeter. This limited offering of technologies ultimately impacts how we deliver and prescribe therapeutics to patients. It is common, for example, to be prescribed an antibiotic according to weight and age as opposed to how it is being metabolized in your body, which would inform on how to personalized dosing and increase positive treatment outcomes.

 

Motivated by this goal, we are developing electrochemical DNA-based (E-DNA) biosensors. These sensors are comprised of a redox-reporter-modified and electrode-bound aptamer “probe” that upon target-binding alters the kinetics with which electrons exchange to/from the redox reporter via binding-induced conformational changes producing an easily measured change in current when the sensor is interrogated using square-wave voltammetry. Because this class of sensor rely on a biology-inspired principle and an electrochemical signaling mechanism, E-DNA biosensors readily deploy in finger-pricked sized volumes of undiluted whole blood and can be threaded in catheters for real-time molecular measurements in the veins of anesthetized and freely-ambulating rodents. In this presentation I will be discussing the fundamentals of this class of sensor and how it can be used to perform continuous monitoring and delivery of vancomycin, a narrow-therapeutic window antibiotic often used as a last resort to treat bacterial infections. All these advances in developing E-DNA biosensors are aimed toward developing new analytical tools for personalized medicine while improving our understanding of drug metabolism.

Bio:

Dr. Philippe Dauphin-Ducharme completed his undergraduate degree in Chemistry at the Université de Montréal followed with a Ph.D. in Materials Chemistry at McGill University under the supervision of Prof. Janine Mauzeroll. His Ph.D. thesis focused on the development of scanning probe technique tools to monitor the corrosion of light weight alloys envisioned to reduce the weight of car bodies. Initially drawn in the field of DNA electrochemistry through a collaboration with Prof. Hanadi Sleiman, he then decided to take on a postdoctoral position at the University of California at Santa Barbara under the mentorship of Prof. Kevin Plaxco, where he participated in the development of new electrochemical DNA-based biosensors and their biophysical characterization. Hired as a new assistant professor in January 2020, Dr. Dauphin-Ducharme recently started his independent group at the Université de Sherbrooke where his research focusses on the development of new electrochemical biosensors, including DNA-based ones, for the real-time detection of molecules in complex matrices and directly in the body.