Seminar by Jordan DEZALAY – Laboratoire PIIM

will take place on

Thursday, November 30th at 10:30

in the Salle du Conseil, service 322 of the PIIM laboratory (Campus St. Jerome)

Abstract: Understanding the photophysical properties of biomolecules plays an important role in understanding the stability of these molecules or in developing new applications (fluorescence microscopy, photodynamic therapy). Studying photophysical properties in biological medium is quite challenging, the presence of a complex environment (intra/intermolecular bonds, folding, hydration, complexation) can favour the formation of certain isomers, activate charge transfers or modify deactivation processes. To look at these properties several groups have developed electrospray coupled with cryogenic ion storage systems like in ISMO (Orsay) or PIIM. UV/Visible/IR lasers are sent into these traps to perform time- and energy-resolved photodissociation spectroscopy experiments. I will present some of the results obtained with these devices on relaxation processes in DNA bases. Recently, the two groups have developed double-cooled ion traps that produce ion aggregates with precise control over the nature and quantity of the surrounding medium. I will illustrate this progress with results obtained on small hydrated peptide aggregates. Finally, I will present a subject I want to pursue in my research in PIIM, radical ion spectroscopy the production of which is challenging in the gas phase. I will thus present an innovative study on DNA base radical cations.