Prof Siva Umapathy

MoSE 3201A
Friday, January 12, 2018 - 11:00am to 12:00pm

Time and space resolved vibrational spectroscopy: applications to Chemistry and Biology

Recent advances in laser and detector technologies have facilitated research at the frontier of chemistry and biology. In terms of time resolution (femtoseconds) we are able to explore the molecular structural dynamics at the same time scale as the vibrational time period. Understanding bond specific vibrational energy redistribution and relaxation of excited molecular states and also their bond specific structural dynamics were not accessible at femtosecond time resolutions due to the inherent band width restrictions present in femtosecond laser pulses. However, in recent times, study of the third order non-linear susceptibility response of a system using stimulated Raman scattering processes leads to observation of evolution of vibrational structures in femtosecond time scales.  We would show examples of energy migration and coherent oscillation of coupled vibrational modes which provide information on early time response of a molecular system on excitation.

In terms of spatial resolution, the coherent nature of light leads to spatial resolutions much less than the single biological cell dimensions.  We would show case the Raman and Infrared micro-spectroscopic applications to biology and medicine. In particular, applications to drug-cell interactions, model system studies to explore critical diseases, stem cells, and development of early diagnosis based on biochemical vibrational frequency markers would be presented. Finally, a new methodology for three dimensional Raman imaging would also be discussed.

Contact Information: 

Rob Dickson

(404) 894-4007

Map of Georgia Tech

School of Chemistry & Biochemistry

901 Atlantic Drive Atlanta, GA 30332-0400

(404) 894-4002 (phone) | (404) 894-7452 (fax)