Mattanjah de Vries
Department of Chemistry and Biochemistry,
University of California, Santa Barbara
October 19, 2009
We use a combination of laser desorption mass spectrometry and double resonant laser spectroscopy to study the properties of and the interactions between compounds that may have made up the primordial soup on an early earth. IR-UV double resonance spectroscopy allows us to explore the photophysics as well as the hydrogen bonded structures of nucleobases. Amongst our findings is the observation that the structures of nucleobases and base pairs that occur in life as we know it today exhibit photophysical properties distinctly different from those of other possible structures. The excited state dynamics of these compounds depends on electronic structure in subtle ways. Prebiotic conditions presumably included more energetic UV irradiation than is the case today. Selective UV stability may have affected the eventual makeup of critical biomolecules and the photophysics we observe today may be a relic of a prebiotic past.