SPECTRAL SIGNATURES OF CHIRALITY AND CHIRALITY RECOGNITION

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A molecule is chiral, or said to exhibit "handedness", if its mirror image cannot be superimposed onto itself. Research into chirality and chirality recognition would be a pure scientific adventure if not for this important fact: many of the molecules produced by organisms exhibit a specific handedness. While one mirror image that fits the intended receptor in the organism is active, the other one may be inactive or may cause severe harm. There are, however, significant challenges in evaluating and finding solutions to these implications since the mirror images are so similar in many ways! My research program is dedicated to provide answers to two main aspects of these challenges through developments of 1) fast reliable methods for chirality determination and 2) rigorous chirality recognition models at the molecular level. Our original work on model chiral contact pairs and amino acid aggregates significantly furthers the goal of a rigorous description about chirality recognition at the molecular level. This proposal includes one major instrument development using the most advanced laser and mass spectrometry technologies. The innovative new tool will enable measurements of infrared signatures of chirality recognition in large bio-aggregates with specific mass/charge ratio both at room temperature and under ultra-cold condition, allowing unprecedented insights into the conformational conversion and recognition events. We have made important contributions in understanding how chiral molecules transfer chirality information to achiral molecules and in chirality determination of organic and inorganic compounds. We have successfully demonstrated the capability of a combined matrix isolation-vibrational circular dichroism (VCD) technique for following self-aggregation and chirality transfer events and for probing exotic chiral species that would otherwise be extremely difficult to study. To capitalize on our success, we will explore innovative new applications of two cutting-edge chiral detection techniques, i.e. a VCD and a Raman optical activity spectrometer (the first of its kind in Canada) to glycoproteins and chiral protected metal nanoparticles.