Vibrational spectrochemical imaging studies of materials from macro to nanoscale

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Critical chemical interactions occur at the nanoscale but have impact at every dimension. My students and I tackle the challenges inherent in imaging the chemistry of materials at length scales from one thousandth to one billionth of a meter, using model systems for proof of principle. Specifically, we probe the chemical composition of matter with visible and infrared light, using a technique called vibrational spectroscopy. With this program, I strive to be a world leader in vibrational spectrochemical imaging, training young scientists in groundbreaking techniques to solve puzzles related to important materials and environmental issues. My short term objectives represent real-world problems that span the nano to macro resolution scale, in new materials made from renewable resources to the impact of climate change on Arctic sea ice diatoms, key members of the marine food web. We take established principles of vibrational spectroscopy to the scientific frontier, using best diffraction-limited optics, our newly-patented accessory for infrared tomography, and super-resolution techniques that break the infrared diffraction limit. We devise novel methods to retain native molecular architecture, allowing us to elucidate localized chemistry and make accurate interpretations of this previously inaccessible micro and nanoscale data.***In one branch of my program, we use spectrochemical imaging to identify chemical changes in single-celled microorganisms under normal and stress conditions. Why? We can discover how nutrient and light levels, and community interactions affect Arctic sea ice diatoms, key to predicting their likely responses to global climate change and decreasing sea ice. We can learn how the cell wall ultrastructure of Candida albicans is affected by external stimuli, especially antifungal treatments. ***In the other branch, we analyze natural and synthetic fibres at the micro and nanoscale. We aim to maximize the added-value of post-harvest waste-stream fibre, a renewable resource, and improve production quality of bio-inspired synthetic silk materials that depend on molecular composition, orientation and conformation. We will better understand the self-assembly of collagens, biomolecules that perform essential functions in the healthy body and are basic to tissue engineering materials. Finally, we will aid the design of new contact-active self-disinfective surfaces, a disruptive technology created to prevent cross-infection in hospitals and contamination of food during processing or packaging. ***Our spectroscopic capabilities will accelerate completely new avenues of discovery. My students, skilled in these techniques, will be able to connect consequences from the molecular to macroscopic length scales, and be ready to contribute to the advancement of fundamental knowledge, aiding environmental, health and advanced manufacturing initiatives in Canada.