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The department of chemistry is really proud of graduate students Zi Wang, from the Ariya group, and Kayrel Edwards, from the Barrett group, for being award two first place award for the oral presentations they delivered at the virtual on August.

Zi Wang presented her talk in the Biogeochemistry Theme in the symposium entitled Environmental chemistry and Sustainability: a Health intake: Environmental Pollutants in Air, Water, Food, and their Removal. In the awarded oral presentation entitled ‘Advances in Ultra-Trace Analytica Capability for Micro/Nanoplastics and Water-Soluble Polymers in the Environment’, it has been demonstrated that recyclable in-laboratory built nanostructured laser desorption/ionization time-of-flight mass spectrometry (NALDI-TOF-MS) can provide ultra-trace (picogram) detection capabilities for soluble polymers and micro/nano-plastic fragments in water and snowmelts, without sample pre-treatments. This work opens the door to further accurate identification and trace quantification of micro/nano-plastics in diverse environmental and biological matrices, producing key information in the investigation of the fate and transformation pathways of micro/nano-plastics in the Earth’s ecosystem. This work was supported by the Natural Science and Engineering Research Council of Canada (NSERC) and National Research Council (NRC) and published in .

With her oral presentation entitled 'Controlled disassembly of cellulose-based thin films using light', Kayrel Edwards won the award in the Biodegradable and Bio-Derived Polymers symposium. As traditional disposable plastics have now become a global environmental problem due to their overuse, non-degradability, and toxicity, Kayrel works on a project focused on preparing functional materials from natural polymers whose disassembly can be controlled using blue/green light. A proof of principle using azo-cellulose layer-by-layer thin films was demonstrated for the first time. Two water soluble components were combined to fabricate a water-resistant film. The disassembly of the films was triggered using blue/green light due to the trans-to-cis isomerization of the azobenzene, confirmed by UV-Vis spectroscopy and Raman spectroscopy. These materials have the potential to be disassembled in a controlled manner and recycled to be used as 2nd generation materials.