Grant: Research Tools and Instruments

A cornerstone analytical technique for characterizing the size and surface charge of colloids is dynamic light scattering (DLS). It is a key missing infrastructure at York University for numerous groups across Chemistry, Engineering and Biology researching on materials for analytical sciences, biomedical tools, vaccine development and environmental monitoring. DLS is the only in situ characterization technique that provides size and charge information of colloids readily. Colloids with different sizes, and charges under an electric potential, diffuse at different rates and yield random fluctuations in the scattering signal. Quantitative information, such as the hydrodynamic radius, zeta potential, and particle concentration, can be deduced based on the time scale of these fluctuations via autocorrelation signal processing. As a result, DLS is non-destructive and ideal for characterizing subnanometer to micron-sized particles in different solvents with minimal sample requirement. It is the only suitable equipment to address our needs in characterizing a diverse range of materials, from inorganic nanoparticles to polymers, lipid vesicles, microspheres and microplastics. We urgently need this equipment because our research, both in fundamental scientific inquiry and industrial collaborations, is facing bottlenecks and inefficiencies as we rely on qualitative observations instead of quantitative information. We often must proceed with experiments without verification of the targeted colloidal properties or biomolecular interactions, and we are only able to detect a problem downstream at a much later stage. The NSERC RTI will enable the acquisition of an in-house DLS instrument that will be fully utilized by at least 5 research groups plus numerous collaborators. It will enable equitable access to a fundamental materials characterization technique for all HQP.