Transient Electric Birefringence for the Characterization of Cellulose Nanocrystals and Tobacco Mosaic Virus

The development of a transient electric birefringence (TEB) apparatus for macroparticle characterization is herein discussed. The experimental difficulties encountered were related largely to poor data resolution. Misalignment and strain birefringence in optical components further complicated results. Improved data digitization methods were developed, and precise mathematical models were derived in order to characterize stray birefringence. These were discussed in context of published linear estimations for TEB.;A size exclusion technique specific to cellulose nanocrystals was developed using liquid crystal phase separation. The size distribution differences for distinct liquid crystal phases were determined from diffusion coefficients measured with the TEB apparatus. Size distributions were compared to standard microscopy sizing techniques, specifically AFM and TEM.;Methods for absolute size distribution determination from measured diffusion coefficients were considered and attempted using a simplified method of linear inverse theory. We conclude that absolute size distribution solutions for inverse theory will require a significant reduction in experimental noise, as well as the development of more accurate mathematical models.