Published in Analytical Chemistry, a collaboration between the Tallarek Group at Phillipps University in Marburg, Germany, and the Jorgenson Group describes the quantitative relationship between the bed morphology and the chromatographic separation efficiency of capillary columns packed with sub-2 μm particles, covering capillary inner diameters from 10 to 75 μm. The study focuses on wall effects and their impact on band broadening at increasing column-to-particle diameter (aspect) ratios. The researchers approach these complex effects by a morphological analysis of reconstructed column segments composed of several thousand particles that were imaged by confocal laser scanning microscopy.
Radial interparticle porosity profiles including wall effects are quantified through an integral porosity deviation, a scalar measure that proves to be a general descriptor of transcolumn porosity heterogeneity. It correlates with the associated transcolumn eddy dispersion, which dominates band broadening in the capillaries and is visualized in the plate height curves by a simple velocity-proportional term. This comprehensive approach identifies the packing structure features that contribute to decreased efficiency as reflected, e.g., in subtle variations of the wall effect at different aspect ratios, or a particle size-segregation effect in larger-diameter columns as a result of an increased number of packing voids near the wall–bed interface.
Laura Blue, a graduate student in the Jorgenson Group, has been chosen for membership in the Frank Porter Graham Honor Society. Named after the renowned former president of the University of North Carolina system, the FPGHS recognizes outstanding service provided to the University and community by graduate and professional students at Chapel Hill. Nominees are expected to be involved in activities above and beyond that which is required for their degree or position.
Laura is currently President of the Graduate and Professional Student Federation, founding member of Student Advocates for Graduate Education, on several committees such as the Tuition and Fee Advisory Task Force, the Graduate School Advisory Board, Student Fee Audit Committee, to only mention a few. Additionally, she is a coach for the New Hanover County Special Olympics, volunteers for Challenged Athletes, and They Will Surf Again, while also being a member of the UNC Water Polo Club and the Durham Masters Swim Team.