WCDG meets monthly September to May and typically on the 3rd Wednesday of the month, unless otherwise noted. Meetings are public and include a light dinner & social hour followed by a speaker.
Email us at washchrom@gmail.com. Follow us on LinkedIn.


March Meeting

Wednesday, March 14, 2018
USP, 12601 Twinbrook Pkwy, Rockville, MD 20852
6:00 PM dinner & social
6:55 PM Sarah Gao, 2017 Student Poster Winner
7:00 PM featured presentation

Speaker:
Mark R. Schure, Kroungold Analytical, Blue Bell, PA
Title: Multidimensional separations in three and higher dimensions

Abstract: Two-dimensional liquid chromatography is fast becoming an accepted technique in the analysis of complex molecules from biological, environmental, pharmaceutical and industrial sources. As these techniques mature we have been asking questions which look into higher dimensionality separations. These include three and higher dimensions. To discuss these types of separations, one has to have a measure of how well these separations work. Orthogonality metrics (OMs) for three and higher dimensional separations are proposed as extensions of previously developed OMs, which were used to evaluate the zone utilization of two-dimensional (2D) separations. These OMs include correlation coefficients, (fractal) dimensionality, information theory metrics and convex-hull metrics. In a number of these cases, lower dimensional subspace metrics exist and can be readily calculated. The metrics are used to interpret previously generated experimental data. Experimental datasets are derived from Gilar’s peptide data, now modified to be three dimensional (3D), and a comprehensive 3D chromatogram from Moore and Jorgenson. The Moore and Jorgenson chromatogram, which has 25 identifiable 3D volume elements or peaks, displayed good orthogonality values over all dimensions. However, OMs based on discretization of the 3D space changed substantially with changes in binning parameters. The Gilar data, which in a previous study produced 21 2D datasets by the pairing of 7 one-dimensional separations, was reinterpreted to produce 35 3D datasets. These datasets show a number of interesting properties, one of which is that geometric and harmonic means of lower dimensional subspace (i.e., 2D) OMs correlate well with the higher dimensional (i.e., 3D) OMs. This talk will use a minimum number of equations and will highlight the experimental difficulties which crop up with higher dimensional separations. We will discuss the extent to which 3D separations will yield better results than 2D separations and how simple separations in the first dimension, such as trapping, can perform critical fractionation (class separations) in a small amount of time.

Bio: Mark Schure has worked in separation science for over 35 years in industry and academics. Over a 28 year period he has worked for Digital Equipment Corporation, the Rohm and Haas Company and The Dow Chemical Company. Dr. Schure has been an Adjunct Professor in the Department of Chemical and Biomolecular Engineering at the University of Delaware for over 20 years. He has published over 115 papers, has 4 patents and recently edited the book “Multidimensional Liquid Chromatography.” His scientific interests include the fundamental separation science of complex molecules, polymers and colloids, colloid chemistry and materials science and all aspects of solving large-scale chemical and physical problems with computers. His contributions to separation science include detailed theory, simulations and experimental investigations in the areas of 2D chromatography, chromatographic stationary phase calculations and mechanism, capillary electrophoresis, electrochromatography and field-flow fractionation. He has received many awards including the Arthur Doolittle award from the American Chemical Society, the Northeastern University Distinguished Alumni Lecture award, the Douglas Leng award from The Dow Chemical Company, the Eastern Analytical Symposium award in separation science and the L. S. Palmer award from the Minnesota Chromatography Forum. In 2015 he received the Stephen Dal Nogare award and the Uwe D. Neue award.