The Chromatography Forum

of Delaware Valley

For Reservations: Please register below by clicking "Register Now" where you can pay by PayPal. You can also register by e-mailing Sheree Gold at sheree@cfdv.org indicating you name, employer and work telephone. Alternatively, you can telephone Ms. Gold at 610-742-4981 and provide this same information. Please note that “no shows” will be billed for the dinner.

Inclement Weather Cancellation Policy: Cancellations will be accepted up until 12:00 pm (noon)  on the day of the meeting (February 20th).

Generic Cancellation Policy: Cancellations will be accepted up until 4pm on February 19th.

Abstract: Large pore volume is thermodynamically advantageous in Size Exclusion Chromatography (SEC) and is thought to be a necessity for high resolution separations by molecular size. In a recent study1 superficially porous particles (SPPs) were found to have kinetic advantages over fully porous particles (FPPs) for use in SEC. In this talk, a comparison is made using FPPs and SPPs with similar particle diameter, pore size and equal flow rate using polystyrene solutes. A complete set of characterization metrics show that SPPs offer similar peak capacities to FPPs but with faster operation because SPPs produce more plates and more plates per unit time than FPPs1. Optimization of the shell thickness is discussed using the general rate model of chromatography. There is no optimal shell thickness; one can optimize for peak capacity or for plates but not both. However, there is a “sweet spot” where one can reach a reasonable compromise in raising performance beyond FPPs. Applications of this technology include many separations of biomolecular interest. In this talk fast gold nanoparticle characterization for particles with various surface chemistries will be discussed. Comparison will be given to nanoparticle separations in the literature and the advantage of SPPs will be shown. Large pore SPPs have been modeled with very high-resolution fluid mechanics allowing the pore flow velocity field to be determined2. This shows a small flow through the shell thickness and can increase the performance for larger molecular weight solutes separated by SEC. The corresponding shear field allows one to evaluate possible chemical bond scission based on shear for large molecules. This is a longstanding issue in SEC. The regions near the hull show possible shear effects but there are other sources, including adsorption itself, which can drive bond scission. Using SPPs for SEC in 2DLC, in either first or second dimension has advantages and disadvantages and these will be discussed. Since speed in the second dimension is desirable for high-resolution sampling, SPPs can be used to advantage for second dimension SEC.

1 M. R. Schure, R. E. Moran, Size exclusion chromatography with superficially porous particles, Journal of Chromatography A 480 (2017) 11-19.

2 M. R. Schure, R. S. Maier, T. J. Shields, C. M. Wunder, B. M. Wagner, Intraparticle and interstitial flow in wide-pore superficially porous and fully porous particles, Chemical Engineering Science, 174 (2017) 445– 458.

Click here for PDF Version