Description
In a theoretical study [1], Adler et al. considered the idea of packing columns with so-called ‘spiky particles’. These particles display radially oriented, elongated protrusions or spikes, evenly spaced on the particles spherical surface. It now turns out that, just like the regular particles used in chromatographic beds, these particles can be made out of porous silica , with a spherical shape and a size of a few micrometers [2]. The production process can be tuned to change the width and length of the spikes, as well as the amount of spikes per particle. It is obvious that, if these particles were to be used as a chromatographic support structure, the morphology of the bed would be influenced by new parameters such as spike width, length and amount of spikes per particle. Up till now, it is unclear whether such new bed morphologies could offer some benefit in terms of separation performance and, if so what the exact origin of this improved performance would be and if an optimal spiky particle shape exists.The present work aims to answer these questions and reports on a computational fluid dynamics study (CFD) on mobile phase flow and analyte transport in spiky particle beds. For several bed morphologies, covering a wide range of external porosities, the velocity field was simulated. This allows to determine the permeability of these beds. Subsequently the chromatography version of the Brenner method was used to simulate the transport of analyte, subjected to these velocity fields, yielding the plate height as function of the mobile phase velocity.
It was shown that beds of spiked particles and beds of regular, spherical particles lead to similar degrees of band broadening. However, the main advantage of spiky particle beds is that they can attain a higher external porosity than regular beds. This results in lower permeability, reducing the required pressure to perform a separation within a certain time. By combining band broadening and permeability in kinetic plots, it was shown that spiky particles have the potential to outperform regular particles for complex separations where plate counts N > 50000 are required. In case typical particle dimensions continue to decrease, the region in which spiky particles are beneficial would shift to lower plate counts.
[1] Malinouskaya, I., Mourzenko, V., Thovert, J-F., Adler, P.M., Phys. Rev. E, 80 (2009) 011304. Page HPLC 2025 Bruges Abstract Book 95 Oral Presentations
[2] Dong, H., Lopez, D.A., WO 2021/188945 A1, 23.09.2021.
| Period | 18 Jun 2025 |
|---|---|
| Event title | HPLC 2025 - 54th International Symposium on High Performance Liquid Phase Separations and Related Techniques |
| Event type | Conference |
| Degree of Recognition | International |