Is it practical to do large-scale liquid column chromatography using a reverse phase method? This would be a preparative separation to precede characterization of compounds using HPLC. We will be doing the separation on plant samples extracted with methanol, so it seems that reverse phase would give more effective separation than normal phase. However, we have only been able to find the packing material (C8) in pre-packed, 1g columns (Altech, ~$100) and we would have to order in bulk by the kilogram (costly based on Altech's price/gram!). Is this a valid approach, and if so is the packing material available in bulk (and from whom)?
Patricia Jones
NASA Scholar-University of Central Florida
Kennedy Space Center, FL

YMC Bulk Packings

For preparative or process chromatography, YMC offers a complete line of spherical and irregular particle sizes in a variety of bonded phase chemistries. Spherical YMC*Gel packings provide completely scalable analytical to preparative separations, high efficiency, and excellent particle characteristics. YMC*Gel irregular particle sizes are an economical choice for flash chromatography, batch purification,single-use and crude preparations. YMC Products are now available
through Waters in the Americas.

1-800-252-4752

I understood that you want to do a flash chromatography prior to HPLC. I am using a Biotage flash chromatography system with prepacked cartridges. They have both silica and RP packings. I believe that RP could be regenerated.

I also suggest that using silica TLC plates you check if you can remove a significant part of the impurities using bare silica.

Also, did you consider a two-phase extraction in a separatory funnel?

If you have more questions please contact me directly.

Michael Breslav
mbreslav@prius.jnj.com

Yes, this is very practical and feasible. I recently did exactly this while scaling up the isolation of an "active component" in human blood that we were isolating. I went through the same process as you and found that the best packing to buy was through Waters Corp. It is a preparatice C18 packing, 125A, 55-105 um, which gave me a pretty reasonable column flow, excellent separation (good carbon loading)and was fairly inexpensive. I believe I ended up buying it by the kilogram for about $900. My solvent system was H2O/CH3CN. I did attempt to apply a flash separation technique, but found that gravity was fast enough and gave a far superior separation of unwanted contaiminants. Good luck.