Good to hear from you again! Since I have two samples, I will try repeating the Kaburagi-Kishi method on one and using reverse phase methodology on the other. On my shelf I have an old, probably unused 20-gram sample from JT Baker, of Bonded phase-octadecyl (C18), having an average particle diameter of 40-µm and described as being for flash chromatography. I also have a product from Analtech (catalog #50010) that is RPS hydrocarbon impregnated silica gel, 35-75 micron. I found a description at Amazon. If I am reading this correctly, the hydrocarbon impregnated product is not covalently linked to the silica and would come off in a sufficiently non polar solvent (if one is not careful).
"Silica gel and bonded phases are based upon a 150A pore silica gel, 35-75um particle. SPICE Packings are available in bulk quantities of 100 grams, 500 grams, 5 kg, and 10 kg. For larger quantities call for a price quote. Analtech offers two types of reversed phase packings for column chromatography: A C18 octadecyl bonded silica gel and a hydrocarbon impregnated silica gel. The most common reversed phase adsorbent is the octadecyl (C18) bonded silica gel. The C18 hydrocarbon is chemically anchored to the silica gel support. This material is compatible with all aqueous and organic solvent combinations. The carbon content is about 14%. Pore size is 150 Å Particle size is 35-75 microns. The hydrocarbon impregnated silica gel is a column grade equivalent of Analtech's unique RPS UNIPLATE. The long chain hydrocarbon is not chemically bonded to the silican get but is adsorbed onto the surface. This material is compatible with classical reversed phase eluting solvents such as MeOH/Water and Acetonitrile/Water. Less polar organic solvents will solubilize the hydrocarbon. The Reversed Phase Separation (RPS) column material is ideal for prep scale separations established on RPS UNIPLATES. Carbon content is about 5%. Pore size is 60 Å. Particle size is 35-75 microns."
I seem to recall from a previous discussion that packing and running a column of reverse phase material is quite different from running a silica column, perhaps needing more pressure.
Is one of these two products suitable for our application? If not, what should I buy?