Does anyone know a supplier(s) of 4.6 mm ID columns with a phenyl-cyano packing? (25 cm preferred, but we could start with 15 cm.) We are trying to improve a normal-phase separation currently being run on a CN column. The mobile phase, flow rate, etc. appear to be optimized for the HP Lichrospher CN, and it also works OK, though not quite as well, on CN columns from a couple of other vendors.

Try Phenomenex's LunaŽ line--I think they make a phenyl-cyano, but I've heaerd it's not too stable and lot-to-lot variability is high.

I am not aware of a phenyl-cyano column, and I would not expect any such phase to be very rugged.

A correction on the comment about the LUNA column. This column is not a phenyl-cyano, but a Phenyl-Hexyl (uses a hexyl alkyl linker rather than the typical 3 carbon propyl to attach the phenyl group to the base silica). The phase is as stable as a C18 and very reproducible. Data can be supplied if interested.

A LUNA CN is available with uses the LUNA base silica. The silica is extremely advanced and seems to have solved many of the problems associated with CN phases. It has proved to be a very good improvement over many existing CN columns. If you are interested, feel free to contact Phenomenex @ (310)212-0555, Emmet Welch.

does any one know the chemistry of utremex cyno column

You should ask the supplier. High-quality suppliers give you this information, often with the Certificate of Analysis that comes with the column.