Chromatography Forum

I've gotten my hands on an EP method that we need to use to test a raw material. The EP states that a end-capped polar-embedded octadecylsilyl amorphous organosilica polymer R (5 um) is to be used for the method.

I'm thinking that this means I could use an XTerra RP-18 as it is the only column I am aware of that is a hybrid (I take it that is what the EP means by organosilica polymer, but have no idea if it is type R) which also contains a polar embedded group.

Have I hit the jackpot, or do I need to go back to fishing; have I misunderstood something? I don't deal with the EP all that often....

The EP has their Knowledge basew which will tell you what column is used, and may even provide a chromatogram. Just go fishing there, very likely to catch something tasty...

http://extranet.pheur.org/publications/ ... s_sw.shtml

Please keep having fun,

Bruce Hamilton

There are only two packings which fit the description of a reversed-phase packing with an embedded polar group based on an organosilicon polymer. One is XTerra RP18, the other one is XBridge Shield RP18. Considering that EP methods are often older methods, I agree with you that the correct choice is most likely XTerra RP18.