I have two theorical questions about HPLC:

1.- In some conversation I have seen how people talks about % Carbon in the HPLC columns. Which is the importance of this parameter in the HPLC ?. Is there any specific rule ?

2.- If I have to use an amine to improve the HPLC system which of the amine is better (triethylamine, diethylamine, octylamine, N,N-Dimethylocthylaminen, any other?. Is there any rule how to chose ?

Thanks

1. By itself, % Carbon gives little information. If you compare columns of the same specific surface (square meters of surface per gram of packing) and with the same type of bonded phase (e.g., C18), then higher %carbon generally means more complete derivatization.

2. Other things being equal, the more hydrophobic and/or basic the tailing suppression reagent, the more effective it is at suppressing tailing, and the slower it is to equilibrate. My personal preference is for rapid equilibration, so I will tend to use triethylamine most of the time.

-- Tom Jupille / LC Resources