Carlos,
It depends a lot on specifically what you're interested in what the best choice is but one column you should certainly take a look at is the surfactant analysis column from Dionex (
http://www1.dionex.com/en-us/columns_ac ... p5669.html ). You can find more information about it including specific chromatographic conditions for sodium dodecyl benzene sulfonate at this link. There are actually two types of surfactants with the same basic nomenclature. The most commonly used version is the biodegradable surfactant often referred to as LAS but also sometimes referred to as dodecylbenzene sulfonate. There is also a nonbiodegradable version with a straight chain hydrophobe. If you are interested in the maximum possible resolution of the various different hydrophobic components (surfactants of this type are almost always mixtures was arraigned a different hydrophobic side chains), a standard C18 column might work better. With the column detailed at the link above, the separation is based more on carbon number than branching structure so the chromatographic profile of such compounds is simplified. Perhaps you could supply some additional details about what you're specifically interested in with regard to this analyte.
