Dear members,
I received two opposite ideas for surfactant separation.
One said detergents should not be injected on column because some classes would bind to reverse phase column. Elution will be hard.
And another, most agreed with, said retention of this kind sample is very weak for easy ionization. The first focus in this run is to strengthen the retention.
Which idea is accurate?
Thank you.
Michelle

Surfactants ..... What kind of surfactants?

Ionic or non ionic...??

First, surfactants are generally well retained via reversed phase regardless of the eluent system. Second, the magnitude of the retention depends on whether you're referring to anionic, cationic or nonionic surfactants as well as whether or not the surfactants are aromatic or aliphatic. Third, retention of ionic surfactants is generally also affected by the presence of other electrolytes with increases in ionic strength resulting in increased retention. Fourth, the nature of the counterion supplied in the mobile phase (i.e. the cationic eluent component in the case of anionic surfactants and the anionic eluent component in the case of cationic surfactants) also affects the retention of ionic surfactants. The less hydrated the counterion, the more retention you will observe. For example, you will see less retention for dodecylsulfate with a lithium containing eluent system than with a potassium containing eluent system. Finally, cationic surfactants have a tendency to strongly associate with silanols in reversed phase media. Generally it's best to use low pH separation conditions to minimize this problem or to add a competing cation such as TEA to the eluent system to minimize this problem.