c1d6df67_C18s_Are_the_Same_Aren_t_They___2
[0] C (7.0) [2] 
Silanol Ionisation at pH 7.0. At this pH, all residual silanol groups should be fully ionized and the C (7.0) value gives a measure of the total amount of ionized silanol groups available for secondary interaction with analytes. For optimal alternative selectivity, ideally we should have a large C(7.0) – giving large amounts of silanols available for secondary interactions, but a low C (2.8) – low amounts of activated silanols that cause peak tailing.
All HPLC C18s Are the Same Aren’t They?
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