Features of Multimode Columns (Nucleic Acid Analysis)

Asahipak GS-320 HQ is a column which operates basically in SEC mode. However, depending on the eluent conditions, it allows separation by multiple modes combining reversed phase and ion exchange modes. The column is particularly effective in analyzing samples such as proteins and nucleic acid components, which are made up of both acidic and basic components. In this separation mode, samples are eluted in the order of acidic, neutral and basic. Separation can also be adjusted by changing the eluent components.

1) When a neutral/acidic eluent is used.

Acidic samples	As it is the ion exclusion mode which is in operation, substances are eluted relatively quickly.
Neutral samples	As substances are separated by reversed phase mode, they are eluted moderately.
Basic samples	As it is the ion exchange mode which is in operation, substances are eluted relatively slow.

2) When a basic eluent is used.

Acidic samples	Basically, substances are excluded together at the Vo position but, with acidic samples of large molecular weights, there are cases in which substances are retained in the column.
Neutral samples	Substances are separated by reversed phase mode.
Basic samples	If the eluent has a higher pH than the pKa of the sample, substances are separated by reversed phase mode as the dissociation of basic samples is suppressed.