|Molecular Weight||154.121 g/mol|
Primesep B offers better selectivity over traditional, reversed-phase C18 columns for separating regioisomers of aromatic dihydroxybenzoic acids (2,3-dihydroxybenzoic, 2,4-dihydroxybenzoic, 2,5-dihydroxybenzoic 3,4-dihydroxybenzoic, 3,5-dihydroxybenzoic acids) Primesep B combines reversed-phase and anion-exchange mechanism with a mass spec compatible mobile phase of water, acetonitrile (MeCN, ACN) and trifluoracetic acid (TFA).
Separation of hydrophilic isomers is very difficult when only one mechanism of retention, like reversed-phase, is available. Isomers have very similar hydrophobic properties. In case of mixed-mode chromatography, small difference in hydrophobic and ionic properties allows to separate isomers. Isomers of dihydroxybenzoic acids are separated on a Primesep D column with good selectivity and peak shape. This method can be used for separation of other hydrophilic acidic compounds as well as hydrophobic basic compound.