
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.
| Mobile Phase | MeCN |
|---|---|
| Buffer | TFA |
| Flow Rate | 1.0 ml/min |
| Detection | UV, 250 nm |
| Class of Compounds | Drug, Acid, Hydrophilic, Ionizable, Vitamin, Supplements |
| Analyzing Compounds | 3.4-dihydroxybenzoic acid, 3.5-dihydroxybenzoic acid,2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid |