Applications of immobilised artificial membrane chromatography to quaternary alkylammonium sulfobetaines and comparison of chromatographic methods for estimating the octanol–water partition coefficient

The chromatographic behaviour of a series of quaternary alkylammonium sulfobetaines of general formula RN+(CH3)2(CH2)nSO3−, where n=2–4, has been examined using an immobilised artificial membrane column. The k values have been correlated both with experimentally determined values for the octanol–water partition coefficient (P) and with aquatic toxicity measurements. Other indirect chromatographic methods for measuring log P for these compounds using reversed-phase columns and octanol-coated columns have also been investigated.