Ion-pair high-performance liquid chromatography: the use of low concentrations of long-chain...

The qualitative and quantitative determination of large anionic solutes, including the drug sodium cromoglycate, by an ion-pair high-performance liquid chromatographic technique using alkylbenzyldimethylammonium chlorides as pairing ions is described. The method provides a sensitive and selective assay for the solutes examined in both simple aqueous solutions and in complex biological fluids, and requires no pre-extraction step. Retention mechanisms are discussed.