Simultaneous determination of the nine food additives using high-performance liquid chromatography

A technique for the simultaneous determination of sorbic acid, benzoic acid, dehydroacetic acid, p-hydroxybenzoic acid esters (ethyl, isopropyl, n-propyl, isobutyl and n-butyl p-hydroxybenzoate) and saccharin sodium using ion-pair reversed-phase high-performance liquid chromatography is described. The nine food additives were separated on a Nucleosil 3C18 (3 microns) column (75 x 4.6 mm I.D.) using methanol-acetonitrile-0.05 M aqueous acetonic acid solution (pH 4.5) (1.5:1:3.1) containing 2.5 mM cetyltrimethylammonium chloride as the mobile phase at a flow-rate of 1.0 ml/min, and detected at 233 nm. The food additives were separated within 18 min and their calibration graphs were linear between 2 and 200 ng.