Determination of the UV filters worldwide authorised in sunscreens by high-performance liquid chromatography -: Use of cyclodextrins as mobile phase modifier

Simultaneous determination of organic W filters worldwide authorised in sunscreen formulations was performed by HPLC with UV spectrophotometric detection. The filters determined were: benzophenone-4, benzophenone-3, butyl methoxydibenzoylmethane, octyl dimethyl PABA, octyl methoxycinnamate, homosalate and octyl salicylate. A C-18 stationary phase and an isocratic mobile phase of ethanol-water-acetic acid (70:29.5:0.5) containing 65.4 mM of hydroxypropyl-beta -cyclodextrin, were used with a flow-rate of 0.6 ml/min. UV measurements were carried out at 313 nm. The time required for the analysis was 20 min and the limits of detection were between 1.5 and 2.3 mg/l. The procedure proposed provides a green analytical method with a basic instrumental configuration, it is fast and accurate and does not involve highly toxic organic solvents. (C) 2001 Elsevier Science B.V. Ah rights reserved.