Determination of seven restricted halogenated salicylanilides in cosmetics by high performance liquid chromatography

Abstract

A simultaneous analytical method was established for the determination of seven halogenated salicylanilides, namely 5-bromo-4′-chlorosalicylanilide, dibromsalan, tribromsalan, metabromsalon, 3,3′,4′,5-tetrachlorosalicylanilide, 4′-bromosalicylanilide, and 5-chlorosalicylanilide, in cosmetics by a high performance liquid chromatography-fluorescence detector (HPLC-FLD) in this work. The seven analytes were extracted by acetonitrile and separated on a T3 column by a gradient elution program, with the mobile phase consisting of 0.1% formic water (50% at the beginning) and acetonitrile. The mobile phase, chromatographic column types, wavelength, and column temperature were optimized. The calibration curves were linear in the ranges of 100–5000 μg kg⁻¹ for tribromsalan, metabromsalon, and 3,3′,4′,5-tetrachlorosalicylanilide and 200–5000 μg kg⁻¹ for the remaining four analytes, with correlation coefficients greater than 0.9996. The limits of detection (LODs) and the limits of qualification (LOQs) of the method were 13.8–42.9 μg kg⁻¹ and 46.0–143 μg kg⁻¹, respectively. Recoveries of the seven analytes ranged from 70% to 110%, with relative standard deviations (RSDs) of less than 13%. This method exhibits uncomplicated operation, excellent linearity, high sensitivity, and superior reproducibility for the determination of halogenated salicylanilide residues in cosmetics.