ABSTRACT
Vortex-assisted liquid–liquid microextraction is reported for the preconcentration of chloramine-T before determination by high-performance liquid chromatography with a diode array detector. Magnetite nanoparticles were used to remove hydrophobic additives in cosmetics by physical adsorption. The method used sonication for 30 min at 45°C in 40% hydrochloric acid to convert the analyte to p-toluenesulfonamide. 1-Hexanol was the extraction solvent with vortex mixing. The extraction conditions were optimized to provide a linear dynamic range from 0.5 to 500.0µg/mL. The recovery of chloramine-T was from 90.8 to 100.9% with a relative standard deviation from 3.7 to 6.5%. The limit of detection was 8.2 mg/kg and the enrichment factor (EF) was 100. Good repeatability, quantitative recovery, and a high EF demonstrated the suitability of the procedure for the determination of chloramine-T in cosmetics.