Abstract:

A method for the simultaneous determination of seven sulfonamides (sulfacetamide, sulfapyridine, sulfamerazine, sulfamethazine, sulfamater, sulfamonomethoxine, sulfamethoxazole)and metronidazole, chloramphenicol in cosmetics has been developed by high performance liquid chromatography with a photodiode array detector(HPLC-PDA). The chromatographic column Atlantis dC18 (150 mm×4.6 mm, 5 μm) was used with acetonitrile-0.1% formic acid (2∶8, v/v) aqueous solution as mobile phase at a flow rate of 1.0 mL/min. Samples were extracted by mobile phase and detected by HPLC-PDA at 268 nm. The limits of quantification were 3-80 μg/g. The correlation coefficients of linear calibration curves were over 0.9993 within the sulfonamide concentration range of 20-200 μg/mL and metronidazole and chloramphenicol concentration range of 40-400 μg/mL. Average recoveries were 83.8%-105.3% at the spiked levels of 50 μg/mL and 150 μg/mL for sulfonamides, and 100 μg/mL and 300 μg/mL for metronidazole and chloramphenicol. The relative standard deviations were below 5%. This method can be routinely used for the determination of seven sulfonamides and metronidazole, chloramphenicol in cosmetics.

Key words: chloramphenicol, cosmetics , metronidazole, sulfonamides, high performance liquid chromatography (HPLC)