Determination of Caffeine in Cosmetics by High Performance Liquid Chromatography-Ultraviolet Detection
A method was developed for the determination of caffeine in cosmetics products by high performance liquid chromatography(HPLC).Samples were extracted with methanol and then diluted well or dissolved in hexane and then reverse extracted by methanol and water.The samples were separated on a Waters Atlantis T3(4.6 mm×150 mm,5 μm)HPLC column with the mobile phases of methanol and water.The flow rate was 1.0 mL/min under gradient elution,the detection wavelength was 273 nm and the column temperate was 40℃.The results show that the calibration curves had good linearity in the range of 0.2 mg/kg to 10 mg/kg,with correlation coefficients greater than 0.9999.The average recoveries at the three spiked levels of seven matrixes were in the range of 105.5%to 110%and the relative standard deviations(RSDs)are in the range of 0.7%to 4.5%.The limit of quantification was 10 mg/kg.With the advantages of convenience,sensitivity,good recoveries,efficient and accurate,the established method can be used for the detection of caffeine in cosmetics products.
high performance liquid chromatographyultraviolet detectioncaffeinecosmeticsmethodology