Objective: A high performance liquid chromatographic (HPLC) method was developed for the simultaneous determination of 4 furocoumarins, including 8-methoxycoumarin, 5-methoxycoumarin, trioxsalen and imperatorin in cosmetics.
Methods: The separation was carried on Diamonsil C18 column (4.6 mm x 250 mm, 5 microm) by gradient elution with methanol-water as mobile phase at a flow rate of 1.0 ml/min and column temperature of 30 degrees C. The analysis of 4 furocoumarins was performed by HPLC with diodearray detector at the wavelength of 248 nm.
Results: Identification of 4 furocoumarins was achieved by retention time, and quantification analysis was performed by the external standard method. The limits of quantitation (LOQ) for 4 furocoumarins were 0.54, 0.52, 0.58 and 0.50 microg/g, respectively. The method showed a good linearity in the range of 0.05-10 microg/ml with correlation coefficients more than 0.999. The mean recoveries at spiked levels were in the range of 89.9%-105.2% with RSDs of 0.20%-1.08%.
Conclusion: The method was accurate and simple, and was suitable for the determination of 4 furocoumarins in cosmetics.