Simple and rapid determination of psoralens in topic solutions using liquid chromatography

A method for sample preparation and high-performance liquid chromatography detection and quantification has been developed for the routine analysis of psoralen and bergapten, photosensitizing compounds, in topic solutions employed in Brazil for treatment of vitiligo and psoriasis. The linearity, accuracy, the inter- and intra-day precision of the procedure were evaluated. The calibration curve for psoralen and bergapten were linear in the range 1.0-20.0 microg ml(-1). The best recoveries of the psoralens in the topic solutions analysed were 96.3-98.2%. The percentage coefficient of variation of the quantitative analysis of the psoralens in the product analyses was within 5%.