Determination of 5-methoxypsoralen in human serum

A high performance liquid chromatography with fluorometric and ultraviolet detection described to quantify 5-methoxypsoralen (5-MOP) percutaneous absorption in humans after the application of an essential oil, as well as 5-MOP in bergamot oil and cosmetics by fluorometric and voltammetric measurement, respectively. A muBondapack C(18) analytical column (particle size 5 microm, 3.9 x 300 mm) eluted with acetonitrile-tetrahydrofuran-water (70:15:15, v/v/v) containing 0.07% trifluoroacetic acid. The quantification limits are 0.05 and 0.26 ng for 5-MOP and 5-geranoxypsoralen, respectively. For fluorometric measurement was found linear over the range 0.05-3.00 microg/ml for psoralens. Five volunteers blood samples were collected over a 2-day period were investigated before and after treatment with bergamot oil. Serum levels of 5-MOP were significantly increased from the 4 h after the application of bergamot essential oil. The hourly mean levels were significantly higher after the application of bergamot essential oil compared to baseline values.