Determination of methyleugenol in rodent plasma by high-performance liquid chromatography.

A method has been developed and validated for the analysis of methyleugenol, a volatile flavoring agent, in rodent plasma at concentrations from 0.050 to 10.0 micrograms/ml. The method involves the addition of acetonitrile to the plasma, removal of the protein precipitate, and analysis of the supernatant by reversed-phase (C18) HPLC using an acetonitrile-water mixture with UV detection. The precision, accuracy, sensitivity, and specificity of the method were assessed. The stability of methyleugenol in plasma, during freeze-thaw cycles, refrigerated at the extract stage, and during the analysis was evaluated. The recovery of methyleugenol from plasma was also determined. This method was found to be acceptable for plasma concentrations in toxicokinetic studies of methyleugenol in rodents. Over 400 samples from toxicokinetic studies have been successfully analyzed to date. Kinetic data from a preliminary single administration intravenous and oral study in rats is also presented.