Rapid and sensitive determination of acetylsalicylic acid and its metabolites using reversed-phase high-performance liquid chromatography.

A rapid and sensitive high-performance liquid chromatographic technique was developed for the simultaneous determination of gentisic acid, salicyluric acid, acetylsalicylic acid and salicylic acid in plasma and serum. The method involved a single deproteinization step and separation using a reversed-phase column eluted with a buffered methanol (35%) mobile phase. Detection was achieved with a variable-wavelength ultraviolet detector set at 235 nm and a given chromatographic analysis could be completed in less than 10 min. The method was tested in both human and animal (rat) models given a single dose of acetylsalicylic acid.