DETERMINATION OF DIPYRONE METABOLITES IN HUMAN PLASMA BY MICELLAR LIQUID-CHROMATOGRAPHY

The three metabolites of dipyrone found in plasma (4-methylaminoantipy rine, 4-aminoantipyrine and 4-formylaminoantipyrine) were separated an d quantified by micellar liquid chromatography. The method used an 0.1 M sodium dodecyl sulphate mobile phase and an octadecyl silica bonded stationary phase. Dipyrone metabolites were measured by UV detection at 262 nm. The proposed method needs only 5 min to separate the three metabolites at a flow rate of 1 ml/min. The limits of detection (LODs) in plasma ranged between 0.1 and 0.2 ng injected. The method was appl ied to the determination of dipyrone metabolites in human plasma sampl es.