HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF 4-METHYLPYRAZOLE IN PLASMA AND IN DIALYSATE

A rapid method for the determination of 4-methylpyrazole (4-MP) levels in plasma and in dialysate by isocratic reversed-phase high-performan ce liquid chromatography with UV detection is described. The internal standard was the 3-methylpyrazole (3-MP). Plasma sample preparation co nsisted of a protein precipitation, Dialysate samples were injected wi thout preparation. The method was linear up to 30 mg l(-1) in plasma a nd up to 5 mg l(-1) in dialysate. The within-day precisions (C.V.) wer e less than 4% in plasma and were less than 2% in dialysate. The day-t o-day precisions (C.V.) were less than 7% in plasma and were less than 3% in dialysate. This method is easy to perform and has practical int erest for clinicians who need to monitor in emergency 4-MP levels in e thylene glycol and methanol poisonings. (C) 1997 Elsevier Science B.V.