Sensitive determination of pethidine in body fluids by gas chromatography–tandem mass spectrometry

We have presented a simple and sensitive method for determining pethidine, a narcotic analgesic drug in body fluids by gas chromatography–tandem mass spectrometry (GC–MS/MS). Pethidine and 4′-piperidinoacetophenone (internal standard) were extracted from body fluids with Bond Elut C18 columns; the recoveries were above 85% for both compounds. The calibration curves for blood and urine showed good linearities in the range of 1.25–40 ng/ml. Its detection limits (signal-to-noise ratio=3) were estimated to be approximately 0.5 ng/ml of whole blood and urine.