Determination of sevoflurane and its metabolite hexafluoroisopropanol by direct injection of human plasma into gas chromatography–tandem mass spectrometry

The developed method for trace analysis of volatile components in plasma allows direct injection of up to 150 samples to the GC–MS/MS system without injector cleaning. This method requires no modification of plasma and the working environment does not interfere with the determination of these analytes. The method allows simultaneous quantification of non-polar sevoflurane and its polar metabolite hexafluoroisopropanol (free, unconjugated form). It is characterized by high repeatability and sensitivity with the detection limit of 0.009 mg L−1 for sevoflurane and 0.018 mg L−1 for hexafluoroisopropanol and the linear range 0.050–150 mg L−1. The method was used to determine the concentration of sevoflurane and hexafluoroisopropanol in plasma samples of 7 patients undergoing general anesthesia with sevoflurane. The average concentration of sevoflurane and free hexafluoroisopropanol was 57.2 mg L−1 and 0.39 mg L−1, respectively. The method can be applied for clinical monitoring, as well as for analytical toxicology.

► A new method for the determination of the anesthetic agent sevoflurane and its metabolite hexafluoroisopropanol was developed.
► The method is based on the direct injection of human plasma into a GC–MS/MS system without any sample preparation.
► The LOD and LOQ for sevoflurane are 0.009 and 0.017 mg L−1 and for hexafluoroisopropanol 0.018 and 0.032 mg L−1, respectively.
► The developed method was applied in the analysis of plasma samples of patients after anesthesia.