Jönsson B A, Akesson B
Department of Occupational and Environmental Medicine, University Hospital, Lund, Sweden.
J Chromatogr B Biomed Sci Appl. 1997 Jul 4;694(2):351-7. doi: 10.1016/s0378-4347(97)00125-4.
A method for simultaneous determination of 5-hydroxy-N-methylpyrrolidone and 2-hydroxy-N-methylsuccinimide in urine is described. These compounds are metabolites of N-methyl-2-pyrrolidone, a powerful and widely used organic solvent. 5-Hydroxy-N-methylpyrrolidone and 2-hydroxy-N-methylsuccinimide were purified from urine by adsorption to a C8 solid-phase extraction column and then elution by ethyl acetate-methanol (80:20). After evaporation, the samples were derivatised at 100 degrees C for 1 h by bis(trimethylsilyl)trifluoroacetamide. Ethyl acetate was then added and the samples were analysed by gas chromatography-mass spectrometry in the electron impact mode. The extraction recovery for 5-hydroxy-N-methylpyrrolidone was about 80% while that for 2-hydroxy-N-methylsuccinimide was about 30%. The intra-day precision for 5-hydroxy-N-methylpyrrolidone was 2-4% and the between-day precision 4-21% (4 and 60 microg/ml). The intra-day precision for 2-hydroxy-N-methylsuccinimide was 4-8% and the between-day precision 6-7% (2 and 20 microg/ml). The detection limit was 0.2 microg/ml urine for both compounds. The method is applicable for analysis of urine samples from workers exposed to N-methyl-2-pyrrolidone.
