Simultaneous quantitation of morphine, monobutanoylmorphine and dibutanoylmorphine using short capillary column gas chromatography-mass spectrometry

Abstract

An assay procedure for quantitating 3,6-dibutanoylmorphine, a morphine diester, and its metabolites, 6-monobutanoylmorphine and morphine, has been developed. The method involves a one-step extraction from various biological media, gas chromatographic separation using a short methylsilicone capillary column and sensitive and selective quantitation by single ion monitoring mass spectrometry. The use of short capillary column GC-MS allowed the rapid separation of compounds with dissimilar retentions that are biologically interrelated and must therefore be measured intact in small sample volumes. The application of this method to studies on the metabolism of butanoyl esters of morphine in whole brain homogenates is described.