Submicrogram assay for scopolamine in plasma and urine.

A GLC-mass spectrometric method for scopolamine, sensitive to 50 pg/ml for a 4-ml plasma or urine sample, was developed. The method used a deuterated internal standard to minimize variability in absolute recovery in the extraction procedure. Scopoline and deuterated scopoline were formed from the base-catalyzed hydrolysis of scopolamine and the internal standard and were analyzed as the heptafluorobutyrates, using a GLC-mass spectrometric system by monitoring the m/e 138 and 141 fragments, respectively.