Determination of methylamphetamine and related compounds in human urine by high performance liquid chromatography electrospray mass spectrometry

A study of liquid chromatography/electrospray/mass spectrometry (LC/ES/MS) for the determination of methylamphetamine and related compounds (amphetamine, ephedrine, phenylpropanolamine) in human urine was undertaken. We assessed the effect of collision induced dissociation (CID) spectra generated by varying exit voltage of capillary and skimmer. The responses of ES/MS in different mobile phase and the effects of mobile phase modifier were examined. An isocratic LC method using methanol/water (80/20) and acetic acid (0.001%) as a modifier to separate these compounds was developed. Microporous ultrafiltration technique was employed to pre-treat urine sample prior to LC/ES/MS analysis. Good recoveries for methylamphetamine and amphetamine were determined as well as linearity, detection limit and precision associated with this method were determined. Drug spiked urine samples and urine samples of methylamphetamine addicts were successfully measured by this newly developed method. (C) 1999 Elsevier Science B.V. All rights reserved.