DETECTION AND QUANTIFICATION OF METHADONE AND ITS METABOLITE 2-ETHYLIDENE-1,5-DIMETHYL-3,3-DIPHENYLPYRROLIDINE (EDDP) IN URINE PAIN MANAGEMENT COMPLIANCE TESTING BY HIGH-PRESSURE LIQUID CHROMATOGRAPHY WITH TANDEM MASS SPECTROMETRY

Abstract

Presently urine analysis for methadone and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) is performed for emergency toxicology screening and pain management compliance testing (PMCT). Presented is the validation of a high-pressure liquid chromatography with tandem mass spectrometry method for methadone and EDDP in urine. Samples were simply diluted 1:1 (v:v) with 0.1 µg/mL of methadone-d₃ and EDDP-d₃ in methanol before analysis. The chromatographic separation was performed using a Pinnacle C18 100 × 3.2 mm, 3 µm column with a mobile phase containing water/acetonitrile (20:80 v:v) with 1% formic acid delivered at a flow rate of 0.5 mL/min.

Detection was accomplished by multiple-reaction monitoring via electrospray ionization source operating in the positive ionization mode. The calibration curve was linear over the investigated concentration range, 25 to 5000 ng/mL, for both methadone and EDDP. The lower limit of quantitation for each analyte was 25 ng/mL. The intra- and inter-day precisions had coefficient of variations less than 15% and the accuracy was within the range from 94% to 110%. The method proved adequate for methadone and EDDP analysis of urine for emergency clinical toxicology and PMCT.

Keywords:

• EDDP
• HPLC/MS/MS
• methadone
• pain management compliance testing
• synthetic opiates
• urine drug testing

ACKNOWLEDGMENT

This study was supported by the National Institute of Drug Abuse (NIDA) Center for Drug Abuse grant P50DA005274.

Notes

Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/ljlc.