Disulfiram metabolite S-methyl-N,N-diethylthiocarbamate quantitation in human plasma with reverse phase ultra performance liquid chromatography and mass spectrometry

• Published in: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Vol. 897; pp. 80 - 84
• Main Authors: Hochreiter, Jill, McCance-Katz, Elinore F., Lapham, Jill, Ma, Qing, Morse, Gene D.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15-05-2012
• Subjects: alcohol abuse; Assaying; Chromatography, High Pressure Liquid - methods; Chromatography, Reverse-Phase - methods; cocaine; cytochrome P-450; Disulfiram; Disulfiram - blood; Disulfiram - metabolism; Disulfiram - pharmacokinetics; Drug Stability; Drugs; HIV infections; Human; Human immunodeficiency virus 1; Humans; Liquid chromatography; Mass spectrometry; Mass Spectrometry - methods; Metabolites; monitoring; oxidation; pharmacokinetics; proteinase inhibitors; Receiving; Reproducibility of Results; Run time (computers); S-Methyl-N,N-diethylthiocarbamate; spectrometers; Thiocarbamates - blood; Thiocarbamates - metabolism; Thiocarbamates - pharmacokinetics; Ultra performance liquid chromatography; Ultra performance liquid chromatography; Disulfiram; S-Methyl-N,N-diethylthiocarbamate; Mass spectrometry
• ISSN: 1570-0232; 1873-376X
• DOI: 10.1016/j.jchromb.2012.03.035

► Disulfiram is rapidly metabolized to active metabolites via CYP450 oxidation. ► Metabolites of disulfiram have different therapeutic applications in humans. ► Interaction studies have been done with disulfiram and HIV medication. ► Measurement of the disulfiram metabolite, S-methyl-N,N-diethylthiocarbamate was needed. ► A UPLC–MS method for this metabolite was developed and validated.
Disulfiram has been used extensively for alcohol abuse and may have a role in treatment for cocaine addiction. Recent data suggest that disulfiram may also reactivate latent HIV in reservoirs. Disulfiram has complex pharmacokinetics with rapid metabolism to active metabolites, including S-methyl-N,N-diethylthiocarbamate (DET-Me) which is formed from cytochrome P450 (CYP450). Assessing disulfiram in HIV-infected individuals with a CYP450 inducing drug (e.g., efavirenz) or a CYP450 inhibiting drug (e.g., HIV-1 protease inhibitors) requires an assay that can measure a metabolite that is formed directly via CYP450 oxidation. Therefore, an assay to measure concentrations of DET-Me in human plasma was validated. DET-Me and the internal standard, S-ethyldipropylthiocarbamate (EPTC) were separated by isocratic ultra performance liquid chromatography using a Waters Acquity HSS T3 column (2.1mm×100mm, 1.8μm) and detection via electrospray coupled to a triple quadrupole mass spectrometer. Multiple reaction monitoring in positive mode was used with DET-Me at 148/100 and the internal standard at 190/128 with a linear range of 0.500–50.0ng/mL with a 5min run time. Human plasma (500μL) was extracted using a solid phase procedure. The interassay variation ranged from 1.86 to 7.74% while the intra assay variation ranged from 3.38 to 5.94% over three days. Representative results are provided from samples collected from subjects receiving daily doses of disulfiram 62.5mg or 250mg.