Analytical Considerations When Monitoring Pain Medications by LC-MS/MSAmadeo Pesce1*, Cameron West1, Robert West1, Sergey Latyshev1, David Masters-Moore1, Patrick Friel2, John M. Hughes2, Perla Almazan1, Elizabeth Gonzales1 and Charles Mikel1
- *Corresponding Author:
- Amadeo Pesce
Millennium Research Institute, San Diego, CA, USA
Received date: May 17, 2012; Accepted date: June 23, 2012; Published date: June 28, 2012
Citation: Pesce A, West C, West R, Latyshev S, Masters-Moore D, et al. (2012) Analytical Considerations When Monitoring Pain Medications by LC-MS/MS. J Anal Bioanal Techniques S5:003. doi: 10.4172/2155-9872.S5-003
Copyright: © 2012 Pesce A, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Background: Laboratory urine drug testing of patients on chronic opioid therapy requires providing a large test menu of medications commonly prescribed for this population as well as metabolites and illicit substances. It has been shown that liquid chromatography-tandem mass spectrometry (LC-MS/MS) is the preferred method to analyze urine specimens for these substances.
Purpose of the study: To describe the challenges and some of the techniques to validate the analytical procedures used to identify and quantify these medications and substances.
Methods: Using data obtained from testing over one million specimens, the authors developed a proposed test menu. Potential isobaric interferences were established by using literature references. A list of potentially interfering medications was obtained by using the proposed test menu and the most commonly prescribed medications. Finally, criteria were designed to detect possible carryover.
Results: The LC-MS/MS instrumentation eliminated all potential interferences and provided quantitative data over the test range needed to monitor these patients. Carryover could be eliminated by setting the carryover thresholds for each analyte.
Conclusions: Reference laboratories utilizing LC-MS/MS technology to conduct urine drug testing for pain clinicians should employ specific techniques described in this study to develop an optimal test menu and validate procedures that include isolating retention times for isobaric compounds, identifying interfering substances including impurities in medicinal and illicit substance preparations, monitoring ion suppression, and avoiding carryover.