Quantitative LC-MS/MS Analysis of Opiates and Opioids in Human Urine.

We hereby present a direct, clinical LC-MS/MS assay for the simultaneous analysis of opiates and opioids in human urine. The assay is used as confirmations as well as a quantitative assay following immunoassay urine drug screens. Hence, the utility is extended to report opiate/opioid levels in the range 10-1000 ng/mL for each of the 13 analytes, which include morphine and metabolites; codeine and metabolites; as well as synthetics such as heroin metabolites, dihydrocodeine, oxycodone, and naloxone. The assay employs dilute and shoot, utilizing reversed-phase liquid chromatography for mixture separation and positive-mode electrospray-ionization multiple-reaction-monitoring for MS detection in the TSQ Endura triple-quadrupole (QqQ) instrument. Thereafter, quantitative analysis is based on the linear calibration using six reference standards, whereby the instrument response for each analyte at a given concentration is normalized against stable isotope labeled internal standard.