Determination of fentanyl in human plasma and fentanyl and norfentanyl in human urine using LC-MS/MS
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
Authors: Huynh, NH; Tyrefors, N; Ekman, L; Johansson, M
Abstract
Fentanyl, a potent analgesic drug, has traditionally been used intravenously in surgical or diagnostic operations. Formulations with fentanyl in oral transmucosal delivery system and in transdermal depot-patch have also been developed against breakthrough pain in cancer patients. In this report, LC-MS/MS methods to determine fentanyl in human plasma as well as fentanyl and its main metabolite, norfentanyl, in human urine are presented together with validation data. The validation ranges were 0.020-10.0 and 0.100-50.0 ng/ml for fentanyl in plasma and urine, respectively, and 0.102-153 ng/ml for norfentanyl in urine. Liquid-liquid extraction of the compounds fentanyl, norfentanyl and the deuterated internal standards, fentanyl-d(5) and norfentanyl-d(5) from the matrixes was applied and separation was performed on a reversed phase YMC Pro C-18-column followed by MS/MS detection with electrospray in positive mode. The inter-assay precision (CV%) was better than 4.8% for fentanyl in plasma and 6.2% and 4.7% for fentanyl and norfentanyl, respectively, in urine. The ruggedness of the methods, selectivity, recovery, effect of dilution and long-term stability of the analytes in plasma and urine were investigated. Effect of haemolysis and stability of fentanyl in blood samples were also studied. The methods have been applied for the determination of fentanyl in plasma samples and fentanyl/norfentanyl in urine samples taken for pharmacokinetic evaluation after a single intra-venous (i.v.) dose of 75 mu g fentanyl. (c) 2004 Elsevier B.V. All rights reserved.
A comprehensive LC-MS-based quantitative analysis of fentanyl-like drugs in plasma and urine
JOURNAL OF SEPARATION SCIENCE
Authors: Cooreman, Sarah; Deprez, Christa; Martens, Frank; Van Bocxlaer, Jan; Croes, Kathleen
Abstract
Fentanyl, norfentanyl, alfentanil, sufentanil, remifentanil and 3-methylfentanyl are potent, short-acting, synthetic narcotic analgesics that are not revealed in standard opiate immunoassays. In this article, a fully validated analytical method for the determination of these fentanyl-type compounds in plasma and urine is presented, consisting of a liquid-liquid extraction followed by a LC-MS/MS analysis using electrospray ionisation in the positive ionisation mode. Fentanyl-d(5) and norfentanyl-d(5) were used as internal standards. The lower LOQ in plasma and urine was 0.1 ng/mL for fentanyl, norfentanyl, alfentanil, remifentanil and 3-methylfentanyl, and 0.2 ng/mL for sufentanil. The method proved linear over a concentration range of 0.2-50 ng/mL for sufentanil and 0.1-50 ng/mL for all other analytes, with correlation coefficients of 0.998 or better. The analytical procedure showed excellent selectivity and precision (all CVs below 15%) for all analytes. Accuracy was good, except for sufentanil, where deviations of more than 15% from nominal concentrations were observed. No matrix effects were observed, and stability of stock and internal standard solutions was within acceptability limits.