Determination of fentanyl in sweat and hair of a patient using transdermal patches.

Fentanyl is a synthetic opioid used to treat intense chronic pain. In this study, the authors report detection and quantification of fentanyl in sweat and hair of a patient receiving fentanyl (25 microg/h) via a transdermal therapeutic system (TTS) for 22 days. Sweat was collected using sweat patches every night on days 13-21 of the therapy, and hair was collected 12 weeks after the end of the treatment.

Quantification of lorazepam and lormetazepam in human breast milk using GC-MS in the negative chemical ionization mode.

Lormetazepam (Loramet is a benzodiazepine mainly used as an hypnotic to treat insomnia. Lorazepam (Temesta) is used as an anxiolytic, tranquilizer, sedative, and anticonvulsant, and it is the major metabolite of lormetazepam. In this study, we designed a method to simultaneously detect and quantify these substances in human breast milk.

Determination of nevirapine and efavirenz in plasma using GC/MS in selected ion monitoring mode.

An accurate, selective, and sensitive method for the determination of the nonnucleoside reverse transcriptase inhibitors (NNRTIs) nevirapine (nvp) and efavirenz (efv) in human plasma using gas chromatography-mass spectroscopy in selected ion monitoring mode (GC/MS-SIM) was developed. Solid-phase extraction (SPE) gave extraction yields near 100% for both nvp and efv, and calibration curves were linear over the therapeutic concentration ranges. Variation of intraday and interday precision was below 5%.