A HPLC-MS method to detect and quantify guanfacine in urine

作者：Wolf Carl E; Rester Florin Sara J; Poklis Alphonse^*

来源：Clinical Chemistry and Laboratory Medicine, 2012, 50(3): 535-537.

DOI：10.1515/CCLM.2011.803

• attention deficit-hyperactivity disorder (ADHD)
• electrospray ionization
• guanfacine
• HPLC-MS

Background: Guanfacine, an alpha 2-adrenergic (alpha(2A)) agonist long indicated to treat hypertension, is now being used to treat attention deficit-hyperactivity disorder (ADHD) in adolescents. This new therapeutic use may require urine testing to document compliance or abuse. A simple rapid high pressure liquid chromatography-mass spectrometry (HPLC-MS) method to detect and quantify guanfacine in urine following therapeutic administration is presented. %26lt;br%26gt;Methods: Guanfacine and protriptyline internal standard were extracted from alkalinized urine with ethyl acetate. The organic layer was evaporated, reconstituted with mobile phase and analyzed on a YMC Basic S-5 micron, 2.0x150 mm HPLC column connected to an MS detector operated in positive electrospray ionization mode with selected ion resonance. Elution times were %26lt;5 min. %26lt;br%26gt;Results: The analytical measurement range for guanfacine was 20-2000 ng/mL. The limit of detection and quantitation were 5 ng/mL and 20 ng/mL, respectively. Precision as %CV was %26lt;15% at 40, 100 and 500 ng/mL (n=6). Percentage recovery using the same concentrations was %26gt;89%. Interference with drugs and biological constituents was assessed; no interferences were noted. Analysis of 100 random post-diagnostic urine specimens yielded 11 guanfacine positive results with concentrations ranging from 11 to 6390 ng/mL. %26lt;br%26gt;Conclusions: This HPLC-MS method provides a simple and rapid method for the routine detection and quantitation of guanfacine in urine specimens.

• 出版日期2012