LC–MS determination of fentanyl in human serum and application to a fentanyl transdermal delivery pharmacokinetic study

Aim: Fentanyl is an opioid agonist used for acute and chronic pain management. In this report, a highly sensitive and simple LC–MS/MS method using Hydrophilic Interaction Chromatography (HILIC) column was validated and used for fentanyl quantification in human serum. Results: The isocratic mobile phase was composed of acetonitrile: 10 mM ammonium formate buffer (pH = 3.2; 90:10, v/v). The assay was linear over a concentration range of 10–10,000 pg/ml. The accuracy of the validation method ranged from 93.2 to 107%, and the precision was within 6.4%. Fentanyl was stable during short- and long-term storage. Conclusion: The assay has been successfully applied to serum samples obtained from healthy subjects of a fentanyl transdermal pharmacokinetic study.