Quantification of Selective Serotonin Reuptake Inhibitors

Fluoxetine hydrochloride (CAS# 56296-78-7), Paroxetine hydrochloride hemihydrate (CAS# 110429-35-1), Sertraline hydrochloride (CAS# 79559-97-0), dimethyl sulfoxide (CAS# 67-68-5), tricaine methanesulfonate (CAS# 886-86-2), and water (sterile filtered, Bioreagent grade) were purchased from Sigma-Aldrich Canada (Oakville, ON, Canada). Working stocks of Fluoxetine hydrochloride and Paroxetine hydrochloride hemihydrate were made by dissolving the powders in water at 10 and 5 mg/mL, respectively. Sertraline hydrochloride was dissolved in dimethyl sulfoxide (DMSO) at 10 mg/mL. These stocks were stored at 4°C. Methanol used in SSRI extractions was distilled-in-glass grade (Caledon Laboratories Ltd., Georgetown, ON, Canada). Mobile phases used in the liquid chromatography–high resolution mass spectrometry (LC-HRMS) were prepared with deionized water obtained from a Milli-Q system and LC-MS grade acetonitrile and LC-MS grade formic acid (Fisher Chemical, Ottawa, ON, Canada).