Materials
Ivermectin (IVM-B1a > 95%, IVM-B1b < 2%) was purchased from Sigma-Aldrich (Saint Louis, MO, USA). IVM-B1a (95% purity) was purchased from Toronto Research Chemical (Toronto, ON, Canada). IVM-B1b (99.27% purity) was purchased from Clearsynth (Mississauga, Ontario, Canada). Pooled human liver microsomes (50 donors, GibcoTM) were purchased from Thermo Fisher Scientific (Waltham, MA, USA). Cryopreserved primary human hepatocytes (M00995-P, UBV donor) and hepatocyte culture medium (InVitroGroTM CP Medium) were purchased from BioIVT, Inc (Baltimore, MD, U.S.A.). Human cytochrome P450 cDNA-expressed (Supersomes™) isoforms (CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C18, CYP2C19, CYP2D6, CYP2E1, CYP3A4, and CYP3A5), NADPH regenerating system, insect cell microsomes (negative control), and human P450 oxidoreductase +b5 were purchased from Corning (Corning, NY, USA). LC-MS grade water and acetonitrile were purchased from J.T Baker (City, PA, USA). LC-MS grade ammonium acetate and formic acid were purchased from Sigma-Aldrich (Saint Louis, MO, USA). HPLC grade organic solvent for NMR analysis was purchased from Sigma Aldrich (Saint Louis, MO, USA). CD3CN 99.8% and CDOOD 98% was purchased from Deutero GmbH (Kastellaun, Germany). Water for NMR was prepared from a Milli-Q purification system from Merck (Darmstadt, Germany).