Time Dependent Inhibition Using the IC50 Shift ApproachThis assay is used to identify time-dependent inhibition of individual cytochrome P450 (CYP) enzymes by a test compound using the IC50 shift approach Catalog number EA431 Required from Customer Deliverables Calculated IC50 shift (-NADPH/ +NADPH)Substrate Assay System   Assay Conditions Assay QC Notes
  1. IC50 values are estimated by fitting the experimental data (percent of control activity remaining at each concentration of test compound or positive control) to a sigmoidal model and non-linear regression analysis.
Individual CYP Substrates and Positive Control Inhibitors 
CYP Isoform Probe Substrate Metabolite Positive Control Inhibitor
1A2 Phenacetin Acetaminophen Furafylline
2A6 Coumarin 7-OH coumarin 8-Methoxypsoralen
2B6 Bupropion Hydroxybupropion Thio-TEPA
2C8 Amodiaquine Desethylamodiaquine Gemfibrozil Glucuronide
2C9 Diclofenac 4’-OH diclofenac Tienilic Acid
2C19 S-mephenytoin 4’-OH mephenytoin Ticlopidine
2D6 Bufuralol 1’-OH bufuralol Paroxetine
2E1 Chlorzoxazone 6-OH chlorzoxazone Diethyldithiocarbamate
3A4 Testosterone 6β-OH testosterone Troleandomycin
3A4 Midazolam 1’-OH midazolam Troleandomycin