Dose–Response Curves and the Determination of IC50 and EC50 Values

Abstract

Figure 1. Example dose–response curves for the inhibition of bovine alkaline phosphatase by sodium orthovanadate (169 nM to 100 μM). Assays (200 μL) were conducted in a 96-well plate in 50 mM Tris-HCl, 400 mM mannitol, 6 mM MgCl₂, pH 8.24, 40 μM 4-nitrophenyl phosphate substrate, 1.5% (v/v) DMSO, and 20.2 ng of enzyme per assay. The change in absorbance was monitored at 405 nm. (16) (A). Dose–response curve plotted with log₁₀ [drug (M)] (parametric). (B). The same data plotted with molar drug concentrations (nonparametric). The determined log₁₀ IC₅₀ value is −6.7087, corresponding to an IC₅₀ of 1.95 × 10^–7 M and an h-coefficient of 0.91. Data are means ± SD. This article references 16 other publications. This article has not yet been cited by other publications.