Saturation (Michaelis–Menten)
A rise that levels off at V. Use it for enzyme kinetics, with reaction rate against substrate concentration, and for binding and other saturating responses.
Fit the example dataStart with your own data
Example: simulated initial rates of an enzyme-catalysed reaction, 11 points with y uncertainties, opened as a new copy you can edit.
Parameters
- Maximum: the plateau y approaches at large x (Vmax in enzyme kinetics).
- Half-saturation constant: the x at which y = V/2 (the Michaelis constant Kₘ).
Tips
- The model is undefined at x = −K, so keep that value outside your data.
- Include points well above K so the plateau is determined; with data only at low x, V and K are strongly correlated.
- Fit the rates themselves rather than a double-reciprocal (Lineweaver–Burk) plot, which distorts their uncertainties.