How to implement washing and bolus injection

Similar to the [bolus injection example](How to implement a bolus injection), sometimes a washing event should be modeled.

Such event can be modeled by an additional input function:

INPUTS
Washing   C  nM  conc.  "wash_strength * (1/sqrt(2*pi*wash_duration^2)) * exp(-(t - wash_timepoint)^2/(2*wash_duration^2))"

The function is a scaled normal distribution (given that t indicates the independent variable) with area under the curve given by the value of wash_strength and should be choosen large enough. The washing time point is given by wash_timepoint and the duration by wash_duration.

Additionally, one has to specify a reaction that removes the respective state variable (here Ligand) proportional to the Washing signal:

REACTIONS
Ligand      ->      CUSTOM "Ligand * Washing"

In the folder /Examples we provide some showcase applications Washing_and_Injection_Test that can be used as a starting point for a new modeling project.

In this example a first bolus of 5 nM is injected at time point 30 minutes over a period of 1 minute. At time point 50 minutes Ligand is washed almost completely, and at time point 60 minutes another bolus of 3 nM is injected.