Modeling the Effect of Binding Kinetics in Spatial Drug Distribution in the Brain

Table 1

The model parameters, descriptions, values, and units.

Parameter	Description	Value[reference]	Unit
	Drug bioavailability	1 [2]	—
	Concentration of orally delivered drug	[2]
	Distribution volume	[2]
	Absorption rate constant	[2]
	Elimination rate constant	[2]
	Brain capillary radius	[28]
	Inter-capillary distance	[29]
	Brain capillary blood flow rate	[29]
	Maximum active influx rate	[assumed]
	Maximum active efflux rate	[assumed]
	Concentration required to attain half of	[2]
	Concentration required to attain half of	[2]
	Effective diffusion coefficient	[20]
	Brain ECF bulk flow velocity	[assumed]
	Surface area of the BBB	[assumed]
	BBB permeability	[2, 8]
	Specific association rate constant	[30]
	Non-specific association rate constant	[23]
	Specific dissociation rate constant	[30]
	Non-specific dissociation rate constant	[23]
	Total concentration on specific binding sites	[23]
	Total concentration on non-specific binding sites	[23]