log(F0-F/F)= log Kb + n log[D]t

The above equation involves the statement that free and total drug concentrations are equivalent. To overcome this simplifying assumption and to get a more precise calculation tool, the following new expression has been derived which includes the free drug concentration (in

the second term of the right side)(eqn 3 in attached ppr):

[D]t=(F0-F/F.Kb)^1/n+n[P]t(F0-F/F)

where [D]t and [P]t gives total drug conc and total protein conc. how can one fit this equation? Is there any other paper where this equation has been used?