Figure 7.

Minimum values of 1/(K_a1[A]) that can be used in frontal analysis experiments to produce a given deviation from linearity in double-reciprocal plots for three-site systems at various combinations of affinities and various mole fractions of the highest affinity site (α₁) when the mole fraction for the second highest affinity site (α₂) is equal to 0.25. The mole fraction of the lowest affinity site (α₃) was calculated by using α₃ = 1 - α₁ - α₂; the x-axis extends in this case up to 0.75, which is the maximum allowed value for α₁ if α₂ is equal to 0.25. The affinities for the binding sites that were used in these calculations were (a) β₁ = 1.00, β₂ = 0.10, and β₃ = 0.05; (b) β₁ = 1.00, β₂ = 0.25, and β₃ = 0.125; and (c) β₁ = 1.00, β₂ = 0.50, and β₃ = 0.25. These results were generated by using a modified form of eq. (10) that was based on eqs. (6)-(7) and developed for a three-site system.