Table 1.
One-Site Model | Two-Site Model | Three-Site Model | |
---|---|---|---|
Ka1 (M−1) | 2.0 (± 0.1) × 105,b | 1.3 (± 0.2) × 105 | 3.6 (± 5.9) × 105 |
mL1 (mol) | 1.9 (± 0.1) × 10−8,b | 2.4 (± 0.1) × 10−8 | 9.0 (± 15.4) × 10−8 |
Ka2 (M−1) | 3.5 (± 3.0) × 102 | 4.9 (± 6.5) × 104 | |
mL2 (mol) | 9.3 (± 5.5) × 10−8 | 1.9 (± 1.3) × 10−8 | |
Ka3 (M−1) | 4 (± 39) × 101 | ||
mL3 (mol) | 5 (± 44) × 10−7 | ||
Correlation coefficient |
0.964c | 0.998 | 0.998 |
Sum of residuals squared |
2.2 × 10−16,c | 1.2 × 10−17 | 9.2 × 10−18 |
All of these parameters are for data obtained at pH 7.4 and 37 °C. The values in parentheses represent a range of ± 1 S.D (n = 15), as based on regression using Excel and the linear region of a plot made according to Eqn. (1) for a single-site model or the standard error as calculated by DataFit for a fit made according Eqn. (4) for a two-site or a similar expanded expression for a three-site model.
The Ka1 and mL1 values given for the one-site model were estimated from the linear region of a plot made according to Eqns. (1) or (5).
The correlation coefficient and sum of residuals squared given for the one-site model are for a fit of the entire data set to Eqn. (2).