Table 2.
Local association equilibrium constants obtained for glibenclamide at specific binding regions of normal HSA and glycated HSA at 37°C and pH 7.4a
| Type of HSAb | Association equilibrium constant, KaI | ||
|---|---|---|---|
| Sudlow site I, (× 104 M−1) | Sudlow site II (× 104 M−1) | Digitoxin site (× 106 M−1) | |
| Normal HSA | 2.4 (± 0.3) | 3.9 (± 0.2) | 2.1 ± (0.8) |
| gHSA1 | 2.5 (± 0.1) | 16.7 (± 0.4) | 1.7 ± (0.8) |
| gHSA2 | 4.1 (± 0.7) | 23.3 (± 0.8) | 1.1 ± (0.4) |
| gHSA3 | 4.5 (± 0.3) | 17.8 (± 0.4) | 1.2 ± (0.2) |
a
The values in parentheses represent a range of ±1 S.D., as based on error propagation and the precisions of the best-fit slopes and intercepts obtained when using Eq. (6) for n = 5–8.
b
gHSA1, gHSA2, and gHSA3 refer to glycated HSA samples with different levels of glycation, as described in more detail in Section 2.3.