Table 1. Empirical Regression Equations for HOOH Concentration–Response Curves.
| compd | equationa | R2 | concn range (nM) | no. of concns tested |
|---|---|---|---|---|
| Cu | Y = 0.524 ln(X) – 0.615 | 0.98 | 3.4–1000b | 11 |
| PQN | Y = 0.0050X | 0.99 | 0–500 | 4 |
| 1,2-NQN | Y = 0.061X | 0.998 | 0–100 | 6 |
| 1,4-NQN | Y = 0.0026X | 0.98 | 0–500 | 4 |
a
Y is the initial rate of HOOH production (μM/h), and X is the concentration of chemical species (nM).
b
HOOH production from Cu goes to zero at 3.4 nM; therefore, HOOH production should be assumed to be zero at Cu concentrations below 3.4 nM. Rates at lower Cu concentrations are indistinguishable from the blank in our experiments.