Exposing cells to H2O2: A quantitative comparison between continuous low-dose and one-time high-dose treatments

► A reaction-diffusion model predicts the behavior of the GOX/CAT system. ► Bolus and low-dose steady-state H2O2 treatments were compared quantitatively. ► Cytosolic H2O2 was monitored through the response of endogenous thiol peroxidases. ► Cytosolic peroxiredoxin-2 oxidation closely mirrors H2O2 influx in real time.