FIG. 2.

Indirect electrochemical detection of HNO formation by hydroxylamine production. Real-time detection of NH₂OH was performed using an H₂O₂ electrode from WPI on an Apollo 4000 series instrument. We found that this electrode is far more sensitive to NH₂OH than to H₂O₂ (data not shown). NH₂OH was detected in the presence of 100 μM catalase to eliminate interference from H₂O₂. The reaction conditions were as described in Figure 1 except that 1 mM GSH was exposed to varied concentrations of Angeli's salt (0–100 μM). NH₂OH, hydroxylamine; H₂O₂, hydrogen peroxide.