Fig. 5.

Oxidation of F₄₂₀H₂ by nitrogen dioxide gas under anaerobic condition. (A) To 1 mL of an anaerobic 25 μM F₄₂₀H₂ solution in 50 mM potassium phosphate buffer (pH 7.0) in a 3-mL quartz cuvette, nitrogen dioxide gas was added by using a gas-tight syringe. The UV-visible spectrum of the solution was recorded before NO₂ addition and then after each addition of 250 μL of (10.22 nmol) NO₂. (B) Relationship between NO₂ added and F₄₂₀ generated. Note: Most of the NO₂ added was likely converted into NO₂⁻ and NO₃⁻.