*2.5. Ammonia Quantification*

Fresh solutions of sodium hypochlorite (2.5% in water), sodium citrate (0.38 mM in 0.46 mM aqueous solution of NaOH), and sodium salicylate (2.75 mM in water containing 9.39 μmol of sodium nitroprussiate) were prepared prior to the ammonia quantification. To a microtube containing 250 μL of the hypochlorite solution and 250 μL of citrate/NaOH solution, the 100 μL aliquot from the reaction was added, followed by the addition of 300 μL of the sodium salicylate solution. After mixing, the reaction was allowed to proceed for 15 min at room temperature. The reaction was analyzed by UV–Vis spectroscopy at 654 nm. Quantification of ammonia was performed by using a calibration curve with seven measurements and R<sup>2</sup> = 0.99, using ammonium chloride as standard.
