The analytical method develop for the separation and determinations of the two carboxylic acids (formic and
acetic) was realized on a Dionex ICS-5000+ Ion chromatograph model, with integrated eluent generator, a
conductivity detector and anion suppressor model 500 ORSA Dionex 2mm.
To separate the acids, an IonPac AS-18 column chromatography coupled with a precolumns recommended by the
manufacturer to determine anions and low molecular weight organic acids were used.
Elution mode was isocratic, and consisted of 10 mM of KOH as eluent. The thermostatic column was set at 20 °C
and the injection volume was 5μl; the total running time of the method was 10 minutes.
The calibration curves were realized using external standard method. For this porpoise, analytical standards were
purchase from LGC Standards, and consisted in 1000 mg/mL acetate and 1000 mg/mL formate.