Cat- and anion concentrations in fermentation samples and pulp hydrolysates were analyzed by ion chromatography . For quantification of cations, 25 lL of sample volume was added on an IonPac CS 16 column For quantification of anions, 25 lL of sample volume was added on an IonPac AS9-HC column and eluted isocratically with 1.2 mL min1 of 9mM Na2CO3 at room temperature. Detection of cat- and anions was carried out by a conductivity cell. Each analysis was carried in duplicate and peak areas were compared to analyses of known concentrations of salt-solutions consisting of cat- and anions of interest. The mean concentration of two analyses is presented.