“…Ion chromatography (IC) has also proven to be useful for both gas-and particle-phase ammonia and amines (Gibb et al, 1999;Hiranuma et al, 2010;Orsini et al, 2003;Praplan et al, 2012;VandenBoer et al, 2011). Formation of an indophenol complex which is measured spectrometrically has been developed for ammonia (Scheiner, 1976;Solórzano, 1969), as have various techniques involving the formation of 1-sulfonatoisoindole followed by fluorescence measurement (Toda et al, 2010;Zhang et al, 1989). For atmospheric ammonia measurement techniques, several intercomparison studies, in both field and laboratory settings, have been reported in the literature (von Bobrutzki et al, 2010;Fehsenfeld et al, 2002;Kirchner et al, 1999;Norman et al, 2009;Schwab et al, 2007;Wiebe et al, 1990;Williams et al, 1992).…”