Determination of Nitrate, Sulfate and Oxalate Ions in Vegetables by Single Column Ion-Chromatography.

Determination of Nitrate Ion Concentration in Fresh Vegetable Juices Using Ion-Pair Ultra Performance Liquid Chromatography (IP-UPLC)

“…conditions result in an overlap of nitrate and oxalate ion peaks. When 1.0 mM phthalic acid at pH 4.0 was used as the eluent (Yasui et al 1992), the nitrate and citrate ion peaks overlapped. Changing the pH of the IC eluent from 4.0 to 4.3 separated the nitrate and citrate ion peaks (Ito et al 2005).…”

New Ways to Evaluate the Quality of Vegetables Using Instruments

“…However, the conditions of IC 31 could be applied when few citrate ions were detected because the peak of the nitrate ions overlapped that of the citrate ions. When the pH of the eluent changed from 4.0 to 4.3, citrate and nitrate ions were separated without interference 25 .…”