Simultaneous determination of total sodium, potassium, magnesium, and calcium in plant tissues using acid digestion and ion chromatography

Sodium, K, Mg, and Ca in plant tissue were measured by single column ion chromatography (SCIC) as an alternative to traditional methods such as atomic absorption spectrophotometry (AAS) or inductively coupled plasma-atomic emission spectrophotometry (ICPAES). Interference of the NH 4 peak on the Na peak in SCIC was eliminated by removal of NH 4 ions by drying the nitric-perchloric acid plant digest at 350 °C. Cations were separated using an IC-Pack CM/D column with 0.1 mM EDTA + 3 mM HNO 3 as eluent. Inclusion of 10% (v/v, ≃ 1.89 M) acetonitrile in the eluent shortened the retention time of divalent cations by 22% compared with the time without acetonitrile [...]