B DETERMINATION OF SODIUM BY ICP-OES

1 Solutions with sodium compounds are nebulised into an argon plasma, where all components are vaporised. Sodium compounds are dissociated and excited, and then emit radiation of which the intensity is measured at a wavelength of 589.592 nm. 

1 This procedure yields a standard curve that is linear up to at least 60 mg/L Na. 

2 The detection limit is approximately 0.005 mg/L in the digest. The determination limit is approximately 0.015 mgfL (0.07 respectively 0.22 mmol/kg in the dried plant material). 

1 The reproducibility of determinations by this procedure should give, at reasonable control and thorough sample preparation, a coefficient of variation within 5 %. 

1 Inductively coupled plasma optical emission spectrometer. 

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