DETERMINATION OF COPPER BY ETA-AAS

1 Copper ions in the digest are subsequently dried, ashed and vaporised by electrical heating in a graphite furnace. The copper atoms thus formed absorb radiation from a hollow cathode lamp. The absorbance is measured at a wavelength of 327.4 nm. 

1 This procedure yields a standard curve that is linear up to approximately 50 pg/L Cu. 

2 The detection limit is approximately 1.2 pg/L in the digest The determination limit is approximately 3.6 pg/L (0.4 respectively 1.2 mg/kg in the dried plant material). 

1 To avoid interferences as much as possible, background correction is necessary (e.g. Zeeman background correction). 

Whereas the flame AAS determination normally uses 324.7 nm as wavelength for measurement, the graphite furnace determination has at 327.4 nm an improved curve 

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