Suspension Sample Introduction for FAAS Determination of Calcium and Magnesium in Powdered Walnut

Technique of suspension sample introduction was applied to the flame atomic absorption spectrometric determination of Ca and Mg in powdered walnut. The sample of powdered walnut was prepared by suspending the powder into an agar solution. The prepared suspension was then directly nebulized and carried into the air acetylene flame. The determination of Ca and Mg was carried out by calibration with standard additions. Analytical results of the suggested method were compared with those of the ashing method. As verified by t-test,no significance difference was found between the two methods at the level of a=0.05. Values of RSD′s of the method were <4.5%. Detection limits of this method were found to be 0.11 mg·L-1 (for Ca) and 0.045 mg·L-1 (for Mg).