Sodium, Potassium, Calcium, and Magnesium belong to the essential mineral substances in the human organism. These elements take influence in the generation of enzymes and hormones, control the osmotic pressure in tissues and body fluids and are important for the exchange procedures in the cell membranes.
In this application, the control of Na, K, Ca and Mg in a variety of mineral waters has been performed according to the actual DIN/ EN regulations, with the Shimadzu atomic absorption spectrophotometer AA- 7000 in a fully automatic multi element sequence.
The AA-7000 in combination with the ASC-7000 sample preparation station allows the automated flame micro sampling method. In this method, the flame atomic absorption analysis is conducted with small sample volumes (2 – 90 μL), while in the conventional flame method (hereafter “flame continuous method”), the sample is continuously aspirated with a flow rate of approximately 8 ml/ min and larger sample volumes are needed for aspiration.
The flame micro sampling method has several advantages over the flame continuous method: analysis is possible with a small amount of sample, and when the autosampler is used, automatic dilution of the sample and automatic addition of buffer solutions are possible in order to compensate interferences. Moreover, since only a small amount of sample is introduced, the flame micro sampling method is effective for analysis of high matrix samples which may cause clogging of the burner in the flame continuous method. So the method is the right choice for determination of alkaline and alkaline earth elements in mineral water.