[Simultaneous determination of metals in milk by the ICP-AES technique]

The method of the emission atomic spectrometry with an excitation in the inductively coupled plasma (ICP-AES) has wide range of applications due to the possibility of the simultaneous determination of several elements in various materials. This technique allows to carry out a multi-element analysis at relatively low consumption of the sample which is an additional advantage of the method. In this paper we report an application of the ICP-AES method for a direct determination of the element Al, Cu, Fe, Mn, Sn and Zn in the samples of milk. Several types of pressure mineralization (teflon bomb, sealed quartz tubes) as well as the pressureless technique with the use of the H2SO4, HNO3 and H2O2 agents have been studied. The determinations have been carried out with the use of the Spectroflame M sequential spectrometer with the excitation in ICP plasma made by Spectro Analytical Instruments at the Frequency of 27.12 MHz. The milk samples after mineralization have been diluted to the same volume and directly introduced into the ICP plasma with the help of the pneumatic nebulizer of Meinhard type. On the basis of the obtained results it has been concluded that with an application of the aforementioned mineralization method the average values for the determination of the particular elements are comparable. Generally the most "repeatable" results have been obtained for the sample mineralized in the quartz tubes.(ABSTRACT TRUNCATED AT 250 WORDS)