Abstract
Determination of trace metals in blood, serum and plasma presents an important problem of increasing importance from both medical and environmental points of view. For many metals, atomic absorption spectrometry is a method of choice. Nevertheless, a significant obstacle arises because of the lack of availability of proper reference materials, especially ones having the metal content of the order of a few nanograms per milliliter. In our studies dealing with determination of lead, cadmium, cobalt, manganese, aluminium and chromium, calibration with model aqueous solutions and with serum simulating albumin solution was used and the effects of matrix materials were noted. Some improvement may be achieved when matrix modifiers-stabilizers have been used. The often used quantification procedure based on standard addition may also lead to erroneous results because the form in which the analyte is added to the sample does not reflect the speciation in the real samples. This indicates that the problems cannot be considered as completely solved and further studies are indispensable.
