DETERMINATION OF CHROMIUM IN HUMAN-SERUM AND PLASMA BY FLAME-LESS ATOMIC-ABSORPTION SPECTROPHOTOMETRY

Concentrations of Cr in serum of overnight fasting volunteers differ over a wide range in the literature. The investigations of the analytical problems of Cr determination by flameless atomic absorption spectrometry underline the necessity of statistical methods for the interpretation of the measurements of Cr in biological matrices. With nine different synthetic chromium complexes the method of standard addition was investigated. Considering the blank values, the limit of detection and the limit of guarantee for purity, Cr was determined in the standard reference material 1569 brewers yeast (National Bureau of Standards) with 45±4 μMol · kg-1 (2.3±0.2μg·g-1), compared with the reference data 41±1 μMol·kg-1 (2.12±0.05 μg±g-1). In serumuuuuu we found a lognormal distribution with the central parameters 13{up triangle, filled}2.2 nMol ·1-1 (0.7{up triangle, filled}2.2 μg·1-1). In plasma the values were in the range between 20 and 30 nMol·1-1 (1-1.5 μg·1-1). The ashing process and the determination are demonstrated and discussed in detail. © 1979 Springer-Verlag.