Abstract
Cu, Zn, and Se were successfully determined in a few microliters (<100 mu l) of biological samples using discrete injection atomic absorption spectrometry. Different factors were investigated in order to obtain a biological sample volume which is valid for analysis. Among them are the effect of microsampling volume variations (starting from 40 to 200 mu l), nebulization efficiency, detection limits, precision, and finally the calibration and sensitivity of the proposed method. It was found that 60 mu l of the biological sample was adequate for the quantitative analysis with reasonable precision. The advantages of the proposed method are not only rapidity, simplicity, sensitivity, and good precision, but also, contrary to conventional flame atomic absorption spectrometry, the capability of analyzing microvolumes of samples.