Determination of copper in human seminal plasma by graphite furnace AAS using tungsten probes

摘要

A method is described for the determination of low-level copper concentrations in human seminal plasma by Graphite Furnace Atomic Absorption Spectrometry. Tungsten probes are used to introduce the undigested seminal plasma samples into the graphite tube and they are also used as the atomization surfaces for the attached sample. For comparison purposes, acid-digested samples, introduced by means of an autosampler, are analyzed. The difference between the values obtained after analysis of the digested portions of each sample ranges between 2.8 and 5.6%. Considerably better sensitivity (8.2 pg of Cu with digested sample vs. 2.4 pg with the probe) and limits of detection, taken as three times die standard deviation (11.2 pg of Cu with digested sample vs. 4.8 pg with the probe), were obtained using the probe. The non-heterogeneous distribution of copper in this particular matrix when undigested samples are analyzed reduces reproducibility. However, reproducibility can be improved by ultrasonic stirring of the seminal plasma prior to analysis. [References: 13]