Determination of lead in the pharmaceutical preparation containing salt by using flow injection hydride generation atomic absorption spectrometry

An analytical procedure using flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) for the determination of lead in dialysis concentrates and calcium supplements was introduced. The parameters such as acidity, concentration of oxidising and reducing agents and argon gas flow rate were investigated to reach the best peak height sensitivity. No significant background signal was observed at high salt concentrations. The detection limit, concentration giving a signal equal to three times standard deviation of the blank signal, was 0.7 ug L"1 for a 500 ul injection volume. Precision of the measurements at the 20 ug L"1 level was 3.7 % RSD. The dialysis concentrates analysed by FI-HG-AAS were found to have 10-70 ug L"1 of lead. The recoveries from the spiked samples were in the range of 92.2-104.9 %. The same samples were analysed by ETAAS after removing the matrix using solid phase extraction with Chelex 100. The results were in agreement with those obtained by FI-HG-AAS.