ABSTRACT
OBJECTIVE: To study the application of colloidal palladium as a matrix modifier in the determination of lead,cadmium and manganese in whole blood by graphite furnace atomic absorption spectrometry( GFAAS). METHODS: The whole blood samples were diluted 10 times by blood diluents,and then the colloidal palladium was applied as a chemical modifier to improve the ashing and atomizing temperature. The levels of lead,cadmium and manganese in whole blood were determined by GFAAS. The effects of palladium chloride as a conventional matrix modifier were compared. RESULTS: The optimal quantity of colloidal palladium as a matrix modifier was 5. 00 μL. It can raise the ashing temperatures of lead,cadmium and manganese to 900,800 and 1 400 ℃,respectively; and raised their atomizing temperatures to 1 900,1 800,and 2 000 ℃,respectively. Compared to the palladium chloride,the colloidal palladium can provide wider ashing temperature and atomizing temperature of the above 3 elements. The good linearity ranges of lead,cadmium and manganese were 0. 12-100. 00,0. 05-4. 00 and 0. 02-10. 00 μg / L,respectively. All the correlation coefficients were greater than0. 999. The minimum detectable concentrations were 1. 20,0. 50 and 0. 20 μg / L,respectively( samples were diluted 10times). The recovery rates were 99. 2%-104. 0%,102. 8%-105. 5% and 98. 3%-103. 2%,respectively. The relative standard deviations( RSDs) of within-run precision were 1. 2%-2. 6%,2. 7%-5. 3% and 2. 3%-2. 8%,respectively,and the RSDs of between-run precision were 1. 6%-3. 9%,4. 0%-6. 1% and 3. 2%-4. 4%,respectively. CONCLUSION: Colloidal palladium was an excellent matrix modifier in determining the levels of lead,cadmium and manganese in whole blood. It has low background interference and can improve the accuracy and precision of detection.