[Determination of thallium in the urine with colloidal palladium as the matrix modifier by graphite furnace atomic absorption Spectrometry].

To instruct a method of determining thallium in the urine by graphite furnace atomic absorption spectrometry(GF-AAS) with colloidal palladium as the matrix modifier. Urine samples were first diluted and then determined by GF-AAS with colloidal palladium while using thermal sample injection. The optimum volume of colloidal palladium was 6 μl and the best ashing temperature was 600-800 ℃ while the atomization temperature was 1700-1900 ℃ . This method showed a good linearity relationship when the concentration between 0.33 and 50.0 μg/L while the correlation coefficient of standard curve line was 0.9992, and the detection limit was 0.33 μg/L and the recovery rate was between 92.7% and 102.3% with the intra-day precision in the range of 2.55% to 3.66% and the inter-day precision in the range of 1.77% to 3.85%. This method has the advantages of low detect limit, high sensitivity and good precision, and it can be used in the biological monitoring and emergency detecting of workers exposed to thallium.