文摘
Physiological level of trace lithium in human serum was determined by graphite furnace atomic absorption spectrometry (GFAAS). 3.5 % HNO3 (v/v) was employed as a protein precipitant for sample treatment and at the same time verified as a very effective chemical modifier to eliminate the interference of chloride. The analytical conditions for lithium determination in serum were investigated and the optimal pyrolysis and atomization temperatures were 800 °C and 2700 °C. The accuracy and precision of the method were tested by determining lithium in a RANDOX HN1530 assayed human multi-sera and a pooled human serum. The result was in good agreement with the target value and CV of the pooled human serum was 4.74 % (n = 10). The characteristic mass, the limit of detection (LOD) of the proposed method were 0.8 pg and 0.01 μmol/L, respectively. Median ± S.E.M. of serum lithium in 220 Chinese people was 0.25 ± 0.02 μmol/L.