石墨炉原子吸收法测定生物体液中有机锗

DETERMINATION OF GERMANIUM IN BIOLOGICAL FLUIDS BY GFAAS

本文研究了石墨炉原子吸收光谱法测定人及动物口服丙氧锗二酸(Ge-132)后血浆及尿中锗浓度的方法。样品无需预先处理,加入Triton X-100后,可直接测定。为排除未消化生物样品对测定的干扰,本法对基体改进剂硝酸镍及硝酸钙的作用进行了比较,认为硝酸镍虽可明显提高水溶液中锗的吸收值,但对血浆中锗的影响不如硝酸钙,且镍浓度的变化对锗吸收的影响也较大,约需3～4mg/ml为宜。而钙剂对血浆及水溶液中锗的影响近似,含钙量大于0.5mg/ml均可获得相同的效果。残留在石墨炉中碳渣的影响不可忽视。本文采用通氧的办法消除了影响。本法绝对灵敏度为34pg/0.0044A,检出下限为1.6×10^(-9)g,线性范围0～200ng/ml Ge,变异系数(4个浓度)1.46～3.1%(n=10),回收率(4个浓度)为95.5～102.6%。

A graphite furnace atomic absorption spectrometric method for the quantitative analyses of Germanium in plasma and urine is described. The analyses were performed after adding Triton X-100 into plasma without sample preparation. For the purpose of eliminating the interference of the unpretreatment samples in the determination, the effet of matrix modifier had been tested by comparing Ni(NO_3)_2 with Ca(NO_3)_2. The results indicated that the absorption of Ge in plasma did not increase as much as Ge in water, although Ni(NO_3)_2 could evidently increase the signal of absorption of Germanium in water solution, and also the absorption of Ge was affected by the variation of the concentration of Ni(NO_3)_2. The limits were very narrow about 3-4 mg/ml Ni^(++). However the effects of Ga(NO_3)_2 for Ge in plasma were similar to that in water, the levels of>0.5 mg/ml Ga(NO_3)_2 could obtain the same increasing effects. The limit of detection was 1.69×10^(-9)g. The absolute sensitivity was 34 Pg/0.0044A. The linear range was 0—200 ng/ml. The precision of the assay (C.V.) was 1.46—3.1% (n=10). The recovery was 95.5—102.6%. Now we have finished the determination of the preclinical animals and phase I clinical test of Ge-132 with this method.