标准加入–原子荧光光谱法测定罐头中的痕量锡

DETERMINATION OF STANNUM IN CAN BY ATOMIC-STANDARD ADDITION FLUORESCENCE SPECTROMETRY

用微波消解处理样品,采用标准加入–原子荧光光谱法测定罐头中的锡。通过实验探讨了样品预处理条件、仪器条件、微波消解程序、还原剂浓度等对锡测定的影响。锡浓度(X)在1～100μg/L范围内与荧光强度(Y)呈线性关系,线性方程为Y=50.15X+12.13,相关系数r=0.9995。用该法对水果和蔬菜罐头样品进行了测定,并进行加标回收试验,回收率为87.5%～102.5%,测定结果的相对标准偏差为2.56%～4.79%(n=11)。

A standard addtion method was established for determination of stannum in can by atomic fluorescence spectrometry, and samples were incinerated by microwave dissolution. The optimal conditions were examined, which included pretreatment condition, instrument condition, programme of microwave dissolution, reducer and acidity of sample. The stannum concentration was linear with its fluorescence intensity in the range of 1-100 μ g/L with correlation coefficient of 0.999 5. The method was used to determine fruit and vegetable samples, and addition recovery experiment was carried out. The recoveries ranged from 87.5% to 102.5%, and the relative standard deviation of determination results was 2.56%-4.79% （ n=11 ）.