采用微波消解法消解中药样品,以L-半胱氨酸作为预还原剂与掩蔽剂,利用氢化物发生-原子荧光光谱法测定中药中痕量锑的含量;优化了仪器的工作条件以及样品酸度、载流酸度、硼氢化钾的用量等因素对荧光强度的影响;在最佳工作条件下,锑的质量浓度与荧光强度在10 μg·L-1以内呈线性关系,检出限达(3S/N)到0.038 4 μg·L-1.测定了两种中药样品中的锑量,5次测定的平均值分别为0.083及0.038 μg·g-1,其相对标准偏差依次为3.69%及4.12%.在两种已测定其锑量的中药样品中分别加入锑标准溶液作回收试验,测得回收率为96.0%.

HG-AFS was applied to the determination of trace amounts of antimony in traditional Chinese medicines (TCM).Sample of TCM was soaked in conc.HNO3 overnight,and then digested in a microwave oven with supplementary addition of H2O2.A solution of L-cysteine was added to the sample solution as reductant and masking agent.Working condition of the instrument and factors influential to fluorescence intensity,i.e.,acidity of sample solution and carrier solution,and amount of potassium borohydride added,were studied and optimized.Linear relationship between values of fluorescence intensity and concentration of antimony was obtained within 10 μg·L-1.Detection limit (3S/N) of the method found was 0.0384 μg·L-1.Test for precision was made by analyzing 2 TCM samples with 5 determination for each sample,giving average value of antimony 0.083 and 0.038 μg·g-1,and values of RSD′s 3.69% and 4.12% respectively.Test for recovery was made by adding standard Sb(Ⅲ) solution to samples with known Sb content,and values of recovery obtained were 96.0%.Twelve kinds of TCM samples were analyzed for antimony content by the proposed method.