顺序注射氢化物发生-原子荧光光谱法同时测定中草药中As和Bi

建立了一种顺序注射氢化物发生-原子荧光光谱法同时测定中草药中的As和Bi含量的方法,考察了光电倍增管负高压、As和Bi灯电流、原子化器高度、载气流量、屏蔽气流量等因素对测定结果的影响。结果表明,载流HCl的浓度为0.3 mol/L,KBH4质量浓度为10 g/L时,同时测定As和Bi的效果最佳;在最佳实验条件下,As和Bi的检出限分别为0.058μg/L和0.006μg/L,加标回收率为94.6%~103.2%,相对标准偏差小于3.0%,中草药试样中共存的离子对As和Bi的测定没有干扰。该法操作方便、快速,用于中草药中As和Bi的同时测定,具有很好的可行性和实用性。

Determination of Arsenic and Bismuth in Chinese Herbal Medicine by Sequential Injection-HG-AFS

A method used for simultaneous determining of arsenic and bismuth of chinese herbal medicine by sequential injection - hydride generation （HG） - atomic fluorescence spectrometry （AFS）was established. The influence of instrument parameters such as the negative high voltage on the photomuhiplier, current of lamp, carrier gas rate, shield gas rate on the determination of arsenic and bismuth etc were studied. The result showed that when the concentration of hydrochloric acid and potassium borohydride were 0. 3 mol/L and 10 g/L respectively, the performance of determination of arsenic and bismuth was best. Under this conditions, the detection limits of arsenic and bismuth were 0. 058 μg/L and 0. 006μg/L respectively. The recovery rate with added specimen for arsenic and bismuth were between 94. 6% and 103.2%. The value of RSD was less than 3.0%. There was not any interference of the coexistence ions in determined chinese medicine samples for the determination of arsenic and bismuth. This method is easy and sensitive. It is feasible and practicable to determine arsenic and bismuth in chinese herbal medicine.