悬浮液进样——火焰原子吸收光谱法测定中草药中的钾

Determination of potassium in Chinese medicinal herb by suspension sampling flame atomic absorption spectrometry

目的 :测定中草药中的钾。方法 :将样品烘干、磨细、过筛 ,制成琼脂悬浮液。取一定量悬浮液 ,加入NaCl溶液以消除电离干扰 ,而配制成试液。将试液喷入空气 乙炔火焰 ,用工作曲线法测定。结果 :测定结果与灰化法一致 ,相对误差小于± 0 .6 % ,t检验表明 ,两种方法之间无显著性差异。结论 :本方法简便、准确。可以用悬浮液进样法取代灰化法处理样品 ,以火焰原子吸收光谱法测定中草药中的钾。

OBJECTIVE:To determine potassium in Chinese medicinal herb.METHOD:The samples were stoved,grinded down,sieved and then made into agar suspension.Test solutions were prepared by adding NaCl solution to appropriate amounts of the suspension to eliminate ionization interference.The test solutions were injected into air acetylene flame.Standard calibration method was used to calculate potassium.RESULTS:Analytical results were consistent with those obtained by ashing method.The relative errors were less than ±0.6%.The t test showed that no difference was found between those two methods.CONCLUSION:This method is convenient and accurate.It is possible to replace the ashing method by suspension sampling method for the determination of potassium in chinese medicinal herb by flame atomic absorption spectrometry.