原子吸收法测定中药黄芩中不同化学形态的Cu、Zn、Fe和Mn

Determination the Chemical Speciation of Cu,Zn,Fe and Mn in Radix Scutellariae by AAS

研究用原子吸收光谱法(AAS)测定中药黄芩水煎液中Cu,Zn,Fe和Mn化学形态的分析方法。水煎液经0.45μm滤膜过滤后分为悬浮态和可溶态组分试样;对于可溶态组分试样,采用LSA-10大孔树脂将其分为有机态和无机态组分试样,并采用正辛醇-水分配体系,在模拟人体胃肠环境条件下,将水可溶态中待测元素分离为醇溶态和水溶态,然后用AAS测定上述各组分试样中待测元素的含量,即可给出比现有的仅测量中药黄芩中上述各待测元素总量为多的信息。该法待测元素Cu,Zn,Mn的检出限(3倍空白标准差)为0.01μg.mL-1,Fe为0.02μg.mL-1,精密度(RSD,n=11)为1.5%～3.6%,对可溶态和无机态组分试样进行加标测定的回收率为96.7%～105.0%。所得结果对黄芩的综合研究有重要的实际意义。

An analysis method was developed to determine the chemical speeiation of Cu, Zn, Fe and Mn in radix scutellariae decoction using atomic absorption spectroscopy（AAS）. The decoction can be divided into suspension and soluble species by 0. 45 tan filter membrane and the soluble species can be separated into organism and inorganic species by LSA-10 macroporous resin. These elements in water-soluble test samples can be divided into alcohol-soluble and water-soluble by adopting n-oetyl alcoholwater allocation system in man-made gastric acidity. Then, the concentration of these elements was determined by AAS, which provided more chemical speeiation information about these elements instead of the total amount of them only in radix scutellariae. Detection limit of Cu, Zn and Mn by using the method was all 0. 01 μg · ml^-1 and was 0. 02 μg · ml^-1 for Fe. The RSD was in the range of 1.5%-3.6%（n=11） and the recovery rate of soluble species and inorganic species were in range of 96. 7%- 105. 0%. The method has been successfully applied to determine the ehemieal speciation of Cu, Zn, Fe and Mn in radix scutellariae, whieh was very important for overall study of radix scutellariae.