应用火焰原子吸收光谱法(测定铅、铬、镉)及原子荧光光谱法(测定汞、砷)对灯盏花中重金属的化学形态及其分布进行了研究.0.5 g经过预处理的试样用浓硝酸消解并经高氯酸冒烟至近干,用水溶解残盐并定容为25 mL.在此溶液中分别用上述两方法测定5种金属元素的总量.分别用5种不同萃取溶剂,即乙醇-水(80+20)混合溶液、亚沸重蒸馏水、1 mol·L-1氯化钠溶液、乙酸(2+98)溶液及0.6 mol·L-1盐酸溶液,对10 g试样进行连续超声萃取.各次所得萃取液分别用硝酸和高氯酸按上述方法处理后测定其中5种金属的含量.文中给出了上述金属元素在各种化学形态中的含量及分布状态,此次结果对评价中草药的生物功能及毒性能有参考价值.

FAAS (for determination of Pb,Cr and Cd) and AFS (for determination of Hg and As) were used in the study of chemical species and distribution of the 5 metal elements in the traditional chinese medicine,erigeron breviscapus (EGR-BVCP).0.5 g of the pretreated EGR-BVCP sample was digested with conc.HNO3 and fumed with HClO4 to near dryness.The salts were dissolved and diluted to 25 mL with water,and the solution was used for determination of total amount of the 5 metal elements.For separation of different chemical species of these metal elements,successive ultrasonic extractions of a 10 g portion of the sample were performed by using 5 different extractants,i.e.,ethanol-H2O(80+20) mixture,sub-boiling re-distilled water,1 mol·L-1 NaCl solution,acetic acid (2+98) solution and 0.6 mol·L-1 HCl succeedingly.The extracts obtained in each extraction was treated with HNO3 and HClO4 as described above and the contents of the 5 metal elements,were determined by the same methods.Data of amount of the metal elements in various chemical species were given in detail,which are valuable for evaluation of biological function and toxicity of the traditional Chinese medicines.