采用石墨炉原子吸收光谱法(GFAAS)测定了中药虎杖中镉的含量,对基体改进剂NH_4H_2PO_4的用量、灰化温度、原子化温度等实验参数进行了优化。实验结果表明,加入NH_4H_2PO_4不仅能提高测定的灵敏度,还能有效消除共存离子的干扰,在选定的实验条件下,分析测定了中药虎杖中镉的含量,回收率为96.5%—102.2%,检出限为0.072μg·mL~(-1),线性范围为0—0.2ng/mL。 The content of cadmium in Polygonum cuspidatum was determined by graphite furnace atomic absorption spectrometry (GFAAS), and the experimental parameters of substrate modifier NH4H2PO4, ashing temperature and atomization temperature were optimized. The experimental results showed that the addition of NH_4H_2PO_4 could not only increase the sensitivity of determination, but also effectively eliminate the interference of coexisting ions. Under the selected experimental conditions, the content of cadmium in Chinese knotweed rhizome was determined and the recovery was 96.5% -102.2% The limit was 0.072 μg · mL -1 and the linear range was 0-0.2 ng / mL.