目的建立快速、准确、灵敏的微波消解——石墨炉原子吸收光谱法,用于茶叶中镉的测定。方法样品中加入硝酸进行微波消解,加入磷酸二氢铵作为基体改进剂以改善峰形和灵敏度,用石墨炉原子吸收光谱法进行镉含量的测定。结果在优化的最佳消解条件和检测条件下,该方法具有很好的灵敏度,试验的RSD为1.5%~4.1%,回收率为96.3%~97.7%,检出限为0.012μg/L。结论该方法具有灵敏度高、检出限低,共存干扰少、稳定性好、回收率高等特点,是测定茶叶中镉含量的可靠方法。 Objective To establish a rapid, accurate and sensitive microwave digestion - graphite furnace atomic absorption spectrometry for the determination of cadmium in tea. Methods Nitric acid was added into the sample for microwave digestion. Ammonium dihydrogen phosphate was added as matrix modifier to improve the peak shape and sensitivity. The content of cadmium was determined by graphite furnace atomic absorption spectrometry. Results Under the optimized conditions of digestion and detection, the method had good sensitivity. The RSD of the method was 1.5% -4.1% and the recovery was 96.3% -97.7%. The detection limit was 0.012 μg / L. Conclusion The method has the characteristics of high sensitivity, low detection limit, less coexistence interference, good stability and high recovery. It is a reliable method to determine the content of cadmium in tea.