为了验证激光诱导击穿光谱技术对中药内重金属铜元素检测的可行性, 以黄连、附片、茯苓作为检测对象, 分别为其配制了一系列浓度不同的含铜样品。采用1 064 nm的纳秒脉冲激光器作为激发光源, 八通道光谱仪进行光谱采集。选用Cu 324.7 nm作为特征谱线进行分析, 实验确定最佳延迟时间为0.5 μs。根据黄连、附片、茯苓的不同基体情况分别选取适当内标参量进行定量分析, 所得线性拟合度分别为0.986,0.931,0.975, 并与直接定标所得结果进行了对比。实验结果表明, 内标法可提升拟合精度, 激光诱导击穿光谱技术可用于中药重金属铜元素污染的快速检测。

In order to verify the laser induced breakdown spectroscopy (LIBS) is feasible for the detection of heavy metal elements in Chinese traditional medicine, using coptis chinensis, aconite root and poria cocos as detection object, a series of Cu element samples with different concentrations were prepared. 1 064 nm Nd: YAG solid pulse laser was used as the excitation source, the eight channel spectrometer was used for spectral data acquisition. Cu 324.7 nm was selected as characteristic spectral line, and the optimal delay time was determined for 0.5 μs. According to the different substrate conditions of coptis chinensis, aconite root and poria cocos, the appropriate internal standard parameters were selected, and the linear degree was 0.986, 0.931, 0.975, respectively. The results were compared with the results of direct calibration. The experiment results show that the internal standard method can improve fitting accuracy and LIBS can be used for the rapid detection of heavy metal Cu pollution of traditional Chinese medicine.