ICP-MS Method Validation for the Analysis of Trace Elements in Illicit Heroin

摘要

The analysis of the trace elements present in the street doses of heroin has currently been undertaken with a dual aim: to estimate the elemental compositions and to cluster the case samples. Inductively coupled plasma-mass spectrometry was optimized to quantify 18 trace elements simultaneously. The method presented high repeatability and reproducibility for the target elements. The linear concentration ranges achieved linearity with r ~2 > 0.9975. The limits of detection (LOD) were sufficiently low for almost all the elements except for Ca (LOD = 100 ppb). The limit of quantification (LOQ) for each element was also found acceptable. All target elements show mean recoveries between 92%-108%. Other major findings of this study including intra-sample (RSD < 5%) and inter-sample (RSD < 14%) precisions, sample weight test (≥30 mg), dissolution vessels, and sample filtration are also reported. The capability of the optimized method was assessed by using forty case samples. With their elemental compositions statistical classification of these case samples is also discussed herein.