超级微波消解-ICP-MS/GFAAS法测定根茎类中药材中6种重金属元素含量的对比研究

Comparative Study on Determination of Six Heavy Metals in Rhizome Chinese Herbs by Ultrawave Digestion-ICP-MS/GFAAS

采用电感耦合等离子体质谱(ICP-MS)与石墨炉原子吸收光谱(GFAAS)结合超级微波消解法,测定根茎类中药材中铅(Pb)、镉(Cd)、铬(Cr)、镍(Ni)、铜(Cu)、钡(Ba)6种重金属元素的含量,并将所获取的结果进行对比分析研究。结果显示,在最优分析条件下,ICP-MS:各元素在质量浓度0~100μg/L范围内线性关系良好,相关系数为0.999 9~1.000 0,检出限不高于0.05 mg/kg,加标回收率在95.1%~101.3%,相对标准偏差为0.19%~3.16%;GFAAS:各元素在质量浓度0~50μg/L范围内线性关系良好,相关系数为0.9996~0.999 8,检出限不高于0.1 mg/kg,加标回收率在88.2%~97.5%,相对标准偏差为2.33%~7.27%;标准物质验证结果均在范围内。上述两种方法均能用于根茎类中药材中6种重金属元素含量的测定,但在精密度、检出限以及测定效率方面,ICP-MS法优于GFAAS法。

The contents of lead, cadmium, chromium, nickel, copper, barium in rhizome Chinese herbs were determined by inductively coupled plasma mass spectrometry(ICP-MS) and graphite furnace atomic absorption spectrometry(GFAAS) combined with ultrawave digestion, and the results were compared and analyzed. Under the optimal analysis conditions, the results of ICP-MS determination showed that the mass concentration of each element had good linear relationships in the range of 0~100 μg/L, the correlation coefficients were 0.999 9~1.000 0, the limits of detection were not higher than 0.05 mg/kg, the recovery rates were 95.1%~101.3%, and the relative standard deviations were 0.19%~3.16%. The results of GFAAS determination showed that the mass concentration of each element had good linear relationships in the range of 0~50 μg/L, the correlation coefficients were 0.999 6~0.999 8, the detection limits were not higher than 0.1 mg/kg, the recovery rates were 88.2%~97.5%, and the relative standard deviations were 2.33%~7.27%. The test results of the standard material were all within the range. Above two methods can be used to determine the contents of 6 heavy metals in rhizome Chinese herbs, but ICP-MS is better than GFAAS in terms of precision, detection limit data and determination efficiency.