不同消解方式对电感耦合等离子体质谱法测定灵芝中锗的影响

Effect of different digestion methods on determination of germanium in Ganoderma lucidum by inductively coupled plasma mass spectrometry

目的为电感耦合等离子体质谱法测定灵芝中锗建立合适的前处理方法。方法采用微波消解、高压罐消解、传统湿法消解和干法消解对选取的灵芝样品进行前处理。使用电感耦合等离子体质谱仪测定锗的含量,同时测定回收率和精密度,并对检测结果进行统计分析。结果4种方式消解后检测结果经单因素方差分析多重比较(LSD法)可知微波消解与高压消解罐消解的结果差异无统计学意义(P>0.05),而传统湿法消解、干法消解与高压罐消解、微波消解的结果差异有统计学意义(P<0.05)。微波消解和高压罐消解的测定结果回收率为79.78%~100.90%,精密度分别为12.99%、1.85%,检出限分别为0.0025 mg/kg、0.0016 mg/kg。结论灵芝消解时需加入少量氢氟酸。消解完成得到的溶液澄清但有少量不可溶残渣时应在进样前经0.22μm聚四氟乙烯微孔滤膜过滤。微波消解和高压罐消解方法更适用于灵芝的消解。

Objective To establish a suitable pretreatment method for the determination of germanium in Ganoderma lucidum by inductively coupled plasma mass spectrometry(ICP-MS/MS).Methods The samples of Ganoderma lucidum were pretreated by microwave digestion,autoclave digestion,traditional wet digestion and dry digestion.The content of germanium in Ganoderma lucidum samples was determined by ICP-MS/MS,the recovery and precision were determined,and the detection results were statistically analyzed.Results After digestion by four different methods,the results of one-way ANOVA multiple comparison(LSD method)showed that the difference on the results of microwave digestion and autoclave digestion were not statistically significant(P>0.05),while the results of traditional wet digestion and dry digestion were different from those of autoclave digestion and microwave digestion,with the differences statistically significant(P<0.05).The recovery of microwave digestion and autoclave digestion was within 79.78%-100.90%,the precision was respectively 12.99%and 1.85%,and the detection limits were respectively 0.0025 mg/kg and 0.0016 mg/kg.Conclusion A small amount of hydrofluoric acid should be added in digestion.The clear solution obtained after digestion should be filtered by 0.22μm polytetrafluoroethylene microporous membrane before injection if there is a small amount of insoluble residue.Microwave digestion and autoclave digestion are suitable for the digestion of Ganoderma lucidum.