乳与乳制品中总砷测定的不同前处理方法比较

目的比较不同前处理方法的处理效果,选择适合乳与乳制品中总砷测定的前处理方法。方法分别采用湿法消解、干法灰化、微波消解对乳与乳制品样品进行前处理,利用氢化物原子荧光法测定总砷含量。结果 3种前处理方式的检测结果均满足方法学要求,湿法消解、干法灰化和微波消解的回收率分别为81.7%～86.5%,90.0%～94.4%和90.8%～95.6%,精密度分别为8.84%～9.80%,3.22%～4.37%和3.18%～4.82%;检出限分别为0.0042、0.00068、0.0028mg/kg;微波消解法处理的质控样品结果更接近于标准值。结论微波消解法操作简便、准确性好,适合乳制品企业批量产品检测。

Comparison of different pretreatment methods for determination of total arsenic in milk and dairy products

Objective To select a suitable pretreatment method for the determination of total arsenic in milk and dairy products by comparing the effects of different pretreatment methods. Methods The samples of milk and dairy products were pretreated by wet digestion, dry ashing and microwave digestion respectively, and the total arsenic content was determined by hydride generation atomic fluorescence spectrometry. Results The results of 3 pretreatment methods all met the requirements of methodology. The recoveries of wet digestion, dry ashing and microwave digestion were 81.7%?86.5%, 90.0%?94.4%, 90.8%?95.6%, and the precision were 8.84%?9.80%, 3.22%?4.37%, 3.18%?4.82%, respectively. The detection limits were 0.0042,0.00068 and 0.0028 mg/kg, respectively. The results of the quality control samples processed by the microwave digestion method were closer to the standard values. Conclusion The microwave digestion method is simple, accurate, and suitable for batch product testing of dairy companies.