婴幼儿配方乳分中锰的测定能力验证3种前处理方法结果比较

Comparison of three pretreatment methods for determination of manganese in infant formula milk powder

目的用ICP-AES测定婴幼儿配方乳粉中锰的含量,比较3种不同前处理方法对结果的影响。方法依据GB 5009.268-2016第二法电感耦合等离子发射光谱法,采用微波消解、湿消解和干灰化3种前处理方法,对不同样品进行精密度和准确度实验。结果 17-Y341微波消解、湿消解、干灰化法结果分别为:224、202、207μg/100g;17-G283微波消解、湿消解、干灰化法结果分别为242、204、211μg/100g;婴幼儿配方乳粉标准样品中锰的微波消解、湿消解和干灰化法结果分别为:72.8 g、64.2、67.1μg/100 g,均在证书(79.66±22.84)μg/100g范围内,回收率RSD分别为2.2%、3.0%、2.8%。结论通过比较,微波消解法更适用于奶粉类基质的测定,具有称样量少、前处理步骤少的优势。

Objective To find the best pretreatment method for the milk powder matrix samples and to compare the effects of three different pretreatment methods on the results.Methods According to the second method of GB 5009.268-2016,Inductively Coupled Plasma Emission Spectrometry,the precision and recovery of three pretreatment methods were compared by microwave digestion,wet digestion and dry ashing.Results The results of 17-Y341 microwave digestion,wet digestion and dry ashing were： 224,202,207 μg/100 g respectively; The results of microwave digestion,wet digestion and dry ashing were 242,204,211 μg/100 g respectively; The results of microwave digestion,wet digestion and dry ashing of manganese in standard samples of infant formula milk powder were 72.8,64.2,67.1 μg/100 g. In the certificate range of 79.66±22.84 μg/100 g,the recovery rate of RSD was 2.2%,3.0% and 2.8% respectively.Conclusion By comparison,microwave digestion is more suitable for the determination of milk powder matrix and has the advantages of less sample size and less pretreatment steps.