食品及空心胶囊中铬测定的前处理方法的研究

Pretreatment method for determination of chromium in foods and hollow capsule

目的探究不同前处理方法对食品及明胶空心胶囊中铬测定结果的影响。方法采用湿消解法、微波消解法、干灰化法进行样品前处理,石墨炉原子吸收法进行测定。结果 3种前处理方法对标准物质的检测结果除干灰化法奶粉的检测结果略低外,均在标准值规定的范围内;3种前处理方法对8种样品的检测结果的统计学分析显示,湿消解法与微波消解法之间差异无统计学意义(P>0.05),而干灰化法与其他两种消解方法之间差异有统计学意义(P<0.05)。结论本试验所用的3种前处理方法均可用于食品中铬的检测;湿消解法的实用性较强,对于任何基质的样品都可以进行很好的消解;干灰化法的空白值低,方法操作简单,但检测结果偏低;微波消解法样品消解时间短、空白值较低、试剂用量少、重现性好。

Objective To study the effects of different pretreatment methods for determination of chromium in food and gelatin hollow capsule. Methods Sample pretreatment was conducted by wet digestion,microwave digestion and dry ashing. The content of chromium in food and gelatin capsule was determined by graphite furnace atomic absorption spectrometry. Results The results of the three methods for 4 kinds of standard material were in the range of the standard value. Statistical results of the three methods for 8 samples showed that there was no significant difference between wet digestion and microwave digestion（ P 0. 05）,but there was significant difference between the dry ashing and the other two digestion methods（ P 0. 05）. Conclusion The three methods could be used for the determination of chromium in foods. Wet digestion was suitable for any food matrix. Dry ashing had the advantages of simple operation and low blank value,but test result was lower than the other two methods. Microwave digestion had the advantages of fast,low blank value,less reagent consumption and good repeatability.