改进的QuEChERS法检测自制香梨果汁中石蜡方法的研究

Study on the improved QuEChERS method for the determination of paraffin in homemade fragrant pear juice

模拟工业石蜡对香梨果皮进行喷蜡处理,采用改进的QuEChERS方法检测香梨带皮榨汁的果汁中石蜡含量。样品经正己烷提取、PSA净化后进气相色谱/质谱的分析。选择C_(24)~C_(29)正构烷烃作为石蜡的代表物质,监测特征离子m/z 57.3、71.3、85.3、99.3,对石蜡定性定量分析。结果表明:石蜡在10~200μg/mL浓度范围内线性关系良好,相关系数为0.9994,相对标准偏差(RSD)为4.2%~13.1%(n=6)。方法的分析速度快、灵敏度高、定性定量准确可靠。

Pericarp of fragrant pear was sprayed with industrial paraffin wax.A modified QuEChERS method was used to detect the paraffin in the juice of the peel of fragrant pear.The samples were extracted by n-hexane and purified by PSA and then analyzed by gas chromatography/mass spectrometry.C_(24)~C_(29) n-alkanes were selected as the representative of paraffin,and the characteristic ions m/z 57.3,71.3,85.3 and 99.3 were monitored to make qualitative and quantitative analysis of paraffin.The results showed that the linear relationship was good in the range of 10~200μg/mL,the correlation coefficient was 0.9994,and the relative standard deviation(RSD)was 4.2%~13.1%(n=6).The method has the advantages of rapid analysis,high sensitivity,accurate and reliable qualitative and quantitative analysis.