赣南脐橙中苯乙烯、乙苯迁移量的测定

Determination of Migration of Styrene and Ethylbenzene in Gannan Navel Orange

试验采用高效液相色谱法,旨在测定赣南脐橙中苯乙烯和乙苯迁移量。样品经甲醇提取,选取色谱柱Agilent ZOBBAX SB-C18进行分离,在流动相乙腈-水条件下进行等浓度洗脱,流速1.0 mL/min,在254 nm波长下检测,外标法定量,实现赣南脐橙中苯乙烯、乙苯迁移量的定性定量分析。结果表明,该方法分析时间适中,苯乙烯和乙苯在1~100μg/mL质量浓度范围内线性关系良好,最低定量限苯乙烯0.6 mg/kg、乙苯2.0 mg/kg,在添加水平均为5.0,15.0和50.0 mg/kg的条件下,苯乙烯和乙苯的加标回收率在97.2%~107.1%之间,相对标准偏差在0.06%~0.78%之间(n=6)。利用该方法对用苯乙烯、乙苯浸泡后晾干的泡沫箱中放置赣南脐橙密封后分别置于4和22℃环境下1,2,3,7和15 d取样分析检测,均检出苯乙烯、乙苯。试验方法具有回收率高、重现性好、灵敏度高等特点,可适用于赣南脐橙中苯乙烯和乙苯迁移量的定性定量分析。

A high performance liquid chromatography(HPLC)method for the synchronous determination of styrene and ethylbenzene in Gannan navel orange was established.The sample was extracted by methanol and separated on an Agilent(ZORBAX SB-C18)chromatographic column.The HPLC analysis was performed by using a gradient solvent system(acetonitrile-water)asmobile phase.The flow rate of moving phase was 1.0 mL/min and diode array detector was used at the wavelength of 254 nm.Quantitative analysis of styrene and ethylbenzene in Gannan navel orange was conducted by external standard method.The results showed that the analytical time of this method was moderate.The styrene and ethylbenzene could be separated completely in sample,and the linearity was good.The detection limit was 0.6 mg/kg for styrene and 2.0 mg/kg for ethylbenzene.The average recovery was 97.0%-107.1%,and the relative standard deviation(SRSD)was 0.06%-0.78%(n=6).This method was used to analyze the samples of Gannan navel orange placed in the foam box soaked with styrene and ethylbenzene and sealed at 4 and 22℃for 1,2,3,7 and 15 d,respectively.The results showed this HPLC method met the requirement of simultaneous detection of styrene and ethylbenzene in Gannan navel orange.The method was simple in operation,high in precision and good in repeatability.