柱前衍生/高效液相色谱法测定果蔬中仲丁胺残留

建立了高效液相色谱(HPLC)测定仲丁胺的分析方法。试样采用全自动凯氏定氮仪蒸馏,蒸馏液经碱中和,以9-氯甲酸芴甲酯(FMOC)为衍生剂在碱性条件下衍生,衍生产物经C18柱分离,紫外检测器(265nm)检测。实验考察了衍生剂浓度、硼酸盐缓冲溶液的p H值、反应温度与时间等因素对衍生反应的影响,结果表明,最优的衍生剂浓度为0.50 g/L,缓冲溶液p H值为8.0,反应温度为室温,反应时间为15 min。在此条件下,仲丁胺在0.001~1.000 mg/L浓度范围内与其响应信号呈良好的线性关系,相关系数为0.999 8,加标回收率为82.4%~95.2%,相对标准偏差为1.3%~6.8%,方法检出限为0.1μg/kg,定量下限为0.5μg/kg。该方法快速、简便、安全、灵敏度高、重现性好,可用于果蔬中仲丁胺残留的测定。

Determination of 2-Aminobutane in Vegetables and Fruits by High Performance Liquid Chromatography Coupled with Pre-column Derivatization

A high performance liquid chromatographic method with pre-column derivatization was developed for the determination of 2-aminobutane in vegetables and fruits.The sample was distilled with kjeldahl apparatus.The distillate was neutralized with NaOH solution before derivatization with 9-fluorenylemethyl chloroformate (FMOC) as derivatization agent under alkaline condition.The sample was separated on a C1s analytical column and detected by HPLC with a UV detector at a wavelength of 265 nm.Systematic investigation was carried out on the dependence of the dcrivatization conditions such as concentration of derivatization,pH value of borate buffer solution,reaction temperature and time etc.The optimized conditions were as follows:concentration of derivatization:0.50 g/L,pH value of borate buffer:8.0,reaction temperature:room temperature,and reaction time:10 min.Under the optimal conditions,a linear relationship was achieved between the peak area and the concentration of 2-aminobutane in the range of 0.001-1.000 mg/L,with a correlation coefficient of 0.999 8.The recoveries at three spiked levels were in the range of 82.4％-95.2％ with relative standard deviations (RSDs) of 1.3％-6.8％.The limit of detection (LOD) was 0.1 μg/kg,and the limit of quantitation (LOQ) was 0.5 μg/kg.With the advantages of rapidness,simplicity,safety,high sensitivity and reproducibility,this method is suitble for the determination of 2-aminobutane in vegetables and fruits.