【摘要】 建立了水稻植株、土壤、稻田水和稻米中甲氨基阿维菌素苯甲酸盐的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。样品用乙酸乙酯提取,经PCX固相萃取柱净化浓缩,收集的洗脱液再经乙酸乙酯萃取,上层萃取液由氮气吹至近干后,用甲醇定容。试样采用ACQUITY UPLC BEH C18色谱柱进行分离,以乙腈-醋酸铵为流动相,采用电喷雾正离子(ESI+)模式测定。甲氨基阿维菌素苯甲酸盐在1~200μg/L质量浓度范围内呈良好线性,相关系数不低于0.999。在0.1~50.0μg/kg加标水平下,水稻植株、土壤、稻田水和稻米的回收率为70%~110%,相对标准偏差(RSD)为0.3%~15.9%,定量下限(LOQ)为0.1μg/kg。该研究同时发现土壤和水稻植株样品对甲氨基阿维菌素苯甲酸盐表现出明显的基质抑制效应,稻田水样品则表现为基质增强效应。更多还原

【Abstract】 A method for the determination of emamectin benzoate by ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) was developed. The analytes were extracted using ethyl acetate,and cleaned with PCX column. The column eluents were extracted by ethyl acetate again. The extracts were blown to nearly dry by nitrogen,then dissolved in methanol. The sample solutions were separated on a BEH C 18 column (50 mm × 2. 1 mm,i. d. 1. 7 μm) using a gradient elution program of aqueous solution containing acetate and ammonium acetate. Qualitative and quantitative detections of the analytes were carried out under the multiple reaction monitoring (MRM) mode by MS with electrospray in positive ionization. The method had a good linear correlation (r≥0. 999) in the range of 1-200 μg/L. The recoveries of emamectin benzoate at spiked level of 0. 1-50. 0 μg/kg were in the range of 70%-110% with relative standard deviations (RSDs) of 0. 3%-15. 9%. The limit of quantization (LOQ) was 0. 1 μg/kg. There were significant matrix suppression effects in soil samples and rice straw samples,but matrix enhancement effect occured in water samples.更多还原