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建立并优化了利用气相色谱-质谱(Gas chromatography-mass spectrometry,GC-MS)检测酰基高丝氨酸内酯(Acyl-homoserine lactones,AHLs)的分析方法。通过优化升温程序,采用选择离子检测(m/z 143),可同时检测7种AHLs(C4、C6、C7、C8、C10、C12和C14),检出限分别为1.50、2.00、1.50、2.00、2.00、2.50和2.50μg l-1,在2.0 mg l-1浓度范围内均呈线性关系(R2>0.997)。加标回收率实验表明,采用乙酸乙酯萃取,水中7种AHLs的回收率均在54%~97%之间;不同比例的土水体系中,砖红壤和黄棕壤提取液中AHLs的回收率均在56%~108%之间。不同介质中AHLs回收率与其Log P值(P:AHLs在正丁醇和水溶液中的分配比)及水溶解度对数均显著相关,表明采用乙酸乙酯萃取水和土壤提取液中的AHLs时,回收率主要与AHLs的Log P值和水溶解度有关。采用该方法对土壤提取液中AHLs进行测定发现砖红壤和黄棕壤提取液中7种AHLs的浓度分别为3.8~8.7μg l-1和4.2~9.8μg l-1。因此,不仅对于水溶液,土壤提取液等复杂介质中的AHLs也可以采用乙酸乙酯萃取后GC-MS进行分析测定。
The analytical method for the determination of Acyl-homoserine lactones (AHLs) by gas chromatography-mass spectrometry (GC-MS) was established and optimized. Seven kinds of AHLs (C4, C6, C7, C8, C10, C12 and C14) can be detected simultaneously by using selective ion detection (m / z 143) with the detection limits of 1.50, 2.00, 1.50, 2.00 , 2.00, 2.50 and 2.50 μg l-1, respectively, showed a linear relationship (R2> 0.997) at 2.0 mg l-1 concentration. Spiked recoveries experiments showed that the recovery of seven AHLs in water was between 54% ~ 97% with ethyl acetate extraction. AHLs recovery of brick red soil and yellow brown soil in different proportions of soil water system The rates are between 56% and 108%. The recoveries of AHLs in different media were significantly correlated with their Log P values (P: AHLs partition ratio in n-butanol and aqueous solution) and water solubility logarithm, indicating that the recovery of AHLs from water and soil extracts using ethyl acetate The rates are mainly related to Log P values and water solubility of AHLs. Using this method, the AHLs in soil extracts were found to be 3.8 ~ 8.7μg l-1 and 4.2 ~ 9.8μg l-1 in brick red soil and yellow brown soil extract, respectively. Therefore, not only AHLs in complex media such as aqueous solution and soil extract can also be analyzed by GC-MS after ethyl acetate extraction.