Mierzwa S, Witek S
J Chromatogr. 1977 Jun 1;136(1):105-11. doi: 10.1016/s0021-9673(00)82999-4.
A gas-liquid chromatographic method with electron-capture detection was developed for the determination of residues of 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylpenoxyacetic acid (MCPA) in water as their 2,2,2-trichloroethyl esters, and the sensitivity was compared with that for 2-chloro- and 2,2,2-trifluoroethyl esters. The residue is isolated by sorption of the phenoxy acid on Amberlite XAD-4, eluted with benzene and then esterified with 20% (v/v) 2,2,2-trichloroethanol in trifluoroacetic anhydride in the presence of sulphuric acid. The recoveries at the 0.4 ppb level are 92.1 +/- 3.4% (2,4-D) and 87.8 +/- 2.1% (MCPA) and the detection limits for a 1-1 sample of water are 0.096 ppb (2,4-D) and 0.06 ppb (MCPA).
建立了一种带电子捕获检测的气液色谱法，用于测定水中2,4-二氯苯氧乙酸（2,4-D）和4-氯-2-甲基苯氧乙酸（MCPA）的残留量，以其2,2,2-三氯乙酯形式存在，并将该方法的灵敏度与2-氯乙酯和2,2,2-三氟乙酯的灵敏度进行了比较。通过将苯氧酸吸附在Amberlite XAD-4上分离残留量，用苯洗脱，然后在硫酸存在下，于三氟乙酸酐中用20%（v/v）2,2,2-三氯乙醇进行酯化。0.4 ppb水平下的回收率分别为92.1±3.4%（2,4-D）和87.8±2.1%（MCPA），对于1升水样的检测限分别为0.096 ppb（2,4-D）和0.06 ppb（MCPA）。
