Determination of 10 Plant Growth Regulators in Bean Sprouts by Sequential Cleaning-Gas Chromatography-Mass Spectrometry / 分析化学

ABSTRACT

A sequential clean-up method was developed for the quantification of 10 plant growth regulators in bean sprout by the gas chromatography / mass spectrometry (GC / MS). The analytes were firstly extracted by the acided acetonitrile. Extraction was concentrated and re-dissovled by methanol. Then, it was divided to two aliquots. One of that was analyzed for 2,4-D-butyl ester and 2,4-D-ethyl ester after the purification by QuECHERS cartridge. Another one was treated by MCS solid phase extraction column including diverse eluting steps. After eluting by 5 mL methanol, composition 1 was obtain, concentrated, and methyl esterified by 10% boron trifluoride methanol solution. The treated extract was used for the determination of 4-chlorophenoxy acetic acid, β-naphthyl acetic acid, 2,4-dichlorophenoxy acetic acid, indole acetic acid and indole butyric acid. Composition 2 collected by eluting with 5 mL 5% amonium methanol was used for the determination of paclobutrazol, Kinetin, 6-Benzylaminopurine. The clean-up procedures are designed according to different chemistry properties of these plant growth regulators. The results showed that after spiking of 0. 01-0. 1 mg / kg selected plant growth regulators, average recovery ranged from 70. 0% to 93. 2%and relative standard deviation were 5. 2% -12. 3% . Limit of quantification (LOQ S / N≥10) and limit of detection (LOD S / N≥3) were 0. 01-0. 025 mg / kg and 0. 003-0. 008 mg / kg respectively. The developed purification method is easy, fast and accurate, and can be applied to routine test of plant growth regulators in bean sprout.