Simultaneous Determination Of Residues Of Triazine Herbicides In Wheat By Performance Liquid Chromatography

simultaneous determination of 21 triazine herbicides in wheat was developed and evaluated.The 21 Triazine herbicides were: Metamitron, simetone, Hexazinoe, simazine, cyanazine, atraton, metribuzin, Desmethryn, atrazine, Secbumetone, Prometon, Ethiozin, Terbumeton, Ametryn, Propazine, Terbuthylazine, prometryn, Terbutryn, Trietazine, Dimethametryn and Sipropetryn. The analytical procedure involved in extraction with acetone,purification using a Florisil SPE (solid phase extraction) column (6ml,1000mg) and acetone-n-hexane (4:6,v/v). The elute fraction was blown to driness under the stream of nitrogen and the residue was dissolved in 1mL of acetonitrile, followed by separation and quantitative analysis by reverse phase HPLC using gradient elution for the baseline separation of the 21 Triazine herbicides and programmed ultraviolet wavelength shift detection in 35 min. The chromatographic condition, including column temperature, mobile phase, flow rate and ultraviolet detection wavelength were investigated. The optimized chromatographic conditions were: analytical column, SunFire^TM C₁₈, i.d. 5.0μm, 250×4.6mm; column temperature 35℃; mobile phase, acetonitrile-water; flow rate, 1mL/min; gradient elution from 0 min at 30% acetonitrile-water to 4 min at 35% acetonitrile-water, then to 15 min at 45%, from 15 min at 45% acetonitrile-water to 25 min at 55%, from 25 min at 55% acetonitrile-water sharply to 30 min at 65%, finally at 30 min changed into 75% acetonitrile until 35 min.We set the ultraviolet wavelength at 220 nm. The concentration ranges of 21 triazine herbicides were 0.05⁶.0mg/kg, and the correlation coefficients were >0.999. The average recoveries of 20 triazine herbicides in spiked wheat ranged from76.67% to 101.12%, and the relative standard deviations were between 0.5% and 11.1%.High performance Liquid chromatography-electrospray tandem mass spectrometry (HPLC-MS/MS) with positive mode was used for the optimization of the method, and the multi-reaction monitoring mode was employed for the confirm determination. The result was satisfactory.Another analytical method was developed for the simultaneous determination of 20 triazine herbicide residues in wheat using Ultra Performance LCTM(UPLC) for detection.Analytical time is decreased from 35 min to 5 min.The method was also applied to determine triazine herbicide residues in real wheat samples. It was concluded that this method was rapid,accurate, sensitive and repeatable for determining trace Triazine herbicides in wheat.