New Methods Of Determination Of Some Hazardous Substances In Food By GC / MS And Hpce

In recent years the chromatography develops rapidly, and it has been used widely. In thepaper, the application of chromatography in food safety analysis has been reviewed, includingapplication of GC/MS and HPCE in food analysis.In chapter 2, a novel method of high performance capillary electrophoresis (HPCE) hasbeen established for the separation of melamine in milk and milk powder. Trichloroacetic acidsolution was used to precipitate proteins and to dissociate the melamine from the samplematrix. In order to dissociate the proteins clean and simply, the sample was heated to boil,then cooled naturally. The average recoveries ranged from 83.2% to 97.5% in the spikedrange of the determination of melamine in milk and milk powder. The limit of quantification(LOQs) of milk and milk powder was 1.0 mg/kg, and the relative standard deviations werebetween 2.1% and 3.9% (n = 5). The sensitivity of the method is similar to thehigh-performance liquid chromatography, and the sample pre-treatment is more simple,specific, reproducible, economic, environment. So it can be used for a large number ofsamples of milk and milk powder's melamine rapid detection.In chapter 3, a new method of the determination of difenoconazole in Vegetable byGC-MS/MS was developed. The difenoconazole in sample was extracted with acetonitrile.The extract was purified and concentrated with solid phase extraction column, then detectedby GC-MS/MS in the multiple reaction monitoring mode. The average recoveries rangedfrom78.82% to 94.64%,The limit of quantification (LOQs) was 10μg/kg, The calibrationcurve was linear between 0.01 mg/L and 0.25 mg/L(10μg/kg - 250μg/kg), and thecorrelation coefficient was more than 0.99.In chapter 4, a novel method of simultaneous differmination of amitraz and chlordimeformin honey by GC-MS/MS was investigated. The amitraz and chlordimeform in sample wereextracted with mixture of acetone and n-hexane, the extract was purified and concentrated,then detected by GC-MS/MS. The calibration curve was linear of amitraz,chlordimeform and2,4 - xylidine between 0.01 mg/L and 0.2 mg/L(10μg/kg - 200μg/kg), and the correlationcoefficient was more than 0.990. The average recovery was ranged from 76.83%-91.35%.