Objective To establish a method for rapid determination of 58 kinds of pesticide residues in animal derived foods by QuEChERS-gas chromatography-tandem mass spectrometry (GC-MS/MS). Methods After dissolving the oil and fat in n-hexane, the sample was subjected to ultrasonic extraction with a saturated acetonitrile solution (containing 1% glacial acetic acid). The extract was purified with anhydrous magnesium sulfate, octadecyl bonded silica gel (C18), and N-propylethylenediamine (PSA), and then nitrogen was blown to near dryness in a water bath. An internal standard was added and dissolved in ethyl acetate. GC-MS/MS was used for determination, and the blank matrix matching standard curve internal standard method was used for quantification. Results The linear relationship between 58 kinds of pesticides was good within the mass concentration range of 0.005-0.500 mg/L, with correlation coefficients (r2) greater than 0.9945. The limits of detection and limits of quantification were 0.001-0.005 mg/kg and 0.002-0.015 mg/kg, respectively. The average recovery rates of pork, chicken, fish, eggs and milk matrices at 3 different spiked levels ranged from 71.8% to 117.4%, with relative standard deviations of 0.7% to 8.7% (n=4). Conclusion This method has high sensitivity and good accuracy, and is suitable for simultaneous determination of 58 kinds of pesticide residues in animal derived foods.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |