This standard specifies the determination method of oxadiazon residues in rice and peanut kernels. This standard is applicable to the determination of oxadiazon residues in rice and peanut kernels. The detection limit of this method is 0.001ng. The linear range is 0.01μg/mL to 0.1μg/mL. GB/T 5009.180-2003 Determination of oxadiazon residues in rice and peanut kernels GB/T5009.180-2003 Standard download decompression password: www.bzxz.net

ICS67.040
National Standard of the People's Republic of China
GB/T5009.180--2003
Determination of oxadiazon residues in cereals and peanuts2003-08-11 Issued
Ministry of Health of the People's Republic of China
Standardization Administration of the People's Republic of China
2004-01-01 Implementation
This standard is proposed and managed by the Ministry of Health of the People's Republic of China. The responsible drafting unit of this standard: Jilin Provincial Health and Epidemic Prevention Station. The participating drafting units of this standard: Changchun Erdao District Health and Epidemic Prevention Station. The main drafters of this standard: Fang Chiguang, Li Qing, Jiang Fenghua, Jin Chenglu, Qiao Qigang. GB/T5009.180—2003
GB/T5009.180—2003
Oxadiazon, also known as Nongsita and Oxadiazon, is a selective pre- and post-emergence herbicide and a low-toxic herbicide. The drug has been registered for use in rice and peanut kernels in my country. my country stipulates that the residue of oxadiazon in rice is ≤0.05mg/kg, and the residue in peanuts is ≤0.1mg/kg. This standard provides a supporting method for detecting the residue of oxadiazon in rice and peanut kernels. 464
1 Scope
Determination of Oxadiazon Residues in Rice and Peanut Kernels This standard specifies the method for determining the residue of oxadiazon in rice and peanut kernels. This standard is applicable to the determination of the residue of oxadiazon in rice and peanut kernels. The detection limit of this method is 0.001ng.
Linear range: 0.01uμg/mL~0.1μg/mL. 2 Principle
GB/T5009.180—2003
The oxadiazon in the sample is extracted with an organic solvent, purified by a Florisil pre-treated column, and determined by a gas chromatograph with an electron capture detector, and quantified by the external standard method.
3 Reagents
3.1 Acetone.
3.2 Ether.
3.3 N-hexane.
3.4 ​​Anhydrous sodium sulfate: calcine at 650℃ for 4h and store in a sealed container for later use. 3.5 Oxadiazon, purity ≥98%. 3.6 Standard stock solution: weigh 0.1000g of oxadiazon, place in a 100mL volumetric flask, dilute to the mark with n-hexane, and prepare a stock solution with a concentration of 1.000mg/mL.
3.7 Standard working solution: Dilute the standard stock solution (3.6) 100 times to a concentration of 10μg/mL. 3.8 Pretreatment column: PT-Florisil adsorbent (commercially available). The Florisil adsorbent column was eluted with 4mL of n-hexane, 4mL of n-hexane-ether (2+1), and 2mL of n-hexane in sequence. 4 Instruments and equipment
4.1 Gas chromatograph: with an electron acquisition detector (ECD). 4.2 Small pulverizer.
4.3 Ultrasonic cleaner.
4.4 KD concentrator.
5 Analysis steps
5.1 Sample preparation
Weigh 5.00g of the crushed sample into a 100mL beaker, add 10mL of acetone, extract in an ultrasonic cleaner for 10min, transfer the supernatant into a 25mL volumetric flask, repeat the extraction once, dilute to 25mL with acetone, take 1mL of the extract, blow dry with nitrogen, and dissolve in 2mL of n-hexane.
5.2 Purification
Transfer the extract (5.1) into the treated Florisil adsorption column, elute with 10mL of n-hexane, elute with 5mL of n-hexane-ethyl ether (2+1), collect the eluate in a KD concentrator, blow dry with nitrogen, and dilute to 1.0mL with n-hexane for later use. 5.3 Gas chromatography reference conditions
5.3.1 Chromatographic column: 0V-17 cross-linked capillary column (30m×0.53mm×0.25μm). 465
GB/T5009.180-2003
5.3.2 Temperature: Column temperature 185℃, vaporization chamber and detector temperature 230℃. 5.3.3 Carrier gas: Nitrogen (purity 99.999%), split ratio 30:1. Tail blowing 50ml/min. 5.4 Determination
Prepare the standard working solution into a standard series of 0.000, 0.005, 0.010.0.020.0.040.0.060, 0.080, 0.100g/mL, take 1μL of each and inject it into the gas chromatograph, and record the peak area (or peak height). Take 1 μL of the purified solution (5.2) and inject it into the gas chromatograph, record the peak area (or peak height), and calculate the content of oxadiazon in the sample from the standard curve.
6 Result calculation
The content of oxadiazon in the sample is calculated according to formula (1). X=XiXVX1000
mx1000wwW.bzxz.Net
Wherein:
X---the content of oxadiazon in food, in milligrams per kilogram (mg/kg); X--the content of oxadiazon calculated from the standard curve, in micrograms per milliliter (μug/mL); m
-the mass of the sample, in grams (g);
V--the volume of the sample extract, in milliliters (mL). Result expression: The calculation result is expressed to two decimal places. Precision
The absolute difference between two independent determination results obtained under repeatability conditions shall not exceed 10% of the arithmetic mean. 8 Gas chromatography reference chart
Conditions Chromatographic column: 0V-17 cross-linked capillary column (30m×0.53mm×0.25μm). Temperature: Column temperature 185℃, vaporizer and detector temperature 230℃. Carrier gas: nitrogen (purity 99.999%), split ratio 30:1, tail gas 50mL/min. 91
Figure 1 Chromatographic reference chart of oxadiazon standard Sample
Sample spiked (peanut) chromatogram
(1)
Figure 3 Chromatogram of blank sample (peanut)
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.