GB/T 5009.113-2003 Determination of insecticide residues in rice

This standard specifies the determination of the content of cyclopentane in rice by gas chromatography. This standard is applicable to the determination of the residual amount of cyclopentane in rice. The detection limit of this standard is 4.7×10 GB/T 5009.113-2003 Determination of the residual amount of cyclopentane in rice GB/T5009.113-2003 Standard download decompression password: www.bzxz.net

128 67.040
National Standard of the People's Republic of China
GB/T 5009.113---2003
Replaced GE/T_4929.7..-1994
Determination of thiocyclan residues in rice
Determination of thiocyclan residues in ricePublished on August 11, 2003
Ministry of Health of the People's Republic of China
National Standard Management Committee of China
Implemented on January 1, 2004
CB/T 5009.113—2003
This standard replaces B/T14929.7—1994. Determination of the residue of insect ring in rice. 3. Compared with G/T11929.7—1994, the main modifications of this standard are as follows: the Chinese name of the standard is changed to Determination of the residue of insect ring in rice, and the structure of the original standard is modified in GB/T2C001.4—2001 Rules for the preparation of standards Part 4: Chemical analysis method.
This standard is proposed and managed by the Ministry of Health of the People's Republic of China. The drafting unit of this standard is: the Chinese Academy of Medical Sciences. The original standard was first issued in 1994. This is the second revision. This standard specifies the content of insecticide residues in rice by the gas spectrum method. The residual content of insecticide residues in rice detected by this standard is 4.7X202. 5009.113-2003
Under acidic conditions, the insecticide is extracted with formazan and purified by decomposition and then transferred to alcohol. It is quantified by gas phase catalysis with an electron capture detector and compared with the standard. 3.1 For alcohol, there should be no staining peak under the conditions specified in this test, otherwise it will be evaporated to the following format: 3.2 First-class boiling: Take a certain amount of second-class alkanes - add water for a period of 1% or 6 times (the maximum number of layers must be separated and separated, and dihydrogen 2 is released. Avoid bringing water into the mixture to avoid the danger of explosion during concentrated acid grinding!), add 5 volumes of concentrated sulfuric acid until the color does not change. Then use 52% sodium hydroxide to dissolve and wash to medium, then wash with water 2 or 3 times, dry it with anhydrous water, pass through the whole glass to keep the heavy heat storage, and then remove the impurities. 3.3 Sodium hydrogen carbonate.
3.4 ​​Sodium carbonate, 15 minutes 2h, use. 3.5 Filter aid: celite545.
3.6 5ul/1.
3.8 CR\I. Sodium hydroxide hook penetration liquid.
3.910/acid sugar.
3.10 Re-phase, 5% OV-225Chromosorb (AW-MS) 3.11 Tea quality standard: Use methanol to prepare 2,Dg,ml. of tea quality liquid. 4.1 Gas chromatograph (with electron storage device: 1.2 Small electric powder sifter.
4.3 Serial evaporator.
4.4 Electric drug solution.
4.5 69mL separatory funnel
5 Analysis steps
5.1 Take 40% of the rice powder and put it in a 250mL triangular bottle. Add 100L of formaldehyde and 5mol/1. After a slight vibration, pass a small amount of it4 through the filter. Collect the filtrate and transfer it to a 252 mesh bottom flask. Place it in a rotary evaporator in a water bath with equal mE.3mL of stone 5.2 Chemical reaction: Transfer the residue to a 65mL separatory funnel and separate it with 20mL of distilled water and diaminomethane, respectively. Wash the flask twice, and then use the test paper to check the water content. The pH should be about 1.65
GB/T5009.113--2GI3
Shake the funnel for 30 minutes, let it stand for stratification, and discard the lower dichloromethane layer: 20ml. Shake the dichloromethane 7-8 times, and discard the dichloromethane. Add a small amount of iodine 7-8 to the funnel, and gently shake the water layer with 30ml dichloromethane 3 times. Take the dichloromethane and pass it through a slide with anhydrous sulfuric acid. Add 250mL of 10.2ml of 10-indole and 5ml of methanol, and use a rotary evaporator to pulsate in a water bath to about 7.0%, and the concentrated solution is added to a stoppered scale test tube. The content is adjusted to 5mL--10m l, take 1.0 into the chromatograph, quantify by external standard method, 5.3 Gas chromatograph strip
5.3.1 Chromatography: m2m entrapment:
Fill with a mass phase coated with %OV-22iChraunanrbW (4W·TMCs). 5.3.2 Thermoelectric
Record, 190
Vaporation rate: 2000:
5.3.3 Gas flow rate: Gas (high) flow rate 30mL/mi. 5.3.4 Other conditions
Instrument sensitivity: 1:
Filter. 9.4cm/min
Gas: commercially pure
5.4 Settling
Adjust the instrument according to the above conditions, and inject the sample or standard solution with a micro syringe after settling: the retention time is used as the qualitative Indicators. The standard flow of the killing ring is reduced by methanol with a series of 4C.8, 1.2.1, and 2.0mL, respectively, and injected into the chromatographic collection center, and the working curve is plotted with the ring volume as the horizontal axis and the height as the horizontal axis. According to the peak quantity of the sample, the result is calculated as follows:
—ring volume, g/kg (m/R)
R-.~Tear the peak height value of the sample, check the ring volume after the standard, the unit is nanogram (gt7--tube volume in ml).>
A injection volume, the unit is L)
——sample mass, the unit is g):
8-, the measured value is equivalent to half of the sample, and the whole calculation is multiplied by 2. The engineer's result shall be retained to two significant figures.
7 Precision
The absolute value of the results of two independent tests obtained under the condition of repeated efficacy shall not exceed the arithmetic mean. 8 Others
The color chart of the insecticide ring of rice series and standard products is shown in Figure 1, 66
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1--Shachu
Yiweiquan.
GB/T 5009.113--2003
B) Sample color description
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