您所在的位置: 首頁> 檢測知識> 食品安全問題> 有機磷類和氨基甲酸酯類農藥的快速檢測

食品安全問題

有機磷中毒表現、治療原則
方法注解

有機磷類和氨基甲酸酯類農藥的快速檢測
(農藥速測卡使用說明) 方法編號:CDC-1011

1 適用范圍: 本方法適用于蔬菜、水果、相應食物、水及中毒殘留物中有機磷類和氨基 甲酸酯類農藥及鼠藥的快速檢測。本方法引自國家標準快速檢測方法GB/T5009.199-2003。

2 檢測原理:
有機磷或氨基甲酸脂類農藥對膽堿酯酶有抑制作用, 可抑制膽堿酯酶試劑在特定條件下的顯色狀態,通過目視或儀器來判斷樣 品中是否含有有機磷類或氨基甲酸酯類農藥的存在。

3 檢測試材
3.1包被了膽堿酯酶等試劑的農藥速測卡;
3.2農藥提?。ń幔┮?;
3.3蔬菜整體測定法時需要0.1g感應量的天平;
3.4有條件時,可選用具有加熱、定時程控程序的農藥殘毒速測儀。

4 蔬菜、水果中農藥殘留量的檢測、結果判斷與注意事項
4.1 表面測定法(粗篩法): 擦去蔬菜表面泥土,滴2~3滴浸提液在蔬菜表面,用另一片蔬菜在滴液處輕輕摩擦。取一片速測卡,將蔬菜上的液滴滴在白色藥片上。放置10min進行預反應,將速測卡對折(紅色藥片與白色藥片疊合)后,用手捏3min時,打開與空白對照實驗卡比較,白色藥片不變色或略有淺藍色均為陽性結果。白色藥片變為天藍色或與空白對照卡相同為陰性結果。有條件時,將紙片插入“農藥殘留速測儀”自動恒溫、定時檢測。
4.2 整體測定法: 選取有代表性的蔬菜樣品,擦去表面泥土,剪成1cm左右見方碎片,取5g放入帶蓋瓶中,加入10mL浸提液(樣品與浸提液的比例為1+2),震搖50次(有條件時,可將提取瓶放入超聲波提取器中震蕩30秒),靜置2min以上。取一片速測卡,在白色藥片上滴上2~3滴提取液,放置10min進行預反應,將速測卡對折(紅色藥片與白色藥片疊合)后,用手捏3min時,打開與空白對照實驗卡比較,白色藥片不變色或略有淺藍色均為陽性結果。白色藥片變為天藍色或與空白對照卡相同為陰性結果。有條件時,將紙片插入“農藥殘留速測儀”自動恒溫、定時觀察。
4.3注意事項:
4.3.1 目前國內外所使用的農藥殘留測定方法(紙片法和分光光度法)的檢驗原理基本相同,測定中的干擾物質也基本相同。蔥、蒜、蘿卜、芹菜、香菜、茭白、蘑菇及番茄汁液中含有對酶有影響的植物次生物質,容易產生假陽性。處理這類樣品時(包括含葉綠素較高的蔬菜),不要剪的太碎。測定番茄時,可將提取液放在茄蒂處浸泡2min,取浸泡液測定。測定韭菜或大蒜時,可整根或整粒放入容器中,加入提取液后振搖提取測定。
4.3.2 飲用水中的農藥檢測,可直接取2~3滴加到速測卡上進行操作。茶樹上茶葉中的農藥檢測,可按本方法測定,加工后的茶葉,參照“相應食物及中毒殘留物中農藥的檢測”。
4.3.3 檢測樣品的速測卡預反應放置的時間應與空白對照卡放置的時間盡量一致。紅色藥片與白色藥片疊合反應的時間控制在3min,打開觀察結果的時間應以1min內為準。
4.3.4 空白對照卡不變色的原因,一是有可能藥片表面提取液加的少、預反應后的藥片表面不夠濕潤;二是提取液(緩沖液)的酸堿度可能有問題(此時可用純凈水作對比確認);三是速測卡已過有效期。
4.3.5 在確定樣品為有機磷或氨基甲酸酯類農藥陽性結果時,應是重復多次檢測的結果,必要時將樣品送實驗室用氣相色譜儀或質譜儀進一步確定是哪種農藥、確切含量。

5 相應食物及中毒殘留物中農藥的檢測、結果判斷與注意事項:
5.1樣品處理與測定: 取樣品適量于容器中,加入2倍量的乙酸乙酯,充分震搖后靜置,取澄清液于蒸發皿中,在水浴上蒸干乙酸乙酯,取1mL磷酸鹽浸提液溶解蒸干后的殘渣,取殘渣溶液2~3滴于速測卡白色藥片上,放置10min進行預反應,將速測卡對折(紅色藥片與白色藥片疊合),用手捏3min,打開速測卡,與同時操作的空白對照速測卡(白色藥片上只加浸提液的速測卡)比較,白色藥片不變色為強陽性結果,略有淺藍色為弱陽性結果,天藍色或與空白對照卡相同,為陰性結果。
5.2 注意事項:
5.2.1 在確定樣品為有機磷或氨基甲酸酯類農藥陽性結果時,應是重復多次檢測的結果,對于中毒殘留物,必需將樣品送實驗室用氣相色譜儀或質譜儀進一步確定是哪種農藥、確切含量。
5.2.2 其他注意事項與蔬菜、水果中農藥殘留量的測定注意事項相同。

6 農藥速測卡的質量控制
6.1 按操作方法與注意事項進行,只加pH7.5磷酸鹽浸提液或純凈水的農藥 速測卡應變為藍色;0.3mg/kg的敵敵畏或敵百蟲溶液,可使農藥速測 卡呈陽性反應。

7. 產品儲藏與效期: 速測卡閉光常溫保存有效期為1年。冷藏可延長有效期。

Rapid Test for Organophosphate and Carbamate Pesticides
1 Scope of application: This method is suitable for organophosphorus and carbamate pesticide detection in vegetables, fruits, appropriate food, water and toxic residues. It is taken from fast national standard detection methods GB/T5009.199-2003.

2 Detection principles

3 test specimens
3.1 Rapid detection of pesticides card
3.2 Ethyl acetate
3.3 pH7.5 phosphate extraction (buffer) solution: 15.0g disodium hydrogen phosphate were taken [Na2HPO4 ? 12H2O] and 1.59g of potassium dihydrogen phosphate [KH2 PO4], with 500mL distilled water.
3.4 Balance
3.5 Rapid Test for pesticides designed "pesticide residues Tachometer" and ultrasonic extractor.

4 Fast tests of pesticide residues in vegetables and fruits. Judgment of the results and Notes.
4.1 Determination by the surface (coarse sieve method): vegetables, wipe the surface soil, drop 2 or 3 drops of extract in vegetable surface, with the other pieces of vegetables gently in the drip Department of friction. Take a quick test card, the vegetables on the liquid drops on the white pills. 10min placed pre-reaction, the Rapid Test Pack (red and white tablets pills superimposed), the Yong Shounie 3min, open the card compared with the control experiment; if the white tablets change into light blue or does not change color, then the results are positive. If the white tablet changes into blue or the same as the control card, then the result is negative. Conditionally, it will slip into "pesticide residues Tachometer" automatic thermostat, timing detection.
4.2 Determination by the whole: select representative samples of vegetables, wipe the surface of the soil, cut into 1cm square pieces around, take into Lid 5g bottle, add 10mL extract (extract of the sample and the ratio is 1 + 2), shake 50 times (conditional, can be extracted in the extractor bottle into the ultrasonic vibration for 30 seconds), stand more than 2min. Take a quick test card drops on the white pills on 2 to 3 drops of extract, pre-placement 10min reaction, the Rapid Test Pack (red and white tablets pills superimposed), the Yong Shounie 3min, open and empty control experiments card comparison, if the white tablets change into light blue or does not change color, then the results are positive. If the white tablet changes into blue or the same as the control card, then the result is negative. Conditionally, it will slip into "pesticide residues Tachometer" automatic thermostat, timing observation.
4.3 Note:
4.3.1 Using pesticide residue determination methods at home and abroad (disk diffusion method and spectrophotometry) are in the same test principle, determination of interfering substances are basically the same. Onion, garlic, radish, celery, parsley, water bamboo, mushrooms and tomato juice contains the enzyme affect plant secondary substances prone to false positives. When dealing with such samples (including those with high chlorophyll vegetables), do not cut in too broken. Determination of tomato, the eggplant can extract on the City Department soak 2min, get soaking solution was measured. Determination of chives or garlic, it can put the whole container, whole root, or by adding extract measured after the shaking extraction.
4.3.2 Detection of pesticides in drinking water can be directly added to take 2 to 3 drops of speed measurement card to operate. Tea on the detection of pesticides in tea, can be measured this way, processed tea, the light of "the corresponding residues in food and pesticide poisoning detection."
4.3.3 Detection Rapid Test samples placed in pre-reaction time should be placed with the control card as the same time. Red pills and white composite reaction time control pills in 3min, open observation time should be within 1min prevail.
4.3.4 control card does not change color because, first, tablets may increase the surface extract less, pre-reaction of the tablet surface moist enough; second extract (buffer) of pH may be a problem (when available pure water for comparison to confirm); Third, the operating environment in the air may contain pesticide residues.
4.3.5 In determining the sample of organic phosphorus or carbamate pesticides positive results, should be a repetition of the result of multiple detections, if necessary, the samples sent to the laboratory when using gas Se Pu Huo mass spectrometer instrument to further determine which Nongyao, the exact content.

5 The corresponding residues in food and pesticide poisoning, and the results determine and notes:
5.1 Sample handling and determination: to take the sample amount in the container, add 2 times the amount of ethyl acetate, after sufficient shaking standing, take mix with the pan in water bath on evaporation to dryness in ethyl acetate, to take 1mL phosphate extract after evaporation to dryness the residue dissolved, take 2 to 3 drops of solution residue on the white pills on a quick test card, placing 10min pre-reaction, the Rapid Test Pack (red and white tablets pills superimposed), hand pinching 3min, open the speed test card, and also control the operation speed test card (white tablet on an increase of only extract the Rapid Test) compared to white pills do not change color as the strong positive results, a slight light blue for the weak positive The results, sky blue or the same with the control card for the negative results.
5.2 Notes:
5.2.1 In determining the sample for the organophosphate or carbamate pesticides positive results, testing should be repeated many times the result of the poisoning, residues, essential to the sample sent to the laboratory using gas chromatography or mass spectrometry to further determine which pesticides, the exact content.
5.2.2 Other Considerations and vegetables and fruits in the determination of pesticide residues in the same note.

6 Pesticide quality control of Rapid Test:
6.1 How and attention issues, only add pH7.5 phosphate solution or pure water extraction of pesticides strain Rapid Test for the blue; 0.3mg/kg of dichlorvos, or trichlorfon solution, enables fast testing of pesticides card positive.

7. Product storage and Validity: Closed Light Rapid Test is valid for 1 year storage at room temperature. The storage can be extended by cold storage.

京ICP備05027438號     2000年創刊-北京中衛食品衛生科技公司
北京11选5选号 专业破解棋牌游戏试用 快乐8在哪里下载 好彩一走势图 广东快乐十分人工计划 河南福彩十一选五开奖结果 今天股票大盘是多少 四川快乐12准确率90的杀号 河南快三开奖视频 一辈子穷和炒股选哪个 福利彩3d