Ochratoxin 赭麴毒素-定量-快篩試紙-甲醇萃取

• 原理
  側流體免疫層析法 (lateral flow immunochromatographic assay)，為快篩試劑的使用原理，藉由抗體抗原間的專一性與免疫親和力做檢測，被普遍應用在、病毒感染確認、妊娠測試、警局臨檢驗毒等方面。此方法多用於定性檢測，且顯色標定物上也有許多不同的種類，目前大多數的顯色方式是利用抗體吸附在膠體金（colloid gold）來呈色。
  
  Ochratoxin 赭麴毒素，依其在薄層層析法上螢光顏色的不同，通常分成A、B、C三種類型，其中以Ochratoxin A 毒性最強且產量最高，故一般赭麴毒素多以ochratoxin A為代表。赭麴毒素主要是真菌Aspergillus ochraceus、Penicillium verrucosum產生的二次(次級)代謝物。穀類(例如:米、玉米、麥類)、咖啡、香辛植物...等相關加工品或原料可能會受到赭麴毒素的汙染，目前在動物實驗上，已證實赭麴毒素 A 的暴露，會造成腎臟毒性，並引發腎臟癌
   
• 結果判讀
  極限:
  偵測極限(limit of detection, LOD)： 2 ppb 
  定量極限(limit of quantification, LOQ)：2 ppb
  偵測範圍:2–20 ppb(樣品超過20ppb需重新稀釋及測量)
• 樣品準備
  The sample to be tested should be collected according to accepted sampling techniques (see FGIS sampling protocol or contact your Neogen representative). Obtain a representative sample (minimum 100 g). Grind the sample so at least 95% of the ground material passes through a 20- mesh sieve (about the particle size of fine espresso — 600–850 microns). If not using Neogen’s prepared solution, prepare a 70% methanol solution by mixing 7 parts methanol with 3 parts distilled or deionized water for each sample.
   
• 樣品萃取
  1. Extract at a ratio of 1 part sample to 4 parts 70% methanol. For example, combine 10 g of ground sample with 40 mL of 70% methanol.
  2. Vigorously shake, using hand or mechanical means (250 rpm) for 3 minutes, or blend for 1 minute.
  3. Allow the sample to settle, then filter at least 4 mL with a filter syringe, or Whatman No. 1 filter paper. Alternatively, pipette sample into a 2.0 mL microcentrifuge tube and centrifuge for 30 seconds.
  4. The sample is now ready for testing.
   
• 操作流程
  1. Place the appropriate number of red sample dilution cups and clear sample cups into a sample cup rack. Label cups if necessary.
  2. Add 100 µL of sample extract to the red sample cup.
  3. Add 200 µL of sample diluent to the red dilution cup with the sample extract. Mix by pipetting up and down 5 times.
  4. Transfer 100 µL of diluted sample extract into a new clear sample cup.
  5. Place a new Reveal Q+ for Ochratoxin test strip with the sample end down into the sample cup and set timer for  9 minutes. Ensure the test strip comes into contact with liquid and begins to wick.
  6. Remove the strip from the sample cup after it has developed for 9 minutes and read immediately (within 30 seconds).
   
• 稀釋步驟(樣品超過20ppb需重新稀釋及測量)
  1. Add 100 µL sample filtrate to a sample collection tube.
  2. Add 200 µL 70% methanol solution to the sample collection tube. Mix well.
  3. Place the appropriate number of red sample dilution cups and clear sample cups into a sample cup rack. Label cups if necessary.
  4. Add 100 µL of diluted sample extract (from step 2) to the red sample cup.
  5. Add 200 µL of sample diluent to the red dilution cup with the sample extract. Mix by pipetting up and down 5 times.
  6. Transfer 100 µL of diluted sample extract into a new clear sample cup.
  7. Place a new Reveal Q+ for Ochratoxin test strip with the sample end down into the sample cup and set timer for  9 minutes. Ensure the test strip comes into contact with liquid and begins to wick.
  8. Remove the strip from the sample cup after it has developed for 9 minutes and read immediately (within 30 seconds).

• 產品說明書：連結
• 操作手冊：連結
• 物質安全資料表(Safety Data Sheet; SDS)：中文連結、英文連結

參考規範：食品中污染物質及毒素衛生標準

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