Aflatoxin M1 (AFM1) ELISA kit instruction manual

This kit is for research use only.
1 Purpose of use:
This kit is used to detect the content of aflatoxin M1 (AFM1) in feed and grain.
2 Experimental principle The kit uses a direct competitive ELISA method, coated with aflatoxin conjugated antigen in a microplate, added aflatoxin M1 (AFM1) standard or sample, free aflatoxin M1 (AFM1) Aflatoxin pre-coated with microwell strips
M1 conjugated antigens compete with each other for anti-aflatoxin M1 (AFM1) abzyme labeling, developed with TMB substrate, the color changes from blue to yellow after addition of stop solution, and detection is carried out with a microplate reader at a wavelength of 450 nm. The absorbance value is inversely proportional to the content of aflatoxin M1 (AFM1) in the sample, and the content of aflatoxin M1 (AFM1) in the sample is calculated by the standard curve.
3 Kit composition
3.1 Pre-coated AFM1 detachable enzyme-labeled plate conjugated with antigen: 1 piece (12 wells × 8 strips).
3.2 AFM1 standard product: 6 bottles (1ml / bottle), the contents are: 0 ng / ml, 0.1 ng / ml, 0.3 ng / ml, 0.9 ng / ml, 2.7
ng / ml, 8.1 ng / ml.
3.3 Anti-AFM1 antibody conjugate: 1 bottle (6ml).
3.4 Color developing solution A: 1 bottle (6ml).
3.5 Color developing solution B: 1 bottle (6ml).
3.6 Stop solution: 1 bottle (6ml), 2M sulfuric acid.
3.7 Sample diluent: 1 bottle (10 ×, 6ml), used for sample dilution.
3.8 Concentrated washing solution: 1 bottle (20 ×, 20ml) for washing plates.
3.9 A manual.
4 Materials needed but not provided
4.1 Equipment
4.1.1 Wavelength 450nm microplate reader.
4.1.2 Crusher.
4.1.3 Measuring cylinder.
4.1.4 Oscillator.
4.1.5 Funnel.
4.1.6 Whatman No 1 or equivalent filter paper.
4.1.7 Micro pipette.
4.2 Reagent
4.2.1 Deionized water or distilled water.
4.2.2 Methanol.
5 Storage
5.1 The kit is stored at 2 ~ 8 ℃, do not freeze
5.2 Unused microplates should be sealed and dried
6 Notes
6.1 Please read the instructions carefully before using the kit.
6.2 Do not use expired kits.
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6.3 Before using the kit, return the reagent to room temperature (25 ± 2 ℃). It is recommended to return to temperature for at least 2 hours.
6.4 The standard product contains aflatoxin. Special care should be taken when using it. Gloves should be worn during operation.
6.5 The stop solution contains sulfuric acid, which prevents burns to the skin and corrosion of clothing when used.
6.6 The tips used for different standards and samples can not be mixed, otherwise it will affect the test results.
6.7 The reagents in different batch kits should not be mixed; the tips used for different standards and samples should not be mixed, otherwise it will affect the experimental results.
6.8 When diluting the sample, the sample diluent in this kit must be used, otherwise it will affect the experimental results
6.9 Avoid foaming when mixing reagents.
7 Working fluid preparation
7.1 AFM1 standard solution: 0ng / ml, 0.1ng / ml, 0.3 ng / ml, 0.9 ng / ml, 2.7 ng / ml, 8.1ng / ml
7.2 Concentrated washing solution: dilute with distilled water at 1:20 (1 + 19) for later use
7.3 Sample diluent: 1:10 (1 + 9) diluted with distilled water for use
7.3 Developer: reserved, avoid direct light
7.4 Reaction stop solution: reserved
8 Sample processing procedures (samples should be strictly operated in accordance with the instructions during the extraction process, and they should be accurately diluted during the extraction process, otherwise the results will be inaccurate, and the samples should be stored in a cool and dark place and stored in refrigerator)
8.1 Take 10g crushed sample and add 20ml 70% methanol solution
8.2 Vibrate vigorously for 3 minutes
8.3 Filter with Whatman No 1 filter paper
8.4 Take 100μl of processed sample and add 400μl of sample diluent
8.5 Take 50μl of diluent for analysis (dilution factor 10)
9 Enzyme-free analysis steps
9.1 Experimental notes
9.1.1 Before starting the experiment, please restore all reagents to room temperature (25 ± 2 ℃) outside the box for about 2 hours. After warming to room temperature (25 ± 2 ℃), take out the microporous strips again. Re-seal the microporous strips and dry immediately at 2 ~ 8 ℃. Note: Make sure that the temperature is sufficient, otherwise the accuracy and accuracy of the test will be affected.
9.1.2 Please put the reagent back to 2 ~ 8 ℃ immediately after use
9.1.3 Please do not change the analysis program
9.1.4 Please use an accurate micropipette
9.1.5 Once the operation starts, please do not interrupt any program
9.1.6 The reproducibility of ELISA results greatly depends on the operating procedures, please strictly follow the requirements
9.1.7 To avoid cross-contamination, each standard and sample should be loaded with different tips
9.1.8 Do not let the tip touch the solution or inner surface of the microwell when loading
9.2 Analysis steps
9.2.1 Number in advance, mark the position of B0, standard and sample, double hole detection is recommended
9.2.2 Take the required number of micropores (micropore strips are removable), reseal the excess strips and immediately put them back at 2 ~ 8 ℃ to store
9.2.3 The sample diluent (10 ×) and concentrated washing solution (10 ×) are diluted into working solution (diluted with distilled or deionized water)
9.2.4 Add 50 μl of 0.0 ng / ml standard solution to well B0
9.2.5 Add 50 μl of standard solution to each standard well
9.2.6 Add 50 μl of sample solution to each sample well
9.2.7 Add 50 μl of anti-aflatoxin M1 abzyme conjugate to all wells
9.2.8 Gently shake the reaction plate for a few seconds.
9.3 Warm bath at 37 ° C for 30min (Tap the reaction plate from time to time during the warm bath to reduce double-hole errors)
9.3.1 Shake off the liquid in the well and wash the microplate 5 times with washing liquid
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body.
9.4 Response
9.4.1 After the washing procedure is completed, immediately add 50 μl of chromogenic solution A and 50 μl of chromogenic solution B to each microwell with a micropipette; shake the reaction plate slightly to mix thoroughly
9.4.2 37 ℃ warm bath for 10min
9.4.3 Add 50μl of stop solution to each well and mix well
9.4.4 Detect the absorbance at 450nm and read the result within 5min.
10 Result calculation
10.1 Quantitative analysis
10.1.1 The average value of the absorbance value of each concentration standard solution and sample obtained (B) divided by the first standard (0 standard)
The absorbance value (B0) is multiplied by 100%, which is the percent absorbance value.
B—Average absorbance value of standard solution or sample solution
B0—The average absorbance value of 0μg / L standard solution
10.1.2 Use the logarithmic value of the concentration of aflatoxin M1 as the X axis and the percent absorbance value as the Y axis to draw a standard curve. According to the percent absorbance value of the sample, the abscissa of the corresponding point can be obtained from the curve, which is the logarithmic value of the AFM1 concentration, and the antilogarithm is the AFM1 concentration C (ng / ml) in the measurement solution.
10.1.3 Because the sample has been pre-diluted, the sample concentration obtained from the standard curve must be multiplied by its dilution factor.
10.2 Semi-quantitative determination
10.1.1 Visual semi-quantitative determination: first select an appropriate standard solution to run with the sample, and judge whether the concentration value of the sample is less than or greater than the standard value based on the comparison of the absorbance value of the sample and the standard.
10.1.2 Instrument semi-quantitative determination: first select an appropriate standard solution to run with the sample, and determine whether the concentration value of the sample is less than or greater than the standard value according to the color depth comparison of the sample and the standard product.
11 Cross-reaction of specific substances Aflatoxin B1 100%
Aflatoxin B2 80%
Aflatoxin G1 75%
Aflatoxin G2 30%
12 Kit parameters The lower detection limit of this kit is 0.1ppb
The best value of B0 absorbance should be greater than 1.0
The error in the absorbance plate of the kit is less than 8%, and the error between the plates is less than 15%.
The recovery rate of the tissue sample extraction method provided in this specification is greater than 80%.
13 Standard curve mode (for reference only)
The standard curve range provided by the kit is 0.1ng / ml ~ 8.1ng / ml.
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14 Limitations of analysis The samples tested positive by this kit should be confirmed by another method such as HPLC or GC / MS.