This method is based on the antigen-antibody reaction marked by superconducting dots, using the principle of fluorescence lateral immunochromatography. The aflatoxin B1 in the sample extract combines with the labeled antibody on the test card and emits fluorescence, and the fluorescence intensity is related to the content of aflatoxin B1 in the sample. After the chromatography, the fluorescence intensity of the detection line and the control line on the test card is measured with an immunofluorescence analyzer, and the instrument automatically calculates the content of aflatoxin B1 in the sample according to the built-in standard curve.
Reagents and materials
Unless otherwise specified, all reagents used are of analytical grade, and laboratory water should meet the requirements of Grade 3 water in GB/T 6682.
Dilution buffer: provided by the superconducting quantitative point immunofluorescence quantitative detection card, or prepared according to the product instructions.
4 Extraction solution: Measure 550mL methanol into 450mL water, and mix well.
Instruments and equipment
Balance: the division value is 0.01g.
Crusher: After crushing, all samples can pass through a 20-mesh sieve.
Centrifuge: the speed is not less than 4000 r/min.
Immunofluorescence analyzer: It can measure and display the measurement results of superconducting quantitative point immunofluorescence quantitative detection card.
Aflatoxin B1 Superconducting Quantitative Point Immunofluorescence Quantitative Detection Card: Store at room temperature and avoid light. For specific storage conditions, refer to the instructions for use; see Appendix A for technical requirements.
Filter paper: use medium-speed quantitative filter paper.
Turn on the immunofluorescence analyzer (5.5).
Take out the superconducting quantitative spot immunofluorescence quantitative detection card (5.6), and lay it flat with the sample hole facing up.
Accurately pipette 75μL of the test solution (6.2.2) and add it to the sample hole of the test card.
After loading the test card, let it stand horizontally for 15 minutes to react, and then insert the test card into the immunofluorescence analyzer (5.5) within 3 minutes, and the instrument will automatically perform the test.
The immunofluorescence analyzer (5.5) will complete data reading and analysis within 13 seconds. The immunofluorescence analyzer will automatically display the content of aflatoxin B1 in the sample and save the test results.
If the displayed value of the immunofluorescence analyzer is >50 μg/kg, pipette 100 μL of the filtrate or supernatant in 6.2.2, add 300 μL of the sample extract (4.2), mix well and take 100 μL to a clean Add 400 μL of dilution buffer (4.1) to the centrifuge tube, mix well, and perform the determination according to 7.2 to 7.5.