Human Endostatin ELISA Kit Instructions for Use

Human Endostatin ELISA Kit

  ( used in other biological fluids such as serum, plasma, cell culture supernatant, and saliva )

principle

This experiment used double antibody sandwich ABC-ELISA. The anti-human Endostatin monoclonal antibody was coated on the plate, the endostatin in the standard and the sample was combined with the monoclonal antibody, and biotinylated anti-human Endostatin was added to form an immune complex attached to the plate, horseradish peroxidase. The labeled Streptavidin is combined with biotin, and the substrate working solution is blue. Finally, the stop solution sulfuric acid is added, and the OD value is measured at 450 nm. The concentration of Endostatin is directly proportional to the OD value, and the concentration of Endostatin in the sample can be obtained by drawing a standard curve.

Kit composition ( 2-8 ° C preservation)

Prepare reagents and collect blood samples

1. Collect specimens: serum, plasma (EDTA), cell culture supernatant, tissue homogenate, saliva, etc., as soon as possible, store at 2-8 ° C for 48 hours; freeze for a longer time (-20 °C or -70 °C) Save to avoid repeated freezing and thawing. Pre-measure the normal specimen with a dilution of the specimen at least 1 : 50 (take 20ul, add 980ul of the diluted solution, diluted 50 times). Saliva can be detected directly without dilution.

2. Standard product preparation: Add 0.5ml distilled water before use and mix well to form a solution of 8000pg/ml. Set 8 tubes of standard tubes, and add 300 ul of standard dilution solution to each tube. Add 300 ul of the standard solution of 8000 pg/ml to the first tube, mix and aspirate 300 ul with the sampler, and transfer to the second tube. Repeat the dilution in this way, and remove 300 ul from the seventh tube and discard it. The eighth tube is a blank control.

3. The 10× specimen dilution was diluted 1:10 with distilled water (example: 1 ml concentrated dilution + 9 ml distilled water).

4. Washing solution: diluted 1:20 with distilled water (example: 1 ml concentrated washing solution added to 19 ml of distilled water)

Test procedure

1. Loading: Add 100 ul of standard or sample to be tested in each well. Mix the reaction plate thoroughly and let it stand at 37 °C for 120 minutes.

2. Wash the plate: Wash the plate thoroughly with washing solution 4-6 times, and dry it on the filter paper.

3. Add 100 ul of the first antibody working solution to each well. The reaction plate was thoroughly mixed and placed at 37 ° C for 60 minutes.

4. Wash the board: the same as before.

5. Add 100 ul of enzyme-labeled antibody working solution per well. The reaction plate was placed at 37 ° C for 30 minutes.

6. Wash the board: same as before.

7. Add 100 ul of substrate working solution per well, set 37 The reaction was carried out in the dark at °C for 15 minutes.

8. Add 100 ul of stop solution to each well and mix.

9. Measure the absorbance at 450 nm using a microplate reader within 30 minutes.

Result calculation and judgment

1. All OD values ​​should be subtracted from the blank value before calculation.

2. Take the standard products 4000, 2000, 1000, 500, 250, 125, 62.5, 0 pg/ml as the abscissa and OD as the ordinate. Draw on the coordinate paper and draw the standard curve.

3. Find the corresponding Endostatin content on the graph based on the OD value of the sample, and multiply by the dilution factor. .

Kit performance

1. Sensitivity: The minimum Endostatin assay concentration is less than 30 pg/ml.

2. Specificity: Recombinant or natural human Endostatin can be detected simultaneously. Does not cross-react with other human cytokines.

3. Repeatability: The coefficient of variation in both the plate and the plate is less than 10%.

Precautions

1. It is recommended to make double holes for the above standard holes and samples to be tested. The standard curve should be made at the same time for each measurement.

2. The washing process is critical. Insufficient washing will result in an accuracy error and an erroneous rise in the OD value.

3. After the slats are opened, the remaining slats should be sealed again to keep the slats dry .

4. This kit should be stored in a 4 ^o C refrigerator.

5. This kit is for scientific research only and cannot be used for clinical diagnosis!