Giardia Iamblia Antigen ELISA Assay Kit

Additional Information

Assay Principle

This Eagle Biosciences  “sandwich” Fecal Giardia Iamblia Antigen ELISA is designed, developed and produced for the qualitative measurement of Giardia lamblia antigen in stool specimen. The assay utilizes the microplate-based enzyme immunoassay technique by coating highly purified antibody onto the wall of microtiter well.  Assay controls and fecal specimen are added to microtiter wells of microplate that was coated with a highly purified polyclonal anti-Giardia lamblia antibody on its wall. The Giardia lamblia antigen will be bound to the antibody coated plate after an incubation period. The unbound matrices are washed away and a HRP-conjugated monoclonal antibody which specifically recognizes the protein of Giardia lamblia is added for further immunoreactions.  After an incubation period, an immunocomplex of “Anti-Giardia Antibody – Giardia lamblia Antigen – HRP-conjugated Anti-Giardia Tracer Antibody” is formed if Giardia lamblia antigen is present in the test sample. The unbound tracer antibody and other protein or buffer matrix are removed in the subsequent washing step. HRP-conjugated tracer antibody bound to the well is then incubated with a substrate solution in a timed reaction and then measured in a spectrophotometric microplate reader. The enzymatic activity of the tracer antibody bound to giardia proteins captured on the wall of each microtiter well is directly proportional to the amount of Giardia lamblia antigen level in each test specimen

1. Place a sufficient number of anti-Giardia antibody-coated microwell strips in a frame to run giardia controls and unknown samples in duplicate.
2. Add 100 µL of controls and diluted patient stool samples into each designated microwell.
3. Cover the plate with a plate sealer and also with aluminum foil to avoid exposure to light.
4. Incubate plate at room temperature for 1 hour.
5. Prepare working anti-Giardia tracer antibody working solution by 1:21 fold dilution of the Anti-Giardia Tracer Antibody with the Tracer Antibody Diluent. For each strip, it is required to mix 1 mL of Tracer Antibody Diluent with 50 µL of Tracer Antibody in a clean test tube.
6. Remove the plate sealer. Decant the contents of each well. Wash each well 5 times by dispensing 350 µL to 400 µL of deionized or distilled water into each well and then completely aspirating the contents. Alternatively, an automated microplate washer can be used. (Note: The plate must not be washed with any ELISA wash buffer!)
7. Add 100 µL of above diluted tracer antibody working solution to each of the wells.
8. Cover the plate with one plate sealer and also with aluminum foil to avoid exposure to light.
9. Incubate plate at room temperature for 45 minutes.
10. Remove the plate sealer. Decant the contents of each well. Wash each well 5 times by dispensing 350 µL to 400 µL of deionized or distilled water into each well and then completely aspirating the contents. Alternatively, an automated microplate washer can be used. (Note: The plate must not be washed with any ELISA wash buffer!)
11. Add 100 µL of ELISA HRP Substrate into each of the wells.
12. Cover the plate with aluminum foil to avoid exposure to light.
13. Incubate plate at room temperature for 20 minutes.
14. Remove the aluminum foil.  Add 100 µL of ELISA Stop Solution into each of the wells. Mix gently.
15. Read the absorbance at 450 nm within 10 minutes in a microplate reader. As an alternative, one can interpret the test results visually by using the color code card included in the kit.