There are latex agglutination test and blood inhibition test, radioimmunoassay (RIA), enzyme-linked immunosorbent assay (ELISA), monoclonal antibody colloidal gold test, and this experiment is derived from the Mudanjiang Medical College undergraduate 5-year clinical laboratory guide.
Operation method
Detection of human chorionic gonadotropin by latex coagulation inhibition test
Principle
Experimental principle: HCG as an antigen injected into the rabbit, so that it produces the corresponding antibody, (anti-HCG antibody) when this antibody and the antigen HCG will meet the immune response, but this reaction can not be seen by the naked eye using chemical methods to cross-linking of HCG in polystyrene latex particles to make the HCG latex antigen, when the combination of this antigen and HCG antibody can be seen in the latex particles of the agglutination. The test is performed by mixing the urine specimen with the antiserum. If there is a large amount of HCG-binding antibody in the urine and HCG latex is added, no visible agglutination (inhibition of the reaction that should be agglutinated) will occur, which is considered to be a positive pregnancy test. If the HCG content in the urine is very low, not enough to interact with the antibody serum, and agglutination can still occur when HCG latex is added, resulting in granular, small precipitates, then the pregnancy test is negative. Move Laboratory reagents and equipment: Caveat Room temperature during the experiment, such as below 20 ℃ reaction slow, should be appropriate to extend the reaction time of the two segments of the test in urine, antiserum, latex antigen added in the order can not be reversed, and the droplet size should be consistent, each test should be done to know the positive and negative control. For more product details, please visit Aladdin Scientific website.
1, pregnancy diagnostic latex antigen is uniform turbid, shake well before use.
2, pregnancy diagnosis antiserum.
3, the reaction plate system back painted with black paint, red paint on the front divided into a number of 2.5cm × 2.5cm square glass plate, can also be replaced by ordinary slides, the above reagents and equipment can be purchased by the biological supply unit, the use of the instructions should be followed, the reagents should be stored in the refrigerator at 2-8 ℃ (not frozen) before the test is taken out so that the temperature rises to room temperature and then applied.
Collection of experimental specimens:
①, the container must be clean, the specimen should be sent for examination.
②, such as turbid urine, should be filtered and then used.
③, specimen dilution is easy to produce false negatives, it should be used early in the morning for the first urine specimen is good.
④, severe proteinuria (more than 2 +), hematuria and bacterial contamination of the specimen are not suitable for this test.
Experimental method: add one drop of urine to the reaction plate, add one drop of anti-HCG serum, shake and mix for 30 seconds. Then leave it for 2-3min, then add one drop of latex antigen solution, continue to shake the slide slowly for 2-3min, and observe the result with naked eyes in a better light.
Judge the results of the experiment:
l, such as the appearance of uniform milky opaque turbidity, indicating that the collection did not occur, that is, a positive reaction for pregnancy diagnostic test. Reported as a positive LAI test.
2、If there are particles of small lumps of agglutination, and the liquid is uniformly turbid, disappear and show transparency, that is, a negative pregnancy test. Reported as negative LAI test.
3、If there is a uniform and consistent bleached milk agglutination, it is a non-specific reaction. The specimen should be centrifuged to precipitate the supernatant retest to identify the cause.