Table of Contents
What is agglutination inhibition test?
Gravindex is an agglutination inhibition test performed on a urine sample to detect pregnancy. It is based on double antigen antibody reaction. The test detects the prevention of agglutination of HCG-coated latex particles by HCG present in the urine of pregnant women.
Are pregnancy tests agglutination?
Direct Pregnancy Latex Test The presence of HCG in a urine specimen results in the formation of an agglutination matrix which is visually differentiated from the non-agglutinating negative control. The direct pregnancy latex test is calibrated to detect HCG levels at or greater than 200mIU/ml.
What do monoclonal antibodies on pregnancy test kits bind with?
Pregnancy test kits use monoclonal antibodies . These have been designed to bind with a hormone called HCG which is found only in the urine of pregnant women. Monoclonal antibodies are attached to the end of a pregnancy test stick onto which a woman urinates.
What is antibody agglutination?
Agglutination is the process that occurs if an antigen is mixed with its corresponding antibody called isoagglutinin. This term is commonly used in blood grouping. This occurs in biology in two main examples: The clumping of cells such as bacteria or red blood cells in the presence of an antibody or complement.
What is agglutination inhibition reaction?
Definitions and classification of agglutination reactions Agglutination inhibition or hemagglutination inhibition refers to the inhibition of these reactions by soluble antigen which reacts with the combining sites of the antibodies and thereby prevents their binding to and agglutination of the particles.
What are monoclonal antibodies GCSE?
Monoclonal antibodies are identical copies of one type of antibody. Antibodies are proteins produced by a type of white blood called lymphocytes . Pathogens have proteins on their surface called antigens .
What are monoclonal antibodies used for GCSE?
Research scientists use monoclonal antibodies to locate or identify specific molecules in a cell or a tissue. Scientists will produce monoclonal antibodies which are linked to a specific molecule or fluorescent dye. For example, green fluorescent protein.
Which antibodies can agglutinate?
Antibodies vary in their ability to cause agglutination, as IgM antibodies agglutinate RBCs carrying target antigens quite efficiently, while IgG antibodies typically bind to incompatible RBCs but do not directly agglutinate them.
What two cell types react during an agglutination reaction?
When antibodies are mixed with their corresponding antigens on the surface of large, easily sedimented particles such as animal cells, erythrocytes, or bacteria, the antibodies cross-link the particles, forming visible clumps. This reaction is termed agglutination.
What agglutinate means?
1 : to unite or combine into a group or mass. 2 : to form words by agglutination. agglutinate.
How do you test for agglutination in hCG?
Examine for agglutination macroscopically. Compare the results with positive and negative controls. Agglutination show a positive reaction. If the test is positive, the amount of HCG will be equal to 0.3 IU/ml or above while in case of a negative reaction (no agglutination) less Than 0.3 IU/ml.
Can urine from a pregnant woman inhibit agglutination of latex particles?
The addition of urine from a pregnant woman, which contained HCG, inhibited agglutination of the latex particles when the anti-HCG antibody was added; thus the absence of agglutination indicated pregnancy.
What is an example of agglutination inhibition?
A modification of the agglutination reaction, called agglutination inhibition, provides a highly sensitive assay for small quantities of an antigen. For example, one of the early types of home pregnancy test kits included latex particles coated with human chorionic gonadotropin (HCG) and antibody to HCG (Figure 6-8).
How do home pregnancy test kits work?
The original home pregnancy test kit employed hapten inhibition to determine the presence or absence of human chorionic gonadotropin (HCG). The original test kits used the presence or absence of visible clumping to determine whether HCG was present.