The kit is intended for detection of specific IgA antibodies in a sample by means of a sandwich type of the EIA method (i.e. a solid phase coated with specific antigen – antibody from the analysed sample – labelled antibody).
The labelled antibody (conjugate) is an animal immunoglobulin fraction to human IgA conjugated with horseradish peroxidase.
Peroxidase activity is determined in the test by a substrate containing TMB. Positivity is indicated when blue colour appears; after stopping solution has been added, blue changes to yellow. The yellow colour intensity is measured by a photometer at 450 nm, and it is proportional to the concentration of specific IgA antibodies in the sample.