Test Principle ImmunoCAP Specific IgE

The technology is based on an extremely high total binding capacity, achieved through a high binding capacity per mg cellulose in combination with an optimal amount of cellulose in each solid phase. This ensures binding of all relevant antibodies, regardless of antibody affinity, still giving low non-specific binding.

The ImmunoCAP solid phase consists of a cellulose derivative enclosed in a capsule. The hydrophilic, highly branched polymer provides an ideal microenvironment for allergens, binding them irreversibly while maintaining their native structure.

The test is designed as a sandwich immunoassay.

 
The allergen of interest, covalently coupled to the solid phase, reacts with the specific IgE in the patient sample. 
After washing away non-specific IgE, enzyme-labelled antibodies against IgE are added to form a complex.
After incubation, unbound enzyme-labelled anti-IgE is washed away and the bound complex is then incubated with a developing agent.
After stopping the reaction, the fluorescence of the eluate is measured. The higher the fluorescence, the more specific IgE is present in the sample.