Quick Review Cards for Medical Laboratory Science

Enzyme Immunoassays (EIA)

Formats continued

Immunology Review 393

METHOD

Rapid ELISA

Enzyme-multiplied
immunoassay
technique (EMIT)

OTHER

May have built in control. Usually

qualitative.

Used for determination of low mo-

lecular weight analytes not readily

measured by other methods, e.g.,

hormones, therapeutic drugs, drugs

of abuse. Automated.

DESCRIPTION

Membrane based

Homogeneous

PRINCIPLE

Reagent ag or ab bound to membrane in sin-

gle use cassette. Sample added. Presence of

ag-ab complex indicated by colored rxn.

Ag in specimen & enzyme-labeled ag com-

pete for binding sites on reagent ab. When

enzyme-labeled ag binds, enzyme activity

inhibited. Enzyme activity is directly propor-

tional to concentration of ag in specimen.