Slide immunoenzymatic assay for human IgE (SIA-IgE).

A rapid and inexpensive method is described for determination of human serum IgE using 5-microliter samples. The slide immunoenzymatic assay for IgE (SIA-IgE) is carried out on a glass slide in which up to 24 samples can be tested including controls and standards; up to four of these slides can be read automatically in conventional vertical beam readers. Flat circles on the slide are covered with a layer of biotinylated antibody specific for human IgE (trapping antibody). Five microliters of serum sample is dropped to cover each circle, and the slide is incubated. The circles are washed with water, dried, incubated under 10 microliters of enzyme-labeled antibody to human IgE, then washed again, and covered with 10 microliters of enzyme substrate. The intensity of color generated is measured at the proper wavelength. The method is simple, accurate and non-radioactive and can be completed within 2 h.