Alternatives to radioimmunoassay: labels and methods.

We review the following labels used as substitutes for radioisotopes in immunoassay systems: bacteriophages, chemiluminescence precursors, fluorochromes, fluorogens, fluorescence quenchers, enzymes, coenzymes, inhibitors, substrates, various particulates, metal atoms, and stable free radicals. New methods for performing immunoassays with these labels are described where appropriate. Methods that require no separation steps and offer special promise for easy automation are noted.

A sensitive manual enzyme immunoassay for thyroxine.

We describe an immunoassay for thyroxine in serum. In the assay specific antibody covalently bonded to latex particles is used, along with horseradish peroxidase as the label, and o-phenylenediamine as the chromogen. The flexible protocol is designed for manual execution.

Solid-phase enzyme immunoassay for herpes simplex virus.

An enzyme immunoassay was used for the rapid detection of herpes simplex virus type 1 (HSV-1). The test utilized specific antibodies to HSV-1 attached to a solid phase. A laboratory preparation of HSV-1 was detectable in amounts of greater than or equal to 50 50% tissue culture-infective doses by this method.