NEW PERSPECTIVES IN RADIOIMMUNOASSAY

In addition to providing the basis of 'ultrasensitive' immunoassays, nonisotopic labels permit development of 'user friendly' methodologies, including simple devices designed for extralaboratory use and intended to provide yes/no answers to basic diagnostic questions, for example, the presence of an infectious disease, the commencement of pregnancy etc. Immunosensors are also intended to fulfil these objectives (albeit yielding quantitative information), but despite much research the prospect of adequately sensitive instruments of this type remains remote. Finally, nonisotopic labels enable the development of a new generation of miniaturized multianalyte assays permitting in principle the determination of entire analyte menus in small samples of body fluids. Such technologies will resemble those employed in compact disk recorders and other data-storage devices, differing only in that light emitted from discrete zones on a solid surface is fluorescent (or possibly chemiluminescent) rather than reflected, and yields chemical rather than physical information. The emergence of such technologies, will, inter alia, facilitate the screening of entire populations for infectious disease, endocrine dysfunctions, genetic abnormalities etc. using, for example, finger-tip blood samples, throat and endocervical swabs, and hopefully will contribute to the large-scale diagnosis and ultimate reduction of disease.