Practices and pitfalls in immunologic methodology.

RIA is used in thousands of laboratories around the world to measure multiple classes of substances of biologic interest, both peptidal and non-peptidal in nature. It is now evident that if there is a need to measure an organic substance of biologic interest and there is no simple method to do so, some imaginative investigator will develop the appropriate RIA procedure. Although new assays are continuously being described and their usefulness documented, these reports generally do not describe how or whether the assay has been optimized for the particular antiserum. Some of the practices and problems described in this report should serve as a guide in optimizing RIA procedures.