A coated-tube radioimmunoassay for beta-thromboglobulin.

A solid phase radioimmunoassay for beta-thromboglobulin is presented which has the advantage of easy technical performance. The antibody was absorbed onto polystyrene tubes and the separation of free and bound radiolabelled tracer was performed by simply sucking the tubes empty after incubation. The assay is precise and accurate but not particularly rapid, since an overnight incubation is needed. Maximum assay sensitivity was found to be 5.6 ng/ml beta-thromboglobulin for plasma samples. Preliminary studies showed that the sensitivity can be increased by the use of a more dilute antiserum. The plasma concentration of beta-thromboglobulin in 37 normal subjects was 17 +/- 4 ng/ml. The analytical performance of the assay corresponds to a commercial liquid-phase kit used for reference.