A Simple and Sensitive Radioimmunoassay for Adenosine

Abstract We developed a simple and sensitive radioimmunoassay (RIA) for adenosine. The RIA is based on the double antibody method with adenosine 2′,3′-0-disuccinyl-3-[125 I]-iodotyrosine methylester (diSc-adenosine-[125 I]-TME) as a tracer. Anti-adenosine antiserum for the RIA was raised in rabbits immunized with diSc-adenosine conjugated to human serum albumin (diSc-adenosine-HSA). All samples and standards were succinylated prior to assay. The present immunoassay allows detection of 6.25–400 pmol/ml of adenosine in sample. Values obtained by the RIA and by a HPLC analysis showed a high correlation with correlation coefficient of 0.997. In order to determine adenosine in plasmas, blood cells must be separated in the presence of 6 mM EDTA, 0.006% dipyridamole (Dip) and 23 μM 2′-deoxycoformycin (dCF) at 2°C. Adenosine in plasma could be accurately determined by the proposed method even