A simple, rapid, efficient method for the preparation of gamma 32P-labeled guanosine triphosphate (GTP) and adenosine triphosphate (ATP).

A simplified new method for synthesis fo gamma 32P GTP and gamma 32P ATP is described. Radiophosphorus is incorporated into GDP and ADP to form GTP and ATP, respectively, in the phosphoglycerate kinase reaction. The product is separated by ion exchange resin chromatography. The procedure is simple, gives a product a high purity, and the label is confined to the gamma position.