NEW COLORIMETRIC METHOD FOR AUTOMATIC DETERMINATION OF ADENOSINE AT MICROMOLAR LEVEL

A new and fully automated colorimetric method for the determination of adenosine at the micromolar level is described: chlorinated adenosine accelerated the bleaching of alkali green by hypochlorite solution, and the resultant change in optical density at 625 mμ was observed using a Technicon AutoAnalyzer. The use of an enzyme was not required. Adenosine samples were determined by the new technique and also by the classic spectrophotometric method: similar results were obtained by both procedures (correlation coefficient = 0.98, P < 0.0001, but the former was about 8 times as sensitive and it was easier to use. The new technique has excellent reproducibility and is apparently very specific for adenosine; AMP, cyclic AMP, ADP, and ATP have similar but lower activity, GMP has much lower activity, and adenine, UMP, CMP, and IMP have no appreciable activity at all. The method can be used for continuous measurement of the rate of uptake, production, or degradation of adenosine or adenosine phosphates in biological material, even in vivo. © 1969.