ADA Activity Assay, inosine formed from the breakdown of adenosine is detected via a multi-step reaction, resulting in the formation of an intermediate that reacts with the ADA Probe to generate a fluorescent product. The kit measures total Activity of Adenosine Deaminase with limit of quantification of 10 μU recombinant Adenosine Deaminase. The range of the assay is from 10-100 μU.