Transcreener ADP² Kinase Assay Kits rely on direct detection of ADP using a proprietary antibody that binds with exquisite specificity and affinity to ADP, with negligible cross-reactivity to ATP. This exquisite selectivity allows direct detection of ADP in the presence of an excess of ATP, a requirement for kinase activity assays run under initial velocity conditions (e.g., ≤10% ATP consumption). The high affinity of the ADP antibody means that the assay has the sensitivity for robust detection of ADP down to 10 nM with Z’ values of 0.7 or greater, so you can use less of your precious enzyme.

Other ADP detection methods rely on complex assay schemes that use three or more enzymatic steps to convert ADP into a detectable signal. Each of the enzymes in the detection cascade is a potential target for the compounds being screened, which increases the risk of false positives or of missing a hit, and requires additional wells for counter-screening.