Not every Kinase will work in an in vitro assay and a peptide that is phosphorylated by a kinase in vitro does not necessarily reflect that kinase's physiological target. However, kinase kits provide efficient way to monitor the activity of a kinase and screen compounds that will affect this function.

I know about a platform offered by Invitrogen called Z-LYTE kinase assay. the detection method relies on the proximity of two fluorescent dyes. Does anyone know about this kit and others available in the market?