Butyrylcholinesterase (BChE) Fluorescent Activity kit is a simple, sensitive and stable kit that measures BChE activity in a wide variety of samples. The kit contains everything needed to measure activity, including the microtiter plate. Diluted samples are added to the wells. The reaction is initiated by addition of a reaction mix containing the butyrylthiocholine substrate.. After a 20 minute incubation, the signal is read at 510nm with excitation at 390nm. The activity can also be read kinetically. A stable human BChE standard solution is provided to generate a standard curve for the assay. The assay shows almost zero reactivity with AChE.