AttoPhos® AP Fluorescent Substrate System, a highly sensitive fluorescent alkaline phosphatase (AP) substrate maintains a low fluorescence signal until enzymatically acted upon, yielding detection of AP to as little as 0.1 attomole. The result is minimal signal fluorescence from interfering biological molecules.
The substrate has linear kinetics over five orders of magnitude of AP concentration. Excitation is at 435nm, emission at 555nm and large Stokes' shift (≈120nm).