For laboratory use only. S-2302 is a chromogenic substrate for plasma kallikrein. The substrate has been used for the determination of Prekallikrein, Kallikrein inhibitors, FXII, Kallikrein-like activity in plasma, Prekallikrein activator in albumin and immunoglobulin preparations. Each vial contains chromogenic substrate S-2302 25 mg and mannitol 60 mg as a bulking agent.