Patent ID: 8802390

Claim:
A method for detecting for the presence of a protease in a test sample, said method comprising: (a) adding a test sample to a solid support comprising an electrode comprising: (i) a self-assembled monolayer (SAM); (ii) a covalently attached electroactive active moiety (EAM) comprising a transition metal complex with an E 0 , wherein said EAM comprises a ferrocene; and (iii) a plurality of proteins attached to said electrode, wherein said proteins are arranged so that the EAM is at least partially shielded by the proteins from exposure to a solution and comprise a cleavage site of said protease, wherein the cleavage site is near the height of said EAM; (b) cleaving a plurality of said proteins with said protease, if said protease is present, such that when the proteins are cleaved at the cleavage site, the EAM is exposed to the solution; and (c) determining the presence of said protease by measuring a change of said E 0 .