Patent ID: 8092784

Claim:
A fluorogenic enzyme substrate of formula: DYE-(B) m wherein: DYE comprises a fluorogenic dye which is an asymmetric cyanine dye of formula: wherein: X comprises O or S; n is selected from 0, 1, 2 and 3; ψ comprises a biologically compatible counter ion; d is a number of ψ sufficient to render overall charge of the substrate neutral; the dotted line represents atoms of at least one fused aromatic ring, optionally comprising at least one quaternized or unquaternized nitrogen; at least one ligand, but no more than two ligands, of ligands R 4 , R 5 , R 6 and R 7 comprises at least one B which is an enzyme substrate moiety capable of reacting with said enzyme, such that said reacting results in an increase in the fluorescence of said fluorogenic dye; when ligand R 4 does not comprise B, ligand R 4 comprises H; a C1 to about C6 alkyl; a C1 to about C6 alkoxy; a halogen; or an aryl meta to X, wherein the aryl optionally comprises at least one hetero atom of hetero atoms N, O and S; when ligand R 5 does not comprise B, ligand R 5 comprises a C1 to about C6 alkyl; when ligand R 6 does not comprise B, ligand R 6 comprises H; a C1 to about C10 alkyl, wherein the alkyl optionally comprises at least one hetero atom of hetero atoms N, O and S; a halogen; a C1 to C10 alkoxy, wherein the alkoxy optionally comprises at least one hetero atom of hetero atoms N, O, and S; a C1 to C10 alkylmercapto, wherein the alkylmercapto comprises at least one hetero atom of hetero atoms N, O, and S; a C2 to about C12 dialkylamino, wherein the dalkylamino optionally comprises at least one hetero atom of hetero atoms N, O, and S; a substituted or an unsubstituted aryl, wherein the aryl optionally comprises 1 to 3 hetero atom(s) of hetero atoms N, O, S and a halogen; when ligand R 7 does not comprise B, ligand R 7 comprises H; a C1 to about C10 alkyl, optionally comprising an aryl, and optionally comprising at least one hetero atom of hetero atoms N, O, and S; a substituted or an unsubstituted aryl, optionally containing 1 to 3 hetero atom(s) of hetero atoms N, O, S and a halogen; and independently, each ligand of ligands R 8 and R 9 comprises H; a C1 to about C10 alkyl, optionally comprising at least one hetero atom of hetero atoms N, O, and S; a halogen; a C1 to C10 alkoxy, wherein the alkoxy optionally comprises at least one hetero atom of hetero atoms N, O, and S; a C1 to C10 alkylmercapto, wherein the alkylmercapto optionally comprises at least one hetero atom of hetero atoms N, O, and S; a C2 to about C12 dialkylamino, optionally comprising at least one hetero atom of hetero atoms N, O, and S; or a substituted or an unsubstituted aryl, optionally comprising 1 to 3 hetero atom(s) of hetero atoms halogen, N, O and S; or ligand R 8 and ligand R 9 in combination, form a fused aromatic ring, wherein the ring is optionally substituted by at least one substituent of a C1-C2 alkyl substituent, a C1-C2 alkoxy substituent, a C1-C2 alkyl-mercapto substituent, and a halogen substituent.