Patent ID: 7041209

Claim:
An amperometric biosensor system for the detection of analytes comprising: a) at least one biocatalyst producing a pH change by its interaction with the analyte; the biocatalyst not belonging to a group of oxidoreductase enzymes; b) at least one pH-sensitive redox compound, in the form of a monomer, exhibiting different redox properties in its protonated and non-protonated forms selected from the group consisting of cyclic hydrocarbons, containing from 4 to 30 carbon atoms and substituted with at least one group selected from —OH, —SH, —NH 2 , ═O, ═S, ═NH, —OR 1 , —SR 1 , —NHR 1 , —NR 1 R 2 , and ═NR 1 , wherein R 1 and R 2 are hydrocarbon chains optionally further substituted, or selected from the group consisting of heterocyclic compounds containing from 3 to 30 carbon atoms and one or more heteratoms selected from the group consisting of N, S, O, Se, Te, B, P, As, Sb, and Si, optionally substituted with a group selected for —OH, —SH, —NH 2 , ═O, ═S, —NH, —OR, —SR 1 , —NHR 1 , —NR 1 R 2 , and ═NR 1 , wherein R 1 and R 2 are independent hydrocarbon chains; c) a working electrode; and d) a reference electrode; e) the electrodes being connected through an ammeter.