Patent ID: 8012341

Claim:
A single use disposable electrode strip for attachment to the signal readout circuitry of a sensor system which measures ketone(s) in an aqueous sample, the strip comprising: a) an elongated support having a substantially flat, planar surface, adapted for releasable attachment to the readout circuitry; b) at least two conductors extending along the surface and comprising a first conductive element and a second conductive element for connection to the readout circuitry; c) a plurality of electrodes, at least one active electrode on the surface in contact with the first conductive element and a counter/reference electrode in contact with the second conductive element, wherein the active electrode comprises a conductive ink, the conductive ink comprising a conductive compound, ketone specific enzymes and a mediator compound, wherein the mediator compound consists of one of the two following formulae: where X and Y can independently be oxygen, sulphur, CR 3 R 4 , NR 3 , or NR 3 R 4+ or the functional group CZ 1 Z 2 , where Z 1 and Z 2 are electron withdrawing groups; R 1 and R 2 can independently be a substituted or unsubstituted aromatic or heteroaromatic group; and R 3 and R 4 can independently be a hydrogen atom, a hydroxyl group or a substituted or unsubstituted alkyl, aryl, heteroaryl, amino, alkoxyl, or aryloxyl group ; and d) said active electrode and the reference/counter electrode being configured so that a small drop of the aqueous sample provides an electrical conduction path between the electrodes.