US 6,618,934 B1 · Method of manufacturing small volume in vitro analyte sensor

Abstract

A sensor utilizing a non-leachable or diffusible redox mediator is described. The sensor includes a sample chamber to hold a sample in electrolytic contact with a working electrode, and in at least some instances, the sensor also contains a non-leachable or a diffusible second electron transfer agent. The sensor and/or the methods used produce a sensor signal in response to the analyte that can be distinguished from a background signal caused by the mediator. The invention can be used to determine the concentration of a biomolecule, such as glucose or lactate, in a biological fluid, such as blood or serum, using techniques such as coulometry, amperometry, and potentiometry. An enzyme capable of catalyzing the electrooxidation or electroreduction of the biomolecule is typically provided as a second electron transfer agent.

Claims31

Dependent claims

A method of manufacturing a plurality of electrochemical sensors, the method comprising the steps of:

(a) forming a plurality of working electrodes on a first electrode region of a substrate;
(b) forming a plurality of counter electrodes on a second electrode region of the substrate;
(c) disposing a spacer layer on one of the first and the second electrode regions;
(d) removing a portion of the spacer layer to define sample chamber regions;
(e) folding the substrate with the spacer layer between the first electrode region and the second electrode region to form a layered structure;
and
(f) separating the layered structure into a plurality of electrochemical sensors, each electrochemical sensor comprising at least one working electrode, at least one counter electrode, and at least one sample chamber region.

4 more elements

A method of manufacturing electrochemical sensors, the method comprising the steps of:

(a) forming a plurality of working electrodes on a first region of a first substrate, the working electrodes comprising a material selected from the group consisting of gold, carbon, platinum, ruthenium dioxide, and palladium;
(b) forming a plurality of counter electrodes on a second region of the first substrate, the counter electrodes comprising a material selected from the group consisting of gold, carbon, platinum, ruthenium dioxide, and palladium;
(c) disposing a spacer layer overlaying the working and counter electrodes, the spacer layer having a thickness of no more than 0.2 mm;
(d) removing a portion of the spacer layer to define a portion of a boundary for a sample chamber;
(e) overlaying the first substrate and the spacer layer with a second substrate to form a layered structure;
and
(f) separating the layered structure into a plurality of electrochemical sensors, each electrochemical sensor comprising:
(i) at least one working electrode having a working area of no more than about 0.01 cm2,
(ii) at least one counter electrode, wherein each at least one working electrode is spaced from each at least one counter electrode by 25-1000 micrometers, and
(iii) at least one sample chamber having a volume less than 1 microliter and including a circular recess having al least a portion of the working electrode and a diffusible redox mediator situated in the recess.

7 more elements

Dependencies are inferred from the claim text.

Method of manufacturing small volume in vitro analyte sensor

Life of this patent

Method of manufacturing small volume in vitro analyte sensor

Life of this patent

Abstract

Claims31