Sensor for in vitro determination of glucose
A process for the manufacture of small sensors with reproducible surfaces, including electrochemical sensors. One process includes forming channels in the surface of a substrate and disposing a conductive material in the channels to form an electrode. The conductive material can also be formed on the substrate by other impact and non-impact methods. In a preferred embodiment, the method includes cutting the substrate to form a sensor having a connector portion and a transcutaneous portion, the two portions having edges that define one continuous straight line.
1. A sensor for the in vitro determination of glucose level in a sample, the sensor comprising:
a substrate comprising a first recessed channel;
a first conductive material to provide an electrode disposed in the recessed channel on the substrate to substantially fill the channel such that the substrate and the conductive material form a substantially flat surface,
wherein a catalyst is mixed or dispersed in said first conductive material,
wherein the catalyst includes an enzyme, wherein the enzyme is mixed in a carbon ink to form a mixture,
wherein the sensor generates an electrical signal associated with a level of glucose in a volume sample of about 1 microliter or less.
2. The sensor of claim 1 , wherein the catalyst forms a conductive trace associated with a working electrode.
3. The sensor of claim 1 , wherein the substrate comprises a second recessed channel and a second conductive material is applied in the second recessed channel.
4. The sensor of claim 3 , wherein the first conductive material and the second conductive material are the same.
5. The sensor of claim 3 , wherein the first conductive material and the second conductive material are different.
6. The sensor of claim 1 , wherein the substrate includes an indentation.
7. The sensor of claim 1 , wherein a trace is associated with the electrode, the trace having a width of about 25 microns to 250 microns.
8. The sensor of claim 7 , wherein the trace has a width of about 75 microns or less.
9. The sensor of claim 8 , wherein the trace has a width of about 50 microns or less.
10. The sensor of claim 9 , wherein the trace has a width of about 25 microns or less.
11. The sensor of claim 1 , wherein the sensor is coupled to a skin piercer.
12. The sensor of claim 1 , comprising a tapered end.
13. The sensor of claim 1 , wherein the enzyme is glucose oxidase.
14. The sensor of claim 1 , wherein the enzyme is glucose dehydrogenase.
15. The sensor of claim 1 , wherein the enzyme is pyrroloquinoline quinone glucose dehydrogenase.