Analyte sensors and methods of use
Analyte sensors for determining the concentration of an analyte in a sample. The sensors have a sample chamber having an inlet with a projection extending from an edge of the sensor for facilitating flow of sample into the sample chamber.
1. An analyte sensor for determining the concentration of an analyte in a sample, the sensor comprising a sample chamber having an inlet with a width and a protrusion extending from an edge of the sensor proximate the inlet, the protrusion having a width that is less than the inlet width,
wherein the sensor comprises a first substrate and a second substrate, a spacer between the first substrate and the second substrate, together the first substrate, second substrate and spacer defining the inlet, and wherein the protrusion is defined by the first substrate and the sensor further comprises a second protrusion defined by the second substrate.
2. The sensor of claim 1 , wherein the width is no more than about 80% of the inlet width.
3. The sensor of claim 1 , wherein the width is about 50% of the inlet width.
4. The sensor of claim 1 , wherein the protrusion has a height of at least about 0.2 mm.
5. The sensor of claim 1 , wherein the protrusion extends from a side edge of the substrate.
6. The sensor of claim 1 , wherein the protrusion extends from an end edge of the substrate.
7. The sensor of claim 1 , wherein the sample chamber has a volume of no more than about 1 microliter.
8. An analyte sensor for determining the concentration of an analyte in a sample, the sensor comprising:
a first substrate, a second substrate, and a spacer layer therebetween;
a sample chamber defined between the first substrate and the second substrate bounded by the spacer layer, the sample chamber having a first inlet and a protrusion extending from the first substrate at the first inlet and a second inlet and a second protrusion extending from the first substrate at the second inlet.
9. The sensor of claim 8 further comprising a third protrusion extending from the second substrate at the first inlet.
10. The sensor of claim 9 further comprising a fourth protrusion extending from the second substrate at the second inlet.
11. An analyte sensor for determining the concentration of an analyte in a sample, the sensor comprising:
a first substrate and a second substrate;
a first side edge, a second side edge and an end edge;
a sample chamber defined between the first substrate and the second substrate, the sample chamber extending from the first side edge to the second side edge;
a first aperture and a second aperture between the first substrate and the second substrate at the first side edge and the second side edge, respectively; and
at least one protrusion extending from either the first side edge or the second side edge, proximate the apertures.
12. The sensor of claim 11 comprising a first protrusion extending from the first side edge and a second protrusion extending from the second side edge.
13. The sensor of claim 12 , further comprising a third protrusion extending from the first side edge and a fourth protrusion extending from the second side edge, proximate the apertures.
14. The sensor of claim 13 , wherein the width of each of the protrusions is less than the width of the proximate aperture.
15. The sensor of claim 13 , wherein the width of each of the protrutions is no more than about 80% of the width of the proximate aperture.
16. The sensor of claim 13 , wherein the protrusions have a height of at least about 0.2 mm.
17. The sensor of claim 13 , wherein the protrusions are triangles extending from the substrates.
18. A method of analyzing an analyte concentration in a sample comprising:
contacting a sample with a sensor having a first substrate, a second substrate and a spacer layer therebetween and a sample chamber defined between the first substrate and the second substrate bounded by the spacer layer, the sample chamber having a first inlet and a protrusion extending from the first substrate at the first inlet and a second inlet and a second protrustion extending from the first substrate at the second inlet;
transferring the sample into a sample chamber through an inlet bounded by the substrates and the at least one protrusion; and
determining the concentration of analyte in the sample.
19. The method of claim 18 , wherein transferring comprises transferring the sample into the sample chamber through an inlet bounded by two protrusions.
20. The method according to claim 18 , wherein determining the concentration of analyte in the sample comprises employing one of coulometry, amperometry and potentiometry.
21. The method according to claim 20 , wherein determining the concentration of analyte in the sample comprises employing coulometry.
22. The method of claim 19 , wherein transferring comprises transferring no more than 1 μL of sample into the sample chamber.
23. The method according to claim 22 , wherein transferring comprises transferring no more than 0.5 μL of sample into the sample chamber.