Analytical test strip with minimal fill-error sample viewing window
An electrochemical-based analytical test strip includes an electrically-insulating substrate, a patterned conductive layer disposed over the electrically-insulating substrate, a patterned insulating layer disposed over the patterned conductive layer, an enzymatic reagent layer disposed over the patterned conductive layer, a patterned adhesive layer disposed above the enzymatic reagent layer and a top layer disposed over the enzymatic reagent layer. In addition, the test strip has a sample-receiving chamber defined by the electrically-insulating substrate, the patterned conductive layer, the patterned insulating layer, the enzymatic reagent layer, the patterned adhesive layer and the top layer. The sample receiving chamber of the test strip has a working portion and a non-working portion and the top layer has a first portion and an opaque second portion. The first portion is configured such that a user can view the working portion of the sample-receiving chamber through the first portion of the top layer, while the opaque second portion is configured to preclude a user from viewing the non-working portion of the sample-receiving chamber.
1. An analytical test strip comprising:
a substrate;
an enzymatic reagent layer;
a top layer disposed over the enzymatic reagent layer, the top layer having a first portion and an opaque second portion; and
a sample receiving chamber defined within the analytical test strip, the sample receiving chamber having a working portion configured to contain only a minimal volume of sample required for operation of the analytical test strip and a non-working portion configured to contain a remaining volume of sample beyond the minimal volume required for operation of the analytical test strip;
wherein the first portion and the opaque second portion of the top layer are configured such that a user can view the complete working portion of the sample-receiving chamber through the first portion of the top layer and is precluded from viewing the non-working portion of the sample-receiving chamber by the opaque second portion of the top layer.
2. The analytical test strip of claim 1 wherein the analytical test strip is configured as a photometric analytical test strip.
3. The analytical test strip of claim 1 wherein the analytical test strip is an electrochemical-based analytical test strip and the substrate is an electrically-insulating substrate; the electrochemical-based analytical test strip further comprising:
a patterned conductive layer disposed over the electrically-insulating substrate; and
a patterned insulating layer disposed over the patterned conductive layer;
and wherein the enzymatic layer is disposed at least over at least a portion of the patterned conductive layer.
4. The electrochemical-based analytical test strip of claim 3 , wherein the top layer is an adhesive tape.
5. The electrochemical-based analytical test strip of claim 3 wherein the first portion of the top layer is transparent.
6. The electrochemical-based analytical test strip of claim 3 wherein the first portion of the top layer is translucent.
7. The electrochemical-based analytical test strip of claim 3 further including a patterned adhesive layer disposed over the enzymatic reagent layer.
8. The electrochemical-based analytical test strip of claim 3 wherein the working portion of the sample receiving chamber has a volume of approximately 0.95 micro-liters and the sample-receiving chamber has a volume of approximately 1.1 micro-liters.
9. The electrochemical-based analytical test strip of claim 3 wherein the working portion of the sample receiving chamber constitutes approximately 86 percent of the sample-receiving chamber.
10. The analytical test strip of claim 1 wherein the sample receiving chamber is configured for introduction of a whole blood sample.