Test sensor with multiple sampling routes

• US 9,939,401 B2
• Filed: 02/20/2014
• Issued: 04/10/2018
• Est. Priority Date: 02/20/2014
• Status: Active Grant

• Current Assignee: Changsha Sinocare, Inc.
• Original Assignee: Changsha Sinocare, Inc.
• Inventors: Cai, Xiaohua, Che, Hongli, Li, Shaobo
• Primary Examiner(s): Warden, Jill A
• Assistant Examiner(s): Tavares, Julie L
• Application Number:
  US14/184,764
• Publication Number:
  US 20150233861A1
• Time in Patent Office: 1,510 Days
• Field of Search: 20440301-40315
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52

Abstract

An improved disposable electrochemical test sensor designed to facilitate sampling of fluid samples. It has a fluid chamber having a novel extra wide sampling entrance. The chamber provides a reservoir from which a sample fluid can be drawn into the chamber through capillary action. The novel extra wide sampling entrance of the test sensor provided by the present invention can draw blood into the chamber not only from the front of the sampling entrance as usual in convenient sensors, but also from the top, bottom, left corner and right corner of the sampling entrance. Thus it allows easy targeting the samples with small volume, picking up smeared samples and it is more tolerant to users who jam the tip of the sensor into users'"'"' finger.

Claims

1. An electrochemical test sensor comprising:

a continuous base layer having a sampling end and an electric contact end, the base layer having electrodes at the sampling end, and electric contacts at the electric contact end, the electrodes being in communication with the electric contacts;

a middle layer formed of an electrically insulating material having a width approximately equal to a width of the base layer, and having a sampling end and an electric contact end, the middle layer disposed above the base layer, the middle layer forming a cutout region defined by at least a portion of a front edge being recessed from the middle layer sampling end along the width of the middle layer;

an upper layer having a sampling end and an electric contact end, the upper layer being attached to the middle layer such that the electric contact end is approximately aligned with the electric contact end of the middle layer, the sampling end of the upper layer being slightly recessed from the sampling end of the base layer, and extending beyond the recessed front edge of the middle layer;

a single fluid chamber defined on a top by the upper layer, on a bottom by the base layer, on a side by the recessed edge of the middle layer defining the cutout region, and having a sampling entrance defined by an open front opposite to the recessed edge of the middle layer, the fluid chamber sized and configured to receive a fluid by capillary action, and sized and configured to expose the electrodes of the base layer to the fluid;

wherein the recessed upper layer forms a top opening in communication with the fluid chamber;

wherein the base layer further defines a recessed notch along its height on the sampling end, the recessed notch creating a bottom opening, the notch and bottom opening providing a fluid communication with the fluid chamber from a front edge and a bottom surface of the electrochemical test sensor, the recessed notch sized and configured to provide the fluid communication via capillary action, and positioned below an area defined by the single fluid chamber so as to directly communicate with the single fluid chamber, wherein the bottom opening is configured to allow a fluid to enter the fluid chamber when the bottom surface of the electrochemical test sensor is parallel to a surface that the fluid is on; and

wherein the sampling end of the middle layer is recessed from a front edge of the upper layer sampling end and recessed from a front edge of the base layer sampling end, wherein the upper layer, middle layer, and base layer define two side openings in communication with the fluid chamber, each of the two side openings extending from the front edge corners of the sensor;

the fluid chamber having the sampling entrance to the fluid chamber defined by the open front opposite to the recessed edge of the middle layer, defined by the recessed notch of the base layer, and also defined by the two side openings wherein a combined length of the open front and the two side openings of the fluid chamber is less than a perimeter length of the middle layer front edge.

2. The electrochemical test sensor of claim 1 wherein the base is formed of two parts, a first base layer comprising the electrodes and electric contacts, and a second base layer covering a majority of the first base layer, the second part defining an cutout over each electrode, each cutout in communication with the fluid chamber, each cutout comprising a chemistry configured to react with a fluid when the fluid is within the fluid chamber.

3. The electrochemical test sensor of claim 2 wherein at least one of the chemistries is configured to measure a glucose concentration of the fluid when the fluid is within of the fluid chamber.

4. The electrochemical test sensor of claim 1 wherein the upper layer further defining a plurality of small vent openings, each of the plurality of small vent openings being sized to allow a passage of air, but small enough to prevent a passage of a bodily fluid and wherein each of the plurality of small vent holes has a diameter of approximately 0.1 mm.

5. The electrochemical test sensor of claim 1 wherein the cutout region of the middle layer is formed as a semicircle.

6. The electrochemical test sensor of claim 1 wherein the cutout region of the middle layer extends across a width of the middle layer.

7. The electrochemical test sensor of claim 1 wherein the upper layer further comprises a hydrophilic material on a surface facing the fluid chamber.

8. The electrochemical test sensor of claim 1 wherein the two side openings are configured to allow the fluid to enter the fluid chamber through one of the two side openings when the first or second side is parallel to a surface that the fluid is on.

9. An electrochemical test sensor comprising:

a continuous base layer having a sampling end and an electric contact end, the base layer having electrodes at the sampling end, and electric contacts at the electric contact end, the electrodes being in communication with the electric contacts;

a middle layer formed of an electrically insulating material having a width approximately equal to a width of the base layer, and having a sampling end and an electric contact end, the middle layer being disposed above the base layer, the middle layer forming a cutout region defined by at least a portion of a front edge being recessed from the middle layer sampling end along the width of the middle layer;

an upper layer having a sampling end and an electric contact end, the upper layer being attached to the middle layer such that the electric contact end is approximately aligned with the electric contact end of the base layer;

a single fluid chamber defined on a top by the upper layer, on a bottom by the base layer, on a side by the recessed edge of the middle layer defining the cutout region, and having a sampling entrance defined by an open front opposite to the recessed edge of the middle layer, the fluid chamber sized and configured to receive a fluid by capillary action, and sized and configured to expose the electrodes of the base layer to the fluid; and

wherein the base layer further defines a recessed notch along its height on the sampling end, the recessed notch creating a bottom opening at a front bottom edge of the test sensor, the notch and bottom opening providing a fluid communication with the fluid chamber from a front edge and a bottom surface of the electrochemical test sensor, the recessed notch sized and configured to provide the fluid communication via capillary action, and positioned below an area defined by the single fluid chamber so as to directly communicate with the single fluid chamber, wherein the bottom opening is configured to allow a fluid to enter the fluid chamber when the bottom surface of the electrochemical test sensor is parallel to a surface that the fluid is on; and

wherein the sampling end of the middle layer is recessed from a front edge of the upper layer sampling end and recessed from a front edge of the base layer sampling end, wherein the upper layer, middle layer, and base layer define two side openings in communication with the fluid chamber, the two side openings being defined by the middle layer sampling end being recessed from the front edge of the upper layer and base layer sampling ends, wherein a combined length of the open front and the two side openings of the fluid chamber is less than a perimeter length of the middle layer front edge.

10. The electrochemical test sensor of claim 9 wherein the base is formed of two parts, a first base layer comprising the electrodes and electric contacts, and a second base layer covering a majority of the first base layer, the second part defining an cutout over each electrode, each cutout in communication with the fluid chamber, each cutout comprising a chemistry configured to react with a fluid when the fluid is within the fluid chamber.

11. The electrochemical test sensor of claim 9 wherein the cutout region of the middle layer is formed as a semicircle.

12. The electrochemical test sensor of claim 9 wherein the cutout region of the middle layer extends across a width of the middle layer.

13. The electrochemical test sensor of claim 9 wherein the notch extends through both the first part and the second part of the base, the notch being semicircular.

14. An electrochemical test sensor comprising:

a continuous base layer having a sampling end and an electric contact end, the base layer being formed of two parts, a first base layer having three electrodes at the sampling end, and three electric contacts at the electric contact end, the electrodes being in communication with the electric contacts, the second base layer covering at least a portion of the first base layer, the second base layer defining a cutout over each electrode;

a middle layer formed of an electrically insulating material having a width approximately equal to a width of the base layer, and having a sampling end and an electric contact end, the middle layer disposed above to the base layer, the middle layer forming a cutout region defined by at least a portion of a front edge being recessed from the middle layer sampling end along the width of the middle layer, the cutout region being formed as a semicircle, the semicircle having a diameter slightly less than the width of the middle layer;

an upper layer having a sampling end and an electric contact end, the upper layer being attached to the middle layer such that the electric contact end is approximately aligned with the electric contact end of the middle layer, the sampling end of the upper layer being slightly recessed from the sampling end of the base layer, and extending beyond the recessed front edge of the middle layer;

a single fluid chamber defined on a top by the upper layer, on a bottom by the base layer, on a side by the recessed edge of the middle layer defining the cutout region, and having a sampling entrance defined by an open front opposite to the recessed edge of the middle layer, the fluid chamber sized and configured to receive a fluid by capillary action, and sized and configured to expose the electrodes of the base layer to the fluid;

wherein each cutout of the second base layer is in communication with the fluid chamber, each cutout of the second base layer comprising a chemistry configured to react with a fluid when the fluid is within the fluid chamber to indicate an analyte concentration;

wherein the recessed upper layer forms a top opening in communication with the fluid chamber;

the upper layer further comprising a hydrophilic material on a surface facing the fluid chamber;

wherein the base layer further defines a recessed notch extending along its entire height on the sampling end, the recessed notch creating a bottom opening at a front bottom edge of the test sensor, the notch and bottom opening providing a fluid communication with the fluid chamber from a front edge and a bottom surface of the electrochemical test sensor, the recessed notch sized and configured to provide the fluid communication via capillary action, and positioned below an area defined by the single fluid chamber so as to directly communicate with the single fluid chamber, wherein the bottom opening is configured to allow a fluid to enter the fluid chamber when the bottom surface of the electrochemical test sensor is parallel to a surface that the fluid is on;

wherein the sampling end of the middle layer is recessed from the front edge of the upper layer sampling end and recessed from a front edge of the base layer sampling end, wherein the upper layer, middle layer, and base layer define two side openings in communication with the fluid chamber, the two side openings being defined by the middle layer sampling end being recessed from the front edge of the upper layer and base layer sampling ends; and

wherein a combined length of the open front and the two side openings of the fluid chamber is less than a perimeter length of the middle layer front edge.

15. A method of taking a blood sample using the electrochemical test sensor of claim 14 comprising the steps of:

identifying a blood sample to be analyzed;

directing the sampling end of the electrochemical test sensor layers to be in contact with the identified blood sample;

receiving, by capillary action, the identified blood sample within the fluid chamber, the identified blood sample being received into the fluid chamber through at least one of the open side of the fluid chamber, the top opening, the notch of the base layer, and the two side openings; and

venting air out of the fluid chamber.