Electrode layout for blood test sensor strip

• US 8,945,023 B2
• Filed: 05/22/2014
• Issued: 02/03/2015
• Est. Priority Date: 01/19/2010
• Status: Active Grant

• Current Assignee: Embecta Corporation
• Original Assignee: Becton, Dickinson & Co
• Inventors: Mondro, Jason, Schiff, David, Gisler, Scott W.
• Primary Examiner(s): EISEMAN, ADAM JARED
• Application Number:
  US14/284,922
• Publication Number:
  US 20140251837A1
• Time in Patent Office: 257 Days
• Field of Search: 600/573, 600/575, 600/583, 600/584, 606/181, 606/182, 204/400, 204/403.01, 204/403.02, 204/403.03
• US Class Current: 600/583
• CPC Class Codes: A61B 2562/0295 Strip shaped analyte sensors for apparatus classified in A61B5/145 or A61B5/157
• CPC Class Codes: A61B 2562/046 in a matrix array
• CPC Class Codes: A61B 2562/125 characterised by the manufacture of electrodes
• CPC Class Codes: A61B 5/1411 by percutaneous method, e.g. by lancet
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1477 non-invasive
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150213 Venting means
• CPC Class Codes: A61B 5/150358 Strips for collecting blood, e.g. absorbent optical reagent test strips G01N21/8483; chemical reagent test strips G01N33/4875, G01N33/52
• CPC Class Codes: A61B 5/150412 Pointed piercing elements, e.g. needles, lancets for piercing the skin blade-like piercing elements A61B5/150442
• CPC Class Codes: A61B 5/150503 Single-ended needles hollow piercing element tip design A61B5/150396, needle sets for catheters A61M25/06, needles for bringing media into the body A61M5/32
• CPC Class Codes: A61B 5/1519 comprising driving means, e.g. a spring, for propelling the piercing unit
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: G01N 27/3271 Amperometric enzyme electrodes for analytes in body fluids, e.g. glucose in blood amperometry per se G01N27/49; aspects concerning the enzyme reagent C12Q1/001
• 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 electrode layout for a continuous strip sensor is provided which reduces misalignment of the electrodes with the contacts which read the position of the strip. Better contact with the electrodes reduces or eliminates transient signals between stop positions of the sensor strip.

Claims

1. A method for performing a plurality of blood sample acquisition and testing procedures on a strip

having a plurality of test sites arranged in series in a travel direction on the strip, wherein each test site includes a lancet hole, first electrodes for producing a first signal when a sufficient volume of a blood sample is detected, second electrodes for obtaining a second signal characteristic of the blood sample, and a plurality of conductive pads that are aligned in a matrix of rows and columns and are aligned to make electrical contact with device contacts on a blood test sensor device, wherein the conductive pads for the first electrodes are electrically connected thereto by respective conductive traces, wherein the conductive pads for the second electrodes are electrically thereto by respective conductive traces, and wherein a leading edge in the travel direction of a first conductive pad in a row is in front of a leading edge in the travel direction of a second conductive pad in the same row, comprising the steps of:

injecting a lancet through the lancet hole at a first test site into a subject to obtain the blood sample;

contacting the blood sample with the first electrodes;

advancing the strip in response to the first signal produced by the first electrodes;

contacting the blood sample with the second electrodes to obtain the second signal; and

advancing the strip to a second test site.

2. The method according to claim 1, wherein:

at least three separate rows of conductive pads correspond to at least a lancing step position, a blood volume detection step position, and a blood characteristic sensing step position of the strip in a lancing/sensing process;

at least four columns of conductive pads are aligned with respective device contacts; and

at least two of the conductive pads in each said row are grounded at each of said positions in the lancing/sensing process.

3. The method according to claim 2, further comprising the step of

producing a signal corresponding to a home position when electrical contact is made with conductive pads in a fourth row.

4. The method according to claim 1, further comprising the step of detecting the pressure of the strip against the subject prior to injecting the lancet into the subject.

5. The method according to claim 1, further comprising the step of obtaining the first signal when a blood droplet bridges a pair of first electrodes causing them to short.

6. The method according to claim 1, further comprising the step of passing current through the blood sample to obtain the second signal.

7. The method according to claim 1, wherein a non-conductive cover layer is provided over the conductive traces.

8. The method according to claim 6, wherein the second signal corresponds to an electrochemical measurement of blood glucose.

9. The method according to claim 7, wherein the non-conductive cover layer has a window to expose the conductive pads to the device contacts.