LOW COST ELECTROCHEMICAL DISPOSABLE SENSOR FOR MEASURING GLYCATED HEMOGLOBIN

• US 20120261257A1
• Filed: 04/18/2012
• Published: 10/18/2012
• Est. Priority Date: 04/18/2011
• Status: Active Grant

• Current Assignee: Indian Institute of Science
• Original Assignee: Indian Institute of Science
• Inventors: Bhat, Navakanta, Amrutur, Bharadwaj, Vanjari, Siva Rama Krishna, Srinivasan, Sampath, Kalapu, Chakrapani, Mandal, Amit Kumar
• Granted Patent: US 8,702,931 B2
• Time in Patent Office: Days
• US Class Current: 204/403.06
• CPC Class Codes: A61B 5/1468 using chemical or electrochemical methods, e.g. by polarographic means A61B5/1486 takes precedence
• CPC Class Codes: C07F 5/02 Boron compounds
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52
• CPC Class Codes: G01N 27/3275 Sensing specific biomolecules, e.g. nucleic acid strands, based on an electrode surface reaction

Abstract

Design of a disposable screen printed electrode (SPE) for sensing percentage glycated hemoglobin using electrochemistry is disclosed. SPE has four electrodes, one working electrode for the detection of glycated hemoglobin, one working electrode for the detection of hemoglobin and the other two electrodes are counter and reference electrodes that are common for both detection schemes. It also has a cellulose acetate membrane with lysis agents and surfactant embedded in it. Lysis agents lyse erythrocytes and release hemoglobin. Surfactants modify hemoglobin structure and enhance the rate the electron transfer and thereby the output signal during the electrochemical analysis. The SPE is low cost and user friendly. The only input from the user is a drop of blood.

Claims

1. A sensor for measuring percentage glycated hemoglobin (GHb) and total hemoglobin (Hb) using a first working electrode and a second working electrode, said sensor further comprising a reference electrode for maintaining potential and a counter electrode for providing charge balance, said sensor having salts and surfactant-embedded membranes for lysing erythrocytes of blood cell samples and releasing hemoglobin molecules and wherein said sensor has enhanced output signal intensity.

2. The sensor of claim 1, wherein said electrodes are screen printed electrodes.

3. The sensor of claim 1, wherein said membrane is a porous asymmetric cellulose acetate membrane.

4. The sensor of claim 1, wherein said porous membrane comprises a dense top layer and an open porous sub layer.

5. The sensor of claim 1, wherein said porous membrane comprises cellulose acetate membrane modified with lysing agents and surfactants.

6. The sensor of claim 1, wherein said pores in the dense top layer allow hemoglobin and plasma to pass through.

7. The sensor of claim 1, wherein said membrane is attached on top of the electrode such that the porous sub layer faces the air and the dense porous layer faces the electrode.

8. The sensor of claim 1, wherein the membrane is a nylon membrane modified with lysing agents and surfactants.

9. The sensor of claim 1, wherein the membrane is a porous polymeric membrane modified with lysing agents and surfactants.

10. The sensor of claim 1, wherein said reference electrode and said counter electrodes have shapes selected from circles, squares, hexagons and pentagons around said working electrodes.

15. The sensor of claim 1, wherein said sensor is a bufferless sensor.

11. A method for the chemical modification of graphene oxide with amino phenyl boronic acid comprising reacting GO (graphene oxide) with ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) in the presence of deionised water.

12. A composite formed by the reaction of Graphene Oxide with 3-Aminophenylboronic acid, said composite used to coat an electrode, said electrode used to measure GHb.

13. An electrode coated by the composite of claim 12 for detecting GHb.

14. A sensor for measuring percentage glycated hemoglobin (GHb) and total hemoglobin (Hb) using a first working electrode and a second working electrode, said sensor further comprising a reference electrode for maintaining potential and a counter electrode for providing charge balance, said sensor having salts and surfactant embedded membranes for lysing erythrocytes of blood cell samples and releasing hemoglobin molecules and wherein said first working electrode being a GO-APBA coated electrode, said second working electrode being a GO-surfactant coated electrode.

16-22. -22. (canceled)