In vitro point-of-care sensor and method of use

• US 8,790,591 B2
• Filed: 07/11/2011
• Issued: 07/29/2014
• Est. Priority Date: 07/09/2010
• Status: Active Grant

• Current Assignee: Case Western Reserve University
• Original Assignee: Case Western Reserve University
• Inventors: Peshkova, Maria, Krikorian, Armand, Nair, Sumitha, Ahuja, Punkaj, Gratzl, Miklos
• Primary Examiner(s): MERKLING, SALLY ANNE
• Application Number:
  US13/809,318
• Publication Number:
  US 20130109040A1
• Time in Patent Office: 1,114 Days
• Field of Search: 422/430
• US Class Current: 422/430
• CPC Class Codes: G01N 2021/775 Indicator and selective membrane
• CPC Class Codes: G01N 2021/7759 Dipstick; Test strip
• CPC Class Codes: G01N 2021/7786 Fluorescence
• CPC Class Codes: G01N 21/78 producing a change of colour
• CPC Class Codes: G01N 21/80 Indicating pH value
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings

Abstract

An in vitro sensor for point-of-care detection of at least one analyte or reaction product includes an inert, impermeable substrate, a sensing system, and a reference system. The substrate includes a first transparent surface oppositely disposed from a second surface and first and second cavities. Each of the first and second cavities defines an opening at the second surface. The sensing system is disposed in at least a portion of the first cavity and includes an analyte-detection optode membrane, an analyte-permeable membrane, and a plurality of non-transparent microbeads associated with at least one of the analyte-detection optode membrane and the analyte-permeable membrane. The analyte-permeable membrane is layered upon the analyte-detection optode membrane and covers the opening of the first cavity. The reference system is disposed in at least a portion of the second cavity.

Claims

1. An in vitro sensor for point-of-care (POC) detection of at least one analyte or reaction product, said sensor comprising:

an inert, impermeable substrate including a first transparent surface oppositely disposed from a second surface and first and second cavities, each of said first and second cavities defining an opening at said second surface;

a sensing system disposed in at least a portion of said first cavity, said sensing system comprising an analyte-detection optode membrane, an analyte-permeable membrane, and a plurality of non-transparent microbeads associated with at least one of said analyte-detection optode membrane and said analyte-permeable membrane, said analyte-permeable membrane being layered upon said analyte-detection optode membrane and covering said opening of said first cavity; and

a reference system disposed in at least a portion of said second cavity.

2. The sensor of claim 1, wherein at least a portion of said substrate is formed from one or more of polymethylmetacrylate, 2-hydroxyethyl methacrylate, and glass.

3. The sensor of claim 1, wherein at least a portion of said substrate is darkened.

4. The sensor of claim 1, wherein said opening of said at least one cavity has a diameter of about 1 mm and a depth of about 300 μ

m.

5. The sensor of claim 1, wherein said analyte-detection optode membrane includes at least one indicator material that undergoes a color change in response to the analyte or reaction product.

6. The sensor of claim 5, wherein said analyte-detection optode membrane includes at least one detection material.

7. The sensor of claim 1, wherein said analyte-permeable membrane is transparent.

8. The sensor of claim 1, wherein said analyte-permeable membrane is permeable to select molecules.

9. The sensor of claim 8, wherein said analyte-permeable membrane excludes at least one of anions, lipids and proteins.

10. The sensor of claim 1, wherein said analyte-permeable membrane has a multi-layered comprising:

an outermost layer that is in contact with a biological fluid sample;

a middle layer for regulating and limiting the diffusion of molecules into said at least one cavity; and

a negatively-charged inner layer that is in contact with said analyte-detection optode membrane.

11. The sensor of claim 1, wherein said plurality of non-transparent microbeads is dispersed within at least one of said analyte-detection optode membrane and said analyte-permeable membrane.

12. The sensor of claim 1, wherein said plurality of non-transparent microbeads comprises a layer disposed between said analyte-detection optode membrane and said analyte-permeable membrane.

13. A method for detecting at least one analyte or reaction product in a biological fluid sample taken from a subject at a POC, said method comprising the steps of:

providing an in vitro sensor comprising a substrate having first and second cavities, a sensing system at least partially disposed in the first cavity, and a reference system at least partially disposed in the second cavity, the sensing system comprising an analyte-detection optode membrane, an analyte-permeable membrane, and a plurality of non-transparent microbeads associated with at least one of the analyte-detection optode membrane and the analyte-permeable membrane, the analyte-permeable membrane being layered upon the analyte-detection optode membrane and covering the opening of the first cavity;

obtaining the biological fluid sample from the subject;

contacting the biological fluid sample with at least a portion of the analyte-permeable membrane; and

detecting a color change within the sensing system.

14. The method of claim 13, wherein said contacting step further comprises the steps of:

providing a sample container configured to accommodate the sensor;

placing the biological fluid sample in the sample container; and

placing the sensor in the sample container so that the biological fluid sample contacts the at least a portion of the analyte-permeable membrane.

15. The method of claim 13, wherein said detecting step further comprises the step of using a charge-coupled device to detect the color change.

16. The method of claim 15 further comprising the step of transforming the detected color change into a quantitative reading.

17. The method of claim 13, the POC being a critical care environment.

18. The method of claim 17, the critical care environment being an intensive care unit.