Optical sensor containing particles for in situ measurement of analytes

• US 7,228,159 B2
• Filed: 06/27/2002
• Issued: 06/05/2007
• Est. Priority Date: 07/10/2001
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Precisense A/S (Medtronic Plc)
• Inventors: Kristensen, Jesper, Petersson, Bo
• Primary Examiner(s): WINAKUR, ERIC FRANK
• Application Number:
  US10/483,426
• Publication Number:
  US 20040199062A1
• Time in Patent Office: 1,804 Days
• Field of Search: 600/310, 600/312, 600/316, 600/317, 600/322
• US Class Current: 600/316
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14735 comprising an immobilised reagent
• CPC Class Codes: A61B 5/415 the glands, e.g. tonsils, adenoids or thymus
• CPC Class Codes: A61B 5/417 the bone marrow
• CPC Class Codes: A61B 5/418 lymph vessels, ducts or nodes
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings

Abstract

The invention relates to a sensor for the in vivo measurement of an analyte, comprising a plurality of particles of suitable size such that when implanted in the body of a mammal the particles can be ingested by macrophages and transported away from the site of implantation, each particle containing the components of an assay having a readout which is an optical signal detectable transdermally by external optical means, and either each particles being contained within a biodegradable material preventing ingestion by the macrophages, or each particle being non-biodegradable. The invention relates to a process for the detection of an analyte using such a sensor, comprising implantation of the sensor into the skin of a mammal, transdermal detection of analyte using external optical means, degradation of the biodegradable material, ingestion of the particles by macrophages, and removal of the particles from the site of implantation by macrophages.

Claims

1. A sensor for in vivo measurement of an analyte, comprising a plurality of particles having a size such that when implanted in a body of a mammal at an implantation site the particles can be ingested by macrophages and transported away from the implantation site, wherein each particle of the sensor contains the components of an assay having a readout which is an optical signal detectable transdermally by external optical means, and wherein the particles are each contained within a biodegradable material preventing ingestion by the macrophages.

2. A sensor as claimed in claim 1, wherein the particles are less than 5 μ

m in their largest dimension.

3. A sensor as claimed in claim 1, wherein the assay is a binding assay.

4. A sensor as claimed in claim 3, wherein the binding assay is a competitive binding assay, the components of which include an analyte binding agent and an analyte analogue.

5. A sensor as claimed in claim 4, wherein the analyte analogue is labelled with a first chromophore and the analyte binding agent is labelled with a second chromophore, an emission spectrum of the first chromophore or the second chromophore overlapping with an absorption spectrum of the second chromophore or the first chromophore respectively.

6. A sensor as claimed in claim 4, wherein the binding agent is an antibody, a Fab fragment, a lectin, a hormone receptor, a drug receptor, an aptamer or a molecularly-imprinted polymer.

7. A sensor as claimed in claim 1, wherein the optical signal is generated by fluorescence resonance energy transfer, fluorescence polarisation, fluorescence quenching, phosphorescence, luminescence enhancement, luminescence quenching, diffraction or plasmon resonance.

8. A sensor as claimed in claim 1, wherein the analyte is glucose.

9. A sensor as claimed in claim 1, wherein the optical signal is quantitatively measurable.

10. A process for the detection of an analyte using a sensor as claimed in claim 1, comprising the steps of:

implanting the sensor into skin of a mammal at an implantation site, and

transdermally detecting analyte using external optical means,

where implantation is followed by degradation of the biodegradable material, ingestion of the particles by macrophages, and removal of the particles from the implantation site.

11. A sensor for in vivo measurement of an analyte, comprising a plurality of particles having a size such that when implanted in a body of a mammal at an implantation site the particles can be ingested by macrophages and transported away from the implantation site, wherein each particle of the sensor contains the components of an assay having a readout which is an optical signal detectable transdermally by external optical means, and wherein the particles are each contained within a biodegradable material preventing ingestion by the macrophages, the biodegradable material being a gel.