ANALYTE SENSOR METHOD AND APPARATUS

• US 20080119701A1
• Filed: 11/05/2007
• Published: 05/22/2008
• Est. Priority Date: 11/03/2006
• Status: Active Grant

• Current Assignee: Volcano Corporation (Koninklijke Philips N.V.)
• Original Assignee: CardioSpectra, Inc. (Koninklijke Philips N.V.)
• Inventors: Milner, Thomas E., Kemp, Nathaniel J., Castella, Paul
• Granted Patent: US 8,280,470 B2
• Time in Patent Office: Days
• US Class Current: 600/342
• CPC Class Codes: A61B 2562/0285 Nanoscale sensors
• CPC Class Codes: A61B 2562/12 Manufacturing methods specially adapted for producing sensors for in-vivo measurements
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 takes precedence
• CPC Class Codes: G01N 21/4795 spatially resolved investigating of object in scattering medium in vivo A61B

Abstract

Provided herein are systems, methods, and apparatuses for an analyte sensor.

Claims

1. An analyte sensing device comprising:

a. a sensor body member including at least one nanopore;

b. an optical conduit in optical communication with the sensor body member and the nanopore, wherein the optical conduit transmits and receives optical energy from the sensor body member; and

c. a photodetector optically coupled to the optical conduit to determine an optical parameter from the sensor body member.

2. The analyte sensing device of claim 1, wherein the sensor body member includes a reflective surface in optical communication with the optical conduit and the optical conduit includes a reflective surface.

3. The analyte sensing device of claim 2, wherein the photodetector is optically coupled to an optical coherence tomography instrument.

4. The analyte sensing device of claim 3, wherein the optical coherence tomography instrument comprises:

a. a light source;

b. a polarization maintaining reference path;

c. a polarization maintaining sample path optically aligned with a collimating lens, a variable wave retarder, and the optical conduit;

d. a polarization maintaining detection path optically aligned with the photodetector, wherein the detection path, the source path, and the reference path are each optically connected to a path coupler.

5. The analyte sensing device of claim 4, wherein the nanopore is at least 300 nanometers.

6. The analyte sensing device of claim 4, wherein the optical coherence tomography instrument is phase sensitive to measure the change in optical path length and determine the refractive index of the analyte.

7. The analyte sensing device of claim 4, wherein the optical coherence tomography instrument is polarization sensitive and the nanopores are asymmetrical to measure the form-birefringence and determine the refractive index of the analyte within the nanopore.

8. The analyte sensing device of claim 4, wherein the sensor body element is optically coupled with at least one faraday rotator and the optical coherence tomography instrument is polarization sensitive to measure circular birefringence.

9. The analyte sensing device of claim 4, wherein the optical coherence tomography is phase and polarization sensitive and the nanopores are asymmetrical.

10. The analyte sensing device of claim 3, wherein the sensor body member is operationally coupled to a catheter.

11. The analyte sensing device of claim 3, wherein the nanopores are substantially parallel to one another.

12. The analyte sensing device of claim 3, wherein sensor body member is substantially coated with a surfactant.

13. The analyte sensing device of claim 3, wherein an optical pathlength of the light reflected from the nanopores and a polarization state of light reflected from the nanopores determines the analyte concentration in the nanopores.

14. A method for obtaining optical measurements of an analyte comprising the steps of:

optically coupling a sensor body element with an optical conduit, where the sensor body element includes at least one nanopore and a reflective surface at the distal end of the sensor body element, and the optical conduit includes a reflective surface at the distal end of the optical conduit;

permitting the diffusion of an analyte into the nanopore;

transmitting optical energy to the sensor body element; and

measuring an optical parameter with a detector.

15. The method for obtaining optical measurements of an analyte of claim 14, wherein measuring optical parameter is by an optical coherence tomography instrument comprising:

generating light energy from a light source;

transmitting at least a first portion of the generated light energy onto a reference reflector wherein at least a portion of the transmitted first portion of light energy is reflected by the reference reflector;

transmitting at least a second portion of the generated light energy into the sensor body, wherein at least a portion of the transmitted second portion of light energy contacts an analyte located within the nanopore and wherein at least a portion of the light energy which contacts the analyte is reflected;

receiving the light energy reflected by the reference reflector and the analyte;

combining the received light energy, wherein the combined light energy interferes; and

processing the combined light energy to measure the refractive index of the analyte within the pore.

16. The method for obtaining optical measurements of an analyte of claim 14 further comprises measuring the change in optical pathlength to measure a refractive index of the analyte inside the nanopores where the optical coherence tomography instrument is phase sensitive and coupled to an optical clock.

17. The method for obtaining optical measurements of an analyte of claim 14 further comprises measuring a change in form-birefringence to measure an average refractive index of the analyte inside the nanopores where the optical coherence tomography instrument is polarization sensitive and the nanopores are asymmetrical.

18. The method for obtaining optical measurements of an analyte of claim 16 further comprising measuring a polarization state of the light backscattered from the sensor body element;

depicting a trajectory of the polarization state on a Poincare sphere or a complex polarization ratio (Z) plane; and

analyzing the trajectory to estimate the analyte concentration in the nanopore.

19. The method for obtaining optical measurements of an analyte of claim 15 further comprises:

detecting a phase retardation between the orthogonal light oscillations in the sensing body element;

breaking the symmetry due to reflection of light in the sensing body element with at least one Faraday rotator element;

analyzing the trajectory of a Stokes vector on a Poincare sphere corresponding to the light backscattered from the sensing body element for movements orthogonal to displacements due to the linear birefringence;

analyzing the composite trajectory on the Poincare sphere with movements due to linear form birefringence and circular birefringence of the analyte to estimate analyte concentration.

20. The method for obtaining optical measurements of an analyte of claim 15 further comprising estimating the concentration of the analyte with circular birefringence where the optical coherence tomography instrument is polarization sensitive and the sensor body element is coupled to at least on Faraday rotation element.

21. The method for obtaining optical measurements of an analyte of claim 15 further comprising estimating the analyte concentration with circular and form birefringence where the optical coherence tomography instrument is phase and polarization sensitive and the sensor body element is coupled to at least one Faraday rotation element.

22. The method for obtaining optical measurements of an analyte of claim 15 further comprising coupling the sensor body element with a catheter and inserting the catheter into a patient.

23. The method for obtaining optical measurements of an analyte of claim 15, further comprising allowing the analyte to fill the sensor body element;

monitoring the analyte by optical parameters in a time-dependent manner; and

deducing the concentration of the analyte from the time variation of the analyte filling the sensor body element.