METHOD AND APPARATUS FOR COUPLING A SAMPLE PROBE WITH A SAMPLE SITE

• US 20090247840A1
• Filed: 02/26/2009
• Published: 10/01/2009
• Est. Priority Date: 03/08/2002
• Status: Active Grant

• Current Assignee: GLT Acquisition Corporation
• Original Assignee: Sensys Medical, Inc. (Sensys Medical Limited)
• Inventors: BLANK, Thomas B., ABUL-HAJ, Roxanne E.
• Granted Patent: US 8,718,738 B2
• Time in Patent Office: Days
• US Class Current: 600/310
• CPC Class Codes: A61B 2562/146 for optical coupling
• CPC Class Codes: A61B 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 takes precedence
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: G01N 21/01 Arrangements or apparatus for facilitating the optical investigation
• CPC Class Codes: G01N 21/359 using near infrared light
• CPC Class Codes: G01N 21/474 Details of optical heads therefor, e.g. using optical fibres

Abstract

The invention comprises method and apparatus for fluid delivery between a sample probe and a sample. The fluid delivery system includes: a fluid reservoir, a delivery channel, a manifold or plenum, a channel or moat, a groove, and/or a dendritic pathway to deliver a thin and distributed layer of a fluid to a sample probe head and/or to a sample site. The fluid delivery system reduces sampling errors due to mechanical tissue distortion, specular reflectance, probe placement, and/or mechanically induced sample site stress/strain associated with optical sampling of the sample.

Claims

1. An apparatus for delivering fluid to a sample site, comprising:

a fluid reservoir;

an optical probe, comprising;

a manifold, at least one channel, a probe face comprising a center, and at least one groove inset into said probe face;

means for delivering fluid from said fluid reservoir to said manifold, wherein said optical probe head encompasses said manifold,

wherein said channel comprises a first end connected to said manifold and a second end connected to said at least one groove.

2. The apparatus of claim 1, wherein said manifold comprises a surface dissipating fluid kinetic energy, said kinetic energy resulting from said means for delivering fluid.

3. The apparatus of claim 1, wherein said manifold distributes the fluid to said at least one channel.

4. The apparatus of claim 1, wherein said at least one channel circumferentially distributes the fluid about said center of said probe face.

5. The apparatus of claim 1, wherein said at least one channel comprises a cross-sectional dimension of less than about five thousandths of an inch.

6. The apparatus of claim 5, wherein said at least one groove comprises a cross-sectional dimension of less than about 0.01 inch.

7. The apparatus of claim 6, wherein said at least one groove further comprises dendritic pathways emanating radially outwardly from said at least one groove, wherein the fluid flows from said manifold, through said at least one channel, along said at least one groove, and moves by capillary action into said dendritic pathways.

8. The apparatus of claim 1, wherein the fluid moves through said sample probe head into said at least one channel to a delivery site within three millimeters of the center of said probe face.

9. The apparatus of claim 1, further comprising an optical analyzer, wherein said optical analyzer comprises said optical probe, wherein said optical probe moves less than about five millimeters relative to said analyzer to make proximate contact with the sample site during a measurement.

10. The apparatus of claim 9, further comprising an optical train starting at a tip of a collection fiber at said probe face to a detector, wherein all of said optical train moves in unison when said optical probe moves relative to said analyzer.

11. The apparatus of claim 1, wherein said optical probe further comprises:

a first optic, said first optic absorbing greater than ninety-five percent of light entering, from a source in said sample probe, said first optic in the wavelength range of about 200 nm to about 1100 nm, wherein said first optic does not contact the sample; and

a second optic, said second optic mechanically holding a tip of at least one collection fiber, wherein said second optic proximately contacts the sample during use.

12. The apparatus of claim 1, wherein said fluid comprises a refractive index of less than 1.32.

13. The apparatus of claim 1, wherein said fluid comprises a viscosity of less than about twelve centistokes.

14. The apparatus of claim 1, further comprising a force pressure sensor integrated into said optical probe.

15. A method for delivering fluid to a sample site, comprising the steps of:

providing an optical probe, said optical probe comprising;

a manifold, at least one channel, a probe face comprising a center, and at least one groove inset into said probe face;

moving fluid from a reservoir through tubing to said manifold, wherein said optical probe head encompasses said manifold,

distributing the fluid in said manifold to said at least one channel; and

distributing the fluid through said at least one channel, through said probe face, and to the sample site.

16. The method of claim 15, further comprising the step of:

providing a driving force to supply force to the fluid in said step of moving, wherein said driving force moves the fluid in said manifold at a greater flow rate than the fluid moves in said at least one channel.

17. The method of claim 16, further comprising the step of:

dissipating directional momentum of the fluid provided by said driving force in said manifold prior to the fluid entering said at least one channel.

18. The method of claim 15, wherein said manifold substantially fills with the fluid before the fluid exits said at least one channel to the sample site.

19. The method of claim 18, further comprising the step of:

distributing the fluid through said at least one channel to at least three separate exit ports on said probe face, at least one of said three exit ports located within three millimeters of said center of said probe face.

20. The method of claim 15, further comprising the step of:

fluid running along said grooves after said step of distributing the fluid through at said at least one channel.

21. The method of claim 15, wherein said at least one groove holds via adhesion forces all of the fluid delivered to said probe face for at least two seconds when said probe face comprises a downward alignment with gravity.

22. The method of claim 21, further comprising the step of:

delivering the fluid from said at least one groove to the sample site when said optical probe is not in contact with the sample site and when said optical probe is less than one hundred micrometers from the sample site.

23. The method of claim 15, further comprising the step of:

providing an analyzer, said analyzer comprising said optical probe; and

without moving said analyzer, moving said optical probe relative to said analyzer to within fifty micrometers of the sample site during use.

24. The method of claim 23, wherein said probe face does not contact the sample site during use.

25. The method of claim 15, wherein said at least one channel circumferentially distributes the fluid about said center of said probe face.

26. The method of claim 15, wherein said at least one groove further comprises dendritic pathways emanating radially outwardly from said at least one groove, wherein the fluid flows from said manifold, through said at least one channel, along said at least one groove, and moves by capillary action into said dendritic pathways.

27. The method of claim 15, wherein said fluid comprises a refractive index of less than 1.32, wherein said fluid comprises a viscosity of less than about twelve centistokes.

28. The method of claim 15, wherein a total volume of the fluid delivered to the sample site for a measurement is less than one hundred microliters.