Modulated physical and chemical sensors

• US 20060008924A1
• Filed: 06/29/2005
• Published: 01/12/2006
• Est. Priority Date: 04/18/2002
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Inventors: Kopelman, Raoul, McNaughton, Brandon, Anker, Jeffrey, Behrend, Caleb
• Granted Patent: US 8,697,029 B2
• Time in Patent Office: Days
• US Class Current: 436/526
• CPC Class Codes: G01N 33/58 involving labelled substances G01N33/53 takes precedence
• CPC Class Codes: G01N 33/587 Nanoparticles

Abstract

The present invention relates to modulated (e.g., magnetically modulated) chemical sensors. In particular, the present invention relates to particles comprising fluorescent indicator dyes and methods of using such particles. Magnetic fields and/or Brownian motion modulate an optical property of the particle to distinguish it from background signals. The present invention thus provides improved methods of detecting a wide variety of analytes in fluids, fluid samples, cells and tissues.

Claims

1. A composition comprising a half-shell probe with arches, said probe comprising a matrix and a metal half-shell coated on the surface of said matrix;

said metal half-shell further comprising arch-shaped cusps.

2. The composition of claim 1, wherein said metal is magnetic.

3. The composition of claim 1, wherein said probes further comprise a label.

4. The composition of claim 3, wherein said label is embedded in said probes.

5. The composition of claim 3, wherein said label comprises a labeling particle, said particle attached to said probe.

6. A method of measuring rotational micro-viscosity and particle binding in a sample, comprising:

a) providing

i) a plurality of probes, said probes comprising a matrix coated with a metal half-shell;

ii) a device configured for the detection of different fluxes of light generated from said probes in different probe orientations; and

iii) a sample suspected of comprising an analyte object; and

b) contacting said sample with said probes under conditions such that said analyte object binds to said plurality of probes; and

c) detecting said different fluxes of light with said device to generate modulated probe signal and unmodulated background signal.

7. The method of claim 6, wherein said probes further comprise a labeling particle, said particle attached to said probes.

8. The method of claim 6, wherein said labeling particle is an indicator dye.

9. The method of claim 6, further comprising the step of separating said modulated signal from unmodulated background signal.

10. The method of claim 6, further comprising the step of identifying said analyte object based on change in said modulated signal.

11. The method of claim 6, wherein said sample is selected from the group consisting of the inside of a cell, a tissue, a bodily fluid, a surface, and a cellular homogenate.

12. The method of claim 6, wherein said different orientations comprises orientation in the direction of a magnetic field.

13. The method of claim 6, wherein said different orientations comprises orientation by Brownian motion.

14. The method of claim 6, wherein said analyte object is selected from the group consisting of a bacteria, a virus, a fungus, a protein, and a nucleic acid.

15. A method of producing uniform magnetic half-shell particles comprising:

a) providing

i) uniform particles;

ii) a substrate; and

iii) a device configured to vapor deposit magnetic materials onto said substrate;

b) depositing a layer of said particles onto said substrate; and

c) depositing magnetic materials onto said particles using said device.

16. The method of claim 15, wherein said plurality of particles have a coefficient of variation in particle radius of less that 20%.

17. The method of claim 15, wherein said plurality of particles have a coefficient of variation in particle radius of less that 2%.

18. The method of claim 15, wherein substrate comprises a flexible material wound onto a reel.

19. The method of claim 15, wherein said magnetic material is ferromagnetic cobalt.

20. A composition comprising uniform magnetic particles generated by the method of claim 15.