Optically encoded particles

• US 8,765,484 B2
• Filed: 01/31/2003
• Issued: 07/01/2014
• Est. Priority Date: 02/07/2002
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Schmedake, Thomas, Cunin, Frederique, Sailor, Michael J., Link, Jamie
• Primary Examiner(s): Soderquist, Arlen
• Application Number:
  US10/503,217
• Publication Number:
  US 20050042764A1
• Time in Patent Office: 4,169 Days
• Field of Search: 436/166, 436/172, 436/56, 436/86, 436 94- 95, 436/518, 436/524, 436/527, 435/6, 435/6.11, 205/118, 205/122, 422/68.1, 422 8205- 8208
• US Class Current: 436/171
• CPC Class Codes: B05D 1/00 Processes for applying liquids or other fluent materials B05D5/00, B05D7/00 take precedence
• CPC Class Codes: B05D 2451/00 Type of carrier, type of coating (Multilayers)
• CPC Class Codes: G01N 21/31 Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry G01N21/72 takes precedence
• CPC Class Codes: G01N 21/45 using interferometric methods; using Schlieren methods
• CPC Class Codes: G06K 19/06084 the marking being based on nanoparticles or microbeads
• CPC Class Codes: G06K 19/0614 the marking being selective to wavelength, e.g. color barcode or barcodes only visible under UV or IR methods or arrangements for sensing record carriers using a selected wavelength, see G06K7/12
• CPC Class Codes: G09F 3/00 Labels, tag tickets, or similar identification or indication means medals or badges A44C3/00; making labels B31D1/02; sheets temporarily attached together B42F; labelling B65C; labels on record carriers G11B23/38, G11B23/40; Seals; Postage or like stamps
• CPC Class Codes: Y10T 436/13 Tracers or tags
• CPC Class Codes: Y10T 436/143333 Saccharide [e.g., DNA, etc.]
• CPC Class Codes: Y10T 436/144444 Glucose

Abstract

The invention concerns a particle having a code embedded in its physical structure by refractive index changes between different regions of the particle. In preferred embodiments, a thin film possesses porosity that varies in a manner to produce a code detectable in the reflectivity spectrum.

Claims

1. A freestanding optically encoded particle, comprising:

a first porous layer having a predetermined first porosity and thickness; and

a plurality of n additional porous layers having predetermined thicknesses and porosities, at least one of which has a predetermined porosity differing from said first porosity;

wherein

said predetermined porosities and thicknesses of said first porous layer and said n additional porous layers are configured to produce an interference pattern in the reflectivity spectrum having a distinct series of peaks such that the interference pattern forms an optical signature having a particular predetermined code determined by the porosities and thicknesses of said first porous layer and said n additional porous layers a receptor or targeting moiety for binding a predetermined analyte, wherein said receptor or targeting moiety is within one or more of said first porous layer and said n additional porous layers; and

wherein

the particle has a diameter of a few hundred microns or less and is freestanding separated from any substrate.

2. The particle of claim 1, wherein the particle has a diameter in the range from a few hundred nanometers to a few hundred microns.

3. The particle of claim 1, wherein said first porous layer and said n additional porous layers have a matched optical thickness, wherein optical thickness comprises the product of refractive index and layer thickness.

4. The particle of claim 1, wherein said interference pattern in the reflectivity spectrum extends beyond the visible spectrum.

5. The particle of claim 1, wherein said first porous layer and said n additional porous layers alternate periodically and form a Bragg stack.

6. The particle of claim 1, wherein said first porous layer and said n additional porous layers form a Rugate reflector.

7. The particle of claim 1, wherein said first porous layer and said n additional porous layers are formed from a semiconductor.

8. The particle of claim 7, wherein said semiconductor comprises silicon.

9. The particle of claim 1, wherein said first porous layer and said n additional porous layers are formed from an insulator.

10. A method for identification of an analyte bound to an encoded particle of claim 1, the method comprising steps of:

associating the encoded particle with the analyte;

generating an interference pattern in the reflectivity spectrum by illumination of the particle;

determining said particular predetermined code from the interference pattern;

identifying the analyte based upon said step of determining.

11. The method according to claim 10, wherein the targeting moiety is a sugar or polypeptide.

12. The method according to claim 10, further comprising a step of signaling binding of an analyte by fluorescence labeling or analyte autofluorescence.

13. A method for identification of an analyte bound to a particle of claim 1, the method comprising steps of:

associating the encoded particle with the analyte;

generating an interference pattern in the reflectivity spectrum by illumination of the particle;

determining said particular predetermined code from the interference pattern; and

identifying the analyte based upon said step of determining, wherein the receptor or targeting moiety is a sugar or polypeptide.

14. A method for identification of an analyte bound to a particle of claim 1, the method comprising steps of:

associating the encoded particle with the analyte;

generating an interference pattern in the reflectivity spectrum by illumination of the particle;

determining said particular predetermined code from the interference pattern; and

identifying the analyte based upon said step of determining, wherein the receptor or targeting moiety is a sugar or polypeptide.

15. A method for identification of an analyte bound to a particle of claim 1, the method comprising steps of:

associating the encoded particle with the analyte;

binding of an analyte by fluorescence labeling or analyte autofluorescence;

generating an interference pattern in the reflectivity spectrum by illumination of the particle;

determining said particular predetermined code from the interference pattern; and

identifying the analyte based upon said step of determining, wherein the receptor or targeting moiety is a sugar or polypeptide.

27. The particle of claim 1, wherein said predetermined thickness of said first porous layer and said predetermined thicknesses of said n additional porous comprise a plurality of thicknesses that are varied with respect to each other.

16. A freestanding encoded micron-sized porous particle having a particular predetermined code embedded in its physical porous structure by refractive index changes between different porous regions of the particle and a receptor or targeting moiety within said porous structure, wherein the physical porous structure has a plurality of layers some of which have separate predetermined mismatched optical thicknesses and the particle has a diameter of a few hundred microns or less and is freestanding separated from any substrate.

17. The encoded micron-sized particle of claim 16, wherein different regions of the particle have different thickness.

18. The particle of claim 16, wherein said receptor is a receptor for a biological analyte.

19. The particle of claim 16, wherein said receptor is a receptor for a chemical analyte.

20. The particle of claim 16, wherein said receptor is a receptor for a gaseous analyte.

21. The particle of claim 16, further comprising a fluorescence tag for assaying the particle.

22. The particle of claim 16, wherein said porous structure consists of porous silicon.

23. A method for identification of an analyte bound to a particle of claim 16, the method comprising steps of:

associating the encoded particle with the analyte;

generating an interference pattern in the reflectivity spectrum by illumination of the particle;

determining said particular predetermined code from the interference pattern; and

identifying the analyte based upon said step of determining.

24. A method for identification of an analyte bound to or a host including a particle of claim 16, the method comprising steps of:

associating the encoded particle with the analyte;

generating an interference pattern in the reflectivity spectrum by illumination of the particle;

determining said particular predetermined code from the interference pattern; and

identifying the analyte based upon said step of determining, wherein the receptor or targeting moiety is a sugar or polypeptide.

25. A method for identification of an analyte bound to a particle of claim 16, the method comprising steps of:

associating the encoded particle with the analyte;

binding of an analyte by fluorescence labeling or analyte autofluorescence;

generating an interference pattern in the reflectivity spectrum by illumination of the particle;

determining said particular predetermined code from the interference pattern; and

identifying the analyte based upon said step of determining, wherein the receptor or targeting moiety is a sugar or polypeptide.

26. An optically encoded particle consisting of:

a first porous layer having a predetermined first porosity; and

a plurality of n additional consecutive porous layers upon said first porous layer, said n additional consecutive porous layers having predetermined thicknesses and porosities and at least one of said n additional consecutive porous layers having a porosity differing from said first porosity and a receptor or targeting moiety within one or more of said first porous layer and said n additional consecutive porous layers;

wherein

said first porous layer and said n additional porous layers are configured to produce an interference pattern in the reflectivity spectrum having a distinct series of peaks such that the interference pattern forms an optical signature having a particular predetermined code determined by the porosities and thicknesses of said first porous layer and said n additional porous layers, and wherein

the particle has a diameter of a few hundred microns or less and is freestanding separated from any substrate.