System and method for fiber array spectral translator based polymorph screening

• US 7,471,389 B2
• Filed: 03/05/2007
• Issued: 12/30/2008
• Est. Priority Date: 03/03/2006
• Status: Active Grant

• Current Assignee: Chemimage Corporation
• Original Assignee: Chemimage Corporation
• Inventors: Tuschel, David, Nelson, Matthew P., Treado, Patrick J.
• Primary Examiner(s): Evans; F. L
• Application Number:
  US11/682,302
• Publication Number:
  US 20070206185A1
• Time in Patent Office: 666 Days
• Field of Search: 356/300, 356/301, 356/328
• US Class Current: 356/301
• CPC Class Codes: G01J 3/0221 the fibers defining an entry slit
• CPC Class Codes: G01J 3/2823 Imaging spectrometer
• CPC Class Codes: G01J 3/44 Raman spectrometry; Scattering spectrometry ; Fluorescence spectrometry
• CPC Class Codes: G01N 2021/6423 Spectral mapping, video display
• CPC Class Codes: G01N 2021/6484 Optical fibres
• CPC Class Codes: G01N 21/474 Details of optical heads therefor, e.g. using optical fibres
• CPC Class Codes: G01N 21/6456 Spatial resolved fluorescence measurements; Imaging
• CPC Class Codes: G01N 21/65 Raman scattering
• CPC Class Codes: G01N 2201/08 Optical fibres; light guides
• CPC Class Codes: G01N 2201/0833 Fibre array at detector, resolving

Abstract

The present disclosure describes methods and systems that combine Raman spectroscopy performed in a manner that utilizes one or more of widefield illumination, simultaneous multipoint Raman spectral acquisition, and spectral unmixing for the purpose of high throughput polymorph screening. Features of this methodology include: (a) high throughput polymorph screening to reduce crystal orientation effects on Raman spectra; (b) in-well multi-polymorph screening using increased statistical sampling; and (c) multipoint spectral sampling to enable spectral unmixing.

Claims

1. A method for polymorph screening, comprising:

illuminating a sample using widefield illumination to thereby produce scattered photons;

receiving said scattered photons substantially simultaneously from a plurality of spatial locations of said sample using a fiber array spectral translator and directing said scattered photons to a photon detector;

detecting said scattered photons and providing therefrom plural spectra of said sample; and

applying a spectral unmixing algorithm to said plural spectra to thereby determine the presence of one or more polymorphs in said sample.

2. The method of claim 1 wherein said scattered photons are Raman scattered photons.

3. The method of claim 2 wherein said spectra are Raman spectra.

4. The method of claim 1 wherein said widefield illumination comprises illuminating said sample with a laser.

5. The method of claim 1 wherein each fiber of said fiber array spectral translator receives Raman scattered photons from a different region of said sample.

6. The method of claim 5 wherein ones of said different regions overlap.

7. The method of claim 1 wherein said photon detector is selected from the group consisting of:

charge-coupled device (“

CCD”

), complementary metal oxide semiconductor (“

CMOS”

) detector, and focal plane array sensor.

8. The method of claim 1 wherein said spectral unmixing algorithm is a Spectral Mixture Resolution algorithm.

9. The method of claim 1 wherein said spectral unmixing algorithm is a Multivariate Curve Resolution algorithm.

10. The method of claim 1 wherein said sample is disposed in a well of a well plate.

11. A system for polymorph screening, comprising:

a photon source for illuminating a sample using widefield illumination to thereby produce scattered photons;

a fiber array spectral translator for receiving said scattered photons substantially simultaneously from a plurality of spatial locations of said sample and directing said scattered photons to a photon detector;

said photon detector for detecting said scattered photons and providing therefrom plural spectra of said sample; and

a microprocessor unit for applying a spectral unmixing algorithm to said plural spectra to thereby determine the presence of one or more polymorphs in said sample.

12. The system of claim 11 wherein said scattered photons are Raman scattered photons.

13. The system of claim 12 wherein said spectra are Raman spectra.

14. The system of claim 11 wherein said photon source comprises a laser.

15. The system of claim 11 wherein each fiber of said fiber array spectral translator receives Raman scattered photons from a different region of said sample.

16. The system of claim 15 wherein ones of said different regions overlap.

17. The system of claim 11 wherein said photon detector is selected from the group consisting of:

charge-coupled device (“

CCD”

), complementary metal oxide semiconductor (“

CMOS”

) detector, and focal plane array sensor.

18. The system of claim 11 wherein said spectral unmixing algorithm is a Spectral Mixture Resolution algorithm.

19. The system of claim 11 wherein said spectral unmixing algorithm is a Multivariate Curve Resolution algorithm.

20. The system of claim 11 wherein said sample is disposed in a well of a well plate.

21. The system of claim 11 wherein said microprocessor unit runs a software program for applying said spectral unmixing algorithm.

22. A method for polymorph screening, comprising:

illuminating a sample with first photons in a widefield illumination manner to thereby produce second photons, wherein said sample comprises a polymorph of a compound wherein first ones of said polymorph are disposed in a first orientation and second ones of said polymorph are disposed in a second orientation, and wherein first ones of said second photons are scattered from said first oriented polymorphs and second ones of said second photons are scattered from said second oriented polymorphs;

receiving said second photons at a proximal end of a fiber array spectral translator comprising plural fibers wherein each fiber of said fiber array spectral translator is associated with a different predetermined region of said sample;

delivering said second photons at a distal end of said fiber array spectral translator to a photon detector;

detecting said second photons and providing therefrom plural spectra comprising a first spectrum of said first oriented polymorphs and a second spectrum of said second oriented polymorphs; and

applying a spectral unmixing algorithm to said plural spectra to thereby determine a quantity of said first and second oriented polymorphs.

23. The method of claim 22 wherein said second photons are photons scattered by said sample.

24. The method of claim 23 wherein said scattered photons are Raman scattered photons.

25. The method of claim 24 wherein said plural spectra are Raman spectra.

26. The method of claim 22 wherein said widefield illumination comprises illuminating said sample with a laser.

27. The method of claim 22 wherein each fiber of said fiber array spectral translator receives Raman scattered photons from a different region of said sample.

28. The method of claim 27 wherein ones of said different regions overlap.

29. The method of claim 22 wherein said photon detector is selected from the group consisting of:

charge-coupled device (“

CCD”

), complementary metal oxide semiconductor (“

CMOS”

) detector, and focal plane array sensor.

30. The method of claim 22 wherein said spectral unmixing algorithm is a Spectral Mixture Resolution algorithm.

31. The method of claim 22 wherein said spectral unmixing algorithm is a Multivariate Curve Resolution algorithm.

32. The method of claim 22 wherein said sample is disposed in a well of a well plate.

33. A system for polymorph screening, comprising:

a photon source for illuminating a sample with first photons in a widefield illumination manner to thereby produce second photons, wherein said sample comprises a polymorph of a compound wherein first ones of said polymorph are disposed in a first orientation and second ones of said polymorph are disposed in a second orientation, and wherein first ones of said second photons are scattered from said first oriented polymorphs and second ones of said second photons are scattered from said second oriented polymorphs;

a fiber array spectral translator comprising plural fibers for receiving said second photons at a proximal end wherein each fiber of said fiber array spectral translator is associated with a different predetermined region of said sample, and for delivering said second photons at a distal end to a photon detector;

said photon detector for detecting said second photons and providing therefrom plural spectra comprising a first spectrum of said first oriented polymorphs and a second spectrum of said second oriented polymorphs; and

a microprocessor unit for applying a spectral unmixing algorithm to said plural spectra to thereby determine a quantity of said first and second oriented polymorphs.

34. The system of claim 33 wherein said second photons are photons scattered by said sample.

35. The system of claim 34 wherein said scattered photons are Raman scattered photons.

36. The system of claim 35 wherein said plural spectra are Raman spectra.

37. The system of claim 33 wherein said widefield illumination comprises illuminating said sample with a laser.

38. The system of claim 33 wherein each fiber of said fiber array spectral translator receives Raman scattered photons from a different region of said sample.

39. The system of claim 38 wherein ones of said different regions overlap.

40. The system of claim 33 wherein said photon detector is selected from the group consisting of:

charge-coupled device (“

CCD”

), complementary metal oxide semiconductor (“

CMOS”

) detector, and focal plane array sensor.

41. The system of claim 33 wherein said spectral unmixing algorithm is a Spectral Mixture Resolution algorithm.

42. The system of claim 33 wherein said spectral unmixing algorithm is a Multivariate Curve Resolution algorithm.

43. The system of claim 33 wherein said sample is disposed in a well of a well plate.

44. The system of claim 33 wherein said microprocessor unit runs a software program for applying said spectral unmixing algorithm.

45. A method for polymorph screening, comprising:

illuminating a sample with first photons in a widefield illumination manner to thereby produce second photons, wherein said sample comprises a plurality of polymorphs of a compound wherein first ones of said second photons are scattered from a first polymorph and second ones of said second photons are scattered from a second polymorph;

receiving said second photons at a proximal end of a fiber array spectral translator comprising plural fibers wherein each fiber of said fiber array spectral translator is associated with a different predetermined region of said sample;

delivering said second photons at a distal end of said fiber array spectral translator to a photon detector;

detecting said second photons and providing therefrom plural spectra comprising a first spectrum of said first polymorph and a second spectrum of said second polymorph; and

applying a spectral unmixing algorithm to said plural spectra to thereby determine a quantity of each of said first and second polymorphs.

46. The method of claim 45 wherein said second photons are photons scattered by said sample.

47. The method of claim 46 wherein said scattered photons are Raman scattered photons.

48. The method of claim 47 wherein said plural spectra are Raman spectra.

49. The method of claim 45 wherein said widefield illumination comprises illuminating said sample with a laser.

50. The method of claim 45 wherein each fiber of said fiber array spectral translator receives Raman scattered photons from a different region of said sample.

51. The method of claim 50 wherein ones of said different regions overlap.

52. The method of claim 45 wherein said photon detector is selected from the group consisting of:

charge-coupled device (“

CCD”

), complementary metal oxide semiconductor (“

CMOS”

) detector, and focal plane array sensor.

53. The method of claim 45 wherein said spectral unmixing algorithm is a Spectral Mixture Resolution algorithm.

54. The method of claim 45 wherein said spectral unmixing algorithm is a Multivariate Curve Resolution algorithm.

55. The method of claim 45 wherein first ones of said first polymorph are disposed in a first orientation and second ones of said first polymorph are disposed in a second orientation.

56. The method of claim 55 wherein a first subset of said first ones of said second photons are scattered from said first oriented polymorphs and a second subset of said first ones of said second photons are scattered from said second oriented polymorphs.

57. The method of claim 56 wherein said first spectrum comprises a third spectrum from said first oriented polymorphs and a fourth spectrum from said second oriented first polymorphs.

58. The method of claim 57 wherein applying said spectral unmixing algorithm includes determining a quantity of said first oriented polymorphs and a quantity of said second oriented polymorphs.

59. A system for polymorph screening, comprising:

a photon source for illuminating a sample with first photons in a widefield illumination manner to thereby produce second photons, wherein said sample comprises a plurality of polymorphs of a compound wherein first ones of said second photons are scattered from a first polymorph and second ones of said second photons are scattered from a second polymorph;

a fiber array spectral translator comprising plural fibers for receiving said second photons at a proximal end wherein each fiber of said fiber array spectral translator is associated with a different predetermined region of said sample, and for delivering said second photons at a distal end to a photon detector;

said photon detector for detecting said second photons and providing therefrom plural spectra comprising a first spectrum of said first polymorph and a second spectrum of said second polymorph; and

a microprocessor unit for applying a spectral unmixing algorithm to said plural spectra to thereby determine a quantity of each of said first and second polymorphs.

60. The system of claim 59 wherein said second photons are photons scattered by said sample.

61. The system of claim 60 wherein said scattered photons are Raman scattered photons.

62. The system of claim 61 wherein said plural spectra are Raman spectra.

63. The system of claim 59 wherein said widefield illumination comprises illuminating said sample with a laser.

64. The system of claim 59 wherein each fiber of said fiber array spectral translator receives Raman scattered photons from a different region of said sample.

65. The system of claim 64 wherein ones of said different regions overlap.

66. The system of claim 59 wherein said photon detector is selected from the group consisting of:

charge-coupled device (“

CCD”

), complementary metal oxide semiconductor (“

CMOS”

) detector, and focal plane array sensor.

67. The system of claim 59 wherein said spectral unmixing algorithm is a Spectral Mixture Resolution algorithm.

68. The system of claim 59 wherein said spectral unmixing algorithm is a Multivariate Curve Resolution algorithm.

69. The system of claim 59 wherein said microprocessor unit runs a software program for applying said spectral unmixing algorithm.

70. The system of claim 59 wherein first ones of said first polymorph are disposed in a first orientation and second ones of said first polymorph are disposed in a second orientation.

71. The system of claim 70 wherein a first subset of said first ones of said second photons are scattered from said first oriented polymorphs and a second subset of said first ones of said second photons are scattered from said second oriented polymorphs.

72. The system of claim 71 wherein said first spectrum comprises a third spectrum from said first oriented polymorphs and a fourth spectrum from said second oriented polymorphs.

73. The system of claim 72 wherein said microprocessor unit applies said spectral unmixing algorithm to determine a quantity of said first oriented polymorphs and a quantity of said second oriented polymorphs.