PHOTONIC BIOSNESOR ARRAYS

• US 20100167946A1
• Filed: 03/19/2008
• Published: 07/01/2010
• Est. Priority Date: 03/23/2007
• Status: Active Grant

• Current Assignee: Attomarker Limited
• Original Assignee: Attomarker Limited
• Inventors: Shaw, Andrew Mark, Olkhov, Rouslan Vladamir, Barnes, William Leslie
• Granted Patent: US 8,389,299 B2
• Time in Patent Office: Days
• US Class Current: 506/9
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G01N 21/211 Ellipsometry optical thickness measurement G01B11/06
• CPC Class Codes: G01N 21/253 for batch operation, i.e. multisample apparatus analytical automats G01N35/00
• CPC Class Codes: G01N 21/554 detecting the surface plasmon resonance of nanostructured metals, e.g. localised surface plasmon resonance
• CPC Class Codes: G01N 33/54313 the carrier being characterised by its particulate form
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings
• CPC Class Codes: G01N 33/553 Metal or metal coated
• CPC Class Codes: Y10T 436/25 including sample preparation

Abstract

This invention relates to photonic biosensor arrays in particular employing plasmon resonance based sensing, and to methods and apparatus for reading such arrays. A biosensor array for plasmon resonance-based sensing of a plurality of different biological targets simultaneously, the array comprising a transparent substrate having a surface bearing a plurality of assay spots for plasmon resonance sensing, each of said assay spots comprising a discrete metallic island, a said metallic island comprising a plurality of metallic nanoparticles to which are attached functionalising molecules for binding to a said biological target, different said islands bearing different said functionalising molecules for binding to different ones of said biological targets, and wherein total internal reflection of light at said surface at a wavelength at or near a said plasmon resonance results in scattering of said light away from said surface, said scattering being modulated by said binding of said biological targets.

Claims

1-40. -40. (canceled)

41. A biosensor array for Plasmon resonance-based sensing of a plurality of different biological targets simultaneously, the array comprising a transparent substrate having a surface bearing a plurality of assay spots for Plasmon resonance sensing, each of said assay spots comprising a discrete metallic island, a said metallic island comprising a plurality of metallic nanoparticles to which are attached functionalising molecules for binding to a said biological target, different said islands being different said functionalising molecules for binding to different ones of said biological targets, and wherein total internal reflection of light at said surface at a wavelength at or near a said plasmon resonance results in scattering of said light away from said surface, said scattering being modulated by said binding of said biological targets.

57. A biosensor array as claimed in claim 41, wherein an apparatus for reading a plasmon resonance sensing array for plasmon resonance-based sensing of a plurality of different biological targets, the array comprising a transparent substrate having a surface bearing a plurality of assay spots for plasmon resonance sensing, each of said assay spots comprising a discrete metallic island to which is attached functionalising molecules for binding to a said biological target, different said islands bearing different said functionalising molecules for binding to different ones of said biological targets, and wherein total internal reflection of light at said surface at a wavelength at or near a said plasmon resonance results in scattering of said light away from said surface, said scattering being modulated by said binding of said biological targets, the apparatus comprising:

a light source to generate light at two different substantially monochromatic wavelengths;

an optical coupling device to couple light from said light source into said sensing array;

an imaging system to image light from said array at said two different wavelengths scattered by plasmon resonance in said metallic islands, and to generate image date; and

an image analysis system coupled to said imaging system to receive said image data and to analyse said plasmon-resonance scattered light to determine levels of said different biological targets attached to said array.

59. Apparatus for reading a plasmon resonance sensing array for plasmon resonance-based sensing of a plurality of different biological targets, the array comprising a transparent substrate having a surface being a plurality of assay spots for said plasmon resonance testing, the apparatus comprising:

a light source to generate polarised light;

a polarisation modulator to modulate a polarisation f said polarised light;

an optical system to illuminate said array with said modulated polarised light to generate plasmons in said assay spots by total internal reflection of said polarised light;

a detection system to detect an orientation of an elliptical polarisation of said totally internally reflected modulated polarised light; and

an output to output a target sensing signal dependent on binding of a said biological target to a said functionalising molecule responsive to detection of a change in said elliptical polarisation orientation.

60. An apparatus as claimed in claim 59, wherein said polarisation modulator is pixellated for separate interrogation of said assay spots, and wherein said detection system is configured to enable separation of signals from different ones of said assay spots.

61. An apparatus as claimed in claim 59, configured to image dark-field scattered light through a black surface of said array.

63. A biosensor array for plasmon resonance-based sensing, the array having a surface bearing a plurality of assay spots, each of said assay spots comprising a conducting material for plasmon resonance sensing, and wherein the array further comprises at least one control spot, said control spot bearing a pattern of conductive elements such that light emitted by plasmon resonance in said control spot exhibits a pattern of interference or fringes.

64. A biosensor array as claimed in claim 63, wherein said control spot comprises an array of said conductive elements.

65. A biosensor array as claimed in claim 63, wherein said array of conductive elements comprises a regular array of conductive elements with a pitch of between 100 nm and 1800 nm.

66. A biosensor array as claimed in claim 63, wherein said conductive elements comprise a pattern in a conductive metallic layer on a substrate of said array.