Optical biosensing platform utilizing nanocrystalline zinc oxide

• US 8,114,679 B2
• Filed: 02/11/2008
• Issued: 02/14/2012
• Est. Priority Date: 09/11/2007
• Status: Expired due to Fees

• Current Assignee: USA As Represented By The Secretary of The Army
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Steeves, Diane M., Soares, Jason W.
• Primary Examiner(s): Gakh, Yelena G
• Assistant Examiner(s): Xu, Robert
• Application Number:
  US12/079,088
• Publication Number:
  US 20090068755A1
• Time in Patent Office: 1,464 Days
• Field of Search: None
• US Class Current: 436/172
• 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 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 5/00 Nanobiotechnology or nanomedicine, e.g. protein engineering or drug delivery
• CPC Class Codes: G01N 21/6489 Photoluminescence of semiconductors

Abstract

An optical biosensing platform for the real-time detection of the occurrence of a binding event, the optical biosensing platform comprising a nanocrystalline zinc oxide (nano-ZnO) substrate having a surface and being capable of emitting photoluminescence and a surface modifier formed integral with at least a portion of the surface of the nano-ZnO substrate, wherein the surface modifier is capable of binding to a biomolecule and wherein when the surface modifier binds with a biomolecule, a change is induced in the emitted photoluminescent properties of the nano-ZnO substrate, thereby enabling the detection of a binding event.

Claims

1. An optical biosensing platform for the real-time detection of the occurrence of a binding event, the optical biosensing platform comprising:

a nanocrystalline zinc oxide (nano-ZnO) substrate having a surface and being capable of emitting photoluminescence, said photoluminescence comprising an inherent photoluminescence signal consisting of two emission peaks, a first peak being within an ultraviolet (UV) region of an electromagnetic spectrum, and a second peak being within a visible region of the spectrum; and

a surface modifier being capable of binding to a biomolecule, said modifier formed integral with at least a portion of the surface of the nano-ZnO substrate, said surface modifier being chosen for attaching a specific receptor, said receptor for allowing the binding of a particular target biomolecule;

wherein when the surface modifier binds with a said biomolecule, a change is induced in the emission of the inherent photoluminescent properties of the nano-ZnO substrate, said change occurring in at least one of the group consisting of emission intensities, emission maxima shifts and peak proportionalities of the inherent photoluminescent properties of the nano-ZnO substrate thereby enabling the detection of a binding event.

2. An optical biosensing platform according to claim 1 wherein the surface modifier comprises a silane cross-linking agent, said agent for creating a Zn—

O—

Si bond at the surface of the ZnO substrate, and for introducing a chemical functionality for allowing coupling of biomolecules.

3. An optical biosensing platform according to claim 2 wherein the silane cross-linking agent is triethoxysilylundecanal.

4. An optical biosensing platform according to claim 1 wherein the biomolecule comprises at least one of the group consisting of antibodies, peptides, aptamers, pathogens, DNA, enzymes, proteins, cells, lipopolysaccharides, fluorescent dye hydrazide-derivatives and biotin.

5. A method for detecting the occurrence of a binding event, the method comprising:

providing an optical biosensing platform comprising;

a nanocrystalline zinc oxide (nano-ZnO) substrate having a surface and being capable of emitting photoluminescence, said photoluminescence comprising an inherent photoluminescence signal consisting of two emission peaks, a first peak being within an ultraviolet (UV) region of an electromagnetic spectrum, and a second peak being within a visible region of the spectrum; and

a surface modifier being capable of binding to a specific biomolecule, said modifier formed integral with at least a portion of the surface of the nano-ZnO substrate, said surface modifier being chosen for attaching a specific receptor, said receptor for allowing the binding of a particular target biomolecule,

wherein when the surface modifier binds with a said biomolecule, a change is induced in the emission of the inherent photoluminescent properties of the nano-ZnO substrate, said change occurring in at least one of the group consisting of emission intensities, emission maxima shifts and peak proportionalities of the inherent photoluminescent properties of the nano-ZnO substrate;

providing a sample which potentially contains at least one biomolecule capable of binding with the surface modifier; and

observing the nano-ZnO substrate to determine whether a said change in said inherent photoluminescent properties of the nano-ZnO substrate has been induced, thereby enabling the detection of a binding event.

6. A method for manufacturing an optical biosensing platform for the real-time detection of the occurrence of a binding event, the method comprising:

providing a nanocrystalline zinc oxide (nano-ZnO) substrate having a surface and being capable of emitting photoluminescence; and

integrating a surface modifier with at least a portion of the surface of the nano-ZnO substrate, wherein the surface modifier is capable of binding to a specific biomolecule, and wherein said surface modifier comprises a silane cross-linking agent, said integrating comprising;

attaching the agent to the nano-ZnO surface for introducing a chemical reactive group for allowing biofunctionalization;

verifying a presence of the agent;

confirming a concentration of Si on the surface;

washing the surface for removing any noncovalently attached agent; and

verifying stability of the chemical reactive group for maintaining functionality for forming a biomolecule complex.

7. A method according to claim 6 wherein the silane cross-linking agent is triethoxysilylundecanal.