Oxidase activity of polymeric coated cerium oxide nano-particles

• US 10,261,074 B1
• Filed: 11/10/2014
• Issued: 04/16/2019
• Est. Priority Date: 03/17/2009
• Status: Active Grant

• Current Assignee: University of Central Florida Research Foundation Inc. (State University System of Florida)
• Original Assignee: University of Central Florida Research Foundation Inc. (State University System of Florida)
• Inventors: Perez, Jesus Manuel, Asati, Atul, Santra, Santimukul, Kaittanis, Charalambos, Nath, Sudip
• Primary Examiner(s): Yakovleva, Galina
• Application Number:
  US14/537,102
• Time in Patent Office: 1,618 Days
• CPC Class Codes: B01J 2231/005 General concepts, e.g. reviews, relating to methods of using catalyst systems, the concept being defined by a common method or theory, e.g. microwave heating or multiple stereoselectivity
• CPC Class Codes: B01J 31/26 containing in addition, inorganic metal compounds not provided for in groups B01J31/02 - B01J31/24
• 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: G01N 33/5432 Liposomes or microcapsules
• CPC Class Codes: G01N 33/54346 Nanoparticles
• CPC Class Codes: G01N 33/57423 of lung
• CPC Class Codes: G01N 33/582 with fluorescent label
• CPC Class Codes: G01N 33/587 Nanoparticles
• CPC Class Codes: G01N 33/9413 Dopamine

Abstract

Methods, systems, compositions include biocompatible polymer coated nanoceria that function as aqueous redox catalyst with enhanced activity at an acidic to moderately alkaline pH value between 1 and 8. The compositions are used as oxidizing agents for decomposition, decontamination or inactivation of organic contaminants, such as, pesticides and chemical warfare agents. Another use includes nanoceria as targetable nanocatalyst prepared by conjugating various targeting ligands to the nanoparticle coating to form a colorimetric or fluorescent probe in immunoassays and other molecule binding assays that involve the use of a molecule in solution that changes the color of the solution or emits a fluorescent signal, where localization of nanoceria to organs or tissue is assessed by treatment with an oxidation sensitive dye or other detection devices. Versatility and uses of the nanoceria compositions are controlled by pH value, choice of dye substrate and thickness of the polymer coating on the ceria nanoparticles.

Claims

1. A polymer coated nanoceria particle that is useful as a colorimetric probe in immunoassays that involve the use of a molecule in solution that upon oxidation by the polymer coated nanoparticle changes color, the polymer coated nanoceria particle comprising a cerium oxide core with an average hydrodynamic diameter of approximately 7 nm, and a polymer coating with a thickness to an extent such that said polymer coated cerium oxide nanoparticles have an average hydrodynamic diameter in a range from approximately 12 nm to approximately 100 nm, wherein the polymer coated nanoceria particle comprises pH dependent oxidase activity;

wherein the polymer coated nanoceria particle comprises targeting ligands conjugated to the coating on the nanoceria particle; and

wherein the polymer coated nanoceria particle oxidizes the molecule in the absence of a peroxide, oxidase or peroxidase.

2. The polymer coated nanoceria particle of claim 1, wherein the immunoassay is Enzyme-Linked ImmunoSorbent Assay (ELISA).

3. The polymer coated nanoceria particle of claim 1, wherein the peroxidase is horseradish peroxidase and the peroxide is hydrogen peroxide.

4. The polymer coated nanoceria particle of claim 1, further comprising Protein G or Protein A conjugated thereto.

5. The polymer coated nanoceria particle of claim 4, further comprising an antibody conjugated thereto.

6. The polymer coated nanoceria particle of claim 1, wherein said particle oxidizes chromogenic dye substrates at a pH of 1.0 to 4.0 and chromogenic/fluorescent dye substrates at a pH of 4.0 to 8.0.