Catalytic signal enhancement for lateral flow immunoassays

Patent metadata

Field	Value
Publication number	US-11209429-B2
Application number	US-201916401411-A
Country	US
Kind code	B2
Filing date	May 2, 2019
Priority date	May 3, 2018
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

The present invention provides a method for increasing the sensitivity of LFIAs by using palladium nanoparticles, selecting appropriate dye chemistries, and improving the timing of the development chemistry. In the presence of a palladium nanoparticle, three reagents interact with a catalytic label to form a colored dye. The three reagents include a hydrogen peroxide source, a color developer (a substituted para-phenylenediamine), and a color coupler (e.g. a napthol or a phenol). The timing of the development chemistry is improved by any combination of using a reducing agent, delaying hydrogen peroxide application by diffusion, using dissolving materials as a time delay, using serpentine flow, and separating the color coupler and the color developer on the strip.

First claim

What is claimed is:

1. A method for improving a catalytic signal for a lateral flow immunoassay, comprising:
providing a lateral flow immunoassay comprising
a source of hydrogen peroxide, wherein the source of hydrogen peroxide comprises sodium percarbonate;
a substituted para-phenylenediamine;
a phenol or napthol;
palladium nanoparticles; and
a time delay mechanism; and

interacting the substituted para-phenylenediamine, the phenol or napthol, and the hydrogen peroxide with the palladium nanoparticles to form a dye that is a visual label for the lateral flow immunoassay, wherein the time delay mechanism delays the interaction of at least one of the substituted para-phenylenediamine, the phenol or napthol, or the hydrogen peroxide with the palladium nanoparticles thereby improving the catalytic signal.

2. A method for improving a catalytic signal for a lateral flow immunoassay, comprising:
providing a lateral flow immunoassay comprising
a source of hydrogen peroxide;
a substituted para-phenylenediamine, wherein the substituted para-phenylenediamine comprises N-ethyl-N-(2-hydroxyethyl)-2-methyl-1,4-phenylenediamine (HEPDA) or N,(2-((4-amino-3-methylphenyl)(ethyl)amino)ethylmethanesulfonamide (MSPDA);
a phenol or napthol;
palladium nanoparticles; and
a time delay mechanism; and

interacting the substituted para-phenylenediamine, the phenol or napthol, and the hydrogen peroxide with the palladium nanoparticles to form a dye that is a visual label for the lateral flow immunoassay, wherein the time delay mechanism delays the interaction of at least one of the substituted para-phenylenediamine, the phenol or napthol, or the hydrogen peroxide with the palladium nanoparticles thereby improving the catalytic signal.

3. A method for improving a catalytic signal for a lateral flow immunoassay, comprising:
providing a lateral flow immunoassay comprising
a source of hydrogen peroxide;
a substituted para-phenylenediamine;
a phenol or napthol;
palladium nanoparticles; and
a time delay mechanism, wherein the time delay mechanism comprises using a dissolving material to slow a fluid flow in the lateral flow immunoassay; and

interacting the substituted para-phenylenediamine, the phenol or napthol, and the hydrogen peroxide with the palladium nanoparticles to form a dye that is a visual label for the lateral flow immunoassay, wherein the time delay mechanism delays the interaction of at least one of the substituted para-phenylenediamine, the phenol or napthol, or the hydrogen peroxide with the palladium nanoparticles thereby improving the catalytic signal.

4. A method for improving a catalytic signal for a lateral flow immunoassay, comprising:
providing a lateral flow immunoassay comprising
a source of hydrogen peroxide;
a substituted para-phenylenediamine;
a phenol or napthol;
palladium nanoparticles; and
a time delay mechanism, wherein the time delay mechanism comprises using a serpentine flow in the lateral flow immunoassay; and

interacting the substituted para-phenylenediamine, the phenol or napthol, and the hydrogen peroxide with the palladium nanoparticles to form a dye that is a visual label for the lateral flow immunoassay, wherein the time delay mechanism delays the interaction of at least one of the substituted para-phenylenediamine, the phenol or napthol, or the hydrogen peroxide with the palladium nanoparticles thereby improving the catalytic signal.

5. A method for improving a catalytic signal for a lateral flow immunoassay, comprising:
providing a lateral flow immunoassay comprising
a source of hydrogen peroxide;
a substituted para-phenylenediamine;
a phenol or napthol;
palladium nanoparticles; and
a time delay mechanism, wherein the time delay mechanism comprises combining a reducing agent with the substituted para-phenylenediamine, the phenol or napthol, or the hydrogen peroxide before interaction with the palladium nanoparticles; and

interacting the substituted para-phenylenediamine, the phenol or napthol, and the hydrogen peroxide with the palladium nanoparticles to form a dye that is a visual label for the lateral flow immunoassay, wherein the time delay mechanism delays the interaction of at least one of the substituted para-phenylenediamine, the phenol or napthol, or the hydrogen peroxide with the palladium nanoparticles thereby improving the catalytic signal.

Assignees

• Us Gov Sec Navy

Inventors

• Kidwell David A

Classifications

• G01N33/54346

  Nanoparticles · CPC title

• G01N33/533

  with fluorescent label · CPC title

• G01N2021/7756

  Sensor type · CPC title

• G01N33/531 Primary

  Production of immunochemical test materials · CPC title

• B82Y99/00

  Subject matter not provided for in other groups of this subclass · CPC title