Affinity Particle Copolymer for Low Nonspecific Adsorption

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing affinity particles used in latex agglutination immunoassays suffer from high nonspecific adsorption and complex chemical processes, leading to reduced sensitivity and stability, making them unsuitable for industrial applications.

Innovation Solution

A particle composition comprising a copolymer with repeating units having sulfide groups or secondary amines and hydroxy groups, along with reactive functional groups like carboxyl groups, is synthesized through a simplified two-step process to enhance hydrophilicity and suppress nonspecific adsorption, ensuring high sensitivity and stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If epoxy groups of SG particles are converted to carboxyl groups through multiple-stage chemical reactions, then reactive functional groups for ligand binding are introduced, but nonspecific adsorption suppression capability is degraded

Engineering Contradiction:

Improvereactive functional group availabilityVSAvoidnonsspecific adsorption

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The invention changes the chemical parameter of the particle surface by introducing a copolymer containing sulfide groups or secondary amines alongside hydroxy groups. This parameter change provides both reactive functional groups for ligand binding and maintains hydrophilicity for nonspecific adsorption suppression, resolving the contradiction between adaptability and harmful factor reduction.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention uses a composite copolymer structure combining multiple functional groups (sulfide/secondary amine groups for reactivity and hydroxy groups for hydrophilicity) within a single particle system. This composite approach allows simultaneous achievement of ligand binding capability and nonspecific adsorption suppression.

Inventive Principle:

Principle #40Composite materials

2Adaptability or versatility

If multiple-stage chemical reactions are used to introduce carboxyl groups, then reactive functional groups are obtained, but the chemical reaction process becomes complicated

Engineering Contradiction:

Improvereactive functional group availabilityVSAvoidchemical reaction process

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The invention performs preliminary action by pre-introducing the copolymer containing both reactive groups (sulfide/secondary amine) and hydrophilic groups (hydroxy) during particle synthesis. This preliminary incorporation eliminates the need for subsequent multiple-stage chemical reactions to introduce functional groups, simplifying the overall process while maintaining adaptability.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The invention merges the introduction of reactive functional groups and hydrophilic groups into a single copolymer synthesis step. By combining these functions in one material rather than adding them separately through multiple reactions, the process complexity is reduced while maintaining both adaptability and nonspecific adsorption suppression.

Inventive Principle:

Principle #5Merging (Combining)

3Stability of the object's composition

If excessive dispersion stability is achieved, then particle stability is improved, but particles are unlikely to agglutinate and sensitivity is reduced

Engineering Contradiction:

Improvedispersion stabilityVSAvoiddetection sensitivity

Core Design Contradiction:

Stability of the object's compositionVSMeasurement precision

Solution Approach 1:

The invention carefully balances the parameter of dispersion stability by controlling the content of hydrophilic groups (hydroxy groups) in the copolymer. The hydroxy group content is specifically controlled to be 1-50 μmol/mg to achieve optimal balance between dispersion stability and agglutination capability, ensuring both stability and sensitivity.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention applies local quality by creating regions with different functional group distributions on the particle surface. The copolymer structure provides localized hydrophilic regions (hydroxy groups) for dispersion stability while maintaining reactive regions (sulfide/secondary amine groups) for ligand binding, enabling both stability and sensitivity.

Inventive Principle:

Principle #3Local quality

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The new particles exhibit superior nonspecific adsorption suppression, enabling high sensitivity and stability in latex agglutination immunoassays, facilitating accurate detection of target substances with improved reaction efficiency and dispersion stability.

Implementation Method 1

hydrophilicity of this glycol reduces the nonspecific adsorption

Methodology Applied

Scientific EffectHydrophilicity: Hydrophile

Implementation Method 2

causing an epoxy group derived from glycidyl (meth)acrylate of the particulate copolymer to chemically react with a thiol group

Methodology Applied

Scientific EffectChemical reaction: Chemical Bonding

Data Source

PatentUS12539504B2Particle, method for producing particle, affinity particle, and reagent and kit including the same

Publication Date: 2026.02.03 CANON KK

AI summary

A particle includes a copolymer including a repeating unit A having, in a side chain, a sulfide group or a secondary amine, and three or more hydroxy groups, and a repeating unit B having, in a side chain, at least one reactive functional group for binding a ligand, in which nonspecific adsorption is suppressed.