Lateral Flow Device for Blood Group Antigen Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for determining blood group antigens using incomplete antibodies, such as IgG, are limited by their inability to directly agglutinate erythrocytes, requiring phase or technology changes and additional incubation steps, especially when standardized IgM antibodies are not available for certain antigens, complicating simultaneous determination of multiple analytes.

Innovation Solution

A device and method utilizing a separation matrix with indicator zones containing incomplete antibodies and binding elements, allowing for the simultaneous determination of blood group antigens using a single lateral flow or gel matrix, where incomplete antibodies are paired with secondary antibodies to facilitate agglutination, reducing the need for multiple steps and environments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If incomplete antibodies (IgG) are used to detect blood group antigens, then the detection can be performed for antigens where IgM antibodies are not available, but the antibodies cannot directly agglutinate erythrocytes, requiring additional incubation steps and phase changes

Engineering Contradiction:
Improvedetection capability for antigens without IgM antibodiesVSAvoidprocess complexity with multiple incubation steps
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent introduces a secondary antibody as an intermediary that bridges the incomplete antibody (IgG) and the erythrocyte. The secondary antibody binds to the incomplete antibody-antigen complex and provides the necessary Fc region interactions to enable agglutination, thus mediating the detection process without requiring phase changes or additional incubation steps

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent combines the incomplete antibody and the secondary antibody into a single reagent mixture that can be applied in one step. This merging of components allows the entire detection process to occur in a single homogeneous phase without requiring separate incubation steps or phase changes

Inventive Principle:
Principle #5Merging (Combining)

2Measurement precision

If multiple blood group antigens are determined using conventional methods, then comprehensive blood typing is achieved, but different phases and reaction times are required for different antigens, complicating simultaneous determination

Engineering Contradiction:
Improvecomprehensive blood group characterizationVSAvoidanalysis time for simultaneous determination
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent creates a universal detection system where the combination of incomplete antibodies and secondary antibodies can detect multiple different blood group antigens (both IgM and IgG reactive) using the same reagent mixture and procedural steps, eliminating the need for separate testing protocols for different antigen types

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges multiple detection capabilities into a single homogeneous reaction mixture that can simultaneously detect multiple blood group antigens. By combining incomplete antibodies specific to different antigens with a universal secondary antibody, the system achieves simultaneous determination of multiple blood group characteristics in one step

Inventive Principle:
Principle #5Merging (Combining)

3Speed

If standardized IgM antibodies are used for blood group antigen detection, then direct hemagglutination occurs enabling rapid detection, but this approach is not available for certain antigens requiring incomplete antibodies

Engineering Contradiction:
Improvedetection speed with direct hemagglutinationVSAvoidavailability for all antigen types
Core Design Contradiction:
SpeedVSAdaptability or versatility

Solution Approach 1:

The secondary antibody serves as a mediator that restores the direct hemagglutination capability to incomplete antibodies. By binding to the incomplete antibody-antigen complex, the secondary antibody enables rapid visual detection similar to direct hemagglutination, thus maintaining detection speed while expanding versatility to include antigens that only react with incomplete antibodies

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the effective valency and binding characteristics of the antibody system by introducing the secondary antibody. This parameter change transforms the incomplete antibody from a non-agglutinating reagent into one that produces visible agglutination, enabling rapid detection without sacrificing adaptability to different antigen types

Inventive Principle:
Principle #35Parameter changes

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

Enables rapid and simultaneous determination of blood group antigens without the need for phase changes or additional incubation, significantly reducing the time required for analysis and simplifying the process by using a single homogeneous step in a lateral flow or gel card.

Implementation Method 1

the indicator zone comprises a first antibody directed against the blood group antigen or a fragment thereof and a binding element directed against the first antibody

Methodology Applied
Scientific EffectAntibody-antigen binding:

Implementation Method 2

Antibodies that cannot directly agglutinate erythrocytes are analogously referred to as incomplete antibodies in blood group serology

Methodology Applied
Scientific EffectAgglutination:

Implementation Method 3

Test membranes in conventional lateral flow tests typically use chromatography-like separation

Methodology Applied
Scientific EffectChromatography: Chromatography

Implementation Method 4

an absorbent absorption zone that allows the sample to be tested to flow through the separation membrane

Methodology Applied
Scientific EffectCapillary action: Capillary Action

Data Source

PatentEP3149477B1Device and method for detecting blood group antigens by means of an incomplete antibody
Publication Date: 2024.08.28 GRIFOLS DIAGNOSTIC SOLUTIONS INC
  • EP3149477B1 patent drawingFigure 1
  • EP3149477B1 patent drawingFigure 2
  • EP3149477B1 patent drawingFigure 3A~3e

AI summary

The invention relates to a device for determining a cellular-bound analyte in a liquid sample, comprising a separation matrix with at least one indicator zone. The invention is characterized in that the indicator zone comprises a first antibody directed against the cellular-bound analyte or a fragment thereof and a binding element directed against the first antibody, the first antibody being an incomplete antibody. The separation matrix is preferably designed in the form of the membrane of a lateral flow assay device or as a gel matrix. In a particularly preferable manner, the device comprises a membrane (2) with a charging zone (5) for applying the liquid sample, at least one indicator zone which can interact with the cellular-bound analyte, and at least one absorption region (3) which absorbs the liquid after passing the indicator zone. The indicator zone lies between the charging zone (5) and the absorption region (3). The invention is characterized in that the indicator zone comprises an antibody directed against the cellular-bound analyte or a fragment thereof and a binding element directed against the first antibody, the first antibody being an incomplete antibody.