Microfluidic Channel Traps for Magnetic Particle Concentration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing immunoassay systems face challenges in efficiently detecting and quantifying substances of interest in fluids, particularly in small volumes, due to limitations in fluid routing and particle concentration methods.
Innovation Solution
A microfluidic channel design with strategically placed traps and an external magnetic field source is used to route fluidic flow towards a sensing area, allowing for the accumulation and quantification of magnetic particles, which provides a clear indication of substance presence or concentration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional immunoassay systems are used to detect substances in small fluid volumes, then detection capability is maintained, but fluid routing efficiency and particle concentration are insufficient
Solution Approach 1:
The microfluidic channel is segmented into distinct functional zones: a sample application area, a sensing area with traps, and an exit point. This segmentation allows optimized fluid routing and particle concentration in the sensing area, enabling efficient detection in small fluid volumes while maintaining high detection efficiency
Solution Approach 2:
The sensing area is designed with local quality enhancements through the incorporation of traps with specific geometries (V-shaped or U-shaped) and the application of a magnetic field. This creates a localized region of enhanced particle concentration capability, allowing efficient detection of substances in small fluid volumes without requiring the entire system to be optimized for high-speed processing
2Quantity of substance
If magnetic beads are used as solid phase for capture probe, then high surface area for capture probe attachment is achieved, but complex alignment systems and secondary antibody capture sites are required
Solution Approach 1:
The invention merges the magnetic bead concentration function with the detection function by incorporating traps directly into the microfluidic channel at the sensing area. The magnetic field source and traps work together to concentrate magnetic beads in a localized region, eliminating the need for separate secondary antibody capture sites and complex alignment systems while maintaining high capture probe surface area
Solution Approach 2:
The microfluidic channel design with integrated traps and magnetic field source enables the system to self-concentrate magnetic beads at the sensing area through the combined action of fluid flow routing and magnetic field application. This self-service mechanism eliminates the need for external complex alignment systems and secondary capture sites, simplifying the overall device architecture while maintaining high detection efficiency
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
This approach enables rapid and accurate analysis of small fluid volumes, providing a reliable and consistent method for detecting substances of interest with reduced complexity and no need for secondary antibody capture sites or complex alignment systems.
Implementation Method 1
The sensing area is provided with an orientated external magnetic field by means of a suitable magnetic field source
Implementation Method 2
The particular design of the microfluidic channel may be adapted to facilitate the routing of the fluid containing the particles and substance of interest from a sample application area towards the sensing area
Data Source
Figure 1~3
AI summary
An assay apparatus having an assay strip (6). The assay strip (6) has a first area (2) with a plurality of magnetic particles bonded thereto. The assay strip (6) also has a microfluidic (or nanofluidic) channel or chamber, having a sensing area comprising one or more magnetic particle traps (7, 8, 9) and a magnetic field source (5) provided adjacent to the sensing area. Introduction of a fluid causes the magnetic particles to become attached to or displaced by a substance of interest, travel along the microfluidic channel to the sensing area and become concentrated in the one or more traps (7, 8, 9) thus providing an indication of the presence or absence of a substance of interest in the fluid. There may be a plurality of traps (7, 8, 9).