Dual-Excitation Flow Analysis for Single-Particle Velocity Correlation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Flow-based analysis of small particles, such as extracellular vesicles, is challenging due to their high diffusivity and varying velocities within channels, making it difficult to differentiate and characterize them effectively.

Innovation Solution

A method involving a microfluidic chip with a high-NA air objective and dual excitation light sources, coupled with emission fiber bundles and photodetectors, allows for precise interrogation and characterization of particles and molecules by correlating emission signals to determine velocity and colocalize target molecules.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If flow-based analysis is used for small particles, then particle analysis capability is improved, but measurement precision deteriorates due to high diffusivity and velocity variation

Engineering Contradiction:
Improveparticle analysis capabilityVSAvoidparticle differentiation precision
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent segments the flow analysis into discrete interrogation zones along the channel, with multiple detection points that sample particles at different positions. This segmentation allows reconstruction of particle properties by combining measurements from multiple zones, overcoming the limitation of single-point measurement precision

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transitions from single-point measurement to multi-dimensional spatial sampling along the channel length. By measuring particles at multiple longitudinal positions and combining these measurements, the system achieves improved precision through dimensional expansion of the measurement space

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Measurement precision

If multiple detection points are used along the channel, then velocity measurement accuracy is improved, but device complexity increases

Engineering Contradiction:
Improvevelocity measurement accuracyVSAvoiddetection system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent implements a universal detection platform where identical detector modules are replicated at multiple positions along the channel. Each module performs the same measurement function, allowing standardized design and simplified manufacturing while achieving multi-point velocity measurements through temporal correlation of signals from different positions

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

Solution Approach 2:

The patent uses identical detector module copies at multiple channel positions rather than complex unique detectors at each location. This copying approach maintains measurement precision through replicated functionality while reducing device complexity through standardization and modular design

Inventive Principle:
Principle #26Copying

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

Enhances the detection and characterization of small particles and molecules by correcting for diffusion-based challenges, enabling accurate measurement and identification of sub-populations and concentrations.

Implementation Method 1

collecting emission light emitted from the channel with a light collection system comprising a high-NA air objective having a numerical aperture in a range of 0.91 to less than 0.99

Methodology Applied
Scientific EffectLight collection: Lens

Implementation Method 2

outputting first excitation light through an interrogation window onto a first portion of the channel; outputting second excitation light through the interrogation window onto a second portion of the channel distinct from the first portion; generating a first emission signal with a first photodetector based on first emission light received

Methodology Applied
Scientific EffectFluorescence emission: Fluorescence

Data Source

PatentEP4244600B1Method and apparatus for flow-based, single-particle and/or single-molecule analysis
Publication Date: 2026.03.18 UNIV OF WASHINGTON
  • EP4244600B1 patent drawingFigure 1A
  • EP4244600B1 patent drawingFigure 1B~2
  • EP4244600B1 patent drawingFigure 3A~3B

AI summary

Systems and methods for analyzing particles flowing in a channel are described. In an embodiment, the channel is configured to flow a particle through a lumen of the channel, the channel defining an interrogation window configured to allow light to pass into and out of the lumen; a light engine comprising: a first light source positioned to output first excitation light onto a first portion of the channel in the interrogation window; and a second light source positioned to output second excitation light onto a second portion of the channel in the interrogation window separate from the first portion. In an embodiment, the systems include an emission fiber bundle comprising a first emission optical fiber and a second emission optical fiber, wherein a proximal end of first emission optical fiber and second emission optical fiber are arranged in an emission fiber bundle head.