Extracellular Vesicle Isolation via Aqueous Two-Phase System

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional methods for isolating extracellular vesicles, such as ultracentrifugation and size exclusion, face challenges like low yield, long isolation times, and high costs, while immunoaffinity and polymeric methods suffer from low purity and long processing times, making them unsuitable for practical and economical diagnosis.

Innovation Solution

A method using an aqueous two-phase system comprising immiscible materials like polyethylene glycol and dextran, which allows for rapid isolation of extracellular vesicles by concentrating them at a phase boundary, followed by centrifugation, to achieve high yield and purity within a short time.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If ultracentrifugation isolation is used, then reliability of isolation is improved, but productivity is worsened due to low yield and long isolation time

Engineering Contradiction:

Improveisolation reliabilityVSAvoidisolation productivity

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent changes the physical-chemical parameters of the isolation system by introducing an aqueous two-phase system with specific polymer concentrations (e.g., PEG 8000 at 4% and dextran 500 at 2% w/v). This creates distinct density phases that enable vesicle separation based on their physical properties, achieving both high reliability and high productivity without requiring ultracentrifugation

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent replaces the mechanical ultracentrifugation system with a chemical-physical aqueous two-phase system. Instead of using high-speed rotation and centrifugal force, the invention uses polymer-induced phase separation and density gradient formation to achieve vesicle isolation, dramatically reducing isolation time while maintaining reliability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Manufacturing precision

If size exclusion method is used, then purity of extracellular vesicles is improved, but productivity is worsened due to low yield from vesicle adhesion to filter

Engineering Contradiction:

Improvevesicle purityVSAvoidisolation yield

Core Design Contradiction:

Manufacturing precisionVSProductivity

Solution Approach 1:

The patent introduces polymer solutions (PEG and dextran) as intermediary substances that create a phase boundary. Vesicles are trapped at this boundary rather than adhering to a filter surface, eliminating the adhesion problem while maintaining separation effectiveness and high yield

Inventive Principle:

Principle #24Intermediary (Mediator)

3Productivity

If polymeric method is used, then productivity is improved by rapid precipitation, but purity is worsened due to protein co-precipitation

Engineering Contradiction:

Improveisolation speedVSAvoidprecipitate purity

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The patent creates local quality differentiation by forming distinct aqueous phases with different densities and chemical properties. Vesicles concentrate at the phase boundary where local polymer concentration creates selective trapping, while proteins remain in the bulk phase, achieving both rapid isolation and high purity

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

This method significantly increases isolation efficiency, achieving yields four times higher than ultracentrifugation within 10-20 minutes, while maintaining high purity, making it suitable for practical and economical disease diagnosis.

Implementation Method 1

preparing an aqueous two-phase system by mixing a first material and a second material, which are immiscible with each other, with a body fluid or an aqueous solution containing extracellular vesicles

Methodology Applied

Scientific EffectPhase separation: Two-Phase Flow

Implementation Method 2

isolating the extracellular vesicles concentrated at a phase boundary between the first material and the second material of the aqueous two-phase system

Methodology Applied

Scientific EffectDensity gradient separation: Density Gradient

Implementation Method 3

centrifuging the aqueous two-phase system at 100 ∼5,000×g-force

Methodology Applied

Scientific EffectCentrifugal force: Centrifugal Force

Data Source

PatentUS11016009B2Method for isolating extracellular vesicles using aqueous two-phase system

Publication Date: 2021.05.25 POSTECH ACADEMY INDUSTRY FOUNDATION

AI summary

Disclosed is a method of isolating extracellular vesicles using an aqueous two-phase system (ATPS), including (a) preparing an ATPS by mixing a first material and a second material, which are immiscible with each other, with a body fluid or an aqueous solution containing extracellular vesicles and (b) isolating extracellular vesicles concentrated in the second material of the ATPS. This method can exhibit very high isolation efficiency, a simple isolation manner, and a very short isolation time. The isolation of extracellular vesicles using the ATPS requires no ultracentrifuge and achieves almost 100% isolation efficiency within a short time of about 10˜20 min, and thus the method of the invention is practical, is economical due to low costs thereof, can increase the purity of extracellular vesicles contaminated with protein, enables the diagnosis of disease using the isolated extracellular vesicles, and can be applied to various fields using extracellular vesicles.