Gel-Shell Capsule Assemblies for Stable Droplet Integration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing droplet assemblies are unstable and limited in size and properties, making them unsuitable for a wide range of applications due to the instability of amphipathic layers, which disintegrate when removed from the bulk medium and are difficult to tailor for specific uses.

Innovation Solution

A method for preparing self-supporting assemblies of capsules by integrating shells formed from a reaction between a body medium and a bulk medium, allowing for control over size and properties, using a reaction-diffusion process that forms a gel capsule shell, enabling robust and durable assemblies that can withstand manipulation and storage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If amphipathic molecules are used to stabilise droplets at interfaces, then droplet assembly can be formed, but the assembly becomes unstable and disintegrates when removed from bulk medium

Engineering Contradiction:
Improvedroplet assembly stabilityVSAvoidapplication range
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent changes the fundamental parameter of droplet stabilization from amphipathic molecular layers to calcium alginate gel shells formed through chemical reaction. This transformation enables the droplets to maintain structural integrity when removed from bulk medium, significantly improving reliability and expanding application versatility to include spray drying and freeze drying processes.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention utilizes phase transition by forming a gel shell through the reaction of calcium ions with alginate. This gel phase transition creates a stable capsule structure that maintains droplet integrity during removal from bulk medium and enables subsequent drying processes without disintegration.

Inventive Principle:
Principle #36Phase transitions

2Volume of moving object

If droplets are made larger for practical applications, then utility increases, but amphipathic bilayers become unstable

Engineering Contradiction:
Improvedroplet sizeVSAvoidamphipathic layer stability
Core Design Contradiction:
Volume of moving objectVSReliability

Solution Approach 1:

The patent fundamentally changes the stabilization mechanism from size-dependent amphipathic layers to chemistry-based calcium alginate gel shells. This allows droplets to be scaled up to practical sizes (millimeter scale) while maintaining stability, as the gel shell strength is determined by chemical crosslinking density rather than surface area to volume ratio.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If amphipathic layers are used to form droplet assemblies, then droplet stabilization is achieved, but the assemblies are difficult to tailor for specific applications

Engineering Contradiction:
Improvedroplet stabilizationVSAvoidassembly property tailoring
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The invention transforms the system from using fixed amphipathic molecules to using tunable calcium alginate gel shells. The shell properties can be tailored by adjusting alginate concentration, calcium ion concentration, crosslinking time, and shell thickness, enabling customization for different applications including controlled release rates and mechanical strength requirements.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite capsule structure with a gel shell formed from calcium alginate. This composite material combines the stabilizing properties of gel networks with the encapsulation capability, allowing independent optimization of shell strength, porosity, and degradation characteristics for specific applications.

Inventive Principle:
Principle #40Composite materials

4Ease of manufacture

If droplet assemblies are created in bulk medium, then self-assembly occurs, but the assemblies cannot be isolated for further manipulation

Engineering Contradiction:
Improveself-assembly processVSAvoidassembly isolation and manipulation
Core Design Contradiction:
Ease of manufactureVSEase of operation

Solution Approach 1:

The calcium alginate gel shell formation creates a distinct phase boundary that allows easy separation of droplets from bulk medium. The gel shell acts as a protective barrier during isolation, and the stable structure enables subsequent manipulation including spray drying and freeze drying without disintegration.

Inventive Principle:
Principle #36Phase transitions

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 method produces assemblies that are fully self-supporting, allowing for control over size and properties, and are stable in various media, overcoming the limitations of previous droplet assemblies by providing increased biocompatibility and adaptability for diverse applications.

Implementation Method 1

integrating shells formed from a reaction between a body medium and a bulk medium, allowing for control over size and properties, using a reaction-diffusion process that forms a gel capsule shell

Methodology Applied
Scientific EffectReaction-diffusion process: Diffusion

Implementation Method 2

using a reaction-diffusion process that forms a gel capsule shell, enabling robust and durable assemblies that can withstand manipulation and storage

Methodology Applied
Scientific EffectGel formation: Gel

Data Source

PatentEP3268123B1Droplet assemblies and methods for producing droplet assemblies
Publication Date: 2022.01.05 DOVETAILED LIMITED
  • EP3268123B1 patent drawingFigure 1(a)~1(c)
  • EP3268123B1 patent drawingFigure 2(a)~2(c)
  • EP3268123B1 patent drawingFigure 3(a)~3(h)

AI summary

Provided is a method for preparing an assembly of integrated capsules, the method comprising the steps of: (i) providing a first body comprising a body reagent, wherein the body reagent is, or is contained within, a body medium; (ii) contacting the first body with a bulk medium comprising a bulk reagent, and permitting a first capsule shell to form at the boundary between the body medium and the bulk medium, thereby providing a first capsule, wherein the shell comprises a product of a reaction involving the body reagent and the bulk reagent; (iii) providing a second body comprising a body reagent, wherein the body reagent is, or is contained within, a body medium; (iv) contacting the second body with a bulk medium comprising a bulk reagent, and permitting a second capsule shell to form at the boundary between the second body medium and the bulk medium, thereby providing a second capsule, wherein the shell comprises a product of a reaction involving the body reagent and the bulk reagent; and (v) permitting the first and second capsule shells to integrate, thereby forming an assembly of first and second bodies. An assembly obtained or obtainable by the method is also provided.