Triple-Layered Electrospun Microfibers for Cell Viability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing electrospun microtubes and microfibers face challenges in maintaining high cell viability and density, as they are not effectively protected from harmful solvents and do not allow for sufficient nutrient and gas diffusion.

Innovation Solution

A concentric triple-layered microfiber structure is developed, comprising an exterior layer of organic-soluble polymers, an intermediate layer of water-soluble polymers, and an internal layer with high cell concentration, where the intermediate layer acts as a barrier to protect cells and facilitate diffusion of nutrients and gases.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If cells are incorporated at high concentration in electrospun microfibers, then cell density is improved, but cell viability deteriorates due to solvent harm and insufficient nutrient diffusion

Engineering Contradiction:
Improvecell concentrationVSAvoidcell viability
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The microfiber is divided into multiple concentric layers (exterior layer, intermediate layer, internal layer) with distinct functions. The exterior layer provides structural integrity and solvent barrier, the intermediate layer enables nutrient diffusion and gas exchange, and the internal layer protects and sustains high cell concentration. This segmentation allows simultaneous achievement of high cell density and cell viability by addressing different requirements in different spatial zones.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different layers are assigned different material properties and functions tailored to local requirements: the exterior layer uses organic-soluble polymers for structural stability and solvent resistance, the intermediate layer uses water-soluble polymers for nutrient permeability, and the internal layer provides a cell-friendly environment. This local differentiation of material properties enables the system to simultaneously satisfy conflicting requirements of high cell concentration and high cell viability.

Inventive Principle:
Principle #3Local quality

2Reliability

If an intermediate barrier layer is added to protect cells from solvent harm, then cell viability is improved, but device complexity increases

Engineering Contradiction:
Improvecell viabilityVSAvoidmicrofiber structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The protective intermediate layer is nested within the concentric multi-layered structure of the microfiber, with the interior layer containing cells nested within the intermediate layer, which is itself nested within the exterior layer. This nested configuration allows the protective function to be integrated into the overall fiber structure without requiring separate external protective components, thereby minimizing added complexity while maximizing protective benefit.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The microfiber employs composite material construction with three distinct polymeric layers, each composed of different materials with specific properties: organic-soluble polymers in the exterior layer, water-soluble polymers in the intermediate layer, and cell-compatible materials in the internal layer. This composite structure integrates multiple functions (protection, diffusion, structural integrity) into a single unified component, avoiding the need for separate protective devices and thus limiting complexity increase.

Inventive Principle:
Principle #40Composite materials

3Reliability

If a triple-layered concentric structure is implemented, then cell viability and density are improved, but manufacturing precision requirements increase

Engineering Contradiction:
Improvecell viabilityVSAvoidconcentric layer alignment precision
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The electrospinning process merges the formation of all three concentric layers into a single simultaneous manufacturing step, rather than requiring sequential assembly of separate layers. The co-axial capillary design allows three different polymeric solutions to be extruded concurrently to form the exterior, intermediate, and internal layers in one continuous process, significantly reducing the precision requirements compared to multi-step assembly methods and eliminating alignment issues between separately manufactured components.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The intermediate layer acts as a mediator between the exterior and internal layers, with its water-soluble polymer composition enabling controlled diffusion of nutrients and gases while maintaining structural integrity. This intermediary layer with specific permeability properties facilitates the transport of essential substances to the cell-containing internal layer, supporting high cell viability and density without requiring complex external delivery systems.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 design enables the incorporation of extremely high concentrations of viable cells within the microfiber, with the intermediate layer ensuring cell viability and density by preventing solvent harm and allowing necessary nutrient and gas exchange.

Implementation Method 1

electrospun microfibers and/or microtubes

Methodology Applied
Scientific EffectElectrostatic forces: Electrostatics

Implementation Method 2

facilitate diffusion of nutrients and gases

Methodology Applied
Scientific EffectDiffusion: Diffusion

Implementation Method 3

said intermediate layer and/or interior layer are substantially porous layers

Methodology Applied
Scientific EffectPorosity: Porosity

Data Source

PatentEP3271502B1Multi-layered microfibers and use thereof
Publication Date: 2024.10.02 NANOSPUN TECHNOLOGIES LTD
  • EP3271502B1 patent drawingFigure 1
  • EP3271502B1 patent drawingFigure 2A~2C

AI summary

Multi-layered electrospun microfibers and/or microtubes, comprising cells and/or molecules of interest. The invention is further directed to compositions comprising said microfibers and/or microtubes and methods of use thereof in various applications.