Microcell Transdermal Patch for Hydrophilic Drug Delivery

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current transdermal delivery systems for hydrophilic active molecules, such as pharmaceuticals, face limitations in variability of concentrations and release profiles, often requiring multiple patches or frequent applications to achieve desired doses, and are prone to crystallization issues that reduce shelf life.

Innovation Solution

A transdermal delivery system utilizing microcells filled with aqueous formulations of hydrophilic active molecules, sealed with a hydrophobic layer and overlaid with a porous diffusion layer, allowing for varying types, concentrations, and volumes of actives to be delivered from a single system, with microcells arranged in arrays for controlled release.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If matrices and gels are used to stabilize hydrophilic active molecules for transdermal delivery, then the active molecules can be delivered transdermally, but the amount of hydrophilic active that can be captured and released is limited and requires large quantities of non-active materials

Engineering Contradiction:
Improveamount of hydrophilic active deliveredVSAvoidquantity of non-active materials required
Core Design Contradiction:
Quantity of substanceVSDevice complexity

Solution Approach 1:

The invention divides the delivery system into discrete microcapsules, each containing hydrophilic active molecules in an aqueous core. This segmentation allows multiple microcapsules to be delivered via a single patch, increasing the total amount of active that can be delivered without proportionally increasing the amount of matrix material. Each microcapsule is a self-contained unit that can be independently formulated and controlled.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention changes the physical state and formulation parameters by using aqueous cores within microcapsules rather than traditional gel or matrix systems. This allows for higher concentrations of hydrophilic actives to be encapsulated and delivered, as the aqueous environment better stabilizes hydrophilic molecules compared to hydrophobic matrices.

Inventive Principle:
Principle #35Parameter changes

2Quantity of substance

If multiple matrix-containing patches or frequent gel applications are used to achieve high doses, then sufficient active delivery can be achieved, but patient compliance decreases and the system becomes more complex

Engineering Contradiction:
Improvedose of hydrophilic activeVSAvoidpatient compliance
Core Design Contradiction:
Quantity of substanceVSEase of operation

Solution Approach 1:

The invention merges multiple doses of hydrophilic active into a single transdermal patch by incorporating numerous microcapsules within the patch matrix. This allows a high total dose to be delivered through one application rather than requiring multiple patches or repeated applications, significantly improving patient compliance and ease of use.

Inventive Principle:
Principle #5Merging (Combining)

3Stability of the object's composition

If hydrophilic active molecules are stabilized in traditional matrices, then transdermal delivery is enabled, but the active molecules may crystalize during storage limiting shelf life

Engineering Contradiction:
Improvestability of hydrophilic activeVSAvoidshelf life of delivery system
Core Design Contradiction:
Stability of the object's compositionVSDuration of action of stationary object

Solution Approach 1:

The invention introduces an aqueous core as an intermediary environment within microcapsules to stabilize hydrophilic active molecules. This aqueous medium better matches the solubility requirements of hydrophilic actives, preventing crystalization during storage. The microcapsule structure acts as a protective intermediary barrier that maintains molecular stability throughout the shelf life of the product.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Manufacturing precision

If a single transdermal system delivers varying concentrations of hydrophilic actives, then precise control of release profile is achieved, but the system complexity increases

Engineering Contradiction:
Improvecontrol of release profileVSAvoidsystem structure
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The invention applies local quality by formulating microcapsules with different wall compositions, thicknesses, or porosity characteristics to achieve different release profiles. Each microcapsule can be locally optimized for its specific active molecule and desired release kinetics, while the overall patch maintains a unified structure. This allows precise control of release profiles without requiring a completely complex system architecture.

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

Enables precise control over the delivery of hydrophilic active molecules, including pharmaceuticals, with the ability to vary types and concentrations, improving patient compliance and extending shelf life by allowing for on-demand release and long-term delivery of actives.

Implementation Method 1

the opening is spanned by a porous diffusion layer

Methodology Applied
Scientific EffectDiffusion: Diffusion

Implementation Method 2

The microcells include an opening, and the opening is spanned by a hydrophobic sealing layer

Methodology Applied
Scientific EffectHydrophobicity: Hydrophobe

Data Source

PatentEP3709980B1Microcell systems for delivering hydrophilic active molecules
Publication Date: 2024.01.10 E INK CORP
  • EP3709980B1 patent drawingFigure 1~3
  • EP3709980B1 patent drawingFigure 4
  • EP3709980B1 patent drawingFigure 5A~5B

AI summary

A hydrophilic active molecule delivery system whereby active molecules can be released on demand and/or a variety of different active molecules can be delivered from the same system and/or different concentrations of active molecules can be delivered from the same system. The system may be used to deliver/release hydrophilic active ingredients, generally.