Nanosilver Hydrogel Wound Dressing for Controlled Ion Release

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing wound dressings face challenges in achieving high antimicrobial activity while preventing silver particle absorption into the human body, which can lead to undesirable side effects such as skin discoloration, and they often fail to effectively promote wound healing and comfort during prolonged use.

Innovation Solution

A water-containing hydrogel composition with elemental silver particles of specific size distribution (5-20 nm) and concentration (15-500 ppm) is combined with a polyurethane-polyurea copolymer and nonionic surfactant, forming a multilayer wound dressing that allows controlled silver ion release for antimicrobial efficacy without cytotoxicity or allergic reactions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the amount of silver ions released is increased to enhance antimicrobial activity, then antimicrobial effectiveness is improved, but the risk of silver absorption into the human body increases leading to argyria

Engineering Contradiction:
Improveantimicrobial effectivenessVSAvoidsilver absorption and argyria risk
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent changes the particle size parameter of silver to nanoscale (5-20 nm average diameter, D90 ≤ 25 nm), which fundamentally alters the release behavior. This parameter change enables controlled ion release at therapeutic levels while preventing particle absorption, resolving the contradiction between antimicrobial effectiveness and safety

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite hydrogel system combining polyurethane-polyurea copolymer with nanosilver particles and nonionic surfactant. This composite structure provides controlled silver ion release while the hydrogel matrix prevents particle absorption, achieving both high antimicrobial activity and safety

Inventive Principle:
Principle #40Composite materials

2Reliability

If silver particles are used for antimicrobial activity, then antimicrobial effectiveness is improved, but particle release and absorption into the body occurs causing side effects

Engineering Contradiction:
Improveantimicrobial activityVSAvoidsilver particle absorption
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent extracts only the beneficial ionic form of silver while eliminating the harmful particulate form. The nanosilver particles serve as controlled sources of silver ions, which are released in controlled amounts, while the particles themselves remain trapped in the hydrogel matrix, preventing absorption

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The hydrogel matrix acts as an intermediary between the nanosilver particles and the body. It controls the release of silver ions while preventing particle migration, serving as a protective mediator that enables therapeutic effect without harmful absorption

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If a hydrogel composition with nanosilver is used for wound treatment, then antimicrobial activity is achieved, but the complexity of the composition increases

Engineering Contradiction:
Improveantimicrobial activityVSAvoidhydrogel composition complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The polyurethane-polyurea copolymer hydrogel matrix serves multiple functions simultaneously: it provides structural integrity, controls silver ion release, prevents particle absorption, and maintains wound moisture. This multi-functionality reduces the need for additional separate components, managing complexity while achieving antimicrobial activity

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

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 hydrogel composition achieves high antimicrobial effectiveness with controlled silver ion release, reducing germ levels by at least 3 logs, is non-cytotoxic, and promotes wound healing while maintaining comfort and moisture levels, suitable for long-term use.

Implementation Method 1

Due to the electrochemical potential of elemental silver, only small amounts of silver ions are released at a time, which can effectively inhibit or kill bacteria

Methodology Applied
Scientific EffectOxidation: Oxidation

Implementation Method 2

a water-containing hydrogel composition comprising elemental silver particles

Methodology Applied
Scientific EffectHydrogel: Hydrogel

Data Source

PatentEP3558401B1Water-containing hydrogel composition, comprising elemental silver particles
Publication Date: 2022.12.07 PAUL HARTMANN AG
  • EP3558401B1 patent drawingFigure 1
  • EP3558401B1 patent drawingFigure 2
  • EP3558401B1 patent drawingFigure 3A~3B

AI summary

The invention relates to a water-containing hydrogel composition, comprising elemental silver particles, and a multi-layer wound dressing comprising the hydrogel composition. The multi-layer wound dressing is used in particular in the inflammation and/or granulation phase to treat, for example, burns and/or chronic wounds. The invention further relates to a method for producing the hydrogel composition.