Shape-Memory Catheter Topographies for Biofilm Prevention

Solution Overview

Problem

Current medical devices, such as catheters, face significant challenges in preventing bacterial biofilm formation due to the high resistance of biofilms to antimicrobial agents and their role in chronic infections and antimicrobial resistance, with existing topographic surfaces being largely empirical and ineffective in long-term applications.

Innovation Solution

The development of surface topographies on medical devices made from shape memory polymers that can transform in response to stimuli, such as heat, to prevent bacterial adhesion and remove established biofilms, utilizing specific patterns like narrow line patterns and hexagonal shapes to reduce biofilm formation and dislodge attached bacteria.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional topographic surfaces are used to prevent bacterial adhesion, then some antifouling effect is achieved, but the effect is largely empirical and ineffective in long-term applications

Engineering Contradiction:

Improvelong-term antifouling effectivenessVSAvoidempirical design approach

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent employs shape memory polymers that can dynamically change their surface topography in response to thermal stimuli. The surface transitions from a flat state during insertion to a patterned state (with protrusions or recesses) at body temperature, providing adaptive antifouling protection that activates only when needed, thereby improving long-term effectiveness without complicating the manufacturing process

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention utilizes temperature as a control parameter to trigger the transformation of the shape memory polymer surface. By changing the temperature from room temperature to body temperature, the surface topology changes from flat to patterned, providing a controlled and reproducible method to achieve reliable antifouling effects without relying on empirical design approaches

Inventive Principle:

Principle #35Parameter changes

2Reliability

If shape memory polymer surfaces with topographic patterns are used, then biofilm formation is reduced by up to 99.9%, but the device requires thermal stimulation to activate the antifouling mechanism

Engineering Contradiction:

Improvebiofilm prevention effectivenessVSAvoidactivation requirement

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The shape memory polymer catheter surface activates its antifouling pattern automatically upon insertion into the patient's body. The body temperature itself serves as the trigger, eliminating the need for external thermal stimulation or complex activation mechanisms. The surface self-regulates its topology based on the environmental temperature, providing ease of operation while maintaining high biofilm prevention effectiveness

Inventive Principle:

Principle #25Self-service

3Reliability

If static topographic patterns are used to prevent bacterial adhesion, then some antifouling protection is provided, but established biofilms cannot be removed

Engineering Contradiction:

Improvebiofilm removal capabilityVSAvoiddynamic shape transformation

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent employs shape memory polymers that can dynamically change their surface topography in response to thermal stimuli. The surface transitions from a flat state during insertion to a patterned state (with protrusions or recesses) at body temperature, providing adaptive antifouling protection that activates only when needed, thereby improving long-term effectiveness without complicating the manufacturing process

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention utilizes temperature as a control parameter to trigger the transformation of the shape memory polymer surface. By changing the temperature from room temperature to body temperature, the surface topology changes from flat to patterned, providing a controlled and reproducible method to achieve reliable antifouling effects without relying on empirical design approaches

Inventive Principle:

Principle #35Parameter changes

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 described surface topographies significantly reduce biofilm formation by up to 99.9% and effectively remove established biofilms, providing prolonged antifouling properties without using antimicrobials, and are effective against various bacterial species, including Pseudomonas aeruginosa and Staphylococcus aureus.

Implementation Method 1

a surface that can transform from a first topography to a second topography that is different than said first topography. The surface is formed from a shape memory polymer and transforms from said first topography to said second topography in response to a trigger, such as heat

Methodology Applied

Scientific EffectShape memory polymer transformation: Shape Memory Polymer

Data Source

PatentUS11406792B2Antifouling urinary catheters with shape-memory topographic patterns

Publication Date: 2022.08.09 SYRACUSE UNIVERSITY

AI summary

A system of topographic patterns for the prevention of bacterial adhesion and biofilm formation. The patterns may be provided on the surfaces of certain devices that are prone to bacterial adhesion and biofilm formation, such as urinary catheters. To reduce bacterial adhesion and biofilm formation, and to remove existing biofilms, the patterns are induced to transform from a first topography to a second topography. For example, the surface patterns may be formed from a shape memory polymer and then heated to transform the patterns from the first topography to the second topography to dislodge bacteria and prevent fouling.