QAC-Functionalized Thermoplastic Polyurethane Catheters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current anti-infective materials for catheters are ineffective in preventing biofilm formation and bacterial colonization due to limited activity duration and the development of antibiotic resistance, necessitating a sterile surface material with sustained contact-killing properties.
Innovation Solution
Development of functionalized thermoplastic polyurethanes (TPUs) with surface-grafted or bulk-incorporated quaternary ammonium compounds (QACs) that provide a sterile surface by killing microbes upon contact, preventing bacterial proliferation and biofilm formation on catheters and other medical devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional anti-infective materials are used on catheters, then initial antimicrobial protection is provided, but the activity duration is limited and antibiotic resistance develops
Solution Approach 1:
The catheter surface is pre-functionalized with quaternary ammonium compounds (QACs) through surface grafting or bulk incorporation during manufacturing. This preliminary incorporation ensures that antimicrobial agents are already present and active on the catheter surface from insertion, providing immediate and sustained contact-killing properties without requiring subsequent application or recharge
Solution Approach 2:
The patent modifies the chemical composition of the catheter material by incorporating QAC-functionalized polymers or grafting QACs onto the surface. This parameter change transforms the catheter from a passive surface to an actively antimicrobial surface with contact-killing properties that persist throughout the catheter's service life, extending activity duration while maintaining reliability
2Reliability
If antibiotics are used for prophylaxis to prevent catheter infections, then bacterial colonization is suppressed, but antibiotic-resistant pathogens emerge
Solution Approach 1:
The patent converts the potential harm of antibiotic overuse into benefit by replacing systemic antibiotic prophylaxis with localized contact-active QAC surfaces on catheters. This approach provides effective infection prevention while eliminating the selective pressure that drives antibiotic resistance, as QACs kill bacteria upon contact without allowing survival of resistant mutants
Solution Approach 2:
The patent substitutes chemical antibiotic prophylaxis with a physical-contact-based antimicrobial mechanism. QAC-functionalized catheter surfaces kill bacteria through direct contact, disrupting cell membranes and providing mechanical-like physical destruction rather than chemical inhibition, thereby preventing resistance development
3Reliability
If catheters have antimicrobial properties on both internal lumen and outer surface, then comprehensive protection against extraluminal and intraluminal infections is achieved, but engineering complexity increases
Solution Approach 1:
The patent creates a universal antimicrobial solution by functionalizing the entire catheter structure with QAC-containing materials or surface grafts. This multi-functional approach simultaneously provides structural integrity, biocompatibility, and broad-spectrum antimicrobial activity on all catheter surfaces (external, internal, and luminal), eliminating the need for separate antimicrobial treatments for different infection routes
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 QAC-functionalized TPUs effectively reduce microbial colonization and biofilm formation on medical devices, offering a durable and resistant antimicrobial surface that limits bacterial resistance and infection risk, thereby reducing the incidence of catheter-associated infections.
Implementation Method 1
quaternary ammonium compounds (QACs) that provide a sterile surface by killing microbes upon contact
Data Source
AI summary
In various embodiments, the present invention provides a functionalized thermoplastic polyurethane (TPU) containing bulk incorporated or surface-grafted quaternary ammonium compounds (QAC)s for contact-killing of a variety of microbes, where the QACs are on the surface of TPU to provide a sterile surface material that prevents bacteria commonly involved in device-associated infections (DAIs) from proliferating. The functionalized TPUs of the present invention can be formed into a wide variety of 3-dimensional shapes, such as catheters, medical tubing, laryngeal or tracheal stents, sutures, prosthetics, wound dressings, and/or a coating for medical devices and contains the residue of either a QAC containing diol monomer or an alkene functional diol monomer, which then allows the TPU to be functionalized with a QAC containing disulfide or free thiol compound, to form a quaternary ammonium functionalized thermoplastic polyurethane compound having antimicrobial properties for use in medical devices.