Cross-linked Polyoxazoline Tissue Adhesive
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional tissue adhesives, such as cyanoacrylate and fibrin-based sealants, face limitations in internal applications due to toxic degradation products, high costs, slow curing, limited mechanical strength, and viral infection risks, while PEG-based hydrogel adhesives suffer from rapid swelling or dissolution, insufficient cohesion, and uncontrollable properties.
Innovation Solution
A biocompatible, covalently cross-linked polyoxazoline (POX) polymer is developed by reacting electrophilically activated POX with a nucleophilic cross-linking agent, providing tissue-adhesive properties through unreacted electrophilic groups that can react with tissue components, allowing for control over adhesiveness, mechanical strength, swelling, and biodegradability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If PEG-based hydrogel tissue adhesives are used, then non-toxic properties are improved, but swelling and dissolution occur too quickly
Solution Approach 1:
The patent changes the chemical composition parameters by using polyoxazoline backbones with controlled molecular weights and degrees of polymerization, and adjusts the crosslinking density to achieve slow degradation rates while maintaining non-toxic properties. The electrophilic groups are incorporated at controlled densities to provide sustained adhesion.
Solution Approach 2:
The invention creates a composite material system combining polyoxazoline backbone with electrophilic functional groups (such as NHS esters, anhydrides, or isocyanates) and crosslinking agents. This composite structure provides both the biocompatibility of PEG-based materials and the enhanced durability through controlled crosslinking networks.
2Strength
If conventional tissue adhesives like cyanoacrylate are used, then adhesive strength is improved, but toxic degradation products are released
Solution Approach 1:
The patent employs biodegradable polyoxazoline materials that break down into non-toxic products, replacing permanent or long-lasting conventional adhesives. The controlled degradation allows the adhesive to perform its function and then safely disappear, eliminating toxic accumulation.
Solution Approach 2:
The invention converts the potential harm of degradation into a benefit by designing the polyoxazoline structure to degrade into non-toxic, biocompatible products. The degradation process itself becomes beneficial for tissue healing while maintaining adhesive strength during the required period.
3Object-affected harmful factors
If fibrin-based adhesives are used, then biocompatibility is improved, but mechanical strength and curing speed are limited
Solution Approach 1:
The patent adjusts the molecular weight, polydispersity, and functional group density of the polyoxazoline to optimize the balance between mechanical strength and biocompatibility. The crosslinking density is carefully controlled to provide sufficient mechanical properties while maintaining degradation and adhesion characteristics.
4Strength
If electrophilically activated POX is cross-linked with nucleophilic cross-linking agent, then tissue adhesion and mechanical properties are improved, but polymerization control becomes more difficult
Solution Approach 1:
The patent incorporates electrophilic groups (such as NHS esters, anhydrides, or isocyanates) into the polyoxazoline structure during synthesis, before the crosslinking step. This preliminary functionalization allows for controlled and predictable crosslinking reactions when the nucleophilic crosslinking agent is introduced, simplifying the overall process control.
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 cross-linked POX polymer offers enhanced tissue adhesion, controlled mechanical properties, and sustained drug release, with improved stealth and antifouling behavior, suitable for various medical applications including wound closure and drug delivery.
Implementation Method 1
reacting electrophilically activated polyoxazoline (EL-POX) with a cross-linking agent... the m electrophilic groups are capable of reaction with the n nucleophilic groups to form covalent bonds
Implementation Method 2
unreacted electrophilic groups that are capable of reacting with tissue components... electrophilic groups that can react with nucleophile-containing components naturally present in tissue
Implementation Method 3
sustained drug release... The release of drugs, such as antibiotics, growth factors like VEGF and osteogenic factor (BMP-2), may be sustained by slow diffusion from the interconnecting network
Data Source
AI summary
A biocompatible, covalently cross-linked, polymer that is obtained by reacting an electrophilically activated polyoxazoline (EL-POX) with a nucleophilic cross-linking agent is disclosed. The EL-POX comprises m electrophilic groups; and the nucleophilic cross-linking agent comprises n nucleophilic groups, wherein the m electrophilic groups are capable of reacting with the n nucleophilic groups to form covalent bonds; wherein m≥2, n≥2 and m+n≥5; wherein at least one of the m electrophilic groups is a pendant electrophilic group and/or wherein m≥3; and wherein the EL-POX comprises an excess amount of electrophilic groups relative to the amount of nucleophilic groups contained in the nucleophilic cross-linking agent. Biocompatible medical products and kits comprising the cross-linked POX-polymers are also disclosed.