Cycloalkyne-Functionalized Polymers for Post-Fabrication Biofunctionalization

Solution Overview

Problem

Current methods for functionalizing biodegradable polymers used in tissue engineering, such as poly(lactic acid), are complex and often lead to biocompatibility issues due to the need for harsh conditions and multi-step processes, which complicates the incorporation of bioactive molecules for guiding cellular behavior.

Innovation Solution

The use of strained cycloalkyne functionality in biocompatible polymers, which survives the fabrication process and allows for post-fabrication functionalization through strain-promoted azide alkyne cycloaddition click chemistry, enabling efficient and orthogonal biofunctionalization of polymeric structures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional chemical conjugation methods are used to functionalize biodegradable polymers, then bioactive molecules can be incorporated, but harsh conditions and multi-step processing are required which compromise biocompatibility

Engineering Contradiction:

Improvefunctionalization capabilityVSAvoidbiocompatibility

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The patent changes the chemical parameters of the functionalization reaction by using strain-promoted azide-alkyne cycloaddition instead of conventional copper-catalyzed click chemistry. This parameter change eliminates the need for copper catalysts and harsh conditions, allowing functionalization to proceed under biocompatible conditions while maintaining high efficiency and versatility.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent extracts and removes the harmful copper catalyst from the click chemistry reaction system. By using strain-promoted cycloaddition, the method achieves the same functionalization capability without requiring copper ions, thereby eliminating the toxic effects on biological systems while preserving the ability to incorporate bioactive molecules.

Inventive Principle:

Principle #2Taking out (Extraction)

2Ease of manufacture

If physical adsorption is used to incorporate biomolecules, then the process is simple, but biomolecules are lost over time

Engineering Contradiction:

Improvefunctionalization simplicityVSAvoidbiomolecule stability

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent incorporates reactive functional groups (strained cycloalkyne or azide groups) into the polymer structure during the fabrication process itself. This preliminary action ensures that the polymer is pre-equipped with reactive sites that will form stable covalent bonds with biomolecules in a subsequent single-step reaction, eliminating the need for complex multi-step processing while ensuring stable, long-term biomolecule retention.

Inventive Principle:

Principle #10Preliminary action

3Adaptability or versatility

If multi-step derivitization procedures are used, then surface functionalization can be achieved, but the process is time and resource intensive and may cause immune reactions

Engineering Contradiction:

Improvesurface functionalization capabilityVSAvoidprocessing complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent incorporates reactive functional groups (strained cycloalkyne or azide groups) into the polymer structure during the fabrication process itself. This preliminary action ensures that the polymer is pre-equipped with reactive sites that will form stable covalent bonds with biomolecules in a subsequent single-step reaction, eliminating the need for complex multi-step processing while ensuring stable, long-term biomolecule retention.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent extracts and removes the harmful copper catalyst from the click chemistry reaction system. By using strain-promoted cycloaddition, the method achieves the same functionalization capability without requiring copper ions, thereby eliminating the toxic effects on biological systems while preserving the ability to incorporate bioactive molecules.

Inventive Principle:

Principle #2Taking out (Extraction)

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

This approach allows for the precise and regiospecific functionalization of polymers with bioactive molecules, such as peptides and growth factors, without the need for harsh conditions, enhancing biocompatibility and facilitating the directed differentiation of stem cells into specific cell types.

Implementation Method 1

The cycloalkyne functionality can be beneficially employed in a post-fabrication functionalization through azidealkyne cycloaddition

Methodology Applied

Scientific EffectStrain-promoted azide alkyne cycloaddition: Chemical Bonding

Data Source

PatentUS9587070B2Polymeric structures containing strained cycloalkyne functionality for post-fabrication azidealkyne cycloaddition functionalization

Publication Date: 2017.03.07 THE UNIVERSITY OF AKRON

AI summary

A method of creating biocompatible polymeric structures includes the steps of: providing a biocompatible polymer including a strained cycloalkyne end group; forming a polymeric structure from the biocompatible polymer such that the strained cycloalkyne end group remains on the biocompatible polymer; providing an azide tethered molecule; and, after forming the polymeric structure, reacting the azide tethered molecule with the cycloalkyne in an azide alkyne cycloaddition reaction to further functionalize the polymeric structure.