Injectable, mixed natural-synthetic polymer hydrogels with modular properties

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Drug Delivery

Background:

• Developing injectable hydrogels with tunable properties is crucial for in vivo applications.
• Existing methods often require complex chemistries or lack precise control over material characteristics.

Purpose of the Study:

• To engineer injectable, rapidly gelling hydrogels with tunable properties.
• To establish a modular mixing approach for creating covalently cross-linked hydrogel networks.

Main Methods:

• Functionalization of synthetic oligomers (poly(N-isopropylacrylamide)) and carbohydrate polymers (hyaluronic acid, carboxymethyl cellulose, dextran, methylcellulose) with hydrazide or aldehyde groups.
• In situ gelling via double-barreled syringe mixing to form hydrazone-cross-linked hydrogels.
• Modular mixing of reactive precursors to create hydrogel networks with varied polymeric components.

Main Results:

• Successfully created in situ gelling, hydrazone-cross-linked hydrogels through simple mixing.
• Demonstrated the ability to produce hydrogels with defined swelling, degradation, phase transition, drug binding, and mechanical properties.
• Showcased selective modification of hydrogel properties by adjusting precursor ratios.

Conclusions:

• The modular mixing approach offers a highly adaptable method for engineering injectable hydrogels.
• This technique allows for precise control over hydrogel properties, intermediate to the selected precursors.
• The developed hydrogels show significant potential for in vivo applications, including drug delivery.