Bioactive hydrogel coatings of complex substrates using diffusion-mediated redox initiation.

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Medical Device Engineering

Background:

• Hydrogels offer tunable properties for cellular interactions and can functionalize medical devices as coatings.
• Uniformly coating complex 3D geometries with hydrogels is challenging without altering manufacturing or device function.

Purpose of the Study:

• To develop a novel, versatile method for applying conformable hydrogel coatings to diverse 3D substrates.
• To enable controlled thickness, chemistry, and bioactivity of hydrogel coatings via a simple post-fabrication process.

Main Methods:

• A diffusion-mediated redox-based crosslinking strategy was employed for hydrogel coating.
• Coating thickness was controlled by immersion time, initiating crosslinking via reducing agent desorption and diffusion.
• Macromer properties and sequential application were varied to tune coating characteristics and create multilayered constructs.

Main Results:

• The method successfully coated various 3D substrates without altering primary fabrication.
• Hydrogel properties, including thickness and chemistry, were tunable by adjusting process parameters and macromer characteristics.
• Sequential coating allowed for multilayered constructs with distinct features.
• Incorporation of proteins into hydrogel coatings introduced bioactivity, supporting cell attachment.

Conclusions:

• A versatile, diffusion-mediated redox-based crosslinking method enables conformable, tunable hydrogel coatings on complex 3D geometries.
• This post-fabrication process allows for controlled introduction of bioactivity, supporting cell attachment and offering potential for advanced medical devices.