Decoupling Bioactivity and Processability: RGD Click-Functionalized Coatings for a 3D-Printed PCL Scaffold

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Polymer Chemistry

Background:

• Developing functionalized scaffolds with improved bioactivity is crucial for bone tissue engineering (BTE).
• Poly(ε-caprolactone) (PCL) scaffolds offer a promising base but often require surface modification to enhance cellular interactions.
• Current methods may integrate bioactivity during printing, limiting customization.

Purpose of the Study:

• To present a modular strategy for surface functionalization of 3D-printed PCL scaffolds.
• To enhance the bioactivity of PCL scaffolds by covalently conjugating an RGD peptide.
• To create a versatile platform for regenerative medicine applications.

Main Methods:

• A three-step synthesis created a maleimide-functionalized PCL derivative (PCL-AE-L).
• Dip-coating applied the functionalized polymer onto 3D-printed PCL scaffolds, preserving architecture.
• Covalent conjugation of a thiol-modified RGD peptide yielded PCL@RGD scaffolds.

Main Results:

• Functionalization steps were confirmed using NMR, FTIR, DSC, GPC, and SEM-EDX.
• Coating stability was validated under simulated culture conditions.
• In vitro assays demonstrated significantly improved SAOS-2 cell adhesion and mineralization on PCL@RGD scaffolds compared to controls.

Conclusions:

• The modular strategy successfully imparts enhanced cell-adhesive properties to PCL scaffolds.
• This approach decouples bioactivity enhancement from the printing process, allowing customizable surface functionalization.
• The developed PCL@RGD scaffolds represent a versatile platform for next-generation BTE and regenerative medicine.