A robust, biocompatible scaffold for peripheral nerve regeneration: integration of PLLA nanofibers with a RGD-like poly(amidoamine) hydrogel

Abstract

This work reports on a nanocomposite scaffold (PLLA-AGMA1) designed to support Schwann cell growth and promote peripheral nerve regeneration. The system combines a poly(L-lactic acid) (PLLA) electrospun network, providing mechanical stability and suturability, with a polyamidoamine hydrogel (AGMA1) designed to mimic the extracellular matrix. AGMA1 was synthesized via polyaddition of agmatine with 2,2-bis-acrylamidoacetic acid, using a 25 % excess of acrylamide functions to enable UV-induced crosslinking without additional initiators. The reactive end groups formed covalent bonds with nitrogen plasma-activated PLLA nanofibers. Physicochemical analyses confirmed the formation of a uniform, hydrophilic network with high swelling capacity (75–80 %) and preserved structural integrity. The material exhibited stable thermo-mechanical behavior and could withstand suturing. It might be noticed that the maximum tensile strength of PLLA-AGMA1 was comparable to that peripheral nerves (0.6 vs 0.8 MPa, respectively). Degradation studies showed progressive degradation of AGMA1 over time, favoring cell infiltration. Human Schwann cells cultured on PLLA-AGMA1 displayed excellent viability, adhesion, and proliferation up to 9 days of incubation, supporting the scaffold’s suitability for nerve repair. The fabrication process, comprising electrospinning, plasma treatment, and UV crosslinking without intermediate purification, was straightforward and scalable, highlighting the clinical potential of this robust, biocompatible scaffold for peripheral nerve regeneration.