Cation-π interaction mediated, anti-swelling, high-toughness and conductive hydrogel for regulation of PC12 neurite outgrowth

Abstract

The complex pathological processes and the interrupted impulse transmission pose significant challenges to repair neural damage. Mutifunctional hydrogels integrating biochemical and biophysical cues are sought after for neural tissue engineering scaffolds. However, the susceptibility to swelling and embrittlement of hydrogel severely compromise their stability. In this work, the electrically conductive, antioxidant and swelling resistant polyvinyl alcohol (PVA) hydrogel was fabricated by integrating cation-π interactions and polydopamine (PDA) 2D nanosheets, which drives the self-assembly of hydrogel to form new crystalline domains as demonstrated by Fourier transform infrared (FT-IR) spectra, X-ray diffraction and Raman spectroscopy. The mechanical properties were thoroughly investigated. Specifically, the tensile strength was 3 MPa and elongation at break was up to 580 % after saturated swelling (<0.80). The multifunctional PVA hydrogels showed the ability to scavenge the free radical and promote the axonal outgrowth especially with electrical stimulation (ES). An electroconductive, antioxidant, swelling resistant multifunctional hydrogel was demonstrated as a potential tissue scaffold for spinal cord injuries (SCI) reparation.