Cell Behavior Changes and Enzymatic Biodegradation of Hybrid Electrospun Poly(3-Hydroxybutyrate)-Based Scaffolds with an Enhanced Piezoresponse after the Addition of Reduced Graphene Oxide.

This is the first comprehensive study of the impact of biodegradation on the structure, surface potential, mechanical and piezoelectric properties of poly(3-hydroxybutyrate) (PHB) scaffolds supplemented with reduced graphene oxide (rGO) as well as cell behavior under static and dynamic mechanical conditions. There was no effect of the rGO addition up to 1.0 wt% on the rate of enzymatic biodegradation of PHB scaffolds for 30 days. The biodegradation of scaffolds led to the depolymerization of the amorphous phase, resulting in an increase in the degree of crystallinity. Because of more regular dipole order in the crystalline phase, surface potential of all fibers increased after the biodegradation, with a maximum (361 ± 5 mV) after the addition of 1 wt% rGO into PHB as compared to pristine PHB fibers. By contrast, PHB-0.7rGO fibers manifested the strongest effective vertical (0.59 ± 0.03 pm/V) and lateral (1.06 ± 0.02 pm/V) piezoresponse owing to greater presence of electroactive β-phase. In vitro assays involving primary human fibroblasts revealed equal biocompatibility and faster cell proliferation on PHB-0.7rGO scaffolds compared to pure PHB and nonpiezoelectric polycaprolactone scaffolds. Thus, the developed biodegradable PHB-rGO scaffolds with enhanced piezoresponse are promising for tissue-engineering applications. This article is protected by copyright. All rights reserved.