Engineering Electrospun Conductive Scaffolds to Investigate bone Cell Viability and Behaviour Under Electrical Stimulation for Bone Tissue Engineering

Abstract

Electroconductive scaffolds offer a promising approach to integrate structural guidance with bioelectric signals for bone tissue engineering. Methods: In this study, we developed electrospun polycaprolactone (PCL) scaffolds with varying amounts of carbon black (CB; 0, 15, 20, 25 wt%) and assessed their physicochemical properties and the responses of MG-63 osteoblast-like cells, both with and without direct current (DC) electrical stimulation. Analysis included SEM, contact-angle measurements, two-point electrical testing, while cell behaviour was evaluated by resazurin assays and DAPI/phalloidin imaging. A custom 24-well electrode plate was used to apply 1 V DC for either 30 or 60 minutes. Results: The addition of CB increased the fibre diameter and surface roughness while maintaining significant hydrophobicity (contact angles > 140°). Electrical testing showed a percolation transition between 15 and 20 wt% CB, marked by a significant decrease in resistance and an increase in conductivity, indicating the formation of a continuous conductive network. By Day 7, CB-containing scaffolds supported higher MG-63 metabolic activity than PCL (p < 0.05), consistent with improved adhesion on rougher conductive fibres. Conversely, 1 V DC for 30-60 minutes reduced metabolic activity versus non-stimulated controls by the final time point and disrupted actin organization, with more pronounced cytoskeletal rounding after 60 minutes, suggesting that non-uniform fields and electrochemical by-products in the custom setup likely contributed to these effects.