3D Printing of Polycaprolactone–Polyaniline Electroactive Scaffolds for Bone Tissue Engineering

Abstract

Electrostimulation and electroactive scaffolds can positively influence and guide cellular behaviour and thus has been garnering interest as a key tissue engineering strategy. The development of conducting polymers such as polyaniline enables the fabrication of conductive polymeric composite scaffolds. In this study, we report on the initial development of a polycaprolactone scaffold incorporating different weight loadings of a polyaniline microparticle filler. The scaffolds are fabricated using screw-assisted extrusion-based 3D printing and are characterised for their morphological, mechanical, conductivity, and preliminary biological properties. The conductivity of the polycaprolactone scaffolds increases with the inclusion of polyaniline. The in vitro cytocompatibility of the scaffolds was assessed using human adipose-derived stem cells to determine cell viability and proliferation up to 21 days. A cytotoxicity threshold was reached at 1% wt. polyaniline loading. Scaffolds with 0.1% wt. polyaniline showed suitable compressive strength (6.45 ± 0.16 MPa) and conductivity (2.46 ± 0.65 × 10−4 S/cm) for bone tissue engineering applications and demonstrated the highest cell viability at day 1 (88%) with cytocompatibility for up to 21 days in cell culture.

Investigating the Effect of Carbon Nanomaterials Reinforcing Poly(ε-Caprolactone) Printed Scaffolds for Bone Repair Applications

“…Despite the promising results obtained with these scaffolds, they are not electrically conductive, which is a limiting characteristic of bone regeneration. To address this issue, our group also developed strategies to induce electroconductive properties on PCL-based scaffolds by mixing PCL with conductive polymers[ 18 ] or with low concentration of other conductive materials such as graphene (G) and carbon nanotubes (CNTs)[ 17 , 19 , 20 ].…”

In vivo study of conductive 3D printed PCL/MWCNTs scaffolds with electrical stimulation for bone tissue engineering

“…These polymers are usually synthesized as a composite with non-conductive biocompatible and degradable polymers such as PCL [15], poly(D, L-lactide) (PDLLA) [16] and poly (L-lactic) acid (PLLA) [17]. However, challenges still remain for these polymers due to their manufacturing limitation (some of them cannot be melted), potential toxicity and poor solubility in solvents [18][19][20]. Inorganic conductive materials including graphene, carbon nanofibers and carbon nanotubes are also being investigated [21].…”

3D Printable Electrically Conductive Hydrogel Scaffolds for Biomedical Applications: A Review

“…Conversely, PCL/PANI hybrid scaffolds were 3D printed (using FDM method) from PCL melt containing PANI powder dispersed. The 3D printed hybrid scaffolds exhibited compressive modulus of 6.45 ± 0.16 MPa, electrical conductivity of 2.46 ± 0.65 × 10 −4 S cm −1 , and outstanding human adipose-derived stem cell viability, which has potential for bone tissue engineering applications and implantable biodevices [ 40 ].…”