Conductive Polymeric-Based Electroactive Scaffolds for Tissue Engineering Applications: Current Progress and Challenges from Biomaterials and Manufacturing Perspectives

Abstract

The practice of combining external stimulation therapy alongside stimuli-responsive bio-scaffolds has shown massive potential for tissue engineering applications. One promising example is the combination of electrical stimulation (ES) and electroactive scaffolds because ES could enhance cell adhesion and proliferation as well as modulating cellular specialization. Even though electroactive scaffolds have the potential to revolutionize the field of tissue engineering due to their ability to distribute ES directly to the target tissues, the development of effective electroactive scaffolds with specific properties remains a major issue in their practical uses. Conductive polymers (CPs) offer ease of modification that allows for tailoring the scaffold’s various properties, making them an attractive option for conductive component in electroactive scaffolds. This review provides an up-to-date narrative of the progress of CPs-based electroactive scaffolds and the challenge of their use in various tissue engineering applications from biomaterials perspectives. The general issues with CP-based scaffolds relevant to its application as electroactive scaffolds were discussed, followed by a more specific discussion in their applications for specific tissues, including bone, nerve, skin, skeletal muscle and cardiac muscle scaffolds. Furthermore, this review also highlighted the importance of the manufacturing process relative to the scaffold’s performance, with particular emphasis on additive manufacturing, and various strategies to overcome the CPs’ limitations in the development of electroactive scaffolds.

Conductive Scaffolds for Bone Tissue Engineering: Current State and Future Outlook

“…Through the incorporation of CPs such as PANI and PPy, researchers have been able to produce scaffolds with increased conductivity, these values have been similar to cortical and cancellous bone tissue in some cases [ 154 , 155 ]. Additionally, the performance of conductive polymer-based scaffolds, in terms of bone formation, can further be enhanced through exogenous ES (i.e., direct current and capacitive coupling), specific examples presented in the following section [ 156 ].…”

“…The incorporation of conductive materials into the development of scaffolding for bone is of significant interest due to the electrical properties this tissue [ 153 , 156 ]. The use of conductive materials can not only improve several aspects of tissue regeneration but specifically improve cell-scaffold interactions such as adhesion and proliferation [ 138 , 173 ].…”

Current methods for fabricating 3D cardiac engineered constructs

“…In addition, the modification of polymers used allows for the alteration of fiber characteristics such as fiber morphology, diameter, and biocompatibility ( Fang et al., 2010 ). The focus of newly developed polymers has shifted toward increasing biocompatibility of the scaffold, preserving CM contractility ( Gouveia et al., 2017 ), and increasing polymer conductance ( Marsudi et al., 2021 ) to optimize cardiac output and viability of cardiac engineered tissue models.…”

Formation of PLGA–PEDOT: PSS Conductive Scaffolds by Supercritical Foaming

“…These structures provide the mechanical properties that are especially required, particularly for tissue repair. Poly(lactic-co-glycolic acid) (PLGA), polyvinylpyrrolidone (PVP), polylactide (PLA), polycaprolactone (PCL), polyvinyl acetate (PVAc), or polyvinyl alcohol (PVA) are some of the compounds often used for this purpose [ 21 ]. PLGA, in particular, is often preferred for this type of biomedical objective for a number of reasons, namely, due to its mechanical properties, its composition-dependent biodegradability, and its easy production by different methods [ 22 , 23 , 24 ].…”