Electrically conductive scaffolds mimicking the hierarchical structure of cardiac myofibers

Abstract

Electrically conductive scaffolds, mimicking the unique directional alignment of muscle fibers in the myocardium, are fabricated using the 3D printing micro-stereolithography technique. Polyethylene glycol diacrylate (photo-sensitive polymer), Irgacure 819 (photo-initiator), curcumin (dye) and polyaniline (conductive polymer) are blended to make the conductive ink that is crosslinked using free radical photo-polymerization reaction. Curcumin acts as a liquid filter and prevents light from penetrating deep into the photo-sensitive solution and plays a central role in the 3D printing process. The obtained scaffolds demonstrate well defined morphology with an average pore size of 300 ± 15 μm and semi-conducting properties with a conductivity of ~ 10–6 S/m. Cyclic voltammetry analyses detect the electroactivity and highlight how the electron transfer also involve an ionic diffusion between the polymer and the electrolyte solution. Scaffolds reach their maximum swelling extent 30 min after immersing in the PBS at 37 °C and after 4 weeks they demonstrate a slow hydrolytic degradation rate typical of polyethylene glycol network. Conductive scaffolds display tunable conductivity and provide an optimal environment to the cultured mouse cardiac progenitor cells.

Self-Standing 3D-Printed PEGDA–PANIs Electroconductive Hydrogel Composites for pH Monitoring

“…However, the 3D printability evidenced for some of them has been exploited in additive manufacturing (AM) technologies, which are revolutionizing material preparation and processing methods [10][11][12]. In fact, AM has proven to be able to produce intricate, customizable, and functional structures and is easily integrated into electronic, biomedical, and sensor devices [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. Specifically, vat polymerization through stereolithography (SLA) can be considered one of the most convenient AM approaches.…”

Mimicked Spinal Cord Fibers Trigger Axonal Regeneration and Remyelination after Injury

“…Although synthetic polymers coated with ECM proteins can promote cell attachment, they fail to establish a stable microenvironment for nerve cells within the spinal cord due to insufficient ECM protein quantities. In previous studies, electrospinning technology has been used to produce aligned fibers with natural proteins or polysaccharides like fibrin, collagen, or chitosan. , However, this process often required the addition of organic solvents such as 1,1,1,3,3,3-hexafluoro-2-propanol (HFP) and 2,2,2-trifluoroethanol (TFE), or synthetic polymer poly­(ethylene oxide) (PEO) to reduce the surface tension of the spinning liquid and improve spinnability. , Unfortunately, it increases the risk of a solvent residue and protein denaturation. We developed a biocompatible electrospinning method to fabricate A-DSCF by using DSCM to mimic the structure and components of the natural spinal cord, eliminating the requirement for synthetic polymers or organic solvents.…”

“…In previous studies, electrospinning technology has been used to produce aligned fibers with natural proteins or polysaccharides like fibrin, collagen, or chitosan. 48,56 However, this process often required the addition of organic solvents such as 1,1,1,3,3,3-hexafluoro-2-propanol (HFP) and 2,2,2-trifluoroethanol (TFE), or synthetic polymer poly(ethylene oxide) (PEO) to reduce the surface tension of the spinning liquid and improve spinnability. 27,28 Unfortunately, it increases the risk of a solvent residue and protein denaturation.…”

Role of Precursors and Doping Agents in Producing 3D-Printed PEGDA–PDANI Electroactive Composites by an In Situ Polymerization Approach

“…AM allows designers and engineers to create 3D objects with complex and customized shapes, increasing design flexibility and leading to the development of innovative products with enhanced functionalities. − Among the different 3D printing technologies, light-induced ones [stereolithography (SLA) and digital light processing (DLP)] are well acknowledged for their superior precision and possibility to produce complex objects without the use of sacrificial materials …”