Amine-Functionalized Electrically Conductive Core–Sheath MEH-PPV:PCL Electrospun Nanofibers for Enhanced Cell–Biomaterial Interactions

Abstract

In the present study, a conducting polymer, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) along with a biodegradable polymer poly(ε-caprolactone) (PCL) was used to prepare an electrically conductive, biocompatible, bioactive and biodegradable nanofibrous scaffold for possible use in neural tissue engineering applications. Core-sheath electrospun nanofibres of PCL as the core and MEH-PPV as the sheath, were surface-functionalized with (3-aminopropyl) triethoxysilane (APTES) and 1,6-hexanediamine to obtain amine functionalized surface to facilitate cell-biomaterial interactions with the aim of replacing the costly biomolecules such as collagen, fibronectin, laminin and arginyl-glycylaspartic acid (RGD) peptide for surface modification. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed the formation of core-sheath morphology of the electrospun nanofibres, while Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) revealed successful incorporation of amine functionality after surface functionalization. Adhesion, spreading and proliferation of 3T3 fibroblast were enhanced on the surface functionalized electrospun meshes, while the neuronal model rat pheochromocytoma 12 (PC12) cells also adhered and differentiated into sympathetic neurons on these meshes. Under a constant electric field of 200 mV for 2h/day for 3 consecutive days, the PC12 cells displayed remarkable improvement in the neurite formation and outgrowth on the surface functionalized meshes that was comparable to those on the collagen coated meshes under no electrical signal. Electrical stimulation studies further demonstrated that electrically stimulated PC12 cells cultured on collagen I coated meshes yielded more and longer neurites than those of the unstimulated cells on the same scaffolds. The enhanced neurite growth and differentiation suggest the potential use of these scaffolds for neural tissue engineering applications.

In vitro and in vivo advancement of multifunctional electrospun nanofiber scaffolds in wound healing applications: Innovative nanofiber designs, stem cell approaches, and future perspectives

“…These nanofibers also provide an excellent microniche for cellular activities, including cell adhesion, migration, long‐term survival, and proliferation 15 . Moreover, the nanosized pores, hierarchical porous structures with excellent interconnectivity, the flexibility of ENs in surface functional group grafting, 13,16 and improved mechanical functions (stiffness, elasticity, and tensile strength, etc.) are significant advantages of this technique.…”

Current methodologies and approaches for the formation of core–sheath polymer fibers for biomedical applications

“…144 The surface functionalization of electrically conductive PCL core and MEH-PPV sheath nanofibers enhances the cell-biomaterial interaction, and the electric field stimulated cell culture showed a remarkable improvement in the neurite formation and growth in neural tissue engineering. 145 Figure 26 shows 3T3 cell interaction with materials, attachment, and spreading after 3 days of culture. Figure 27 demonstrates the immunolabeling of beta (III) tubulin in differentiated PC12 cells with DAPI-stained nuclei after a 7 day culture on surface functionalized PCL-MEH-PPV core-sheath fibers.…”

Generation of Core–Sheath Polymer Nanofibers by Pressurised Gyration

“…Modifying the nanofibers by incorporation of additional layer or layers can enhance the performances of functional scaffolds and architectures that are used in regenerative medicine to repair damaged tissues and develop artificial organs [ 13 , 14 ]. In addition, nanoparticles, drugs, proteins, peptides, growth factors, and other bioactive components could be embedded, coated, and encapsulated within the core–sheath structure and their use regulated more accurately in a time-programmed manner [ 15 , 16 , 17 , 18 ].…”