Well-Blended PCL/PEO Electrospun Nanofibers with Functional Properties Enhanced by Plasma Processing

Abstract

Biodegradable composite nanofibers were electrospun from poly(ε-caprolactone) (PCL) and poly(ethylene oxide) (PEO) mixtures dissolved in acetic and formic acids. The variation of PCL:PEO concentration in the polymer blend, from 5:95 to 75:25, revealed the tunability of the hydrolytic stability and mechanical properties of the nanofibrous mats. The degradation rate of PCL/PEO nanofibers can be increased compared to pure PCL, and the mechanical properties can be improved compared to pure PEO. Although PCL and PEO have been previously reported as immiscible, the electrospinning into nanofibers having restricted dimensions (250–450 nm) led to a microscopically mixed PCL/PEO blend. However, the hydrolytic stability and tensile tests revealed the segregation of PCL into few-nanometers-thin fibrils in the PEO matrix of each nanofiber. A synergy phenomenon of increased stiffness appeared for the high concentration of PCL in PCL/PEO nanofibrous mats. The pure PCL and PEO mats had a Young’s modulus of about 12 MPa, but the mats made of high concentration PCL in PCL/PEO solution exhibited 2.5-fold higher values. The increase in the PEO content led to faster degradation of mats in water and up to a 20-fold decrease in the nanofibers’ ductility. The surface of the PCL/PEO nanofibers was functionalized by an amine plasma polymer thin film that is known to increase the hydrophilicity and attach proteins efficiently to the surface. The combination of different PCL/PEO blends and amine plasma polymer coating enabled us to tune the surface functionality, the hydrolytic stability, and the mechanical properties of biodegradable nanofibrous mats.

Hydrophilic Surface Functionalization of Electrospun Nanofibrous Scaffolds in Tissue Engineering

“…Type of the plasma source, time, and pressure are the main parameters controlling the functionalization process [ 23 , 26 ]. The method allows one to modify PGA, PLLA, PLGA, PCL, PEO, PVDF, PU, or polyaniline (PANI) electrospun mats, by forming appropriate functional groups such as –COOH on the modified surface as an effect of plasma glow discharge with O 2 and C 3 H 4 O 2 in the gaseous form [ 26 , 67 , 68 , 69 ]. Plasma (ionized gas) generates free radicals on the surface, which can behave similarly to polar groups [ 23 ].…”

“…Plasma (ionized gas) generates free radicals on the surface, which can behave similarly to polar groups [ 23 ]. Therefore, the following types of sources can be distinguished: argon, oxygen, methane [ 64 , 65 , 66 , 67 , 68 , 69 , 70 ], ammonia/helium, nitrogen, or air [ 19 ]. The plasma source might significantly influence the surface wettability, introducing different functional groups, which affect the immobilization of bioactive molecules on the treated surface.…”

Core–Shell Eudragit S100 Nanofibers Prepared via Triaxial Electrospinning to Provide a Colon-Targeted Extended Drug Release

“…Thus, it is expected that three pumps must be the prerequisite for quantitatively driving the three different working fluids to the core, middle, and outer layer inlets of the spinneret at the same time. Certainly, other apparatuses can be added or combined with the electrospinning systems to expand their capability of creating novel nanomaterials [ 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 ].…”

Electrospun Functional Nanofiber Membrane for Antibiotic Removal in Water: Review

“…The preparation of electrospun functional membrane can be realized in three ways. Polymers with functions, such as adsorption, can be directly used to prepare electrospun functional nanofibers; the functional substances can be added into the working fluid to prepare the electrospun functional fiber membrane; the prepared electrospun fiber membrane can be endowed with membrane function by post-treatment techniques such as coating [ 107 , 108 ], heat treatment [ 109 , 110 ] and cross-linking [ 111 , 112 , 113 , 114 ]. (2) The prepared fiber membrane needs to be hydrophilic but insoluble in water.…”