Controlled drug release from electrospun PCL non-woven scaffolds via multi-layering and e-beam treatment

Currently, electrospun synthetic bioresorbable polymer scaffolds are applied in regenerative medicine and tissue engineering as targeted drug delivery devices because of their mechanical and physico-chemical properties. To control the rate of polymer degradation and drug release from polymer scaffolds, surface modification techniques are widely used. In this study, paracetamol-loaded poly (ε-caprolactone) electrospun fibrous scaffolds were treated by the pulsed electron beam irradiation. Pure control PCL scaffold, as well as scaffolds with four paracetamol concentrations (2 wt./wt. %, 8 wt./wt. %, 16 wt./wt. %, and 32 wt./wt.%) were modified. The mechanical and chemical properties and morphology of modified materials were examined. The sustained release of the model drug over a period of one hour for both non-treated and treated samples was demonstrated. It was shown that treatment leads to an increase in drug release rate and does not change surface morphology of scaffolds and fibers diameter distribution

Antibacterial ferroelectric hybrid membranes fabricated via electrospinning for wound healing

n the present study, wound healing ferroelectric membranes doped with zinc oxide nanoparticles were fabricated from vinylidene fluoride-tetrafluoroethylene copolymer and polyvinylpyrrolidone using the electrospinning technique. Five different ratios of vinylidene fluoride-tetrafluoroethylene to polyvinylpyrrolidone were used to control the properties of the membranes at a constant zinc oxide nanoparticle content. It was found that an increase of polyvinylpyrrolidone content leads to a decrease of the spinning solution conductivity and viscosity, causing a decrease of the average fiber diameter and reducing their strength and elongation. By means of X-ray diffraction and infrared spectroscopy, it was revealed that increased polyvinylpyrrolidone content leads to difficulty in crystallization of the vinylidene fluoride-tetrafluoroethylene copolymer in the ferroelectric β-phase in membranes. Changing the ratio of vinylidene fluoride-tetrafluoroethylene copolymer and polyvinylpyrrolidone with a constant content of zinc oxide nanoparticles is an effective approach to control the antibacterial properties of membranes towards Staphylococcus aureus. After carrying out in vivo experiments, we found that ferroelectric hybrid membranes, containing from five to ten mass percent of PVP, have the greatest wound-healing effect for the healing of purulent wound

A new approach for the immobilization of poly(acrylic) acid as a chemically reactive cross-linker on the surface of poly(lactic) acid-based biomaterials

A new approach for the immobilization of poly(acrylic) acid (PAA) as a chemically reactive cross-linker on the surface of poly(lactic) acid-based (PLA) biomaterials is described. The proposed technique includes non-covalent attachment of a PAA layer to the surface of PLA-based biomaterial via biomaterial surface treatment with solvent/non-solvent mixture followed by the entrapment of PAA from its solution. Surface morphology and wettability of the obtained PLA-PAA composite materials were investigated by AFM and the sitting drop method respectively. The amount of the carboxyl groups on the composites surface was determined by using the fluorescent compounds (2-(5-aminobenzo[d]oxazol-2-yl)phenol (ABO) and its acyl derivative N-(2-(2-hydroxyphenyl)benzo[d]oxazol-5-yl)acetamide (AcABO)). It was shown that it is possible to obtain PLA-PAA composites with various surface relief and tunable wettability (57°, 62° and 66°). The capacity of the created PAA layer could be varied from 1.5 nmol/cm2 to 0.1 μmol/cm2 depending on the modification conditions. Additionally, using bovine serum albumin (BSA) it was demonstrated that such composites could be modified with proteins with high binding density (around 0.18 nmol/cm2). Obtained fluoro-labeled PLA-PAA materials, as well as PLA-PAA composites themselves, are valuable since they can be used for biodegradable polymer implants tracking in living systems and as drug delivery systems

A new approach for the immobilization of poly(acrylic) acid as a chemically reactive cross-linker on the surface of poly(lactic) acid-based biomaterials

A new approach for the immobilization of poly(acrylic) acid (PAA) as a chemically reactive cross-linker on the surface of poly(lactic) acid-based (PLA) biomaterials is described. The proposed technique includes non-covalent attachment of a PAA layer to the surface of PLA-based biomaterial via biomaterial surface treatment with solvent/non-solvent mixture followed by the entrapment of PAA from its solution. Surface morphology and wettability of the obtained PLA-PAA composite materials were investigated by AFM and the sitting drop method respectively. The amount of the carboxyl groups on the composites surface was determined by using the fluorescent compounds (2-(5-aminobenzo[d]oxazol-2-yl)phenol (ABO) and its acyl derivative N-(2-(2-hydroxyphenyl)benzo[d]oxazol-5-yl)acetamide (AcABO)). It was shown that it is possible to obtain PLA-PAA composites with various surface relief and tunable wettability (57°, 62° and 66°). The capacity of the created PAA layer could be varied from 1.5 nmol/cm2 to 0.1 μmol/cm2 depending on the modification conditions. Additionally, using bovine serum albumin (BSA) it was demonstrated that such composites could be modified with proteins with high binding density (around 0.18 nmol/cm2). Obtained fluoro-labeled PLA-PAA materials, as well as PLA-PAA composites themselves, are valuable since they can be used for biodegradable polymer implants tracking in living systems and as drug delivery systems

Enhanced properties of poly(ε-caprolactone)/polyvinylpyrrolidone electrospun scaffolds fabricated using 1,1,1,3,3,3-hexafluoro-2-propanol

Poly(ε-caprolactone)/polyvinylpyrrolidone (PCL/PVP) scaffolds with various composition were fabricated from 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) solution using the same electrospinning parameters in order to reveal the effect of polymer ratio on the material properties. The obtained materials were characterized using scanning electron microscopy, contact angle measurements, X-ray diffraction, Fourier-transformed infrared spectroscopy, and tensile testing. The strengthening effect of PVP was observed: Young modulus of PCL/PVP scaffold with 50/50 polymer ratio was found at 105.4 ± 8.4 MPa which is six times higher comparing to those of PCL scaffold. PVP-containing scaffolds were extremely hydrophilic with PVP concentration of 5 wt% (vs. 25 wt% in previous reports) leading to full wetting of the material. in vitro studies showed an improved viability of HeLa cells cultured with the composites containing higher concentrations of PVP. Owing to the application of HFIP, PCL-based materials were loaded with cyclophosphamide for the first time and the PVP-containing materials demonstrated the intensified initial release of the model compound. Utilizing HFIP for the fabrication of PCL/PVP scaffolds significantly widens their application for drug delivery systems due to a good solubility of proteins, drugs, and other biologically active compounds in this solvent