Physical characteristics of poly (vinyl alcohol) solutions in relation to electrospun nanofiber formation

Critical attributes of nanofibers: Preparation, drug loading, and tissue regeneration

“…According to the literature, there is no general rule for selecting the optimal polymer concentration because it depends on polymer and solvent characteristics. For example, in the case of PEO optimal concentration is 3% (w/w) (Rošic et al, 2012a) and in the case of PVA it is between 8 and 12% (w/w) (Rošic et al, 2013). According to Gupta et al, polymer solutions can be divided into three groups based on their c/c* ratio (where c is the polymer concentration and c* is the polymer concentration at which overlapping occurs between polymer chains): (I) dilute (c/c* = 1), (II) semi-dilute unentangled (1 < c/c* < 2), and (III) semi dilute entangled (c/c* > 2).…”

“…(Rošic et al, 2013). Discontinuous beaded fibers and elongated beads are known to appear when electrospinning a solution with a low polymer concentration.…”

“…The polymer dispersion viscosity is an important production parameter that is mainly a function of the polymer concentration; however, it is also affected by solvent properties because polymer-solvent and polymer-polymer interactions depend on the solvent used (Zhang et al, 2002). Furthermore, solvents decisively affect the surface tension and conductivity of the polymer dispersion, which is also affected by the polymer nature and concentration (Reneker and Chun, 1996;Rošic et al, 2013). Due to its safety and biocompatibility, water is the most desirable solvent; however, its use is limited to hydrophilic polymers (Bhardwaj and Kundu, 2010).…”

Stability and solubility of trans-resveratrol are strongly influenced by pH and temperature

“…The electrospinning was conducted at 15 kV, nozzle-to-planar collector distance 15 cm, and solution flow rate 1.3-2.5 mL/h resulted in nanofiber mats. The nanofiber morphology was examined using a 235 Supra 35VP-24-13 high-resolution scanning electron microscope (SEM) (Carl Zeiss,Germany) as described by Rošic [29]. of the dissolution medium were withdrawn, filtered, and immediately analyzed.…”

Photocrosslinked Poly(vinyl alcohol) Nanofibrous Scaffolds

“…However, many skin substitutes for grafts have been restrictively employed due to their disadvantages such as high cost, the limited availability of self skin grafts, and problems of immune response and disease transmission [1][2][3]. To deal with it, many tissue engineered skin substitutes get developed, among which nanofiber matrices have shown tremendous promise, attributed to their unique properties such as oxygen-permeable high porosity, variable pore-size distribution, high surface to volume ratio and more importantly, morphological similarity to natural extracellular matrix in skin, which promote cell adhesion migration and proliferation [4][5][6]. As a simple and versatile technique to fabricate these ultrafine fibers, electrospinning, have made many polymers including synthetic and natural polymers directly into nanofibers as potential wound dressing [7][8][9].…”