Fabrication and Optimization of Methylphenoxy Substituted Polyphosphazene Nanofibers for Biomedical Applications

Abstract

Electrospinning has developed as a unique and versatile process to fabricate ultrathin fibers in the form of nonwoven meshes or as oriented arrays from a variety of polymers. The very small dimension of these fibers can generate a high surface area, which makes them potential candidates for various biomedical and industrial applications. The objective of the present study was to develop nanofibers from polyphosphazenes, a class of inorganic-organic polymers known for high biocompatibility, high-temperature stability, and low-temperature flexibility. Specifically, we evaluated the feasibility of developing bead-free nonwoven nanofiber mesh from poly[bis(p-methylphenoxy)phosphazene] (PNmPh) by electrospinning. The effect of process parameters such as nature of solvent, concentration of the polymer solution, effect of needle diameter, and applied potential on the diameter and morphology (beaded or bead-free) of resulting nanofibers were investigated. It was found that solution of PNmPh in chloroform at a concentration range of 7% (wt/v) to 9% (wt/v) can be readily electrospun to form bead-free fibers at room temperature. The mean diameter of the fibers obtained under optimized spinning condition was found to be approximately 1.2 microm. The bead-free, cylindrical nanofibers formed under the optimized condition showed a slightly irregular surface topography with indentations of a few nanometer scale. Further, the electrospun nanofiber mats supported the adhesion of bovine coronary artery endothelial cells (BCAEC) as well as promoted the adhesion and proliferation of osteoblast like MC3T3-E1 cells.

Water Soluble Polymers for Pharmaceutical Applications

“…Substitution of these chloride groups gives multifunctional polyphosphazenes with tunable physicochemical and biological properties [105]. These polymers have been used to formulate nano-fibers [106] and hydrogels [107]. Zhang et al have synthesized and developed thermally sensitive amphiphilic phosphazenes for sustained local delivery [108,109].…”

Biodegradable Nanomats Produced by Electrospinning: Expanding Multifunctionality and Potential for Tissue Engineering

“…Synthetic polymers Poly(DL-lactide) 10 20 Poly(L-lactide) 10 Poly(ethylene glycol)-poly(DL-lactide) diblock copolymer 10 36 Poly(ethylene oxide) 145 Poly[bis(methylphenoxy)phosphazene] 131 Poly(vinyl alcohol) coated Poly(p-xylylene) 125 Poly(ethylene-co-vinyl alcohol)…”

Development of Biodegradable Polyphosphazene- Nanohydroxyapatite Composite Nanofibers Via Electrospinning

“…We have recently demonstrated the fabrication of nanofibrous matrices from a novel class of polymer called polyphosphazene as potential candidate for tissue engineering applications [5,7]. Polyphosphazenes are polymers with an inorganic backbone of phosphorus and nitrogen atoms with two side groups attached to the phosphorus atom.…”

“…Among these, the process of electrospinning seems to be very promising due to the ease of fabrication, reproducibility, control over the process and comparatively lower cost [6]. In electrospinning, a polymer solution of suitable viscosity is subjected to an intense electrical potential which then undergoes a bending instability to afford fibers having diameter in the nanometer range.We have recently demonstrated the fabrication of nanofibrous matrices from a novel class of polymer called polyphosphazene as potential candidate for tissue engineering applications [5,7]. Polyphosphazenes are polymers with an inorganic backbone of phosphorus and nitrogen atoms with two side groups attached to the phosphorus atom.…”