Preparation and examination of a scaffold based on hydroxylated polyphosphazene for tissue engineering: In vitro and in vivo studies

Abstract

In the current study, we introduced a new water‐soluble polyphosphazene containing hydroxyl groups, poly(propyleneglycol)phosphazene (PPGP). The PPGP is converted to PPGP‐TiO2 cross‐linked polymer via hydrothermal reaction with Ti(OBu)4. The properties of the obtained polymers were assessed by 1H‐NMR, 31P‐NMR, Fourier transform infrared spectroscopy (FTIR) and X‐ray diffraction (XRD) spectroscopic methods, thermal techniques (DSC‐TGA), FESEM–EDX investigations, cyclic voltammetry (CV) and Zeta potential measurements. In order to predict PPGP‐TiO2 cross‐linked polymer structure and obtain HOMO–LUMO maps and COMSO sigma profile, quantum calculations were used by DMol3 module based on Dispersion‐corrected density functional theory (DFT‐D) in Materials Studio Software2017. As a common bone substitute material, hydroxyapatite (HAp) was prepared using a modified method and closely characterized by appropriate analysis. The PPGP cytotoxicity was examined using C2C12 and L929 cell lines and Escherichia coli. The C2C12 differentiation using PPGP (as media supplement) was quantified by alkaline phosphatase activity assay. The biocompatibility of PPGP‐TiO2 was compared with HAp using mentioned cell lines and acute inflammatory testing. The results demonstrated that cell proliferation and osteoblastic differentiation increased in presence of PPGP. Both in vitro and in vivo evidence indicated that the novel scaffold had significant viability, exhibiting notable adaptability with its surrounding living tissue.

Fabrication and examination of polyorganophosphazene/polycaprolactone-based scaffold with degradation, in vitro and in vivo behaviors suitable for tissue engineering applications

“…For synthesize of poly(propyleneglycol)phosphazene- graft -polycaprolactone (PPGP- g -PCL), we produced the phosphazene random polymer carrying terminal alcohol functions, labeled with PPGP, as the water-soluble precursor 26 . Grafting of PCL was conducted via ROP of ε -CL in present Zn(AC) 2 .2H 2 O catalyzer by pendant hydroxyl groups of the PPGP precursor as multisite macroinitiator 27 .…”

Cyclo- and Polyphosphazenes for Biomedical Applications

“…Collagen I and calcium deposition occurred, likely due to the higher amounts of ions attracted together with the activation of voltage-gated Ca 2+ channels on cell membranes, thus increasing the level of intracellular Ca 2+ and thus promoting osteogenesis [ 221 ]. A biocompatible composite able to induce cell proliferation and osteoblastic differentiation has been achieved by the hydrothermal crosslinking of water-soluble phosphazene containing hydroxy groups and Ti(OBu) 4 , as seen in Scheme 15 [ 222 ].…”

Piezoelectric approaches to organic polymeric materials

“…Poly(vinyl alcohol), a water‐soluble polymer, is also used in biosensors and drug delivery systems because of its biocompatibility and ability to respond to humidity changes 47,54 . Polyimide, a high‐performance polymer, exhibits excellent piezoelectric properties and is used in high‐temperature sensors and actuators due to its high thermal stability, 55–58 while polyphosphazene, another biocompatible piezoelectric polymer, is used for biomedical applications such as tissue engineering and drug delivery 59,60 . A whole array of polymers is being studied today, and piezoelectric characterization plays a pivotal role in realizing their potential industrial applications.…”