Angiogenic Rg sub(1)/Sr-Doped TiO sub(2) Nanowire/Poly(Propylene Fumarate) Bone Cement Composites

• Published in: Macromolecular bioscience 2017-02, Vol.17 (2), p.np-np
• Main Authors: Salarian, Mehrnaz, Xu, William Z, Bohay, Richard, Lui, Edmund MK, Charpentier, Paul A
• Format: Article
• Language: English
• ISSN: 1616-5187; 1616-5195
• DOI: 10.1002/mabi.201600156

A new approach is provided for preparing radiopaque and angiogenic poly(propylene fumarate) (PPF) bone cements by integrating Sr-doped n-TiO sub(2) nanowires and ginsenoside Rg1 suitable for treating osteonecrosis. High aspect ratio radiopaque TiO sub(2)-nanowires are synthesized by strontium doping in supercritical CO sub(2) for the first time, showing a new phase, SrTiO sub(3). PPF is synthesized using a transesterification method by reacting diethyl fumarate and propylene glycol, then functionalized using maleic anhydride to produce terminal carboxyl groups, which are subsequently linked to the nanowires. The strong interfacial adhesion between functionalized PPF and nanowires is examined by scanning electron microscopy, Fourier transform infrared, X-ray photoelectron spectroscopy, thermal analysis, and mechanical testing. An angiogenic modulator, ginsenoside Rg sub(1), is integrated into the bone cement formulation with the mechanical properties, radiopacity, drug release, and angiogenesis behavior of the formed composites explored. The results show superior radiopacity and excellent release of ginsenoside Rg sub(1) in vitro, as well as a dose-dependent increase in the branching point numbers. The present study suggests this new methodology provides sufficient mechanical properties, radiopacity, and angiogenic activity to be suitable for cementation of necrotic bone. Angiogenic and radiopaque bone cement composites are synthesized by incorporating radiopaque Sr-doped TiO sub(2) nanowires into biodegradable poly(propylene fumarate) followed by integration of an angiogenic modulator, ginsenoside Rg sub(1). Sr-doped TiO sub(2) nanowires enable postoperative assessment using X-radiography while enhancing mechanical strengths. Gradual release of ginsenoside Rg sub(1) promotes the growth of blood vessels.