Degradation of Polyphosphazenes Developed for Tissue Engineering

Singh and co-workers systematically investigated the role of amino acids as side groups in polyphosphazenes with respect to their degradation behaviour. For this purpose, they synthesised four different 

for polymer 2 could not be recorded beyond 3 weeks due to rapid hydrolysis, b) mass loss recorded for polymers 1-4 in PBS solution at 37 °C. Reproduced with permission from A. Sing, N.R. Krogman, S. Sethuraman, L.S. Nair, 

In several publications, a number of variations of polyphosphazenes in terms of different side groups have been demonstrated to be applicable for TE. The desired scaffolds can be fabricated in different appropriate formats such as 2D objects, e.g., films and membranes, or in the form of 3D matrices. A few examples of cell types are described in the literature, which have been used for TE on polyphosphazene scaffolds, like osteoblasts, EC or Schwann cells. Most of the polyphosphazenes appear to be quite compatible with the cells they are intended to support in terms of adhesion and proliferation, they can be degradable and with careful design, the degradation products tend to be toxicologically harmless. It can be expected that some future implanted bones, blood vessels or even nerves will have been made based on tailored, highly advanced polyphosphazenes. 

Krogman in Polyphosphazenes for Advanced Biomedical Applications, Pennsylvania State University, PA, USA, 2008. [PhD Dissertation] 

Ruokolainen, Journal of Polymer Science Part B Polymer Physics Edition, 2013, 51, 1318. 

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