Biomaterials Volume 29, Issue 28, October 2008

Biodegradable injectable polyurethanes: Synthesis and evaluation for orthopaedic applications

Raju Adhikari^{a, ,} , Pathiraja A. Gunatillake^a, Ian Griffiths^a, Lisa Tatai^a, Malsha Wickramaratna^b, Shadi Houshyar^a, Tim Moore^a, Roshan T.M. Mayadunne^b, John Field^c, Margaret McGee^d and Tania Carbone^d

--------------------------------------------------------------------------

Synthesis and characterization of biodegradable elastomeric polyurethane scaffolds fabricated by the inkjet technique

Changhong Zhang^a, Xuejun Wen^a, Naren R. Vyavahare^a and Thomas Boland^{, a,}

Fig. 7. Photograph of the patterns printed on glass slides by inkjet printing technique. A 50% (V/V) acetic acid water solution in HP 21 cartridge was printed out by one pass on MP530B solution coated glass slide. Patterns immediately formed in 1 s after printing. (A) Separate letters printed on the stand glass slides; (B) contacted O-rings printed on the standard glass slides. All the patterns were computer designed by Microsoft Office software. The letters fixed on the right side of the standard glass slides were used as size control; (C) schematic diagram shows that MP530B in the solution was neutralized and became soluble with pH higher than 8.7, this reaction is revisable with solution pH value adjusted lower than 8.7. This reaction was utilized for the scaffold fabrication by inkjet printer.

Fig. 8. SEM images of the PU scaffold showing, (A) and (B) primary structures at different magnifications show the porous structure with pore size ranging from 10 μm to 30 μm. (C) Secondary structure shows the porous structure with uniform and inter-connective pores, the average size of pores is less than 1 μm. (A) Magnification 400×, (B) magnification 2500×, (C) magnification 20,000×.