The wide use of magnesium and magnesium-based alloys for bio-implant materials has so far been restricted due to the rapid corrosion rate of such materials under in-vivo conditions ^1,2. Cellulose based coatings have previously been examined as coatings for magnesium materials although the use of TEMPO-oxidised nano-fibrillated cellulose (CNF-TEMPO) coatings has yet to be explored ^3,4. The work outlines details of an investigation in to the effect that deposition method has on the coating characteristics. Three different methods were used to deposit CNF-TEMPO coatings including adsorption, spin coating and anodic electrophoretic deposition. The coatings were subsequent analysed using atomic force microscopy (AFM), ellipsometry and quartz crystal microbalance (QCM) to determine differences in nanotopographic surface roughness and hydrophilicity in particular. The ability of the EPD technique to deposit films from relative dilute solutions (0.01 to 0.1 wt-%) was demonstrated. Finally, samples of magnesium were coated and the corrosion properties of the ultrathin films were determined using a number of electrochemical techniques including linear sweep voltammetry, polarization and free corrosion measurements. Overall, the results show that CNF-TEMPO coatings produced using the EPD method offer a potential starting point for the next generation of biobased coatings for implant materials.

References

[1] S. Virtanen, Mater. Sci. Eng. B, 2011, 176, 1600-1608

[2] F. Witte, N. Hort, C. Vogt, S. Cohen, K. U. Kainer, R. Willumeit, F. Feyerabend, Current Opinion in Solid State and Materials Science, 2008, 12, 63-72.

[3] S. Heise, S. Virtanen, A. R. Boccaccini, Journal of Biomedical Materials Research A, 2016 104A, 2628-2641.

[4] K. Yliniemi, B. P. Wilson, F. Singer, S. Höhn, E. Kontturi S. Virtanen, ACS Applied Materials and Interfaces, 2014, 6, 22393-22399.