Biotechnologie et biomatériaux

Abstrait

A Novel Electrophoretic Deposition Device: Effects of Alginate Viscosity Grade on Deposition Kinetics

Chris R Jackson, Pavan MV Raja and Satya Prakash

A novel device was designed to perform electrophoretic deposition under tightly controlled conditions. The device physical parameters were investigated by depositing three different viscosity grades of sodium alginate hydrogels. A thin metallic rectangular substrate was used to obtain the various time dependant deposition rates of the gels. The resulting deposition curves showed the effective electrophoretic mobilities of the low, medium and high viscosity grade gels were 0.0610 cm2/Vs, 0.0584 cm2/Vs and 0.0909 cm2/V sand that the ratios of gel deposit to solution resistivities were 21.0, 16.2 and 47.5 respectively. Following electrophoretic deposition, the gels were cross-linked in a 0.1 M CaCl2 solution in order to further solidify the gels. Cross-linking reduced the masses of the gels to 50.9 ± 1.8%, 26.7 ± 2.0%, and 28.5 ± 1.3% of their initial masses respectively. Lyophilization was applied to the gels to determine the alginate content of the gels. Immediately after deposition the alginate mass fractions of the low, medium and high viscosity grade gels were 2.92 ± 0.49%, 2.70 ± 0.08% and 2.94 ± 0.15% respectively. Cross-linking caused the mass fraction of alginate to increase significantly to 5.59 ± 0.07%, 7.11 ± 0.37% and 7.02 ± 0.24% respectively. The device in this study provided sufficient data to model the electrophoretic deposition rates. The technique can be expanded to other hydrogel species which can be used in a variety of biomedical and biotechnological applications.