Effects of pH, potential, and deposition time on the durability of collagen electrodeposited to titanium

Collagen is expected to work as a bonding agent of soft and hard tissues to solid materials. In this study, the electrodeposition of collagen to a titanium (Ti) surface under various conditions, i.e., the pH of the collagen solution, potential, and electrodeposition time, was performed to understand the optimal electrodeposition conditions for the immobilization of collagen to Ti. The effects of these conditions on the thickness and residual ratio of the collagen layer after shaking in water were evaluated by ellipsometry, scanning probe microscopy, and X-ray photoelectron spectroscopy. Collagen molecules were attracted to Ti cathode and immobilized with high durability by combining electrodeposition conditions, pH 5, alternating potential between -1V and +1V vs. SCE with 1 Hz, and 1800 s. The surface of this electrodeposited collagen layer was smooth and uniform maintaining the collagen fibril and natural structure. On the other hand, the collagen layer immobilized by immersion technique in a collagen solution, was rough and irregular. Electrodeposition with alternating potential at pH 5 for 1800 s is a much more appropriate technique to immobilize collagen to Ti than the conventional immersion technique.