Adsorption study of pellicle proteins to gold, silica and titanium by quartz crystal microbalance method

Initial stage of biofilm formation is the adhesion of salivary pellicle proteins on the material surfaces. The aim of the present study was to evaluate the adsorption behaviors of saliva pellicle proteins onto a gold, silica and titanium by using the 27 MHz quartz crystal microbalance method. As pellicle proteins, lactoferrin, lysozyme, defensin and mucin were evaluated. Adsorption amount of lactoferrin to silica was significantly lower than gold and titanium. Significant differences were detected between titanium and silica for the adsorption amounts of lysozyme. Chemical bond formation of sulfur atom of lysozyme and gold could be suggested. There were no significant differences of the adsorption amount of β-defensin among each substrate. For mucin adsorption, gold showed the highest adsorption amount. It is presumed that electrostatic repulsion caused less adsorption amounts of mucin to titanium and silica. In conclusion, the differences of the adsorption behaviors of pellicle proteins could be clearly identified.