PROTEIN ADSORPTION ONTO HYDROXYAPATITE THIN FILMS WITH QCM MEASURMENTS

Adsorptive properties of hydroxyapatite (HAp) for proteins were studied by Quartz Crystal Microbalance (QCM) method. The time-series reactions of HAp thin films to acidic and basic proteins were analyzed in various pH buffers by the simultaneous resonant frequency and dissipation factor measurements. The amorphous calcium phosphate thin films deposited on the Au-electrode of quartz crystals by rf-magnetron sputtering were transformed into the polycrystalline HAp films by post-annealing treatment in hydrothermal atmosphere. Adsorbate solution was continuously injected by a tube pump at controlled flow rates into the QCM cell equipped with a PC added measurement system. The difference in adsorption for albumin and histone was detected from their resonant frequency shifts. It was suggested that the developed QCM system was effective for studies on protein adsorption behaviors onto HAp.