Characterization of adsorption of glycine on gold and titanium electrodes using electrochemical quartz crystal microbalance

Abstract

The adsorption of the simplest amino acid, glycine, on gold and titanium surfaces in Hanks’ solution was monitored using the quartz crystal microbalance. The changes in mass and open circuit potential at rest potential and mass and current at constant potentials were measured before and after the injection of glycine. Results showed a momentary adsorption of glycine, followed by the desorption of a part of glycine adsorbed. The adsorbed amount of glycine increased with the increase of glycine concentration. The time before stabilizing the adsorption–desorption phenomena also increased with the concentration. More glycine was adsorbed on titanium than on gold because of the difference in the surface electric charges. The adsorption was accelerated by the charge of potential.