In SituMonitoring of Adsorption of Lysozyme onto Quartz Using an Electrode-Separated Piezoelectric Sensor☆

Abstract The adsorption of lysozyme from phosphate-buffered saline (pH 7.0) onto a quartz crystal interface was investigated in situ using an electrode-separated piezoelectric sensor (ESPS). Increasing amounts of lysozyme adsorbed onto a quartz crystal surface resulted in linearly decreasing oscillating frequencies of the ESPS. The lysozyme adsorbed is partially desorbed after rinsing with the phosphate-buffered saline. The amounts adsorbed reversibly and irreversibly were estimated. The influence of the surface roughness of the quartz crystal on the adsorption density measurement is discussed.