Viscoelastic adlayers of collagen and lysozyme studied using quartz crystal microbalance with dissipation monitoring.
In this study the effects of molecular structure of proteins on their adsorption behaviour and viscoelasticity are investigated using a QCM-D method. The adsorption measurements show that spherical lysozyme is rapidly adsorbed on the gold surface as a stiff monolayer, as indicated by a sharp drop in the oscillation frequency (Deltaf) of the sensor, and by a very small increase in the energy dissipation of the adlayer (DeltaD). Fibrous calfskin collagen (CSC) is, however, adsorbed on the same surface rather slowly in two steps to form a thick and soft multilayer (large Deltaf and DeltaD) at pH 3 in salt-free conditions. The two-step adsorption is not observed for stiffly aggregated CSC. This study clearly demonstrates that the polymer structure strongly affects not only how adsorption develops but also the viscoelastic properties of the adlayer.
Department of Dental Materials Science and Technology, Iwate Medical University School of Dentistry, Morioka, Japan. tnezu@iwate-med.ac.jp
Takashi
T
Nezu
Masayuki
M
Taira
Setsuo
S
Saitoh
Kaori
K
Sasaki
Yoshima
Y
Araki
D000327:Adsorption; D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D003094:Collagen / Q000737:chemistry* / Q000378:metabolism; D004548:Elasticity; D006046:Gold / Q000737:chemistry; D009113:Muramidase / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D011791:Quartz / Q000737:chemistry*; D012212:Rheology; D013499:Surface Properties; D014783:Viscosity
D011791:Quartz; D006046:Gold; D003094:Collagen; D009113:Muramidase