Competitive adsorption of human serum albumin and gamma-globulin from a binary protein mixture onto hexadecyltrichlorosilane coated glass.
The kinetics of competitive adsorption of proteins onto hexadecyltrichlorosilane coated glass (HTS-glass) from model solutions containing fluorescein isothiocyanate (FITC)-labeled human serum albumin (HSA-FITC) and gamma-globulin (HGG-FITC) were studied by total internal reflection fluorescence (TIRF) spectroscopy. The processes of displacement of HSA-FITC by HGG are independent of the conformational state of HSA adsorbed onto glass. On HTS-glass, displacement of protein is hindered by the presence of large numbers of CH3-terminated alkyl tails which induce conformational (reorientational) changes in HSA-FITC and HGG-FITC adsorbed from simple solutions. In contrast to HSA, adsorption of HGG onto HTS-glass from a simple solution is characterized by the absence of irreversible adsorption in the initial portion of the kinetic curve. Competition between HSA and HGG-FITC induces replacement of end-on adsorbed HGG-FITC on HTS-glass surface with subsequent desorption of the HGG-FITC into solution. Upon further increase in the HSA concentration in solution the competition of HSA for adsorption sites prevails, which leads to a decrease in the amount of adsorbed HGG-FITC and, consequently, to a decrease in the rate of its displacement.
Tremsina
Y S
YS
Russian Research Center for Blood Compatible Biomaterials, Institute of Transplantology and Artificial Organs, Moscow.
Sevastianov
V I
VI
Petrash
S
S
Dando
W
W
Foster
M D
MD
D000327:Adsorption; D016650:Fluorescein-5-isothiocyanate; D005898:Glass / Q000737:chemistry; D007700:Kinetics; D011487:Protein Conformation; D012709:Serum Albumin / Q000737:chemistry* / Q000502:physiology; D012821:Silanes / Q000737:chemistry* / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D013499:Surface Properties; D005719:gamma-Globulins / Q000737:chemistry* / Q000502:physiology
D012709:Serum Albumin; D012821:Silanes; D005719:gamma-Globulins; C111518:hexadecyltrichlorosilane; D016650:Fluorescein-5-isothiocyanate