AVS 46th International Symposium
    Surface Science Division Thursday Sessions
       Session SS3+BI-ThA

Invited Paper SS3+BI-ThA5
Quantitative Analyses of Biological Interactions using Surface-Biofunctionalized Surface Plasmon Resonance Devices

Thursday, October 28, 1999, 3:20 pm, Room 613/614

Session: Biological Surface Science
Presenter: C.T. Campbell, University of Washington
Authors: C.T. Campbell, University of Washington
L.S. Jung, University of Washington
J. Shumaker-Parry, University of Washington
K.E. Nelson, University of Washington
P.S. Stayton, University of Washington
M.S. Boeckl, University of Washington
M.H. Gelb, University of Washington
S.S. Yee, University of Washington
T. Sasaki, University of Washington
R. Aebersold, University of Washington
Correspondent: Click to Email
The adsorption of molecules from liquid solutions onto solid surfaces can be monitored with high sensitivity and fast time response by following changes in the angle or wavelength at which the surface plasmon resonance (SPR) of a thin metal film is optically excited. Simple methods convert these measured changes into adsorbate concentrations. We report here the adsorption and desorption kinetics and equilibrium coverages of a variety of species on well-characterized surfaces as determined by SPR techniques. When the diffusion constant of the adsorbing species is known in the liquid phase, the intrinsic rate constants can be determined from the kinetic results. A new method will be described for converting intrinsic adsorption rate constants into sticking probabilities (i.e., the probability that adsorption occurs, given a collision of the molecule with the surface). Several applications of gold-thin-film SPR sensors in quantifying biological interactions will be described. A gold surface containing a few biotin headgroups in a self assembled alkylthiol monolayer of mainly oligo(ethylene glycol) headgroups has been used to assess the effects of protein mutations on the strength of biotin-streptavidin binding. With wild-type streptavidin, the free biotin sites in the resulting streptavidin monolayer have been used as strong linker sites for further attachment of intact, biotinylated lipid vesicles and biotinylated, double-stranded oligonucleotides to the surface. These complex biological films then provide a surface template that can be used to probe the kinetics and equilibrium binding constants for: (1) peripheral membrane proteins binding to vesicle walls, and (2) the binding of DNA-binding proteins to select oligonucleotide sequences.