PHOSPHOLIPID ALKANETHIOL BILAYERS FOR CELL-SURFACE RECEPTOR STUDIES BY SURFACE-PLASMON RESONANCE

Supported hybrid bilayer membranes (HBM) composed of a monolayer of ph ospholipid and a monolayer of alkanethiol associated with a thin gold film on glass are useful as model lipid bilayer membranes for studying membrane receptor-ligand and cell-cell binding events by surface plas mon resonance (SPR). Measurements of specific binding of proteins and lipid vesicles to well-defined HBMs have been performed under conditio ns of continuous flow using a commercial SPR instrument (BIAcore). HBM s are shown to be stable in how and to block nonspecific adsorption of proteins to the alkanethiol/gold surface. The use of such supported l ipid bilayers in flow provides a means of conducting equilibrium and k inetic studies of models of ligand-cell and cell-cell interactions wit h receptors or ligands in a membrane environment. Compared to the exte nded dextran polymer layer that is currently used for surface modifica tion of BIAcore ''sensor chips,'' the described HBMs provide a well-de fined surface that will permit less ambiguous modeling of these import ant biological interactions. (C) 1995 Academic Press, Inc.