Integrated optical biosensor for detection of multivalent proteins

We have developed a simple, highly sensitive and specific optical waveguide sensor for the detection of multivalent proteins. The optical biosensor is based on optically tagged glycolipid receptors embedded within a fluid pho spholipid bilayer membrane formed upon the surface of a planar optical wave guide. Binding of multivalent cholera toxin triggers a fluorescence resonan ce energy transfer that results in;a two-color optical change that is monit ored by measurement of emitted luminescence above the waveguide surface. Th e sensor approach is highly sensitive and specific and requires no addition al reagents and washing steps. Demonstration of protein-receptor recognitio n by use of planar optical waveguides provides a path forward for the devel opment of fieldable miniaturized biosensor arrays. (C) 1999 Optical Society of America.