Integrated optical biosensor for detection of multivalent proteins

Abstract

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 phospholipid bilayer membrane formed upon the surface of a planar optical waveguide. Binding of multivalent cholera toxin triggers a fluorescence resonance energy transfer that results in a two-color optical change that is monitored by measurement of emitted luminescence above the waveguide surface. The sensor approach is highly sensitive and specific and requires no additional reagents and washing steps. Demonstration of protein-receptor recognition by use of planar optical waveguides provides a path forward for the development of fieldable miniaturized biosensor arrays.

Biosensors Based on Biological Nanostructures

“…These methods present the important advantage of enabling the monitoring of single ion channel events, as shown by Cheng et al (Cheng, Bushby et al, 2001). Nevertheless, not much is known about the stability of these systems and this is a matter of concern, since earlier studies (Song e Swanson, 1999) showed that bilayers applied as matrices for optical sensors are unstable when directly attached to glass substrates for optical waveguide applications (Kelly, Grace et al, 1999;Song, Shi et al, 2000). A way to reduce the damaging effects of the substrate on the stability of the lipid bilayer is to use layers based on a protein linker that act as spacer layers between the substrate and the resultant bilayer, as proposed by Worsfold et al Fluorescence anisotropy can be used as a sensing technique due to its capability of providing a response to target binding by recording the change of rotational mobility of the fluorescent marker.…”

Multiplexed optical pathogen detection with lab‐on‐a‐chip devices

“…The use of so-called single mode planar optical waveguides has emerged as a powerful tool in fluorescence-based pathogen sensors [75][76][77][78][79]. These are structurally simple devices comprising a high index dielectric layer on a low-index substrate.…”

Planar optical waveguide-based biosensor for the quantitative detection of tumor markers

“…Since medical samples can contain many fluorescent constituents, this spatial filtering greatly reduces auto-fluorescence due to the background matrix. Both phospholipid bilayers [23,36] and self-assembled monolayers [24] can be used to functionalize the waveguide surface. The attachment of lipid bilayers to silica surfaces is well documented [37].…”