Development of an Electroactive Fiber-Optic Chip for Optical/Electrochemical Characterization of Planar-Supported Biological Materials

University Of Louisville Research Foundation Inc, Louisville KY

Investigators

Abstract

This award supports development of a new, fiber-optic-based instrument which will permit broadband, highly sensitive spectro/electrochemical characterization of substrate-supported biomolecular films, including membrane-bound proteins and their electroactive constituents. The proposed instrumentation is based on a new electroactive fiber-optic chip (EA-FOC) that can provide: 1) ultra-sensitive absorbance and fluorescence characterization of surface-confined and membrane-bound biologically relevant molecules, 2) spectro/electrochemical (voltammetric, amperometric or potentiometric) characterization of proteins at microliter cell volumes and using 10-100 femtomoles of surface-confined redox reagent; 3) fluorescence detection of changes in the environment of signaling molecules that occur during ion transport through membrane assemblies. The instrument will make accessible, for the first time, the sensitivity enhancements of integrated optic waveguide and electroactive integrated optic waveguide (EA-IOW) technologies combined with the ease-of-use of fiber-optic based spectrophotometers. The planned effort extends previous work of the PIs to permit detection of changes in the structure and activity of membrane-bound biomolecules and increase the range of applications. The instrument will be able to study surface-confined optical/electrochemical events in biomolecular films of increasing architectural complexity, culminating with studies of membrane proteins reconstituted into planar supported lipid bilayers. The final design of the EA-FOC is expected to provide a platform that can be integrated with a wide range of commercially available instrumentation, and will provide opportunities for the development of versatile, sensitive, and selective bio- and chemical sensor platform. Students directly involved in the project will be trained in the design, fabrication, characterization, and testing of new instrumentation, and will acquire an in-depth experience in several aspects of spectro/electrochemistry techniques, optical fiber technologies, and optical spectroscopies, and in the application of those tools into studies of biomolecular films.