Rapid, on-site detection of biomolecules is critical for the biomedical industry, environmental monitoring, food safety and quality. As such, there is a constant demand for novel high performance sensor technologies, capable of detecting many target biomolecules within small sample volume at a reduced cost. This research project will aid in addressing societal needs for robust and sensitive biosensors which are low-cost, readily manufacturable, and are able to sense many biomolecules at a time. A sensitive, fiber-based optical platform in which a change in emitted light wavelength signals the presence and amount of the target biomolecule will be used. Within this platform, multiple sensors will be integrated into a small area to create high density biosensor array which can concurrently detect multiple biomolecules from the same small sample volume. Biorecognition elements, which interact with the target biomolecules allowing them to be detected, will be directly integrated into each individual sensor using a simple and scalable, one-step approach. The incorporation of biorecognition elements into the fiber-based sensors will further facilitate sensing of multiple biomolecules while maintaining a small footprint and minimal sample volume. This research project will provide support for a number of mentoring and outreach activities designed to inspire, recruit, and train a diverse set of future scientists and engineers. The investigators' endeavors will benefit the education of graduate, undergraduate, and middle school students.
The objective of this research project is to demonstrate and develop an electrospun whispering gallery mode resonators with integrated phage-based recognition elements as robust, highly-sensitive multiplexed optical biosensors. With near circular cross-sections and controlled microscale diameters, electrospun fibers are excellent candidates for low-cost, readily manufacturable whispering gallery mode resonators. Moreover, these simple, compact optical devices will allow several cavities with distinct optical signatures to be placed within a small area to be used for biomolecule assays or multiplexed sensing. Electrospinning is well-suited to incorporate biorecognition elements such as filamentous phage within the optical cavity at high concentrations. Phage-based bioreceptors provide a high density of well-organized and highly-oriented analyte binding sites for high sensitivity detection. Phages are chemically and thermally robust, tolerating a range of sensing conditions and can be manufactured inexpensively in large quantities with a bacterial host. The integration of bioreceptors into the whispering gallery mode optical cavity will eliminate the need for biofunctionalization steps following cavity fabrication, thus minimizing manufacturing complexity, reducing biosensor footprint, and enabling straightforward multiple analyte detection. Furthermore, the unsurpassed density of highly-oriented bioreceptors associated with the filamentous phage, as well as the long- and short-range ordering created by the electrospun scaffold is expected to produce biosensors with unparalleled sensitivity and selectivity.