Dopamine is an important neurotransmitter that is responsible for transmitting signals between the neurons of the brain. The fluctuation of dopamine concentration can cause several neurological disorders including Parkinson's disease. Several analytical methods have been developed for the detection of dopamine. However, they are often time consuming, involve multistep reactions, and require expensive equipment. To date, there is a demand for the development of low-cost and user-friendly sensors for the detection of dopamine. The objective of the project is to develop a simple, rapid, and easy-to-use sensor platform for the detection of dopamine released from neurons under the stimulation of releasing agents. The sensor platform will use an optical probe composed of a nanotube structure known as "J-aggregate nanotube" integrated in polymer hydrogel sheets. The high sensitivity of the sensor platform for the detection of dopamine is a result of the highly efficient photoinduced electron transfer of J-aggregate nanotube probes. The project will provide research opportunities for training graduate and undergraduate students including the students from underrepresented groups in the interdisciplinary field of engineering, physical sciences and biology.
Photoinduced electron transfer is commonly used in designing optical probes for biosensor applications. The proposed research will focus on the synthesis of J-aggregate nanotubes with efficient photoinduced electron transfer characters and the integration of them into polymer hydrogel sheets to fabricate a simple and robust sensor platform for in situ detecting the release of dopamine from neurons stimulated by amyloid beta peptides. The approaches for achieving the goals of the proposed research includes the use of the co-assembly of bile acids and cyanine dyes with systemically varied chemical structures to form J-aggregate nanotubes, the characterization of the polarization behavior and the delocalized excitation length of J-aggregate nanotubes, the fabrication of J-aggregate nanotube integrated hydrogel sheets through the thermal-induced gelation of agarose solution with the nanotubes, the measurement of the sensitivity and selectivity of the sensor platform for the detection of dopamine in aqueous solution in the presence of interference species, and the in situ detection of the release of dopamine from neurons under the stimulation of amyloid beta peptides. The proposed research will aid the fundamental understanding of the formation mechanism and physical properties of J-aggregate nanotubes from the co-assembly of cyanine dyes and bile acids, which will open an opportunity to synthesize highly sensitive J-aggregate nanotube probes. The proposed sensor platform synergizing the features of both J-aggregate nanotubes and agarose hydrogels can be used to in situ detect the release of dopamine from neurons. The understanding of the release kinetics of dopamine from neurons stimulated by different releasing agents will provide the basis for the design of releasing agents and improve therapies for Parkinson?s disease.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
