A variety of diseases are identified by protein markers. Nano-sized particles using metals such as gold and silver possess unique electronic and optical properties, which can be significantly altered when effected by an external cue, such as the interaction with a specific protein. Developing a fundamental understanding of nanoparticle-protein interactions and their associated optical properties is critical for the development of novel detection devices with high sensitivity and selectivity for detection of diseases, such as cancer and Alzheimer's. The knowledge obtained from this proposed research on nanoparticle-protein interactions will further assist in the development of novel technologies for the biomedical, materials, and energy sectors. This project connects researchers and resources at Howard University and Winston-Salem State University to integrate education and research training for students at the undergraduate and graduate levels. The project will provide rigorous training opportunities for the next generation of African-American and other students from underrepresented groups pursuing careers in Chemistry, Chemical Engineering, Physics and Mechanical Engineering. Results from the current and developing research on the nanoparticle-protein interactions, bio-simulations and biosensor design will be incorporated into workshops and classes, to expand the interests and experience of under-represented students in the STEM fields. This will promote successful academic and career paths.
Understanding the fundamental plasmonic response of gold and silver nanoparticles interacting with proteins is critical for molecular detection. This includes understanding the electronic properties and electromagnetic spectrum of discrete uniform gold and silver nanoparticles. This also includes understanding nanoparticle interactions with protein markers in a biochemical environment. The interactions of interest include physical and chemical coordination of the nanoparticles to the protein and the electromagnetic and plasmonic response from protein-nanoparticle interactions. The project will be achieved by coupling experimental spectroscopy with computational simulations at multiple scales (quantum, atomistic, molecular and continuum). The proposed study aims to elucidate different factors, including proteins' packing structure based on nanoparticles varying in type, shape, and means of surface functionalization. These fundamental nanoparticle-protein interactions will determine the plasmonic effect on electromagnetic and plasmonic signals. Simulations at the microscopic and macroscopic levels will provide knowledge on both the physical interactions and chemical reactions of nanoparticles and proteins, which are crucial for correlating nanoparticles' optic signals following environmental responses. Moreover, chemically modified nanoparticles' electronic structure, optical spectra, and magnetic properties will be studied using local surface plasmon resonance spectrum or surface enhanced Raman spectroscopy. These experimental results will be validated with quantum simulations. Subsequently, theoretical studies will more clearly explain spectrum signals and lead to improved experimental design of the target sensor. The multidisciplinary research team consists of experts in quantum and atomistic simulations, bio-nano interface, protein folding, experimental optical sensor design, and nanoparticle synthesis.
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.
