CAREER: Plasmonics with a Twist - Chiral Nanostructures for Advanced Spectroscopy

University Of Maryland, College Park, College Park MD

Investigators

Abstract

TECHNICAL SUMMARY: The objective of this CAREER proposal is to improve the detection sensitivities of chiral molecular spectroscopy tools using the concept of plasmonic enhancement. Plasmonic nanostructures display unique optical properties that can be used to manipulate the propagation and polarization of light at a length-scale smaller than its wavelength. This research, sponsored by the Solid State and Materials Chemistry (SSMC) program, will experimentally and theoretically investigate the interactions between light, plasmons, and chiral molecules with the goal of achieving preferential optical excitation or scattering from one enantiomer over the other. The researchers will develop new fabrication methods for 3-dimensional nanoscale objects, model the polarization evolution in plasmonic systems, and demonstrate enhanced circular dichroism and optical activity in engineered metal nanoparticle-molecule complexes. Industrial collaborations will accelerate the technology transfer to pharmaceutical and analytical laboratories in industry. Undergraduate and graduate students at the University of Maryland will carry out the research activities and will be involved in outreach programs to generate excitement among the broad public towards scientific research. NON-TECHNICAL SUMMARY: Molecular "handedness", known as Chirality, is ubiquitous in Nature. The "handedness" of biomolecules leads to specific lock-and-key interactions that govern the way enzymes, receptors, DNA, RNA, etc. fold, assemble, interact and function. Mixtures of "left" and "right" chiral molecules are often unacceptable in medicinal products, as one isomer could be toxic while the other is therapeutic. The task of distinguishing between chiral molecules is not trivial, because they have the same physical and chemical properties. This project will use nanostructures with unique optical characteristics to increase the sensitivity of optical spectroscopy tools used to identify the "handedness" of biological products. These improvements will lead to higher standards in pharmaceutical product quality control, the generation of reference libraries of spectral signatures of biological products and pathogens, and better tools for the study of molecular conformations and their role in cellular regulatory functions and diseases (e.g. Alzheimer's and mad-cow). Integrated in this project is the scientific training of a diverse group of undergraduate and graduate students at the University of Maryland, outreach activities emphasizing student involvement in their communities, and the design of artistic displays illustrating unique optical properties of nanomaterials.