Non Toxic InP Quantum Dots for Luminescence Cellular Imaging and Sensing

University Of Maryland Baltimore County, Baltimore MD

Investigators

Abstract

AWARD ABSTRACTS CHE-1506995 Zeev Rosenzweig, Non Toxic InP Quantum Dots for Luminescence Cellular Imaging and Sensing PUBLIC ABSTRACT Luminescent semiconductor nanoparticles are materials with an extremely small diameter, about 10,000 times smaller than the diameter of a single human hair. Their small size gives them unique optical properties. When irradiated, they emit intense visible light in a color that depends on their size, shape and composition, making it possible to generate a rainbow of visible emission colors from a single semiconductor material. Luminescent semiconductor nanoparticles have found use in recent years in biomedical imaging and sensing applications, in light emitting devices including cell phone screens and flat screen TVs, and in energy converting photovoltaic devices. Their distribution across a wide range of economic sectors has raised serious health and environmental concerns since these nanomaterials often contain cadmium, a highly toxic substance. Zeev Rosenzweig, at UMBC is developing novel synthesis, and surface modification methods to prepare a new generation of cadmium-free, and therefore non-toxic luminescent semiconductor nanoparticles made of indium phosphide (InP). Rosenzweig and his students also demonstrate the utility of InP nanoparticles as cellular imaging agents to study how enzymes work in living cells. Dr. Rosenzweig is active in the recruitment of underrepresented minorities into STEM fields by partnering with the Interdisciplinary Consortium for Research and Educational Access in Science and Engineering (INCREASE). He also works with veterans to give them research experience and to contribute to their professional development. TECHNICAL ABSTRACT With this award, the Macromolecular, Supramolecular and Nanochemistry Program in the Chemistry Division is funding Professor Zeev Rosenzweig, of the University of Maryland Baltimore County (UMBC) Department of Chemistry and Biochemistry, to develop InP/ZnS core-shell semiconductor nanoparticles as an alternative to cadmium-containing quantum dots presently used for cellular fluorescence imaging. InP quantum dots, while non-toxic, currently have inferior photophysical properties and low chemical stability compared to cadmium-containing quantum dots. The objectives of these studies are to control the reaction conditions for InP (core) and InP/ZnS (core-shell) quantum dots formation using fluorescence lifetime spectroscopy measurements, to modify the surface of InP/ZnS in order to increase their chemical stability in the complex biological solutions, and to utilize them for quantitative imaging and sensing studies of key metabolic enzymes, phosphatases and protein kinases in living cells. The proposed multidisciplinary study impacts a number of scientific disciplines including chemistry, biochemistry, materials chemistry, polymer chemistry and environmental science and engineering. Dr. Rosenzweig is actively involved in student recruitment in collaboration with the national Interdisciplinary Consortium for Research and Educational Access in Science and Engineering (INCREASE) which focuses on bringing underrepresented groups into the STEM fields. In partnership with the UMBC Office of Student Veterans, he also serves as a mentor to UMBC student veterans to prepare them for professional careers in STEM and provide them with the opportunity to engage in this nanotechnology research project.