Singlet Oxygen-Responsive Fluorescent Nanomaterials

Tufts University, Medford MA

Investigators

Abstract

This project is funded by the Chemical Measurement and Imaging Program of the Chemistry Division at the National Science Foundation. Professors Samuel Thomas and Charles Mace of Tufts University, together with Professor Rajesh Menon of the University of Utah, are developing several new types of light-emitting nano-sized materials that respond to the molecule singlet oxygen. Singlet oxygen is an important molecule in light-driven processes such as photodynamic therapy and damage to plants upon overexposure to sunlight. One important outcome of this research is improved detection of singlet oxygen. Another important outcome of this research is better fundamental understanding of how the composition of fluorescent nano-sized materials affect their light emission properties and detection performance. This is important for other applications of light-emitting nano-sized materials. The broader impacts of this work include societal benefit from improved performance and reliability of analytical measurements involving fluorescent nanomaterials, and improved active learning of students in organic chemistry courses at Tufts University through a Peer-Led Team Learning (PLTL) pilot. The goal of this proposal is to understand how the compositions of different fluorescent nanomaterials influence their response to singlet oxygen and yield generally applicable comparisons of key characteristics such as energy transfer efficiency, as well as improvements to the unsolved problems of singlet oxygen sensing and imaging. The objectives of this proposal are: 1) Prepare and characterize the fluorescence spectroscopy and energy transfer characteristics of three classes of water-dispersible singlet oxygen-reactive nanomaterials?i) conjugated polymer nanoparticles, ii) quantum dots, and iii) block copolymer micelles, and 2) In collaboration between PIs at Tufts and University of Utah, determine how the classes and compositions of these nanomaterials affect performance in: i) singlet oxygen detection, ii) use of singlet oxygen as a secondary analyte in bioassays, and iii) photoactivated fluorescence.