Supramolecular-based Fluorescent Sensors and Surfactants

点击翻译按钮获取中文摘要

Supramolecular chemistry, or "chemistry beyond the molecule", involves structures consisting of two or more molecules held together by weak forces of attraction as opposed to chemical bonds. A simple example of a supramolecular system is a host-guest inclusion complex, in which a guest molecule becomes included within the cavity of a larger, cage-like organic host molecule (like a ball in a bucket). The most common family of host molecules are the cyclodextrins (CDs), cyclic forms of glucose sugar that take on a bucket-like shape in water, and strongly bind guest molecules inside their internal cavities. Building upon the previous success in my research group involving fluorescence-based investigations of the fundamental properties of host-guest inclusion systems, the transformative research to be supported by this proposal involves the novel application of such supramolecular systems in two important areas: 1) molecular sensing and 2) supramolecular surfactants and micelles for molecular delivery. Molecular sensing involves the detection and measurement of specific target molecules, such as organic environmental pollutants; three such projects are proposed. First, the rational design of chemically modified CDs will be undertaken to obtain hosts with targeted binding properties, to serve as sensors for specific guests of interest. Second, the potential for fluorescent signal enhancement in non-aqueous solutions will be explored, to extend the use of supramolecular-based sensors beyond water solutions. This part of the study will include fundamental investigations into the currently understudied phenomena of host-guest inclusion occurring in non-aqueous media. Third, the potential application of two fluorescent, uniquely-shaped hosts as fluorescent sensors will be explored. In molecular delivery, a specific molecule of interest, such as a drug, is encapsulated or attached to a molecular system, transported to the area of interest, such as a tumor, and released to act upon the target area. A specific molecular delivery project is proposed, involving the design and synthesis of supramolecular host-guest surfactants, which can form micelles or vesicles, large cell-like molecular structures which can incorporate drug molecules, and which can be triggered to disrupt to release the drug at a target site. Thus this project involves a balanced combination of fundamental and targeted, applied research.