Understanding how molecules interact with each other to form stable assemblies is of fundamental scientific interest and has potential applications in fields as diverse as drug development, targeting and delivery, novel responsive/intelligent materials, and the development of new sensors. In this context, the formation of host-guest complexes, in which a large container molecule (the host) provides a welcoming space for the docking of a smaller molecule (the guest), is of great importance. Professor Angel E. Kaifer of the University of Miami is supported by the Macromolecular, Supramolecular and Nanochemistry Program at NSF to study the formation of host-guest complexes by an important class of hosts, known as the cucurbiturils. This project provides research opportunities to graduate, undergraduate, and high school students (including women and members of underrepresented groups). Through this research, students receive training across the boundaries of the traditional disciplines of chemistry.
The cucurbituril hosts are very attractive because they form extremely stable complexes with suitable guests in aqueous media. This research explores the following avenues: (1) Use of cucurbiturils as modular components of complex supramolecular systems, including at least two types of hosts. (2) Synthesis of functionalized cucurbiturils as active components for the preparation of well-defined supramolecular oligomers, as well as modification of the surface of metal and metal oxide nanoparticles, endowing them with high-affinity binding properties. (3) Electrochemical and EPR investigation of the polarity of the aqueous microenvironments adjacent to the cucurbituril cavity entrances. (4) Kinetics of cucurbituril exchange reactions between two different guests, with particular emphasis on the detection of ternary intermediates.
