Applications of Fluorescent Displacement-Based ... - Jacobs University

CHAPTER 1
Introduction
to form discrete entities. Host-guest complexes are representations of prototypal
supramolecular architectures, which after Pederson’s metal ions encapsulation by
crown ethers, [1] opened vast territories. Inclusion of smaller molecules into
container compounds does not only afford fundamental insight into the
intermolecular forces governing complexation, but also opens new horizons to a
myriad of practical applications ranging from analyte sensing to drug delivery,
and to the design of synthetic enzymes.
Figure 1.1.1 Cover picture in Angewandte Chemie International Edition with the
occasion of the special topical issue on Supramolecular Chemistry. The image
illustrates an example of molecular self-organization based on the work of J.-M.
Lehn, which is similar to the DNA helix formation. Double-helical complexes
called helicates, form spontaneously from penta(bipyridine) ligands and Cu + ions
in solution.
One specific area where principles of supramolecular chemistry have
become popular is that of analyte sensing. Particularly, host-guest complexes
involving chromogenic or fluorogenic guests incorporated into supramolecular
structures, sensitive to external stimuli such as pH, metal ions, and particularly
organic or biomolecular analytes, are of immediate relevance towards practical
applications. [6-8] Traditionally, a functional chemosensor needs to contain a
binding site for the analyte, which in biochemical applications is very often an
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