Detection and Mechanistic Studies of Multicomponent Assembly by
Fluorescence Resonance Energy Transfer
Ronald K. Castellano
Stephen L. Craig
Colin Nuckolls
Julius Rebek
10.1021/ja994397m.s001
https://acs.figshare.com/articles/journal_contribution/Detection_and_Mechanistic_Studies_of_Multicomponent_Assembly_by_Fluorescence_Resonance_Energy_Transfer/3678750
The kinetics and thermodynamics of multicomponent assembly in organic solution are investigated
using fluorescence resonance energy transfer (FRET). Calix[4]arenes functionalized with ureas on their wider
rims dimerize in organic solution, via intermolecular hydrogen bonding, to form encapsulation complexes.
When one calixarene component is outfitted with a donor fluorophore and the other with an acceptor,
dimerization brings the chromophores within 20 Å, a distance suitable for efficient energy transfer to occur
between them. Excitation of the donor results in two colors of emitted light: one fluorescence band at the
donor emission wavelength, and a second at the acceptor emission wavelength signaling the noncovalent union
of three speciesdonor, acceptor, and small-molecule guest. By monitoring these wavelengths, assembly and
dissociation processes are observed in real time at nanomolar concentrations. Rate and association constants
for assembly processes are determined for the first time, and they reveal unexpected contributions from the
structure and concentration of the monomer. Finally, the combination of FRET and the molecular recognition
capabilities of the encapsulation complexes provides a sensitive and specific method for small-molecule sensing.
2000-08-08 00:00:00
encapsulation complexes
rims dimerize
solution
multicomponent assembly
assembly processes
dissociation processes
Multicomponent Assembly
Fluorescence Resonance Energy Transfer
Mechanistic Studies
association constants
fluorescence band
form encapsulation complexes
recognition capabilities
noncovalent union
donor fluorophore
fluorescence resonance energy transfer
donor results
acceptor emission wavelength
FRET
energy transfer
nanomolar concentrations
donor emission wavelength
calixarene component