ja994397m_si_001.pdf (473.48 kB)
Detection and Mechanistic Studies of Multicomponent Assembly by Fluorescence Resonance Energy Transfer
journal contribution
posted on 2000-08-08, 00:00 authored by Ronald K. Castellano, Stephen L. Craig, Colin Nuckolls, Julius RebekThe 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.
History
Usage metrics
Categories
Keywords
encapsulation complexesrims dimerizesolutionmulticomponent assemblyassembly processesdissociation processesMulticomponent AssemblyFluorescence Resonance Energy TransferMechanistic Studiesassociation constantsfluorescence bandform encapsulation complexesrecognition capabilitiesnoncovalent uniondonor fluorophorefluorescence resonance energy transferdonor resultsacceptor emission wavelengthFRETenergy transfernanomolar concentrationsdonor emission wavelengthcalixarene component
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC