Cucurbiturils: molecular nanocapsules for time-resolved fluorescence-based assays.
A new fluorescent host-guest system based on the inclusion of the fluorophore 2,3-diazabicyclo[2.2.2]oct-2-ene (DBO) into the cavity of the molecular container compound cucurbit[7]uril (CB7) has been designed which possesses an exceedingly long-lived emission (690 ns in aerated water). The large binding constant of (4 +/- 1) x 10(5) M(-1) along with the resistance of the CB7.DBO complex toward external fluorescence quenchers allow the use of CB7 as an enhancer in time-resolved fluorescence-based assays, e.g., to screen enzyme activity or inhibition by using DBO-labeled peptides as substrates. The response of CB7.DBO to different environmental conditions and possible quenchers are described.
Marquez
Cesar
C
School of Engineering and Science, International University Bremen, Bremen D-28759, Germany. c.marquez@iu-bremen.de
Huang
Fang
F
Nau
Werner M
WM
D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry*; D001952:Bridged-Ring Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D002214:Capsules; D005456:Fluorescent Dyes / Q000737:chemistry*; D007093:Imidazoles / Q000138:chemical synthesis / Q000737:chemistry*; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils
D019086:Bridged Bicyclo Compounds, Heterocyclic; D001952:Bridged-Ring Compounds; D002214:Capsules; D005456:Fluorescent Dyes; D007093:Imidazoles; C484077:2,3-diazabicyclo(2.2.2)oct-2-ene; C454805:cucurbit(6)uril; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils