title: Time-resolved fluorescence anisotropy as a tool to study guest-cucurbit[n]uril-protein ternary supramolecular interactions.
abstract: Ternary supramolecular complexes involving cucurbit[n]urils and proteins are of potential interest for improving drug transport and delivery. We report here time-resolved fluorescence studies for acridine orange complexes with cucurbit[7]uril and cucurbit[8]uril in the presence of human serum albumin as a model system. A detailed characterization of the fluorescence lifetime and anisotropy properties of the different acridine orange complexes with cucurbit[n]urils and human serum albumin was performed. Of particular importance is the analysis of the stepwise binding for acridine orange-cucurbit[8]uril complexes and the assignment of the fluorescence and anisotropy properties to the 2 : 1 complex. Anisotropy decay measurements were essential to detect protein-bound species and to discriminate between different complexes. Based on the fluorescence evidence, ternary interactions with the protein are suggested for the acridine orange-cucurbit[7]uril complex but not for the cucurbit[8]uril complex. We highlight here the usability and sensitivity of the combined fluorescence analysis.
authors: Laboratorio de Química Biológica, Departamento de Química Física, Facultad de Química, Pontificia Universidad Católica de Chile, Santiago, Chile. dlfuente@uc.cl.
authors: Karina
authors: K
authors: Scholtbach
authors: Ítalo
authors: Í
authors: Venegas
authors: Cornelia
authors: C
authors: Bohne
authors: Denis
authors: D
authors: Fuentealba
mesh_terms: D000165:Acridine Orange / Q000737:chemistry; D001952:Bridged-Ring Compounds / Q000737:chemistry*; D005454:Fluorescence Polarization / Q000379:methods*; D006801:Humans; D007093:Imidazoles / Q000737:chemistry*; D012709:Serum Albumin / Q000737:chemistry*; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils
chemical_list: D000165:Acridine Orange; D001952:Bridged-Ring Compounds; D007093:Imidazoles; D012709:Serum Albumin; C456276:cucurbit(7)uril; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils; C507198:cucurbit(8)uril