Department of Chemistry
Synthesis and binding properties of carboxylphenyl-modified calixarenes and cytochrome c
Two novel carboxylphenyl-modified calixarenes, tetrakis-carboxylphenylcalixarene (TCPC) and 1,3-bis-carboxylphenylcalixarene (BCPC), as well as a corresponding analogue for comparison, tetrakis-phenylcalixarene (TPC), have been synthesized by palladium-catalyzed Suzuki cross-coupling of arylboronic acid and tetrabromocalixarene as a key step. The binding properties of these calixarene derivatives with bovine heart cytochrome c (cyt c) in dimethylformamide (DMF) was investigated by fluorescence spectroscopy. The binding affinity in the order of TCPC > BCPC ≫ TPC reflects a clear dependence on the number of carboxyl ligating groups attached onto a receptor and suggests the electrostatic force may be the predominant factor driving the complexing process. The stable 1:1 complexes of TCPC and BCPC with cyt c were evidenced with the binding constants of 3.15 × 106 and 5.85 × 105 L mol-1, respectively. Due to a large overlap between the emission spectrum of TCPC and the absorption spectrum of cyt c, and a short interaction distance (estimated to be 5.6 nm) between them, the fluorescence quenching of TCPC upon complexation with cyt c is attributed to an efficient energy transfer. © 2009 Elsevier B.V. All rights reserved.
Calixarene carboxylphenyl derivatives, Cytochrome c, Fluorescence spectroscopy, Protein binding, Synthesis
Source Publication Title
An, Wen Ting, Yong Jiao, Xiao Hua Sun, Xiao Ling Zhang, Chuan Dong, Shao Min Shuang, Ping Fang Xia, and Man Shing Wong. "Synthesis and binding properties of carboxylphenyl-modified calixarenes and cytochrome c." Talanta 79.1 (2009): 54-61.