Synthesis and binding properties of carboxylphenyl-modified calix[4]arenes and cytochrome c.

Citation data:

Talanta, ISSN: 1873-3573, Vol: 79, Issue: 1, Page: 54-61

Publication Year:
Usage 137
Abstract Views 137
Captures 16
Readers 14
Exports-Saves 2
Citations 12
Citation Indexes 12
Repository URL:
An, Wen Ting; Jiao, Yong; Sun, Xiao Hua; Zhang, Xiao Ling; Dong, Chuan; Shuang, Shao Min; Xia, Ping Fang; Wong, Man Shing
Elsevier BV; Elsevier
Chemistry; Calix[4]arene carboxylphenyl derivatives; Cytochrome c; Fluorescence spectroscopy; Protein binding; Synthesis
article description
Two novel carboxylphenyl-modified calix[4]arenes, tetrakis-carboxylphenylcalix[4]arene (TCPC) and 1,3-bis-carboxylphenylcalix[4]arene (BCPC), as well as a corresponding analogue for comparison, tetrakis-phenylcalix[4]arene (TPC), have been synthesized by palladium-catalyzed Suzuki cross-coupling of arylboronic acid and tetrabromocalix[4]arene as a key step. The binding properties of these calix[4]arene 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 x 10(6) and 5.85 x 10(5)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.