Study of the Mode of Inclusion for 7-Hydroxyflavone in beta-Cyclodextrin Complexes

Autor(es)

Fumes, Bruno H. ^[1] ; Guzzo, Mariana R. ^[1] ; Machado, Antonio E. H. ^[2] ; Okano, Laura T. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, BR-14040901 Ribeirao Preto - Brazil

^[2] Univ Fed Uberlandia, Inst Quim, Lab Fotoquim & Ciencia Mat, BR-38400902 Uberlandia, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Brazilian Chemical Society; v. 27, n. 2, p. 382+, FEB 2016.
• Citações Web of Science: 3

Resumo

This paper aimed to study the mode of inclusion for 7-hydroxyflavone (7HF) in beta-cyclodextrin (beta-CD) complex in basic (pH 12) and acid (pH 4.5) media. The thermodynamic parameters of the complexation of 7HF with beta-CD were evaluated by means of steady-state fluorescence and solubility measurements at several temperatures. The 7HF-beta-CD inclusion complex was spontaneously formed at 1:1 stoichiometry in both basic and acid media. The high number of hydrogen bonds formed between the host and the guest molecules favored complexation in the basic medium, with a ground-state equilibrium constant (K) of 990 +/- 130 mol(-1) L, at 25 degrees C. The quantum-mechanics calculations showed that complexation of 7HF (neutral or anionic form) with beta-CD occurred mainly via the phenyl group of the flavonoid. This result agreed with the induced circular dichroism signal of 7HF complexed with beta-CD. (AU)

• Processo FAPESP: 09/17229-5 - Estudo sobre a Complexação de Flavonóides com Ciclodextrinas
• Beneficiário: Bruno Henrique Fumes
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica