Artigo Acesso aberto Produção Nacional Revisado por pares

Binding thermodynamics of synthetic dye Allura Red with bovine serum albumin

2016; Elsevier BV; Volume: 217; Linguagem: Inglês

10.1016/j.foodchem.2016.08.080

ISSN

1873-7072

Autores

Carini Aparecida Lelis, Eliara Acipreste Hudson, Guilherme Max Dias Ferreira, Gabriel Max Dias Ferreira, Luís Henrique Mendes da Silva, Maria do Carmo Hespanhol da Silva, Maximiliano Soares Pinto, Ana Clarissa dos Santos Pires,

Tópico(s)

Analytical Chemistry and Chromatography

Resumo

The interaction between Allura Red and bovine serum albumin (BSA) was studied in vitro at pH 7.4. The fluorescence quenching was classified as static quenching due to the formation of AR–BSA complex, with binding constant (K) ranging from 3.26 ± 0.09 to 8.08 ± 0.06 104 L.mol−1, at the warfarin binding site of BSA. This complex formation was driven by increasing entropy. Isothermal titration calorimetric measurements also showed an enthalpic contribution. The Allura Red diffusion coefficient determined by the Taylor-Aris technique corroborated these results because it reduced with increasing BSA concentration. Interfacial tension measurements showed that the AR–BSA complex presented surface activity, since interfacial tension of the water-air interface decreased as the colorant concentration increased. This technique also provided a complexation stoichiometry similar to those obtained by fluorimetric experiments. This work contributes to the knowledge of interactions between BSA and azo colorants under physiological conditions.

Referência(s)