Molecular spectroscopic on interaction between Methyl hesperidin and Buman serum albumin

The interaction of Methyl hesperidin (MH) with Buman serum albumin was studied by spectroscopic methods including Fluorescence quenching technology, UV absorbance spectra and Fourier transform infrared (FT-IR) spectroscopy under simulative physiological conditions. The result of fluorescence titration revealed that Methyl hesperidin could quench the intrinsic fluorescence of BSA and the quenching mechanism should be a combined quenching process. The binding constants at three temperatures (296, 303, and 310 K) were 1.82, 2.69, and 3.4 × 104 L mol−1, respectively. The distance between donor (BSA) and acceptor (MH) was 5.54 nm according to the Förster theory of non-radiation energy transfer. In addition, FT-IR spectroscopy showed that the binding of MH to BSA changed the secondary structure of protein.

The fluorescence emission spectra of MH-BSA system at excited 280 nmFigure optionsDownload as PowerPoint slideHighlights
► Multi-spectroscopy techniques were associated to study the interactions between MH and BSA.
► The quenching mechanism of fluorescence was a combined quenching process.
► The binding constants were calculated.
► The change of the BSA secondary structure induced by MH binding was measured by FT-IR spectroscopic methods.
► These results are important for clinical pharmacology.