Comparative studies of the interaction between ferulic acid and bovine serum albumin by ACE and surface plasmon resonance

Abstract

Affinity capillary electrophoresis (ACE) was used to study the interaction between ferulic acid (FA) and BSA. The interaction between FA and BSA was facilitated by injecting FA into a BSA-containing running buffer. Both mobility ratio and mobility shift assays were performed to deduce the binding constant (K(b)). However, the K(b )value obtained with the mobility ratio assay was only approximately 20% of that extracted from the mobility shift assay. The former assay yielded a K(b) value (5.6 +/- 0.4 x 10(4) M(-1)), which compares well with the result obtained with surface plasmon resonance (SPR) (5.1 +/- 0.6 x 10(4) M(-1)). The discrepancy between the mobility ratio and mobility shift assays suggests that the data extrapolation from the mobility ratio should be more reliable for cases when both changes in the EOF and viscosity of the running buffer are important. The work demonstrates that ACE, a solution-based technique, and SPR, a technique addressing interfacial processes, are highly complementary to each other and the comparative studies are confirmatory and allow binding constants to be accurately determined.

Binding of naturally occurring hydroxycinnamic acids to bovine serum albumin

“…Non-covalent interactions of chlorogenic acid with BSA have been studied by Prigent et al [33], who reported that these interactions decrease with the increasing temperature while pH and ionic strength had no pronounced effect. Zhang et al [34] reported the K b for ferulic acid-BSA system determined by affinity capillary electrophoresis which is in good agreement with our result. By contrast, Rawel et al [20] determined binding constant of ferulic acid-BSA system by fluorescence quenching method and Hummel-Dreyer/size exclusion chromatography, where first method gave similar results to our data and K b obtained by second method was significantly lower.…”

Nature of hydroxycinnamate-protein interactions

“…chlorogenic and ferulic acid) in turn promoted binding studies involving plasma proteins (e.g. with serum albumin) underlining their role for the transport of these compounds (Kang et al 2004;Zhang et al 2007). The nature of binding seems to be a noncovalent type, where the hydrophobic pockets in the protein and hydrogen bonds seem to be the determining factors.…”

Interaction of glycyrrhetinic acid, furosemide and hydrochlorothiazide with bovine serum albumin and their displacement interactions: capillary electrophoresis and fluorescence quenching study

“…Different methodologies have been developed to evaluate drug-protein interactions, such as the traditional equilibrium dialysis (Kwong, 1985), ultracentrifugation (Kwong, 1985), ultrafiltration (Kurz, 1986), gel filtration (Ascoli et al, 1995), crystallographic studies of HSA-solute complexes (Carter et al, 1989) and spectroscopic measurements such as fluorescence quenching (Parikh et al, 2000;Zhou et al, 2007). In recent years, the use of capillary electrophoresis (CE) to study biological interactions has become increasingly popular (Martínez-Gómez et al, 2006;Zhang et al, 2007;Øtergaard and Heegaard, 2003). However, binding parameters such as binding constants obtained by different methods are sometimes quite distinct .…”

“…Busch et al (1997) compared five CE methods and they concluded that these methods were complementary rather than competitive. Zhang et al (2007) made comparative studies of the interaction between ferulic acid and bovine serum albumin by affinity capillary electrophoresis (ACE) and surface plasmon resonance (SPR). They found that the binding constant obtained with the mobility ratio assay was only 20% of that extracted from the mobility shift assay but was in excellent agreement with that by SPR.…”