Morphology characterization of films from albumin and erythrosine dye: Effect of experimental procedures

Abstract

In this study, we prepared layer-by-layer (LbL) films from erythrosine (ERY) dye alternated with bovine serum albumin (BSA). BSA was chosen because is a model protein, and due to ability to bind with organic and inorganic molecules and transport various substances in the blood. ERY is typically used in foodstuffs, cosmetics, textiles, and medicine. It has been associated with health problems such as hyperactivity, asthma, and thyroid cancer. Dyes and other bioactive molecules bind to albumin; consequently, they contribute significantly to dye–protein interactions. The adsorption of erythrosine was monitored by UV–Vis spectrophotometry. Adsorption kinetics was fitted with the Johnson–Mehl–Avrami equation and the surface morphology of the films was investigated by atomic force microscopy. The concentration, pH, and temperature of solutions, analyzed using scaling laws, are key factors affecting the morphology of the films. The morphology of the films depends on the preparation procedures, which changes the wettability of the films. The successful preparation of LbL films from BSA and ERY demonstrates the suitability of this technique for building films of biomolecules and dyes and its strong dependence on experimental factors.