Voltammetric study and surface pressure isotherms describing Flunitrazepam incorporation into a distearoylphosphatidic acid film adsorbed at air/water and water/1,2-dichloroethane interfaces

The effect of Flunitrazepam (FNTZ) on molecular packing of distearoylphosphatidic acid (DSPA) adsorbed at the air/water and the water/1, 2–dichloroethane interface was investigated using cyclic voltammetry (CV) and surface pressure–molecular area isotherm. FNTZ incorporation into the DSPA monolayer changes the state of the film. The results indicate that a structuring effect dependent on the pH and the cation present in the base aqueous electrolyte takes place, which leads to a decrease in the permeability of the film.

► We studied the incorporation of FNTZ into DSPA films by cyclic voltammetry and π-area isotherms.
► Langmuir monolayers and lipids layer at liquid/liquid interfaces are employed.
► FNTZ produces a structuring effect changing the state and permeability of the film.
► This effect depends on the composition of aqueous phase.
► This paper contributes to the knowledge of non-specific interaction between drugs and bio membranes.