MONOLAYER FILMS OF SURFACTANT DERIVATIVES OF METHYLENE-BLUE

Surfactant derivatives of methylene blue have been synthesized and shown to form stable monolayer films at the air-water interface. From a comparison of experimental II-A curves and dimensions derived from molecular models, probable orientations of the methylene blue chromophore in these films are discussed. The absorption spectra of glass-supported monolayer arrays of surfactant methylene blue derivatives are reported and show differences based on the number of hydrocarbon chains attached to the chromophore, the glass pretreatment, subphase counterion, and surface pressure at which the film was transferred onto the glass surface. The absorption spectra of methylene blue adsorbed on to glass surfaces from aqueous solution are described and shown to depend on glass pretreatment. © 1979.