Photo-oxidation of Langmuir films as mimetic systems of human lung membranes mediated by aluminum-chlorine phthalocyanine

Abstract

In this scientific initiation project, the interaction at the molecular level between the drug aluminum-chlorine phthalocyanine, a second-generation photosensitizer (PS), and simplified model systems of human lung surfactant cell membrane will be evaluated. The phospholipid membranes will be spread in an aqueous interface, together with different molar ratios of the phthalocyanine derivative, for the controlled formation of monomolecular films via the Langmuir technique. The films will have saturated (DPPC) and unsaturated (POPG) phospholipids in their composition. The characterization of the phospholipid monolayers will be performed through the surface pressure values by the occupied molecular area. In a later step, the photoactivation of phthalocyanine will be induced for the oxidation of phospholipids and the PS and membrane binding mechanisms will be investigated by infrared absorption spectroscopy (FTIR) of Langmuir-Schaefer (LS) films. The objective will be to observe the effects resulting from the association of phospholipids with phthalocyanine, in addition to determining the changes in the membrane after oxidative reactions, subsequent to the photoactivation of PS. (AU)