Lipids mediating the interaction of metronidazole with cell membrane models at the air-water interface

In this paper, metronidazole, a known compound with microbicide effect, was incorporated in Langmuir monolayers of selected phospholipids in order to investigate the interactions of this compound with cell membrane models by using tensiometric, spectroscopic and morphological techniques. Surface pressure-area isotherms showed that selected amounts of metronidazole condense DPPC monolayers, but expand DPPE monolayers. Vibrational spectroscopy pointed that metronidazole adsorbs on the polar heads of the phospholipids, affecting the gauche conformations of the aliphatic chains, and different patterns were observed for DPPC and DPPE monolayers containing metronidazole in terms of Brewster angle microscopy images. As a result, distinctive interactions with DPPC and DPPE could be pointed regarding the incorporation of metronidazole with each lipid, leading to particular molecular arrangements at the air-water interface.