Preparation and characterization of adamantyl derivatives of feroccene peptides and study of their interaction with liposomes as model membranes

A series of homo- and heteroannularly substituted adamantyl derivatives of ferrocene peptides type I R-Fn-NHCO-CH2-Ad and II R-Fn-NH-L-Ala-CH2-Ad (R=H, MeOOC and HOOC) has been synthesized and incorporated into liposomes. They combine two biomedically significant and structurally interesting molecules, the adamantane moiety and the ferrocene molecule. The adamantane moiety possesses membrane compatible features while the ferrocene containing compounds have received much attention in recent years due to the possibility of building redox-switching or -sensing systems of a molecular or supramolecular nature. The liposome formulations of adamantyl derivatives of ferrocene peptides were characterized by Dynamic Light Scattering and Differential Scanning Calorimetry. It was demonstrated that adamantyl derivatives of ferrocene peptides incorporated into the liposome significantly affect the structure of the lipid bilayer. These results indicate that newly synthesized adamantyl derivatives of ferrocene peptides might be useful for different biomedical application, from studies of molecular recognition processes on cell membrane to usage in electrochemical sensing and design of redox-sensitive liposome delivery systems