Synthesis and physicochemical evaluation of fluorinated lipopeptide precursors of ligands for microbubble targeting

Ligand-targeted microbubbles are focusing interest for molecular imaging and delivery of chemotherapeutics. Lipid–peptide conjugates (lipopeptides) that feature alternating serine–glycine (SG) n segments rather than classical poly(oxyethylene) linkers between the lipid polar head a targeting ligand were proposed liposome-mediated, selective anticancer drugs. Here, we report synthesis perfluoroalkylated lipopeptides ( F -lipopeptides) bearing two hydrophobic chains (C 2 +1 , = 6, 7, 8, 1 – 3 ) grafted through lysine moiety on hydrophilic chain composed lysine–serine–serine (KSS) sequence followed by 5 SG sequences. These -lipopeptides precursors lipopeptide conjugates. A hydrocarbon counterpart with C 10 H 21 4 was synthesized comparison. The capacity to spontaneously adsorb at air/water interface form monolayers when combined dipalmitoylphosphatidylcholine (DPPC) investigated. demonstrated markedly enhanced tendency interface, equilibrium surface pressures reaching ?7–10 mN m ?1 versus less only their analog . penetrate in DPPC both liquid expanded (LE) condensed (LC) phases without interfacial film destabilization. By contrast, provokes delipidation film. incorporation shell dipalmitoylphosphatidylethanolamine-PEG2000 decreased mean diameter increased stability, best results being obtained 8 17 -bearing led larger significantly lower stability.