Supramolecular structures from lysine peptides and carbon dioxide

摘要

The design, synthesis, and characterization of novel linear and cross-linked supramolecular polymers that are easily available from biologically friendly lysine peptides and carbon dioxide (CO2) are reported here. Polymeric structures 5, 6, and 19 readily form from peptides 2, 3, and 15, respectively, at ambient temperatures by simply bubbling CO2 through their solutions in apolar organic solvents (CHCl3, benzene) and even in the presence of 10% MeOH. The resulting gels can be easily isolated from solution, dried, and stored refrigerated for several months. At the same time, they may thermally release CO2 and convert back to the corresponding monomers. As a consequence, their structures and physical properties are switchable. They may also trap, store, and release foreign molecules. The typical entrapment procedure was demonstrated for tripeptide 3, CO2, and the commercially available dye coumarin 2.