Anomalous temperature dependence of peptide films at air–water interface

The tetrapeptide derivative Tyr-Gly-Phe-Ala-OBz (1) forms monolayers as confirmed by compressibility studies carried out at various temperatures. Peptide 1 monolayer exhibits an anomalous structural transition at 40 °C as evidenced by π–A isotherms recorded at different temperatures. The structural transition is also observed in aqueous solution of trifluoroacetate of peptide 1 as evidenced by fluorescence and Raman scattering intensity measurements.