Fig. 4. TEM images of amphiphile-like collagen mimic peptides (GPO)₅DD (a and b) and (GPO)₉DD (c and d). Peptide solutions with a concentration of 0.5 mg ml⁻¹ were prepared in 100 mM HEPES buffer, pH 7.0. Peptide (GPO)₅DD was incubated at 4 °C for 60 h. Peptide (GPO)₉DD was heated at 47 °C for 30 min and incubated at 4 °C for 60 h.