Fig. 2. (a) Absorbance and emission spectra of Trp(redBODIPY)-labelled peptide 8 (10 μM) in EtOH. Normalised absorbance (solid line) and fluorescence emission (dashed line, λexc.: 520 nm). (b) Fluorogenic behaviour of cyclopeptide 8 (40 μM) in hydrophilic and hydrophobic media (70-fold). Peptide 8 was incubated in PBS (black) or in phosphatidylcholine liposome suspensions (red, λexc.: 520 nm). (Inset) Naked eye pictograms of both solutions under a hand-held UV lamp using 365 nm excitation. (c) Stability of peptides in a protease cocktail by HPLC monitoring. (d) Viability of HeLa cells after incubation with different concentrations of peptide 8. Values are presented as means ± s.d. (n = 4). Non-significant differences (p > 0.05) were observed between the untreated control and any of the treatments.
