Fig. 8.

PEG-induced isotherm variations under hypothermia depend on lipid saturation. DPPC (a), SOPC (b), and SDPS (c) were applied on Milli-Q water subphase and monolayer compression was performed at 4°C or 37°C without (zero reference) or with 1 g/L of PEG 20,000 Da or PEG 35,000 Da. Surface pressure/mean molecular area isotherms were obtained as described in the “Materials and methods” section. Relative modification from pure Milli-Q water subphase was expressed as the percentage of variation in surface pressure (Π) measured at the collapse-point. Results are means ± SD of two independent experiments. **p < 0.001, 4°C versus 37°C