FIGURE 2.

The phase separation of LPS R45 solid supported Langmuir-Blodgett monolayers is not maintained in asymmetric bilayers. Solid supported Langmuir-Blodgett monolayers (A,B) were imaged by AFM in air while imaging of Langmuir-Blodgett bilayers (C,D) was conducted in buffer. (A,a) LPS R45 monolayer; liquid expanded (LE) domains appear higher compared to the liquid condensed (LC) domains in the attractive regime of the AFM AC-mode; (B,b) PL (PE:PG:CL; 81:17:2; w/w/w) monolayer; (C,c) LPS R45/PL bilayer with the PL adsorbed on the solid support and the LPS R45 oriented to the buffer; and (D,d) PL/LPS R45 bilayer with the LPS adsorbed on the solid support and the PL oriented to the buffer. Only the LPS R45 monolayer showed a phase separation. Monolayer formation, Langmuir-Blodgett transfer and AFM imaging were performed in 100 mM KCl, 5 mM MgCl₂, 5 mM HEPES buffer at pH 7.0 and T = 21°C. Lateral pressure of the monolayer during transfer to the mica was p = 20 mN/m. AFM height images are shown with a gray scale range of 5 nm.