FIGURE 2.

50.3-MHz ¹³C{¹⁹F} REDOR spectra of a 50-50 mixture of [1-¹³C]Ala₁₀-[¹⁵N]Gly₁₁-(KIAGKIA)₃-NH₂ and [2-²H, 3-¹⁹F]Ala₁₀-(KIAGKIA)₃-NH₂ incorporated into synthetic MLVs of DPPG/DPPC (1:1) at a lipid/peptide molar ratio of 20 after 48 rotor cycles of dipolar evolution with magic-angle spinning at 5000 Hz. (Top) Frozen, fully hydrated sample. (Bottom) Lyophilized sample (in a protecting trehalose matrix). The full-echo spectra are normalized with respect to the carbonyl peak at 177.2 ppm. The experimental temperature was ∼−10°C for the lyophilized sample and −25°C for the hydrated sample. Both samples weighed ∼300 mg. The spectrum of the hydrated sample involved the accumulation of 64K scans in 3 days, and the spectrum of the lyophilized sample, 32K scans, in 1.5 days.