FIGURE 9.

The C=O stretching and amide I bands of the FTIR spectra exhibited by L₂₄-containing PE bilayers. The absorbance spectra shown were acquired with mixtures containing 3.3 mol % L₂₄ under conditions where the lipid bilayer hosts are in the L_β-phase and L_α-phase states. The dashed lines mark the absorption maxima (1656 cm⁻¹) of the amide I absorption bands arising from fully proteated α-helical peptide domains. The small absorption bands centered near 1670 cm⁻¹ arise from small amounts of trifluoroacetate counterions that were not completely removed during sample preparation.