Figure 2.

Magnetic alignment and flipping of macro–nanodiscs. ³¹P NMR spectra of unpurified DMPC:SMA-QA nanodiscs recorded as a function of time at 308 K and at various concentrations of YbCl₃. ³¹P peaks appearing at ~−15, −1, and 25 ppm indicate a perpendicular orientation, isotropic phase, and a parallel orientation, respectively. Here, the perpendicular and parallel orientations mean the orientation of the lipid bilayer normal relative to the direction of an external magnetic field. All of these NMR spectra were acquired using an Agilent 700 MHz NMR spectrometer.