Superimposed 1H-15N HSQC spectra of the HAfp23 peptide in isotropic bicelles (biPC) of different size and charge at pH 7. Shown are spectra for small bicelles (biPC, q=0.33 ± 0.06) without net charge (black), bicelles with DMPS (blue), DMPS/DHPS (green), Et-DMPC (red), and medium-sized neutral bicelles (med biPC, q=0.51, orange). Unlabeled cross peaks correspond to the SGKKKKD polyionic "host" tail (Han and Tamm 2000), used to aid in the sample preparation (Lorieau et al. 2010). Spectra were collected in the absence of alignment media.