Crucially, this analysis is done in a specific order. First, the vesicle references without peptide in salt-free buffer (bottom curves in 2A and 2D) are analyzed using the model described above. These serve as a reference for fitting the curves of vesicles with peptide, but still in salt-free buffer, shown by the bottom curve in figures 2B, 2C, 2E and 2F. Importantly, the change in the SLDs of the shells due to the peptide insertion are explicitly calculated, and can, with the references, be separated from potential structural changes in the bilayer. These fits in turn serves as reference for the vesicles subjected to osmotic shock, and allow changes in the buffer SLD due to salt influx to be considered explicitly, and separately from potential structural changes.